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  • Polymer and Materials Science  (3,277)
  • General Chemistry  (2,015)
  • Cell & Developmental Biology  (441)
  • 1995-1999  (5,733)
  • 1945-1949
  • 1997  (5,733)
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  • 1995-1999  (5,733)
  • 1945-1949
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  • 1
    Electronic Resource
    Electronic Resource
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 35 (1997), S. 183-192 
    ISSN: 0887-624X
    Keywords: polyanhydride ; adipic anhydride ; ring-opening polymerization ; block copolymers ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Homopolymers of adipic anhydride (AA) and block copolymers of ∊-caprolactone (∊-CL) and AA have been synthesized with aluminum triisopropoxide as an initiator. Homopolymerization was studied at 20°C in toluene and methylene chloride (CH2Cl2). The end-group analysis agrees with a coordination insertion mechanism based on the acyl-oxygen cleavage of the AA ring. Living poly(∊-caprolactone) (PCL) chains are very efficient macro-initiators for the polymerization of AA, with formation of diblock copolymers of a narrow molecular weight distribution. At our best knowledge, low molecular weight ω-aluminum alkoxide PCL macroinitiators (Mn 〈 1000) allow the first valuable synthesis of PAA with a molecular weight as high as 58,000 and a quite narrow polydispersity (Mw/Mn = 1.2). Size-exclusion chromatography (SEC) and 13C NMR confirm the blocky structure of the copolymers, in agreement with DSC that shows two melting endotherms and two glass transitions characteristic of the crystalline and amorphous phases of PCL and PAA, respectively. Block copolymers of ∊-CL and AA are also sensitive to hydrolysis, which makes them possible candidates for biomedical applications. Initiation of the AA polymerization in bulk with aluminum triisopropoxide in the presence of various ligands is also discussed. © 1997 John Wiley & Sons, Inc.
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  • 2
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    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 35 (1997), S. 227-230 
    ISSN: 0887-624X
    Keywords: IPN ; frontal polymerization ; propagating front ; SIN ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: We report a new method for the preparation of a simultaneous interpenetrating polymer network (SIN) using a thermal propagating front of two independent and noninterfering polymerization mechanisms. The system consists of the free radical crosslinking of triethylene glycol dimethacrylate (TGDMA) and the amine/BCl3 · amine curing of diglycidyl ether of bisphenol A (DGEBA). The front velocity dependence on the percentage of each monomer shows a minimum at 45% TGDMA. Temperature profile measurements indicate that a single reaction front propagates. A colored opaque material is produced, but SEM and TEM analysis were inconclusive whether phase separation occurred. Samples as large as 5 cm in diameter were prepared with this method. We conclude that this method should be especially suited for preparing large samples of IPNs in which significant phase separation occurs. © 1997 John Wiley & Sons, Inc.
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  • 3
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    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 35 (1997), S. 255-261 
    ISSN: 0887-624X
    Keywords: controlled synthesis ; amphiphilic block copolymer ; pendant glucose residues ; vinyl ether ; living cationic polymerization ; microphase-separated structure ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Amphiphilic block copolymers of vinyl ethers (VEs) of the type  - [CH2CH(OCH2CH2OR)]m - [CH2CH(OiBu)]n - were synthesized by living cationic polymerization, where R is a D-glucose residue, and m and n are the degrees of polymerization (m = 20-50; n = 11-89). To obtain them, sequential living block copolymerization of isobutyl vinyl ether (IBVE) and the vinyl ether carrying 1,2:5,6-diisopropylidene-D-glucose residue was conducted by using the HCl adduct of IBVE, CH3CH(OiBu)Cl, as initiator in conjunction with zinc iodide. These precursor block copolymers had a narrow molecular weight distribution (M̄w/M̄n ∼ 1.1) and a controlled composition. Treatment of them with a trifluoroacetic acid/water mixture led to the target amphiphiles. The solubility of the amphiphilic block copolymers in various solvents depended strongly on composition or the m/n ratio. Their solvent-cast thin films were observed, under a transmission electron microscope, to exhibit various microphase-separated surface morphologies such as spheres, cylinders, and lamellae, depending on composition. © 1997 John Wiley & Sons, Inc.
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  • 4
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    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 35 (1997), S. 299-305 
    ISSN: 0887-624X
    Keywords: poly(methylmethacrylate) ; pulse radiolysis ; charge scavenging ; doped polymers ; excited states ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The spectra of transients produced in pulse-irradiated pure poly(methyl methacrylate), PMMA, at room and ∼ 130 K temperatures were measured. The intermediates were identified as PMMA radicals and radical anions. In the pulse-irradiated PMMA-pyrene (Py) system the solute excited states and radical ions were produced. Scavenging of negative charges by Py was directly observed at 130 K in a µs time scale. Py fluorescence was found to be produced mainly as a result of Čerenkov photoexcitation. At room temperature, some contribution of ionic mechanism to Py fluorescence formation was found. © 1997 John Wiley & Sons, Inc.
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  • 5
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    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 35 (1997), S. 329-344 
    ISSN: 0887-624X
    Keywords: carbocationic polymerization ; isobutylene ; metallocenes ; noncoordinating anions ; styrenics ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The initiation and catalysis of isobutylene polymerization from several new metallocene and nonmetallocene initiator-catalysts that contain the noncoordinating anions (NCA), B(C6F5)4- and RB(C6F6)3-, is reported. Application of these initiator-catalysts is extended to styrenics and vinyl ethers. The NCA does not contribute to termination and can be used in low concentrations compared with conventional Lewis acids. These qualities provide for isobutylene polymerizations that yield low Mn oligomers or high Mn polymer, dependent upon the initiator and polymerization conditions. Mechanistic aspects of initiation, transfer and termination as well as the participation of adventitious water are considered for each class of initiator-catalyst. The influence of the NCA on the stereoregularity of cationic styrene polymerization is also considered. NCAs do not cause the stereospecific carbocationic polymerization of styrene. We suggest that under conditions not conducive to carbocationic polymerization, NCA/metallocenes mediate the coordination polymerization of styrene. © 1997 John Wiley & Sons, Inc.
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  • 6
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    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 35 (1997), S. 377-383 
    ISSN: 0887-624X
    Keywords: biodegradability ; poly(lactic acid) ; lactic acid-depsipeptide copolymer ; ring-opening copolymerization ; functionalized side-group ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Since poly(lactic acid) is the biodegradable polyester having low immunogenicity and good biocompatibility, it is utilized as a medical material. However, poly(lactic acid) is a water-insoluble crystalline polymer having no reactive side-chain group. Thus, the use of poly(lactic acid) is limited. To modify the properties of poly(lactic acid) and to introduce the functionalized pendant groups to poly(lactic acid), we synthesized two kinds of lactic acid-depsipeptide copolymers with reactive pendant groups, namely poly[LA-(Glc-Lys)] and poly[LA-(Glc-Asp)]. This was done through ring-opening copolymerizations of L-lactide with the corresponding protected cyclodepsipeptides, cyclo[Glc-Lys(Z)] and cyclo[Glc-Asp(OBzl)], and subsequent deprotection of benzyloxycarbonyl and benzyl groups, respectively. By changing the mole fraction of the corresponding depsipeptide units, the solubility, thermal transition and degradation behavior of the modified poly(lactic acid) could be varied. © 1997 John Wiley & Sons, Inc.
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  • 7
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    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 35 (1997), S. 393-398 
    ISSN: 0887-624X
    Keywords: terbium ; poly(methacrylic acid) ; tacticity ; fluorescence ; lifetime ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The binding properties of trivalent metal ions to polyelectrolytes were investigated through the use of terbium [Tb(III)] in fluorescence studies. The fluorescence intensity and lifetimes of the lanthanide ions are directly dependent upon the number of water molecules bound to their inner coordination sphere. The more efficiently a ligand coordinates to a lanthanide ion, the more water molecules are expelled and consequently, the greater the fluorescence intensity and lifetime. This effect was used to probe for differences in the complexation behavior of tactic polymers. Aqueous solutions of isotactic and syndiotactic poly(methacrylic acid) (PMA) were neutralized and complexed with Tb(III) ions. The fluorescence intensity of the 286 nm hypersensitive excitation band was monitored and the lifetimes were measured using several excitation wavelengths. It was found that the isotactic PMA/Tb(III) complex exhibited a six times greater fluorescence intensity than the syndiotactic PMA complex. Lifetime measurements gave the number of water molecules coordinated by Tb(III) in the isotactic complex to be 2.4 while 3.4 waters remained bound to the Tb(III) ion in the syndiotactic PMA complex. These results indicate that isotactic PMA has the greater binding affinity towards Tb(III) ions. © 1997 John Wiley & Sons, Inc.
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  • 8
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    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 35 (1997), S. 485-491 
    ISSN: 0887-624X
    Keywords: 2-methylene-1,3-dioxepane ; cyclic ketene acetal ; cationic polymerization ; activated carbon black ; 1,2-polymerization ; ring-opening polymerization ; ring-retained polymerization ; initiator ; catalyst ; heterogeneous catalysis ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: ---The stable cyclic ketene acetal, 2-methylene-1,3-dioxepane, 7, has been polymerized cationically in pentane, CH2Cl2 and THF at 25°C to form a polymer which is composed of both ring-opened (40-50%) and ring-retained (50-60%) structures. Initiation was catalyzed by using H2SO4-supported on activated carbon black. This unique outcome differs significantly from the cationic polymerization of several other five- and six-membered ring cyclic ketene acetals which gave 100% 1,2-vinylpolymerization under these conditions. As the polymerization temperature increased in cationic polymerization of 7 the ring-opened content increased and the molecular weight of the polymers decreased in such solvents as cyclohexane, 1,2-dichloroethane, dimethoxyethane, and bis-(2-methoxyethyl) ether. The mechanism of this polymerization is discussed. This research also illustrated the ability to initiate the cationic polymerization of cyclic ketene acetals by acidified carbon black while avoiding subsequent polymer decomposition. © 1997 John Wiley & Sons, Inc.
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  • 9
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    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 35 (1997), S. 447-453 
    ISSN: 0887-624X
    Keywords: polyether ; polyester ; aryl ether ; nucleophilic substitution ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Arene-iron chemistry was applied in the synthesis of a novel liquid crystalline polymer. The chemistry, which is based on iron cyclopentadienyl (FeCp) arene complexes, allows sequential nucleophilic substitution of the chlorides from 1,3-dichlorobenzene-FeCp complex and photolytic decomplexation of the products to afford asymmetrical aryl ethers. This methodology provides easy access to novel polyether-esters, and is potentially useful in the synthesis of various functional polyarylates. © 1997 John Wiley & Sons, Inc.
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  • 10
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    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 35 (1997), S. 439-446 
    ISSN: 0887-624X
    Keywords: poly(phenylisocyanide) ; NMR ; GPC ; light-scattering techniques ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The preparation of N-phenyl-substituted poly(isocyanide) (N-φ-PIM) utilizing a Ni(II) catalyst in methanol yields a brown material having a number average molecular weight of about 2000. Analysis of this “as prepared” polymer indicates that a rigid rod structure is present in the derived solid. Dissolution of this “as prepared” N-φ-PIM in halocarbon solvents or THF apparently leads to unraveling of the helical polymer with subsequent aggregation and precipitation of materials that have different properties from the original. These processes have been investigated by NMR, GPC, and light-scattering techniques in THF and other solvents. UV spectroscopy has been utilized to follow the kinetics of the aggregation process in solution. X-ray diffraction (XRD) measurements have been employed to investigate the changes attendant with precipitation. An explanation of these observations is offered that implicates the uncoiling of the rigid rod helix as the most important step in defining subsequent physical and chemical properties of the ultimate amorphous polymer. © 1997 John Wiley & Sons, Inc.
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  • 11
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    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 35 (1997), S. 463-474 
    ISSN: 0887-624X
    Keywords: π-conjugated polymer ; polythiophene ; phenolic substituent ; hindered phenolic substituent ; nickel-promoted ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Dehalogenation polycondensation of 3-(4-methoxyphenyl)-2,5-dibromothiophene with Mg and a zerovalent nickel complex as well as chemical oxidative polymerization of 3-(4-methoxyphenyl)thiophene with FeCl3 gives poly[3-(4-methoxyphenyl)thiophene-2,5-diyl] P3(4-MeOPh)Th. Treatment of soluble P3(4-MeOPh)Th with BBr3 converts the OCH3 group to an OH group and gives poly[3-(4-hydroxyphenyl)thiophene-2,5-diyl] P3(4-OHPh)Th. Oxidative polymerization of 3-[3,5-di-t-butyl-4-{(trimethylsilyl)oxy}phenyl]thiophene with FeCl3 in an aqueous medium directly affords another kind of polythiophene with a sterically hindered phenolic group, poly[3-(3,5-di-t-butyl-4-hydroxyphenyl)thiophene-2,5-diyl] P3(4-OH-3,5-tBu2Ph)Th. An organometallic dehalogenation polymerization using a nickel complex also affords P3(4-OH-3,5-tBu2Ph)Th. All the polymers described above show strong photoluminescence in a region of 500-600 nm. Oxidation of P3(4-OH-3,5-tBu2Ph)Th with PbO2 gives stable radical species as confirmed by IR and ESR spectroscopy. Electrochemical redox behavior of the polymers is compared with that of other polythiophenes. © 1997 John Wiley & Sons, Inc.
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  • 12
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    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 35 (1997), S. 499-507 
    ISSN: 0887-624X
    Keywords: amino acids ; leucine-tyrosine ; polyureas ; polyamides ; polyesteramide ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Monomers with leucine-tyrosine linkages were synthesized using diphenyl phosphoryl azide as a coupling reagent. Leucyltyrosylpoly(propylene glycol) bis(2-aminopropyl ether) tyrosylleucine (monomer 1) has a longer spacer: poly(propylene glycol) bis(2-aminopropyl ether) (Jeffamine® D-400), and leucyltyrosyliminohexamethyleneiminotyrosylleucine (monomer 2) has a shorter spacer: hexamethylenediamine. Polyureas from monomers 1 and 2 with hexamethylene diisocyanate and methylenedi-p-phenyl diisocyanate were synthesized. Polyamide, polyesteramide from monomer 2 were synthesized. The characterization of these polymers using 1H-NMR, 13C-NMR, solid-state 13C-NMR, IR, GPC, and also thermal analysis are presented. © 1997 John Wiley & Sons, Inc.
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    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 35 (1997), S. 703-708 
    ISSN: 0887-624X
    Keywords: anionic ring-opening polymerization ; poly(ethylene glycol) ; poly(∊-caprolactone) ; poly(D,L-lactide) ; block copolymer ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Poly(D,L-lactide)-poly(∊-caprolactone)-poly(ethylene glycol)-poly(∊-caprolactone)-poly(D,L-lactide) block copolymer (PLA-PCL-PEG-PCL-PLA) was prepared by copolymerization of ∊-caprolactone (∊-CL) and D,L-lactide (D,L-LA) initiated by potassium poly(ethylene glycol)ate in THF at 25°C. The copolymers with different composition were synthesized by adjusting the mole ratio of reaction mixture. The resulted copolymers were characterized by 1H-NMR, 13C-NMR, IR, DSC, and GPC. Efforts to prepare copolymers with the corresponding structure of PCL-PLA-PEG-PLA-PCL and D,L-lactide/∊-caprolactone random copolymers were not successful. © 1997 John Wiley & Sons, Inc.
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  • 14
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    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 35 (1997), S. 727-733 
    ISSN: 0887-624X
    Keywords: titanium tetrachloride ; esterification ; polymer-supported catalyst ; kinetic study ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Crosslinked poly(4-vinylpyridine-co-styrene) was prepared and functionalized with titanium tetrachloride to afford the corresponding poly(4-vinylpyridine-co-styrene)-titanium tetrachloride complex. This insoluble functionalized polymer-supported catalyst shows good catalytic activity for esterification reactions. In this article, the kinetics of esterification of acrylic acid with n-butanol is reported. The rate of formation of product depends on many experimental parameters, viz., stirring speed, concentration of acrylic acid, catalyst amount, temperature, percent active site, percent crosslinking, and mesh size of the polymer catalyst. The reaction rates were found to increase with increase in the stirring speed, concentration of acrylic acid, catalyst amount, and temperature, and decreases with increasing percentage crosslinking and mesh size of the polymer beads. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 727-733, 1997
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  • 15
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    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 35 (1997), S. 759-767 
    ISSN: 0887-624X
    Keywords: oligoetherimide ; cyclic oligomer ; macrocyclic imide ; bisphenol silylether ; fluorophthalimide ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Macrocyclic oligoetherimides were synthesized by means of Kricheldorf's nucleophilic aromatic substitution polycondensation. A solution containing equimolar quantities of bis(trimethylsilyl ether) of bisphenol and arylenebis(fluorophthalimide) was continuously added into a high boiling solvent containing CsF catalyst under a pseudo-high dilution condition. The resulting reaction mixture contained a high yield of cyclic oligomers which could be isolated by solvent extraction. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 759-767, 1997
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  • 16
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    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 35 (1997), S. 879-888 
    ISSN: 0887-624X
    Keywords: polysiloxanes ; cyclosiloxanes ; dimethylsiloxane copolymers ; optically active polymers ; addition to vinylsiloxanes ; ring-opening polymerization ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Polydimethylsiloxanes with part of the siloxane units bearing an optically active sulfoxide group were synthesized. These copolymers had chiral sulfur centres connected to the siloxane chain by a dimethylene bridge. They were obtained mostly by the kinetically controlled anionic ring-opening polymerization of 1-(2-organothioethyl)1,3,3,5,5-pentamethylcyclotrisiloxanes, followed by stereoselective oxidation of prochiral groups to yield partially enantiomeric sulfoxide groups. Sulfoxides bearing cyclic monomers were also used. Polymers were characterized by spectroscopy and polarimetry. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 879-888, 1997
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  • 17
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    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 35 (1997), S. 695-701 
    ISSN: 0887-624X
    Keywords: hypercrosslinked polystyrene ; solids NMR ; structure ; relaxation measurements ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Hypercrosslinked polystyrenes, synthesized by reaction of linear or lightly crosslinked polystyrene with chloromethyl methyl ether (CME) and a Lewis acid in a good solvent, swell even in nonsolvents for polystyrene. Structures and dynamics of hypercrosslinked polystyrenes in both dry solid and solvent-swollen gel states have been determined by 13C-NMR spectroscopy. Deconvolution of 13C solid-state CP/MAS spectra gave the relative numbers of quaternary carbon atoms in monosubstituted and disubstituted benzenes. A typical sample, crosslinked by reaction of a mixture containing 0.5 mol of CME per mol of repeat units, contains 35% of unreacted and 65% of crosslinked aromatic rings, and no residual chloromethyl groups. Gels swollen in CDCl3 and in CH3OH have residual static dipolar interactions enabling crosspolarization and require magic angle spinning (MAS) and high power 1H decoupling to reduce chemical shift anisotropy from ∼ 104 Hz to ∼ 103 Hz. A single proton spin-lattice relaxation time in the rotating frame measured from all peaks in the 13C spectra of dry samples indicates homogeneity on a nanometer scale. Proton NMR line widths indicate no substantial molecular motions in a dry hypercrosslinked polystyrene up to at least 200°C. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 695-701, 1997
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  • 18
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    Journal of Polymer Science Part A: Polymer Chemistry 35 (1997), S. 721-726 
    ISSN: 0887-624X
    Keywords: benzyl α-(alkoxymethyl)acrylate ; stereospecific polymerization ; anionic polymerization ; isotactic polymer ; tacticity ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: α-(Alkoxymethyl) acrylates, such as methyl α-(phenoxymethyl) acrylate, benzyl α-(methoxymethyl)acrylate (BMMA), benzyl α-(benzyloxymethyl)acrylate, and benzyl α-(tert-butoxymethyl)acrylate, were synthesized, and their polymerizability and the stereoregularity of the polymers obtained by radical and anionic methods were investigated. The radically obtained polymers were found to be atactic by 13C- and 1H-NMR analyses, but the polymers obtained with lithium reagents in toluene at -78°C were highly isotactic. Further, it is noteworthy that isotactic polymers were also produced with lithium reagents even in tetrahydrofuran. Effects of polymerization temperature and counter cation on stereoregularity were clearly observed in the polymerization of BMMA, and a potassium reagent afforded an almost atactic polymer. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35:721-726, 1997
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    Journal of Polymer Science Part A: Polymer Chemistry 35 (1997), S. 1013-1021 
    ISSN: 0887-624X
    Keywords: macroporous monoliths ; acrylamide copolymers ; polymerization in mold ; porogens ; polymerization kinetics ; porous properties ; morphology ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Molded macroporous monoliths with pores sizes up to 1000 nm have been prepared by copolymerization of the hydrophilic monomers, acrylamide, and N,N′-methylenebisacrylamide, in the presence of a porogenic diluent. A combination of dimethylsulfoxide and 2-heptanol was selected from a broad spectrum of solvents and water soluble polymers to achieve the optimum composition of the porogenic mixture. In addition to the composition of the porogen the porous properties of the monolithic rods can also be optimized through changes in the percentage of both N,N′-methylene-bisacrylamide (crosslinking monomer) and azobisisobutyronitrile (free radical initiator) used for the polymerization. The hydrophilic monoliths may be used in the separation of biological polymers, solid-phase extraction, or for immobilization of proteins. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35 1013-1021, 1997
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    Journal of Polymer Science Part A: Polymer Chemistry 35 (1997), S. 1047-1059 
    ISSN: 0887-624X
    Keywords: propagating polymerization fronts ; frontal polymerization ; ceiling temperature ; traveling waves ; constant pattern ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Traveling polymerization fronts in unstirred solutions of methylmethacrylate, methacrylic acid, or acrylamide with some free radicals initiators (through thermal decomposition) have been observed experimentally. A local heating of the initial reactant mixture, under suitable conditions, leads to a reaction front that propagates along the space coordinate with a constant velocity. In this article, a physical interpretation of this phenomenon is provided through a mathematical model that accounts for the depolimerization reaction and is based on the constant pattern approach. Moreover, an approximate explicit analytic expression for the velocity of propagation of the polymerization front is proposed. The theoretical values are compared with those measured experimentally as a function of the initiator concentration for different addition polymerization systems. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35:1047-1059, 1997
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    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 35 (1997), S. 1077-1085 
    ISSN: 0887-624X
    Keywords: s-triazine ring ; thermal stability ; polyamide ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Ten new aromatic polyamides containing s-triazine rings in the main chain were synthesized by the low temperature interfacial polycondensation technique involving the reactions of each of the two s-triazine containing diacylchlorides, viz., 2,4-bis (4-chlorocarbonylphenoxy)-6-methoxy-s-triazine and 2,4-bis(3-chlorocarbonylphenoxy)-6-methoxy-s-triazine, with five aromatic diamines namely, 4,4′-bis(4-aminophenoxy)diphenyl sulfone, 4,4′-bis(3-aminophenoxy)diphenyl sulfone, 2,2-bis[4(4-aminophenoxy) phenyl] propane, 1,4 bis (4-amino-phenoxy) benzene, and 1,3-bis (4-aminophenoxy)benzene. The resulting polyamides were characterized by viscosity measurements, IR and 1H-NMR spectroscopy, solubility tests, x-ray diffraction, and thermogravimetry. The polyamides had inherent viscosities in the range of 0.16-1.06 dL/g in N,N-dimethylacetamide at 30°C. Most of the s-triazine containing polyamides dissolved readily at room temperature in polar solvents. Except for the polyamide PA-2, the polyamides did not lose weight below 350°C under a nitrogen atmosphere. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 1077-1085, 1997
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    Journal of Polymer Science Part A: Polymer Chemistry 35 (1997), S. 1133-1137 
    ISSN: 0887-624X
    Keywords: aliphatic linear polycarbonate ; AB polymerization ; cyclohexanediol ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The investigation of a silicon-mediated coupling reaction between hydroxyl and carbonylimidazolide functional groups in the preparation of carbonate linkages is described. Application of this reaction to the formation of aliphatic polycarbonates was accomplished by the polymerization of an AB monomer unit, which was composed of 1,4-cyclohexanediol, where one of the hydroxyl groups was protected as a dimethylphenylsilyl ether and the other carried the carbonylimidazolide functionality. Reaction of this monomer with cesium fluoride removed the silicon protecting group and the resulting alkoxy anion promoted polymerization. Poly(1,4-cyclohexanecarbonate)s with typical molecular weights of Mw = 20,000 and Mn = 7300 a.m.u. (from GPC based upon polystyrene standards) were prepared in ca. 65% yield. The polymer showed a glass transition temperature at 138°C by DSC. TGA gave 85% mass loss between 275 and 350°C. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 1133-1137, 1997.
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    Journal of Polymer Science Part A: Polymer Chemistry 35 (1997), S. 917-925 
    ISSN: 0887-624X
    Keywords: polymer blend ; phase inversion ; compatibilization ; PP-g-MA ; PAmXD,6 ; Brabender torque ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: This work deals with the study of the phase inversion phenomenon in blends of poly(m-xylylene adipamide) and maleic anhydride functionalized polypropylene (PAmXD,6/PP-g-MA blends) processed in a Brabender plastograph at 265 ± 5°C and 45 rpm. The viscosity of the components has been modelized by the Brabender torque and the phase inversion composition was determined by means of a solvent dispersion technique (SDT). The compatibilization, i.e., the amount of copolymer in the blend, does not modify the phase inversion location. The phase inversion composition is determined early during the process and is weakly or even not at all affected by further modification of viscosity ratio of the components versus mixing time. This work demonstrates that the only key parameter of the phase inversion composition is the viscosity ratio of the components at the first stage of the mixing process. An empirical equation linking volume fraction ratio for the phase inversion composition and the square root of the viscosity ratio of the components is proposed. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 917-925, 1997
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    Journal of Polymer Science Part A: Polymer Chemistry 35 (1997), S. 1033-1038 
    ISSN: 0887-624X
    Keywords: ethynyl-substituted monomers ; inorganic monomers ; preceramic monomers ; high-performance thermosets ; thermal analysis ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Monomers 1,3-bis(4-phenylethynylphenyl)tetramethyldisiloxane and 1,7-bis(4-phenylethynylphenyltetramethyldisiloxyl)-m-carborane were synthesized and compared with bis(4-phenylethynylphenyl)dimethylsilane as potential preceramic precursors. These monomers were heated to free flowing liquids above 100°C and thermally polymerized above 300°C to form heat-resistant thermosets or ceramic residues. The ceramic yields for the silane (13%) and siloxane (30%) were much lower than that for the carborane (64%) monomer. The thermoset and ceramic made from the carborane monomer were the best thermally and oxidatively stable materials. After curing, the thermoset had a weight loss of only 6% and after pyrolysis, the ceramic residue had no additional weight loss up to 1000°C in air. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 1033-1038, 1997
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    Journal of Polymer Science Part A: Polymer Chemistry 35 (1997), S. 1023-1031 
    ISSN: 0887-624X
    Keywords: polybisaminophosphazene ; polybisaminophosphazene-silver nitrate complexes ; coordination ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Poly[bis(propylamino)phosphazene]-silver nitrate complexes and poly[bis-(butylamino)phosphazene]-silver nitrate complexes with various salt contents, which are new polyphosphazene-salt complexes, have been prepared. The complexes were characterized by FTIR, 31P-NMR, and 13C-NMR spectroscopies, and the thermal properties were studied by DSC, TGA, and TGA/FTIR measurements. It was found that the poly[(bisamino)phosphazene]-silver coordination may occur both at the backbone nitrogen and the side chain nitrogen and incorporation of silver nitrate into the polymer lowered the decomposition temperature. The complexes can be cast as freestanding film with good dimensional stability. Compared to their parent polymers, the highest conductivities of the films are increased three to four orders in magnitude at room temperature. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 1023-1031, 1997
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    Keywords: naphthalimide ; fluorescence ; structural colored polymer ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Two new unsaturated acryloxide derivatives of 4-amino-substituted-1,8-naphthalimide luminophores were synthesized. Their absorption and fluorescent properties were determined in both CHCl3 and C2H5OH. The luminophores display a broad absorption band in the visible spectral region (halfband-width up to 4433 cm-1) and a fluorescence in the yellow-green region (526-530 nm). The compounds are yellow colored, with a high brightness (from 2.92 up to 6.75) and a purity of color. The possibility of including naphthalimide luminophores in copolymerization process with ST and MMA resulting in the formation of colored polymers was investigated. It was found that no changes in the chemical structure of the chromophore group occurred during copolymerization. More than 92% of the initial luminophores were bound to the polymer chain. The influence of the luminophores on the kinetics of polymerization was studied, and the average viscosimetric molecular weight, Mv, of the obtained colored polymers estimated. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 1069-1076, 1997
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    Journal of Polymer Science Part A: Polymer Chemistry 35 (1997), S. 1125-1132 
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: (5-Ethyl-1,3-dioxane-5-yl) methyl acrylate (HEDA) and (5-ethyl-1,3-dioxane-5-yl)methyl methacrylate (HEDMA) were synthesized by reaction between acryloyl and methacryloyl chloride with 5-ethyl, 5-hydroxymethyl, 1,3-dioxane. The kinetics of the polymerization of both are studied at different temperatures in benzene solution. Dilatometric techniques and nonlinear least-squares methods were used to obtain the kinetic data and to determine the kinetic constants, respectively. The values of kp/k1/2t for the acrylic and methacrylic monomers are higher than those corresponding to methyl acrylate and methyl methacrylate, respectively. Important changes in kp/k1/2t with temperature occur in the polymerization of HEDA, and the corresponding Arrhenius plot gives an activation energy of 5.6 kcal mol-1. On the contrary, only slight changes with temperature are observed in this ratio for HEDMA and the activation energy associated with the polymerization reaction is ca. 1.7 kcal mol-1. The stereo-structure of both polymers was determined by 13C-NMR spectroscopy and the molar fractions of tactic dyads, triads (and in the case of the methacrylic polymer also pentads) were determined from different resonance signals. Finally, the glass transition temperatures of both PHEDA and PHEDMA are 33 and 123°C, respectively. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 1125-1132, 1997
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    Journal of Polymer Science Part A: Polymer Chemistry 35 (1997), S. 1167-1172 
    ISSN: 0887-624X
    Keywords: deoxygenation ; polyperoxides ; biphile ; concerted insertion ; NMR spectroscopy ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The triphenylphosphine deoxygenation of the polyperoxides, poly(styrene peroxide), poly(methyl methacrylate peroxide), and poly(α-methylstyrene peroxide) proceed via the phosphorane intermediates, which in the presence of moisture hydrolyze to give the respective diols. At higher temperatures and under dry conditions the phosphorane decomposes into epoxide and triphenylphosphine oxide. The reaction has been studied by 1H-, 13C-, and 31P-NMR spectroscopy. The results obtained are consistent with a concerted insertion of the biphile, triphenylphosphine, into the peroxy bond and this reaction pathway seems to be new as far as the chemistry of polyperoxides is concerned. Though the aim of this investigation was to test the selective deoxygenation of polyperoxide by triphenylphosphine as a method of preparing polyethers, it turned out to be a fruitful method of synthesis of stereospecific diols. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 1167-1172, 1997
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    Journal of Polymer Science Part A: Polymer Chemistry 35 (1997), S. 1149-1155 
    ISSN: 0887-624X
    Keywords: poly(amide-imide)s ; polyimides ; copolymers ; selective reduction of aromatic nitro groups ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The synthesis of N,N′-bis(4′-amino-4-biphenylene) isophthalamide (BABPI) and its applicability as a new diamine for the preparation of a series of new, high Tg, perfectly alternating poly(amide-imide)s is described. BABPI was synthesized from the catalytic reduction of the corresponding dinitro compound which was prepared by the condensation of isophthaloyl chloride and 4-amino-4′-nitrobiphenyl. The modified selective reduction technique was used for the preparation of 4-amino-4′-nitrobiphenyl from 4,4′-dinitro-biphenyl. Poly(amide-imide)s were synthesized by polycondensation of diamine BABPI with various commercially available aromatic dianhydrides via a conventional two-step procedure. In the first step, poly(amic-acid)s were prepared in a polar aprotic solvent, such as N-methyl pyrrolidone (NMP) at room temperature. Depending on the dianhydride used, intrinsic viscosities of poly(amic-acid)s were found to range between 0.43-0.69 dL/g. Bulk thermal imidization technique was used to obtain fully imidized poly(amide-imide)s at the second step. The synthesized poly(amide-imide)s showed good thermal stability up to 320°C and the 10% weight loss temperatures were recorded in the range of 525-550°C as evidenced by thermogravimetric analysis (TGA). The glass transition temperatures were found to be between 225-235°C from differential scanning calorimeter (DSC) measurements. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 1149-1155, 1997
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    Journal of Polymer Science Part A: Polymer Chemistry 35 (1997), S. 1197-1210 
    ISSN: 0887-624X
    Keywords: poly(ethylenimine) ; Fe(III) sequestration ; crosslinkage ; effective molarity ; 5-(bromoacetyl) salicylic acid ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Three molecules of 5-(bromoacetyl) salicylate (1) complexed to Fe(III) ion were crosslinked with poly(ethylenimine) (PEI) in DMSO by alkylation of amino groups of PEI with 1, leading to the formation of Fe(Sal)3PEI, a water-soluble polymer. Several other derivatives including the immobilized form were also prepared. Examination of the values of log Kf for the PEI derivatives indicated that each Fe(III) binding site in Fe(Sal)3PEI contains three salicylate moieties. In addition, the log Kf revealed that the effective molarity (EM) of the salicylate groups contained in the Fe(III) binding site is ca. 1000M. The high EM value shows that the geometry of the coordination sphere is well conserved during the crosslinkage with PEI of 1 preassembled around Fe(III) ion. In view of the EM value and the pKa values of salicylic phenols in apo(Sal)3-PEI, the metal-free form, the three salicylate groups of each Fe(III) binding site appear to occupy proximal positions leading to effective cooperation in Fe(III) binding. Fast, strong, and selective binding of Fe(III) ion by the binding site comprising three salicylate moieties was demonstrated. In addition, rapid demetalation of the resulting complexes as well as chemical stability of the immobilized chelating agents built on PEI were achieved. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 1197-1210, 1997
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    Journal of Polymer Science Part A: Polymer Chemistry 35 (1997), S. 1211-1218 
    ISSN: 0887-624X
    Keywords: three-component polycondensation ; π-allylpalladium complex ; bisallene ; aryl dihalides ; nucleophiles ; palladium catalyst ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A novel palladium-catalyzed three-component polycondensation of 1,2,10,11-dodecatetraene, 4,4′-diiodobiphenyl, and nucleophiles was carried out using various carbanions and amines as a nucleophilic part. The polymerization with various sodium diethyl malonates produced polymers in high yields. Particularly, no exo-double bond was detected in the polymers prepared from sodium diethyl malonates bearing substituents directly on the carbanion center. The ratios of E- and Z- isomeric units in the polymers were dependent on the structure of the nucleophiles used. Other carbanions with appropriate electron-withdrawing groups such as sulphones and ketones can be also used as a nucleophile for the present polycondensation. Within heteronucleophiles examined, cyclic amines were suitable to produce polymers in high yields. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 1211-1218, 1997
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    Journal of Polymer Science Part A: Polymer Chemistry 35 (1997), S. 1219-1226 
    ISSN: 0887-624X
    Keywords: quaternization ; poly(tertiary aminostyrene)s ; Menschutkin reaction ; N,N-dimethylamino group ; adsorption on GPC gel ; water-soluble polymers ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The Menschutkin reaction of three poly(tertiary aminostyrene)s: poly(N,N-dimethyl-4-vinylphenylamine) (PPA), poly(N,N-dimethyl-4-vinylbenzylamine) (PBA), and poly(N,N-dimethyl-4-vinylphenethylamine) (PPTA) was investigated. These three polymers having narrow molecular weight distributions were prepared via anionic living polymerization. PPA reacted homogeneously with n-butyl bromide in N,N-dimethylformamide (DMF). PBA and PPTA also reacted homogeneously with n-butyl bromide in a mixture of DMF/methanol (75/25 v/v %). GPC measurement of the quaternized polymers was carried out using a mixture of water/acetonitrile (80/20 v/v %) containing 0.5M acetic acid and 0.3M sodium sulfate (pH = 2.9) as an eluant in order to suppress adsorption of the quaternized water soluble polymers on GPC gel. Results of GPC measurement indicate that the polymer chains of the three poly(tertiary aminostyrene)s are neither severed nor crosslinked in the process of quaternization. Temperature dependence and reaction time dependence on the degree of quaternization (DQ) were studied for PPT, PBA, and PPTA. By altering reaction time and temperature, the DQ values of the three poly(tertiary aminostyrene)s could be controlled in the range from 0% to nearly 100%. Quaternization reactivity of the amino groups in the three polymers was found to decrease in the order, PPTA, PBA, and PPA. The differences in reactivity are thought to be attributable to the electron density on the nitrogen atom of the N,N-dimethylamino group, and steric hindrance in the vicinity of the nitrogen atom. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 1219-1226, 1997
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    Journal of Polymer Science Part A: Polymer Chemistry 35 (1997), S. 1237-1244 
    ISSN: 0887-624X
    Keywords: polyurethane ionomers ; iniferters ; “living” radical polymerization ; tetraphenylethane derivatives ; vinylbenzyl chloride ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Polyurethane iniferter prepared from isocyanate end capped prepolymer and 1,1,2,2-tetraphenyl-1,2-ethanediol, has been used to polymerize vinylbenzyl chloride to obtain polyurethane-polyvinylbenzyl chloride multiblock copolymers. Formation of the block copolymers proceeds with increase in both molecular weight and conversion with increasing polymerization time showing that the polymerization proceeds via a “living” radical mechanism. The block copolymers so obtained were converted into their cationomers by the treatment of triethylamine. The block copolymers and their cationomers have been characterized by FTIR, FTNMR, TGA, and DSC studies. The effect of thermal energy on the molecular weight of the macroiniferter in the absence of monomer has been studied in order to understand the mechanism of formation of the block copolymers. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 1237-1244, 1997
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    Journal of Polymer Science Part A: Polymer Chemistry 35 (1997), S. 1245-1254 
    ISSN: 0887-624X
    Keywords: cyanate ; 13C-NMR ; chromatographics ; Epscysl ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Using differential scanning calorimetry, we have investigated three difunctional cyanate monomers differing by their central group: bisphenol A dicyanate (BADCy), bisphenol E dicyanate (BEDCy), and hexafluorinated bisphenol A dicyanate (BAFDCy), to determine the effect of the central group on the molten state reactivity of heat-treated cyanates. To identify the different phenomena occurring during the heat cycle, which was followed by differential scanning calorimetry, 13C-NMR (liquid and solid) was undertaken. This technique was used to characterize the major products and side products formed. Using 13C-NMR and HPLC, we were able to detect the formation of compounds with a triazine ring at one chain end and a hydroxyl function at the other. The presence of the latter depended on the purity of the initial monomers. In light of the purity parameter, inherent in the synthesis of the products, we propose an order of reactivity, at molten state, of the polymerization of the three cyanate monomers in the temperature range of 180-300°C. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 1245-1254 1997
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    Journal of Polymer Science Part A: Polymer Chemistry 35 (1997), S. 1265-1273 
    ISSN: 0887-624X
    Keywords: ruthenium ; samarium ; polyaddition ; dialdehydes ; polyester ; Tishchenko type reactions ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: RuH2(PPh3)4 catalyzed Tishchenko type polyaddition of terephthal-aldehyde gives aromatic polyester (1), which contains three structural units, [OCH2—C6H4—CH2O] (1a), [OCH2—C6H4—CO] (1b), and [CO—C6H4—CO] (1c). 1H-NMR spectrum shows the presence of the three units in a 1 : 2 : 1 ratio. Isophthalaldehyde also undergoes similar polyaddition to give another aromatic polyester (2), while 1,12-dodecanedial gives an aliphatic polyester (3) containing the following structural units: [OCH2—(CH2)10—CH2O] (3a), [OCH2—(CH2)10—CO] (3b), and [CO—(CH2)10—CO] (3c). The above polymers have Mn of 2.7 × 103-5.4 × 103 and Mw of 4.3 × 103 - 9.7 × 103, respectively. Mixtures of terephthalaldehyde and 1,12-dodecanedial produce copolymers, which contain the units 1a-1c and 3a-3c in a random sequence. In the copolymerization, terephthalaldehyde shows a strong tendency to give 1c units, whereas 1,12-dodecanedial predominantly affords 3a units. SmI2 also catalyzes polyaddition of terephthalaldehyde to give the corresponding polyester with Mn of 1.7 × 103 and Mw of 3.7 × 103, respectively. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 1265-1273, 1997
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    Journal of Polymer Science Part A: Polymer Chemistry 35 (1997), S. 1283-1291 
    ISSN: 0887-624X
    Keywords: palladium catalyst ; styrene-carbon monoxide copolymer ; alternating copolymerization ; photodegradation ; thermodegradation ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A series of styrene derivatives were synthesized from aromatic substances by Friedel-Crafts acylation, reduction, and dehydration. Alternating copolymers of styrene derivatives and carbon monoxide were prepared in the presence of a palladium(II) catalyst. The characterization of the polyketones produced was performed by use of 1H-NMR, IR, WXRD, and EA methods. The thermal degradation of the regular alternating copolymer of carbon monoxide and styrene (STCO) has been studied by thermal gravimetry (TG). The TG spectra of solid samples were recorded both in nitrogen and in air. The degradation reaction order and activation energy were determined. The photodegradation of STCO was investigated. In addition, the block copolymerization of STCO with methyl methacrylate under UV irradiations was also studied. It is found that the tertiary amine can promote this photopolymerization. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 1283-1291, 1997
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    Journal of Polymer Science Part A: Polymer Chemistry 35 (1997), S. 1303-1311 
    ISSN: 0887-624X
    Keywords: polyimides ; cyano-substituted polymers ; synthesis ; crosslinking ; thermal stability ; 2,3-dicyanopyrazine ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: New crosslinkable aromatic polyimides were synthesized from 2,3-dicyano-5,6-di(aminophenyl)pyrazine (1b) and 2,3-dicyanopyrazino [5,6-9,10] diaminophenanthrene (2b). They were characterized by viscosimetry, IR, NMR, x-ray, DTA, TMA, TGA, and isothermal gravimetric analysis. The polyimides derived from 1b were amorphous whereas those prepared from 2b showed microcrystalline or crystalline character. The polymers were soluble in polar aprotic solvents (DMF, NMP, DMSO) at ambient temperature or upon heating. They dissolved also completely or partially in certain hot inorganic and organic acids (H2SO4, CCl3COOH). Their glass transition temperatures were in the range of 257-370°C. The crosslinked polymers obtained after an appropriate thermal treatment, were stable up to 397-426°C in N2 or air and afforded anaerobic char yields of 62-75% at 800°C. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 1303-1311, 1997
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    Journal of Polymer Science Part A: Polymer Chemistry 35 (1997), S. 1891-1900 
    ISSN: 0887-624X
    Keywords: radical polymerization ; steric effect ; ESR spectrum ; MALDI-TOF mass spectrum ; propagation rate constant ; termination rate constant ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The polymerization of benzyl N-(2,6-dimethylphenyl)itaconamate (BDMPI) with benzoyl peroxide (BPO) in N,N-dimethylformamide (DMF) was studied kinetically by ESR. The polymerization rate (Rp) at 70°C was given by Rp = k[BPO]0.78[BDMPI]1.1. The overall activation energy of polymerization was determined to be 83.7 kJ/mol. The number-average molecular weight of poly(BDMPI) was in the range of 1500-2000 by gel permeation chromatography. From the ESR study, the polymerization system was found to involve ESR-observable propagating radicals of BDMPI under practical polymerization conditions. Using the polymer radical concentration by ESR, the rate constants of propagation (kp) and termination (kt) were determined in the temperature range of 50-70°C. The kp value seemed dependent on the chain-length of propagating radical. The analysis of polymers by the MALDI-TOF mass spectrometry suggested that most of the resulting polymers contain the dimethylamino terminal group. The copolymerization of BDMPI (M1) and styrene (M2) at 50°C in DMF gave the following copolymerization parameters; r1 = 0.49, r2 = 0.26, Q1 = 1.2, and e1 = +0.63. The thermal behavior of poly(BDMPI) was examined by dynamic thermogravimetry and differential scanning calorimetry. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 1891-1900, 1997
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    Journal of Polymer Science Part A: Polymer Chemistry 35 (1997), S. 1873-1889 
    ISSN: 0887-624X
    Keywords: free-radical polymerization ; kinetics ; hydrogel ; thermoset ; crosslinking ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: An experimental study was carried out to investigate the effect of ethylene glycol dimethacrylate (EGDMA, as a crosslinking agent) content on the curing kinetics of the polymerization of 2-hydroxyethyl methacrylate (HEMA), using differential scanning calorimetry (DSC) and Fourier transform infrared spectroscopy (FTIR). EGDMA may cause a crosslinking-facilitated gel effect which reduces the termination rate of living free radicals and enhances the overall reaction rate, but it may also induce a diffusional resistance for the reactants so that some free monomers are trapped and pendant vinyl groups are prohibited from reaction by the crosslinked structure. At higher content of EGDMA, the later effect becomes predominant, and the reaction rate and the final conversion are limited. The exothermic peak of the curing reaction tends to carry a shoulder and then split into two peaks as the amount of EGDMA is increased, possibly due to a later reaction of the trapped monomers and pendant vinyls. The heat of reaction measured by DSC in the scanning mode is 61.2 kJ/mol C=C. The activation energy (E) of the curing reaction ranges from 56.5 to 78.3 kJ/mol C=C depending on the EGDMA content and the type of operation. The diffusion-limited reaction rate and the different thermal history experienced in the nonisothermal and isothermal curing can result in variations of the results in the activation energy measurement. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 1873-1889, 1997
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    Journal of Polymer Science Part A: Polymer Chemistry 35 (1997), S. 1933-1938 
    ISSN: 0887-624X
    Keywords: amino-containing polymers ; water-soluble polymers ; polymer salts ; ionically bonded, physiologically active polymers ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The preparation of water-soluble polymers with physiological activity via ion bonding of low molecular weight physiologically active substances to a polymer carrier has been studied. The conditions for obtaining polymer salts of physiologically active substances with acid properties and amino-containing polymer carrier have been established. The maximum conversion degree has been determined. The polymer salts have been characterized by potentiometric titration, 31P-NMR and IR spectroscopy, and elemental analysis. The stability of the salts and the immobilization rate of the low molecular weight physiologically active substances have been investigated. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 1933-1938, 1997
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    Journal of Polymer Science Part A: Polymer Chemistry 35 (1997), S. 1949-1954 
    ISSN: 0887-624X
    Keywords: MU solvents ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: An alcoholic-aqueous solution of LiBr·H2O is a useful solvent for silk fibroin, if the ratio of alcohol content to water content therein is 1 or more. The mixed solvents consisting of ethanol, water, and LiBr·H2O showed a higher solubility if they contained a lesser amount of water. They further proved able to easily dissolve more than 20% by weight of silk fibroin. Solvents poorer in water content and richer in LiBr·H2O showed a higher value of [η]; Huggins' coefficient of said solutions varied within a range 0.5-1.0, the minimum appearing at a water content of about 10% weight. Fibroin molecules remained stable in those solutions. The novel solvents for silk fibroin that have been developed by us are named “MU solvents,” by taking the initials in the names of Matumoto/Uejima. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 1949-1954, 1997
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    Journal of Polymer Science Part A: Polymer Chemistry 35 (1997), S. 1967-1972 
    ISSN: 0887-624X
    Keywords: thermosensitive ; redox-active polymer ; ferrocene ; LCST ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Thermosensitive and redox-active polymers were prepared by copolymerization of N-ethyl- or N,N-diethylacrylamides with vinylferrocene (VFc). LCST (lower critical solution temperature) of the aqueous copolymer solution was decreased by increasing the ferrocene content in the copolymer. The oxidation of ferrocene led to a significant increase in LCST due to the transition from hydrophobic to hydrophilic character of the ferrocene moiety in the copolymer. The ferrocene content in the copolymer increases with increasing differences between the LCST's of the oxidation and reduction states. The transition could be made reversible by redox reaction using L-ascorbic acid as an oxidant and cerium sulfate as a reductant. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 1967-1972, 1997
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    Journal of Polymer Science Part A: Polymer Chemistry 35 (1997), S. 1999-2007 
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The syntheses of random and block copolymers (using sequential monomer addition) of methyl methacrylate (MMA) and lauryl methacrylate (LMA) have been investigated by group transfer polymerization (GTP) over a wide composition range using tetrabutylammonium bibenzoate (TBABB) as catalyst and 1-methoxy-1-(trimethylsiloxy)-2-methyl-1-propene (MTS) as initiator in tetrahydrofuran (THF) at room temperature. The absolute molecular weight of the copolymers were determined by SEC-MALLS. The observed molecular weights were generally higher than the calculated molecular weights. However, the molecular weight distributions were very narrow (1.02-1.1). Use of trimethylsilyl benzoate as a “livingness enhancer” improved the livingness of the first block (PLMA) and block copolymers with no detectable contamination of homopolymer. Statistical copolymers of MMA and LMA were prepared, and the reactivity ratios of the two monomers under the defined conditions were determined. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 1999-2007, 1997
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    Journal of Polymer Science Part A: Polymer Chemistry 35 (1997), S. 2009-2013 
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Dispersion polymerizations of methyl methacrylate utilizing poly(1,1,-dihydroperfluorooctyl acrylate) as a steric stabilizer in supercritical carbon dioxide (CO2) were carried out in the presence of helium. Particle size and particle size distribution were found to be dependent on the amount of inert helium present. Particle sizes ranging from 1.64 to 2.66 μm were obtained with various amounts of helium. Solvatochromic investigations using 9-(α-perfluoroheptyl-β,β-dicyanovinyl)julolidine indicated that the solvent strength of CO2 decreases with increasing helium concentration. This effect was confirmed by calculations of Hildebrand solubility parameters. Dispersion polymerization results indicate that PMMA particle size can be attenuated by the amount of helium present in supercritical CO2. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 2009-2013, 1997
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    Journal of Polymer Science Part A: Polymer Chemistry 35 (1997), S. 1535-1541 
    ISSN: 0887-624X
    Keywords: cyclodextrin gel ; poly(N-isopropylacrylamide) ; anilinonaphthalenesulfonic acid ; temperature responsiveness ; stereoselectivity ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: β-Cyclodextrin (CD) gels crosslinked by epichlorohydrin (CD-gel) were modified with poly(N-isopropylacrylamide) (PIPA; Mn 4900) chains. The CD residue in the gel associated with 8-anilino-1-naphthalenesulfonic acid (ANS) more strongly than the free PIPA-carrying CD. The van't Hoff plot for complexation of ANS with the gel drifted largely from linear relationship above the coil-globule transition temperature of individual PIPA chains. Furthermore, a relatively more significant temperature effect on the stereoselective adsorption of phenylalanine to the CD gel was observed by the modification with PIPA chains. These results imply that the ability of the CD-gel-PIPA conjugate to form inclusion complex could be skillfully controlled by temperature. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 1535-1541, 1997
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    Journal of Polymer Science Part A: Polymer Chemistry 35 (1997), S. 1909-1924 
    ISSN: 0887-624X
    Keywords: poly(benzobisthiazole) ; poly(benzobisoxazole) ; triphenylamine derivatives ; conducting polymers ; iodine doping ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Thermally stable, nonrigid-rod poly(benzobisthiazoles), (R)TPA-PBZT, where R = H, Me, NMe2, and OH, and poly(benzobisoxazoles), (R)TPA-PBO, where R = Me, NMe2 containing electron-rich triarylamine groups with various para-substituents (Rs) on the pendent phenyl ring, were synthesized from either 2,5-diamino-1,4-benzenedithiol dihydrochloride or 2,4-diamino-1,5-benzenediol dihydrochloride and the respective triarylamine-based dinitrile or diacid monomer in polyphosphoric acid. Whereas (R)TPA-PBZT polymers were obtained in moderate molecular weights, analogous (R)TPA-PBO polymers were only prepared in low molecular weights. No lyotropic behaviors, characteristic of the unmodified rigid-rod benzazole polymers, as evidenced by the absence of either stir opalescence or birefringence under crosspolarizers, were observed for these homopolymers at about 10 wt % polymer concentration. Among these polymers, only (Me)TPA-PBZT and (NMe2)TPA-PBZT formed cast films with good mechanical integrity. In their pristine state, their film conductivity values were in the range of 10-10-10-9 S/cm at room temperature. Upon exposure to iodine vapor, their conductivities were increased to the maximal values of 5.0 × 10-5 S/cm ((Me)TPA-PBZT) and 4.1 × 10-4 S/cm ((NMe2)TPA-PBZT). © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 1909-1924, 1997
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  • 47
    ISSN: 0887-624X
    Keywords: photosetting polycarbonates ; isosorbide ; 4,4′-dihydroxychalcone ; cholesteric phase ; Grandjean texture ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Numerous polycarbonates were prepared by means of “diphosgene” in pyridine using hydroquinone 4-hydroxybenzoate (HQHB) as mesogenic diphenol. In addition to the homopolycarbonate, binary copolycarbonates of HQHB and 4,4′-dihydroxychalcone (DHC) with varying molar composition were prepared. A series of ternary copolycarbonates were obtained by incorporation of isosorbide. Furthermore, an alternating copolycarbonate of HQHB and isosorbide was synthesized. All polycarbonates were characterized by inherent viscosities, elemental analyses, IR-, 1H-NMR, and 13C NMR spectroscopy, by WAXS powder patterns DSC measurements, and optical microscopy with crossed polarizers. The homopolycarbonate of HQHB and most binary copolycarbonates were semicrystalline materials forming an enantiotropic nematic melt. Particularly noteworthy is the finding that the alternating copolycarbonate of HQHB and isosorbide forms a broad cholesteric phase despite the unfavorable stereochemistry of isosorbide. The ternary copolycarbonates containing isosorbide formed a cholesteric melt and a Grandjean texture upon shearing. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 1611-1619, 1997
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    Journal of Polymer Science Part A: Polymer Chemistry 35 (1997), S. 1659-1672 
    ISSN: 0887-624X
    Keywords: butyl acrylate ; methyl methacrylate ; vinyl acetate ; terpolymerization kinetics ; emulsion polymerization ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A systematic study of the terpolymerization of butyl acrylate/methyl methacrylate/vinyl acetate (BA/MMA/VAc) was conducted. In this stage of the study, batch emulsion terpolymerizations were performed in a 5 L stainless steel pilot plant reactor. The experiments were designed using a Bayesian (optimal) technique. The polymers produced were characterized for conversion, composition, molecular weight, and particle size. Conversion, terpolymer composition, number- and weight-average molecular weight, and average particle size results are discussed in light of the influence of seven factors and the interaction of these factors. The factors studied include monomer feed composition, initiator concentration, chain transfer agent concentration, impurity concentration, initiator type, emulsifier concentration, and temperature. A “two-stage rate” phenomenon, similar to that occurring in bulk co- and terpolymerization and emulsion copolymerization of acrylic/vinyl acetate systems was observed in the conversion, composition and molecular weight data. Furthermore, an interesting yet often ignored effect of impurities on emulsion polymerization kinetics was explained. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 1659-1672, 1997
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    Journal of Polymer Science Part A: Polymer Chemistry 35 (1997), S. 1689-1701 
    ISSN: 0887-624X
    Keywords: polyisobutylene ; photooxidation ; thermooxidation ; FTIR spectrometry ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Polyisobutylene films (PIB) were submitted to a thermal oxidation at 100°C and to a photooxidation by exposure to long-wavelength radiations (λ ≥ 300 nm) at 60°C. The modifications of the chemical structure resulting from the oxidation were determined by FT-IR analysis of the polymer films, coupled to chemical treatments that converted specifically the oxidation products. Dissolution of oxidized samples permitted analysis of the polymer by 13C- and 1H-NMR. The structure of the volatile products was determined by mass spectroscopy analysis of the gas phase. Identification of the numerous products formed permitted the proposal of a scheme that accounts for the oxidation of PIB. When the irradiations are carried out at a temperature above 50°C, the depolymerization is favored and the mechanism involves two main routes of oxidation. A direct oxidation starts with the oxidation of radicals obtained by homolysis of the C—C bonds on the main chain, and an induced oxidation involves hydrogen abstraction on the methylene and methyl groups by radicals formed by the direct oxidation of the polymer. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 1689-1701, 1997
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    Journal of Polymer Science Part A: Polymer Chemistry 35 (1997), S. 2167-2176 
    ISSN: 0887-624X
    Keywords: polyradicals ; magnetism ; polyacetylene ; polyphenylacetylene ; molecular magnetism ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A photochemical precursor to a pendant conjugated polyradical has been synthesized, poly[3,5-di-tert-butyl-4-[(2,4,6-tri-tert-butylphenyl)oxalato]phenylacetylene], 3. Irradiation of 3 at 77 K in the solid state at 〈 300 nm yielded poly(3-5-di-tert-butyl-2-oxyphenyl acetylene), 2, with 30-40% of the expected number of radical spins. Spin yields on the surface of solid samples appears to be considerably higher. Electron spin resonance experiments showed no evidence of cooperative exchange interaction between the pendant spins. Computational modeling indicated that a major reason for the failure of this and other polyphenylacetylenes to show ferromagnetic exchange between spins is the substantial twisting of the polyacetylene backbone required by steric interactions, leading to deconjugation and a loss of exchange interaction between pendant radicals along the chain. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 2167-2176, 1997
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    ISSN: 0887-624X
    Keywords: polysiloxanes ; liquid crystalline polymers ; lateral substitution effect ; thermal stimulated current ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The synthesis of side-chain liquid crystalline polysiloxanes containing either 4-[(S)-2-methyl-1-butoxy]phenyl 4-(alkenyloxy)benzoate or laterally fluoro-, chloro-, bromo-, and methoxy-substituted 4-[(S)-2-methyl-1-butoxy]phenyl 4-(alkenyloxy)benzoate mesogenic side groups is presented. The mesomorphic properties of the synthesized polymers have been characterized by optical polarizing microscopy, differential scanning calorimetry, and X-ray diffraction measurements. The effects of spacer length and lateral substituent on the mesomorphic properties of the obtained polymers are examined. The five polymers which contain three methylene units in the spacers show no mesophase, while the five polymers which contain eleven methylene units in the spacer display smectic mesomorphism. Among the other fifteen polymers which contain respectively four, five, or six methylene units in the spacers, those with small fluoro and chloro substituents reveal respectively an SA phase, while those with bulky bromo and methoxy substituents show no liquid crystalline behavior. The experimental results demonstrate that introducing a bulky lateral substituent into the mesogenic core of a polymer depresses the tendency to form a mesophase. Furthermore, the technique of thermally stimulated current has been used to study the dipolar relaxation mechanisms in a side-chain liquid crystalline polysiloxane. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 2793-2800, 1997
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    Journal of Polymer Science Part A: Polymer Chemistry 35 (1997), S. 2801-2809 
    ISSN: 0887-624X
    Keywords: spirobichroman ; diether anhydride ; poly(ether imide)s ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A spirobichroman structure-containing diether anhydride (SBCDA), 6,6′-bis(3,4-dicarboxyphenoxy)-4,4,4′,4′,7,7′-hexamethyl-2,2′-spirobichroman dianhydride, was prepared by the nucleophilic nitrodisplacement of 4-nitrophthalonitrile with the phenolate ion of 6,6′-dihydroxy-4,4,4′,4′,7,7′-hexamethyl-2,2′-spirobichroman, followed by alkaline hydrolysis of the intermediate tetranitrile and dehydration of the resulting tetraacid. A series of high molecular weight poly(ether imide)s with inherent viscosities between 0.45 and 1.28 dL/g were synthesized from SBCDA and various aromatic diamines via a conventional two-stage procedure that included ring-opening polyaddition in N,N-dimethylacetamide (DMAc) to give poly(amic acid)s, followed by thermal cyclization to poly(ether imide)s. The intermediate poly(amic acid)s had inherent viscosities of 0.70-1.50 dL/g. Except for the poly(ether imide) obtained from p-phenylenediamine, the other poly(ether imide)s were soluble in various organic solvents and could be solution-cast into transparent, flexible, and tough films. These poly(ether imide)s had glass transition temperatures in the range 175-262°C and showed no significant decomposition below 420°C, with 10% weight loss being recorded above 446°C in nitrogen or air. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 2801-2809, 1997
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    Journal of Polymer Science Part A: Polymer Chemistry 35 (1997), S. 2813-2819 
    ISSN: 0887-624X
    Keywords: styrene ; 2-vinyldibenzothiophene ; radical polymerization ; radical copolymerization ; monomer reactivity ratio ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A monomer having dibenzothiophene moiety, 2-vinyldibenzothiophene (1), was prepared by the Ni-catalyzed cross-coupling reaction of vinyl bromide with the Grignard reagent of 2-bromodibenzothiophene. The radical homopolymerization of 1 and the copolymerization with styrene were carried out at 60°C in toluene (1.0M) for 20 h using AIBN (5 mol %) as an initiator to obtain the corresponding polymers in high yields. Thermal analyses of the copolymers showed that both 10% weight loss and glass transition temperatures increase when increasing the content of 1 unit. The monomer reactivity ratio was evaluated as r1 = 2.55 (1) and r2 = 0.16 (styrene). © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 2813-2819, 1997
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    Journal of Polymer Science Part A: Polymer Chemistry 35 (1997), S. 2821-2825 
    ISSN: 0887-624X
    Keywords: end-capped polyester ; SmI2 ; Tishchenko-type polyaddition ; dialdehydes ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: SmI2-catalyzed polyaddition of 1,12-dodecanedial followed by treatment with benzaldehyde gives a polyester (1) containing three structural units, [OCH2—(CH2)10—CH2O], [OCH2—(CH2)10—CO], and [CO—(CH2)10—CO], in the main chain and an OCH2Ph end-capping group. GPC analysis of 1 shows molecular weights of Mn = 5.5 × 103 and Mw = 14 × 103. The 1H-NMR spectrum reveals the polymer structure with the COOCH2Ph end group as well as the Mn value (2.6 × 103) calculated based on an amount of the end-capping group and lower than that estimated from GPC. Mixtures of terephthalaldehyde and 1,12-dodecanedial in several molar ratios undergo similar polyaddition catalyzed by SmI2 to give the corresponding copolyesters after treatment with benzaldehyde. Increase in the ratio of 1,12-dodecanedial causes increase in yield and molecular weight of the copolymer. Terephthalaldehyde shows a tendency to give alcohol-side —O—R—O— unit in the polyester, whereas 1,12-dodecanedial is mostly incorporated as the acid-side —CO—R′—CO— unit. Terminal aldehyde group derived from dodecanedial is capped effectively by benzaldehyde to give the COOCH2Ph end group. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 2821-2825, 1997
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    Journal of Polymer Science Part A: Polymer Chemistry 35 (1997), S. 2827-2833 
    ISSN: 0887-624X
    Keywords: poly(divinylsiloxyethylene glycol) ; PVSE ; polycondensation ; electron-beam resist ; lower critical solution temperature (LCST) ; hydrolytic stability ; oxygen reactive ion etching (O2 RIE) resistance ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Poly(divinylsiloxyethylene glycol), which consists of alternating oligo(ethylene glycol)s (MW = 300) and divinylsiloxanes were prepared by a polycondensation reaction (Mn = 6500-9300, Mw/Mn = 2.01-2.27). The obtained polymer (PVSE300) showed a lower critical solution temperature (LCST) at 10.5°C, meaning that the polymer was soluble in water below the LCST. The glass transition temperature (Tg) and onset temperature of degradation (Td) of the PVSE300 were -72.5 and +317.5°C, respectively. The hydrolytic stability of the PVSE300 in aqueous media was also examined and it was found that PVSE300 was fairly stable in cold water. The lithographic characteristics of PVSE300 were examined against UV and electron-beam (EB) exposure and it was found that the PVSE300 film showed a negative character when developed by cold water. The photosensitivity parameter, Dg50, which denotes the dose at half remaining film thickness after development, against EB exposure was extremely high (1.0 μC/cm2) when a probe current and an accelerating voltage was 100 pA and 20 kV, respectively. A high durability for O2 reactive ion etching (O2 RIE) was also observed. The characteristics of PVSE300 against photoirradiation were also examined. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 2827-2833, 1997
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    Journal of Polymer Science Part A: Polymer Chemistry 35 (1997), S. 2835-2842 
    ISSN: 0887-624X
    Keywords: N,N′-aliphatic dicarboxyl bis(hydrazones) ; N - N-bonded polymers ; epoxy resins ; propellant binders ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A new class of epoxy resins having N - N bonds in their structure has been synthesized by reacting N,N′-aliphatic dicarboxyl bis(hydrazones) (the aldehyde/ketone derivatives of malonic, adipic, and sebacic dihydrazides) with epichlorohydrin. The reactivity of the \documentclass{article}\pagestyle{empty}\begin{document}$ ^{\backslash }_{/}\hbox{NH} $\end{document} protons as a function of the substituent group and the number of methylene spacer groups present in the hydrazone has been examined. The resins obtained have been characterized by elemental and epoxy equivalent analyses and IR and NMR spectra. All these resins are found to have adequate viscosity and cure easily with amine curatives at elevated temperatures. Relevant properties for their use as binders in propellant formulations, such as thermal stability, heat of combustion, density, temperature-dependence of viscosity, and mechanical strength of the composites, have been evaluated. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 2835-2842, 1997
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    Journal of Polymer Science Part A: Polymer Chemistry 35 (1997), S. 2857-2864 
    ISSN: 0887-624X
    Keywords: aldehyde separation ; polymeric sulfonamides ; polymer with oligo(ethyleneimines) ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Chlorosulfonated styrene (10%) divinylbenzene resin beads reacted with an excess of ethylenediamine (EDA), diethylenetriamine (DETA), and triethylenetetramine (TETA) to give the corresponding sulfonamides with pendant oligo(ethyleneimines). The resulting modified resins are useful in the separation of aldehydes from hydrocarbon mixtures. Sorption of aldehydes occurs through formation of both Schiff base and five-membered (imidazoline) rings. Sorbed aldehydes can readily be stripped from the resins by treating with dilute acid solutions. Since the sulfamide bond has a reasonable stability toward acid-base hydrolysis, the loaded resins can be regenerated and recycled by simple acid-base washings, without losing their activity. In the present study, sorption and desorption kinetics of acetaldehyde, benzaldehyde, and salicylaldehyde have been investigated under different conditions. The aldehyde sorption obeys second-order kinetics. The method presented is applicable for all aromatic aldehydes. However, in the case of aliphatic aldehydes carrying an α-hydrogen, aldol condensation products form in solution. So aliphatic aldehydes and their aldol products are sorbed together by the resins. This limits the recovery of aliphatic aldehydes. Consequently, the resins described are cost effective sorbents for the removal and recovery of aromatic aldehydes from various mixtures. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 2857-2864, 1997
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    Journal of Polymer Science Part A: Polymer Chemistry 35 (1997), S. 2539-2548 
    ISSN: 0887-624X
    Keywords: nonaqueous ; dispersion polymerization ; functional submicron particles ; poly(methyl methacrylate) ; SEP stabilizer ; oxazoline ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A novel oxazoline-functional methacrylate was prepared and employed as comonomer to produce nonaqueous dispersions of oxazoline-functional polymer particles. In nonaqueous free radical dispersion copolymerization of methylmethacrylate in the presence of oxazoline-functional methacrylate, ethyleneglycoldimethacrylate crosslinking agent, AIBN initiator, and polystyrene-block-poly(ethene-alt-propene) dispersing agent, the average polymer particle size, varying between 100 and 500 nm, was controlled by the dispersing agent contents. According to titration with HClO4 all oxazoline groups regardless of their location at particle surface or bulk, were accessible. Glass transition temperature decreased from 120 to 0°C when oxazoline functional methacrylate was increased from 0 to 95 mol %. As imaged by atomic force microscopy incorporation of the new oxazoline-functional methacrylate improved film formation. Oxazoline-functional polymer particles were easy to redisperse in a variety of other diluents. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 2539-2548, 1997
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    Journal of Polymer Science Part A: Polymer Chemistry 35 (1997), S. 2561-2568 
    ISSN: 0887-624X
    Keywords: polymerizable surfactants ; surfmers ; alkyl sodium sulfopropyl maleate ; emulsion polymerization ; styrene ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The copolymerization of styrene with two polymerizable surfactants (surfmers) based on maleic acid (dodecyl sodium sulfopropyl maleate and tetradecyl sodium sulfopropyl maleate) was studied in batch emulsion polymerizations. The surfmer conversion was obtained by serum replacement with water and subsequent analysis of the recovered, unreacted surfmers with two-phase titration. It was found that both surfmers copolymerized well with styrene and their partial conversion was higher than that of styrene. These results are contradictory to what was found before in the literature using ultrafiltration with methanol, and the differences are explained on the basis of oligomer formation: The oligomers formed are detected if the latices are washed with methanol. It was found that at the end of the polymerization (almost complete conversion of both styrene and surfmer) only 45% of the surfmer groups were present on the particle surface, which is in agreement with a high conversion of the surfmer at the beginning of the reaction. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 2561-2568, 1997
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  • 60
    ISSN: 0887-624X
    Keywords: glass transition temperature ; acrylate ; methacrylate ; prediction ; energy density function ; EVM model ; QSPR ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: We describe an original QSPR model called the EVM model (Energy, Volume, Mass) to calculate the glass transition temperature (Tg) of aliphatic acrylate and methacrylate homopolymers using classical molecular mechanics and dynamics. The latter was used to calculate an energy density function related to the cylindrical volume of a 20 monomer unit polymer segment (TSSV, Total Space around a Standard deviation Volume). We then calculated the Tg as a function of this density function and the repeat unit molecular weight, although no interchain interactions were taken into account. For linear and branched aliphatic acrylate and methacrylate polymers, the standard deviation from linear regression was 12 K, and the r2 was 0.96. The model allows calculation of the Tg with an average absolute error of error of 10% for linear and branched derivatives not included in the original linear regression analysis. The results obtained with the EVM model are compared with those obtained with Bicerano's model. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 2579-2590, 1997
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    Journal of Polymer Science Part A: Polymer Chemistry 35 (1997), S. 2591-2597 
    ISSN: 0887-624X
    Keywords: Gd(OCOCCl3)3 catalyst ; copolymerization of styrene and methyl methacrylate ; monomer reactivity ratio ; HOMO and LUMO levels ; e value of monomers ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The polymerization of polar monomers such as methyl methacrylate (MMA), methyl acrylate (MA), methacrylonitrile (MAN), and acrylonitrile (AN) was carried out with gadolinium-based Ziegler-Natta catalysts [Gd(OCOCCl3)3-(i-Bu)3Al-Et2AlCl] in hexane at 50°C under N2 to elucidate the effect of the monomer's HOMO(highest occupied moleculor orbital) and LUMO (lowest unoccupied molecular orbital) levels on the polymerizability. In the case of homopolymerization, all monomers were found to polymerize and the order of relative polymerizability was as follows: MM 〉 MA 〉 MAN 〉 AN. On the other hand, the result of copolymerization of St with MMA shows that the values of the monomer reactivity ratios are r1 = 0.06 and r2 = 1.98 for St(M1)/MMA(M2). The monomer reactivity ratios of styrene (St), p-methoxystyrene (PMOS), p-methylstyrene (PMS), and p-chlorostyrene (PCS) evaluated as r1 = 0.55 and r2 = 1.07 for St(M1)/PMOS(M2), r1 = 0.38 and r2 = 0.51 for St(M1)/PMS(M2), and r1 = 0.72 and r2 = 1.25 for St(M1)/PCS(M2) were compared with those for St(M1)/MMA(M2). The copolymerization behavior is apparently different from the titanium-based Ziegler - Natta catalyst, regarding a larger monomer reactivity ratio of PCS. The lower LUMO level of PCS and MMA may enhance a back-donation process from the metal catalyst, therefore resulting in high polymerizability. These results are discussed on the basis of the energy level of the gadolinium catalyst and the HOMO and LUMO levels of the monomers. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 2591-2597, 1997
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    Journal of Polymer Science Part A: Polymer Chemistry 35 (1997), S. 2961-2968 
    ISSN: 0887-624X
    Keywords: polysulfane ; sulfur ; cyclic (arylene disulfide) ; copolymerization ; free radical ; rubber ; ring-opening polymerization ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Copolymerization reactions between cyclic(arylene disulfide) oligomers were studied. The cyclic disulfide oligomers derived from 4,4′-isopropylidene bisbenzenethiol gave soluble polysulfanes via copolymerization with S8. The copolymerization reactions were studied both in solution and melt by GPC and NMR. Solution copolymerization reactions can only form polysulfanes with up to three to four sulfur linkages; however, melt copolymerization reactions gave polysulfanes with up to seven sulfur linkages (average). The melt copolymerization reactions between cyclic disulfide oligomers derived from 4,4′-thiobis(benzenethiol) and S8 were studied using DSC, TGA, and DMTA. With increasing contents of sulfur in the polysulfanes, Tgs, 5% weight losses by TGA, and tan δ decreased. With seven sulfur linkages in the polymer, it is a rubber with a Tg of 12°C, a 5% weight loss by TGA of 249°C, and tan δ of 44°C, respectively. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 2961-2968, 1997
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    Journal of Polymer Science Part A: Polymer Chemistry 35 (1997), S. 1901-1907 
    ISSN: 0887-624X
    Keywords: biodegradable polymers ; serine ; glycolic acid ; 3-(O-benzyl)-L -serinylmorpholine-2,5-dione ; lactide ; ε-caprolactone ; ring-opening polymerization ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Serine/glycolic acid-based biodegradable polymers have been prepared by ring-opening homopolymerization of 3-(O-benzyl)-L-serinylmorpholine-2,5-dione, and ring-opening copolymerization of the morpholine-2,5-dione derivative and L-lactide/ε-caprolactone. The homopolymerization was carried out in the melt at 165°C for 3 min using stannous octanoate as the initiator and continued at lower reaction temperatures (130-150°C) for 48 h, using a molar ratio of monomer and initiator of 1000 yielded a polymer of Mn = 4000. The polymer prepared by homopolymerization of the morpholine-2,5-dione derivative was composed of alternating protected serine and glycolic acid residues. Random copolymers of serine and glycolic acid and L-lactic acid/ε-caprolactone were synthesized by copolymerization reaction of 3-(O-benzyl)-L-serinylmorpholine-2,5-dione and lactide or ε-caprolactone in the melt at 165°C for 3 min and further reaction at 130°C using stannous octanoate as an initiator. The polymers were deprotected and functionalized through the side chain hydroxyl group of serine residues with an acrylate moiety for applications in injectable drug delivery, cell encapsulation. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 1901-1907, 1997
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    Journal of Polymer Science Part A: Polymer Chemistry 35 (1997), S. 2487-2492 
    ISSN: 0887-624X
    Keywords: radical ; polyaddition ; spiroacetal ; bifunctional vinylcyclopropane ; dithiol ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Radical polyadditions of vinylcyclopropane having spiroacetal moiety, 1,10-divinyl-4,8,12,15-tetraoxatrispiro[2.2.2.2.2.2] pentadecane (1), and various dithiols were examined. 1 was prepared by the reaction of 1,1-dichloro-2-vinylcyclopropane and pentaerythritol, and radical polyadditions of 1 and dithiols were carried out at 60 and 120°C for 20 h in the presence of an appropriate initiator (3 mol % vs. 1) in degassed sealed ampoules or at 20°C under photo irradiation by using a 400 W high-pressure mercury lamp. Poly(1), pale yellow transparent viscous polymers was isolated by reprecipitation with ether containing a small amount of triethylamine to avoid hydrolysis of the polymer. The obtained polymers were soluble in chlorobenzene, DMF, and chloroform but insoluble in ether and n-hexane. The molecular weights of the polymers obtained from aliphatic dithiols were smaller than those from aromatic ones. The structure of the polymer was determined by comparing the NMR spectra with those of the model compounds, which were obtained by radical addition of 1 and benzyl mercaptan. The reaction proceeded through radical polyaddition of dithiol to 1 via radical ring-opening polymerization of the cyclopropane ring. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 2487-2492, 1997
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    Journal of Polymer Science Part A: Polymer Chemistry 35 (1997), S. 2479-2486 
    ISSN: 0887-624X
    Keywords: polyoxymethylene ; trioxane ; ethylene oxide ; acetal copolymer ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Recently, we have observed the following phenomena during the copolymerization of trioxane and ethylene oxide using a boron trifluoride initiator. In almost all of the polymerization cases, all polymers were soluble in a p-chlorophenol-tetrachloroethane mixed solvent at 90°C. However, in some polymerization cases, a small portion of the polymer was insoluble at this temperature, and this mixed solvent-insoluble fraction showed a higher melting point than that of the other fractions. Scanning electron microscope (SEM) photographs of the polymer showed that a highly fibrous structure was formed for the mixed solvent-insoluble fraction, and this highly packed structure is thought to be the origin of the high melting fraction. The nature of this high melting fraction was further examined using X-ray diffraction and Raman spectra. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 2479-2486, 1997
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    Journal of Polymer Science Part A: Polymer Chemistry 35 (1997), S. 2521-2532 
    ISSN: 0887-624X
    Keywords: allyl ethers ; 1-propenyl ether monomers ; cationic polymerization ; isomerization-polymerization of allyl ethers ; Group VIII carbonyls ; organosilanes ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Alkyl allyl ethers undergo facile thermally induced isomerization to alkyl 1-propenyl ethers in the presence of Group VIII transition metal carbonyl compounds as catalysts. The addition of a silane containing a Si—H bond to these systems results in a catalyst system that is capable of not only isomerizing the allyl ether to the 1-propenyl ether, but further results in the polymerization of these later compounds. High molecular weight polymers can be obtained directly from the alkyl allyl ether in a single step. The scope and limitations of these polymerizations are described. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 2521-2532, 1997
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    Journal of Polymer Science Part A: Polymer Chemistry 35 (1997), S. 2533-2534 
    ISSN: 0887-624X
    Keywords: N-vinylformamide ; intrinsic viscosity ; Mark-Houwink ; constants ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: No abstract.
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    Journal of Polymer Science Part A: Polymer Chemistry 35 (1997), S. 2535-2537 
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: No abstract.
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    Journal of Polymer Science Part A: Polymer Chemistry 35 (1997), S. 2549-2560 
    ISSN: 0887-624X
    Keywords: halfsandwich metallocene ; homogeneous catalysis ; terpolymerization ; ethene ; styrene ; 1-octene ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Ethene was co- and terpolymerized with 1-octene and styrene using the methylalumoxane (MAO) activated halfsandwich metallocene Me2Si(Me4Cp)(N-t.-butyl)TiCl2(Cp = cyclopentadienyl, Me = methyl) as catalyst. At temperatures of 40 and 60°C styrene concentration was varied in order to investigate the influence of the comonomers. Despite decreasing the overall activity with respect to ethene/1-octene copolymerization, polymerization activity was found to exibit a relative maximum with increasing styrene concentration. An explanation is given taking two different comonomer effects into account. Low styrene concentration promoted higher 1-octene incorporation compared to ethene/1-octene copolymerization but significantly lowered the molecular weight of the terpolymers. With constant ethene and 1-octene concentration it was possible to produce ethene/1-octene/styrene terpolymers with styrene content varying from 0 to 25 mol % and 1-octene content varying from 8 to 21 mol %. All terpolymers were amorphous. With constant ethene content it was found possible to vary their glass transition temperature with 1-octene/styrene molar ratio incorporated in the terpolymer. 13C-NMR spectroscopic microstructure analysis showed that no styrene/1-octene sequences were found in the terpolymer backbone. Furthermore terpolymerizations were conducted successfully incorporating norbornene, 1,5-hexadiene and propene as monomers in terpolymertization with ethene and styrene. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 2549-2560, 1997
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  • 70
    ISSN: 0887-624X
    Keywords: mesogenic pyridinium salts ; poly(4-vinylpyridinium) salts ; ionic liquid crystalline structure ; liquid crystalline molecules ; liquid crystalline polymers ; smectic organization ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: In order to demonstrate the important smectic power of the ionic functions present in mesogenic molecules, a series of N-alkylpyridinium bromides ω-substituted with (4-cyanobiphenylyl)oxy or [4-(2-methyl-1-butoxy)biphenylyl]oxy mesogenic group and their analogous 4-vinylpyridinium polymers were synthesized and characterized. The liquid crystalline behavior was studied by differential scanning calorimetry, polarizing optical microscopy, and X-ray diffraction. Smectic mesophases, namely A, B, and E, were identified for the low molecular weight compounds, whereas smectic A and E mesophases were identified for the analogous polymers. Both structures were found to be very similar. They consist of single layers of upright molecules laterally arranged head-to-tail; the polymer backbone is inserted in between the layers. The monolayer smectic ordering observed in spite of the presence of the interacting cyano and chiral groups demonstrates the prevailing effect of the electrical interactions upon the structural organization. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 2569-2577, 1997
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    Journal of Polymer Science Part A: Polymer Chemistry 35 (1997), S. 2599-2605 
    ISSN: 0887-624X
    Keywords: polyoctenamer ; singlet oxygen ; photo-oxidation ; grafting ; polymeric hindered amine stabilizers ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Polyoctenamer reacts with singlet oxygen to produce polymeric pendant hydroperoxide groups. Anthracene was used as a sensitizer for production of singlet oxygen under 365 nm irradiation. Remarkable differences were observed when the reaction was performed in the solid state or in the solution. Hydroperoxidation in the solution was much slower than in the film, and only pendant hydroperoxides were produced. Conversely, two processes take place in the film. One is the “ene” reaction of singlet oxygen with double bonds producing hydroperoxides as in the solution; the second one is a radical process producing both carbonyl products and additional hydroperoxides. This process went on after anthracene was completly consumed. Irradiation (λ 〉 300 nm) of hydroperoxidized polyoctenamer solution in the presence of monomers (2,2,6,6-tetramethyl or 1,2,2,6,6-pentamethyl-4-piperidyl acrylate) or stable nitroxyl radicals (stearoyloxy-2,2,6,6-tetramethyl-4-piperidyl-N-oxyl or TEMPO) grafted these monomers or stable radicals onto the polyoctenamer. Light stabilizing efficiency of grafted and low molecular additives was tested in polyoctenamer. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 2599-2605, 1997
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    Journal of Polymer Science Part A: Polymer Chemistry 35 (1997), S. 2607-2617 
    ISSN: 0887-624X
    Keywords: poly(dimethylsiloxane) ; emulsion graft copolymerization ; hydrogen abstraction reaction ; peroxide ; NMR ; lubricity ; MOPAC ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The influence of radical initiators upon the emulsion graft copolymerization of styrene and acrylonitrile onto poly(dimethylsiloxane) (PDMS) was studied. As initiators, a series of peroxides and hydroperoxides were coupled with ferrous sulfate, among which the tert-butyl peroxylaurate system gave the highest grafting efficiency (30%). The tert-butyl peroxylaurate initiator fulfills the criteria for efficient radical grafting by generating only the tert-butoxy radical, which is reluctant to form a carbon radical via β-scission, being highly hydrophobic, and not carrying a tertiary hydrogen that may be abstracted by a radical. 13C-NMR analysis of the products showed that the grafting occurred on the silylmethyl groups of PDMS to give 10-25 grafts per polymer and graft ratio in the range 44-140%. The PDMS graft copolymers thus obtained could be used as surface-modifying agents to improve the lubricity and water-repellency of ABS [poly(styrene-co-acrylonitrile)-graft-polybutadiene]. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 2607-2617, 1997
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    Journal of Polymer Science Part A: Polymer Chemistry 35 (1997), S. 2631-2643 
    ISSN: 0887-624X
    Keywords: macroporous beads ; poly(chloromethylstyrene) ; chiral separation ; HPLC ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Reactive monodisperse porous poly(chloromethylstyrene-co-styrene-co-divinylbenzene) beads have been prepared by a staged templated suspension polymerization method with different concentrations of linear polystyrene porogen and chloromethylstyrene in the polymerization mixture. The presence of a small amount of linear polystyrene in the polymerization mixture leads to a dramatic increase in both the pore size and the pore volume of the resulting beads. In contrast, addition of chloromethylstyrene leads to lower surface areas and smoother surfaces due to the reduced compatibility between the polystyrene porogen and the newly formed crosslinked chains. The modification of chloromethylstyrene beads by Gabriel synthesis to obtain aminated beads has also been studied. The final number of primary amino groups is related to the starting concentration of functional benzyl chloride moieties rather than to the porous properties. Both π-basic and π-acidic type chiral selectors, (R)-1-(1-naphthyl)-ethylamine and (R)-N-(3,5-dinitrobenzoyl)phenylglycine, respectively, have been attached to the amino functionalized beads, and the resulting chiral beads have been used in the model HPLC separations of enantiomers. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 2631-2643 1997
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    Journal of Polymer Science Part A: Polymer Chemistry 35 (1997), S. 2955-2960 
    ISSN: 0887-624X
    Keywords: radical polymerization ; end groups ; methyl methacrylate ; styrene ; benzoyl peroxide ; benzoyloxy radical ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: There has been a suggestion that, for polymerizations initiated by benzoyl peroxide, the use of benzene as diluent may cause uncertainties about the conclusions reached from studies of the end groups in the resulting polymers. It is now shown that no substantial changes are caused by the replacement of benzene by other solvents. This finding contributes to the conclusion that any capture of benzoyloxy radicals by benzene is only transitory and does not invalidate the deductions made from the results of analyses of polymers for benzoate and phenyl end groups derived from the peroxide. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 2955-2960, 1997
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  • 75
    ISSN: 0887-624X
    Keywords: phenyl ethynyl ether imides ; amorphous or semicrystalline morphology ; volatile free thermosetting matrix ; structural adhesives ; composites ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Fully cyclized, organo soluble, phenylethynyl-terminated, ether-imide oligomers of 2-10,000 g/mol (Mn) were prepared by the reaction of 2,2′-bis[4-(3,4-dicarboxyphenoxy)phenyl]-propane dianhydride (bisphenol-A dianhydride, BPADA) with a stoichiometric excess of either para, meta, or isomeric mixtures of phenylene diamine and phenylethynylphthalic anhydride (4-PEPA) endcapper. High para-containing oligomers produced semicrystalline powders, but the all meta isomer was completely amorphous. The lower molecular weight oligomers displayed an attractive low viscosity melt and were cured to very high gel content networks at 350-380°C for 30-90 min. The cured 3000 g/mol oligomers showed a (DSC) glass transition temperature (Tg) of 267°C and produced tough, solvent-resistant films. Excellent adhesion to surface-treated titanium alloys was achieved, as judged by single-lap shear measurements. Resin infusion molding was conducted, which permitted low-void, graphite-fabric composite panels to be prepared. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 2943-2954, 1997
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  • 76
    ISSN: 0887-624X
    Keywords: solution imidization ; kinetics ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: In this work, thermal solution imidization kinetics of two high performance polyimides, prepared from the polycondensation of pyromellitic dianhydride (PMDA) and 3,3′,4,4′-benzophenonetetracarboxylic dianhydride (BTDA) with 4,4′-bis(3-aminophenoxy)diphenylsulfone (DAPDS) were investigated using nonaqueous titration technique with tetramethylammonium hydroxide. Most of the kinetic investigations, found in the literature, are based on the aromatic p-diamines.1,2 In the present work, attention was focused on imidization kinetics with m-substituted aromatic diamines having electron donating (—O—) and electron withdrawing (—SO2—) groups in the same molecule. Kinetic parameters, namely the rate constants, activation energies, entropies and enthalpies of imidization reactions were determined and compared with the literature values. It is reported in literature3 that electron affinities of dianhydrides and ionization potentials of diamines, have strong influence on the reaction rate and activation energies of imidization. Activation energy (Ea) values were found to be 66 and 57 kJ/mol for DAPDS/PMDA and DAPDS/BTDA respectively, and order of reaction was found to be second order. Polyimides DAPDS/PMDA and DAPDS/BTDA, subjected to kinetic investigation, showed glass transition temperatures of 267°C and 241°C, both were found to be thermally stable up to 500°C. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 2981-2990, 1997
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    Journal of Polymer Science Part A: Polymer Chemistry 35 (1997), S. 2999-3008 
    ISSN: 0887-624X
    Keywords: 7,7′-coumarinyl polymethylene dicarboxylate ; photopolymerization ; fluorescence ; coumarin ; dimerization ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: All eight 7,7′-(4-methylcoumarinyl) polymethylene dicarboxylates (3, 4) containing terminal photoreactive coumarin chromophores show strong fluorescence intensities at room temperature in dimethyl sulfoxide (DMSO) and CH2Cl2. After irradiation with 350 nm light for 2 h, the fluorescence characteristics of the dicarboxylates reveal their photopolymerization paths. On irradiation of the unsubstituted dicarboxylates (3) in DMSO, singlet excited state excimers are formed, leading to syn head-to-head coumarin dimer configuration. However, for all dicarboxylates in CH2Cl2, the dimerization of the coumarin chromophore proceeds via a triplet excited state in the presence of benzophenone to form the anti-configuration photoproducts. Further confirmations of the reaction mechanism are made by kinetic studies. At high concentration, photopolymerization of 7,7′-(4-methylcoumarinyl) polymethylene dicarboxylate (4c) obeys zero-order and first-order kinetics for coumarin chromophore and benzophenone, respectively. This is a powerful proof of the proposed mechanism of a triplet excited state reaction. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 2999-3008, 1997
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    Journal of Polymer Science Part A: Polymer Chemistry 35 (1997), S. 3017-3025 
    ISSN: 0887-624X
    Keywords: polyesters ; photodegradation ; thermal degradation ; triazene chromophore ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The synthesis of photosensitive polymers that contain the triazeno group (Ph—N=N—NR2) as a sensitive unit in their backbone is reported. The synthesis pathway consists of difunctional alcohols incorporating the photosensitive unit that react with diacyl derivatives to give the respective polyesters. Upon irradiation, the photosensitive chromophores both in monomeric and polymeric surroundings are cleaved fast and irreversibly, as shown in photolytic studies and their kinetic evaluations. Thermogravimetrical investigations indicate the loss of nitrogen being the initial thermal decomposition step and exhibit stabilities sufficient for the requirements in applications as photoresists. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 3017-3025, 1997
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    Journal of Polymer Science Part A: Polymer Chemistry 35 (1997), S. 3075-3077 
    ISSN: 0887-624X
    Keywords: N-isopropylacrylamide ; radiation-induced polymerization ; crosslinking ; degradation ; thermo-responsive gel ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
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  • 80
    ISSN: 0887-624X
    Keywords: ring-opening metathesis polymerization ; Diels-Alder synthesis ; cycloaddition ; reaction injection molding ; crosslinking ; rubber-modified polymers ; morphology ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: 5-(3-Cyclohexen-1-yl)-2-norbornene [CHNB] has been shown to form a very lightly crosslinked polymer (Tg = 127°C) with good elongation via ring-opening metathesis polymerization (ROMP). Based on swelling behavior with added norbornadiene dimer, the low crosslink density is ascribed to 〈0.5% participation by the cyclohexenyl ring. Compared to dicyclopentadiene (DCPD), CHNB polymerizations were less exothermic, required less catalyst, and exhibited greater molding latitude, which are advantageous for Reaction Injection Molding (RIM). Styrene-isoprene and styrene-ethylene/butylene block copolymers were effective impact modifiers for polyCHNB, forming large particle morphologies. Small rubber particles formed from styrene-butadiene block copolymers were not effective for impact enhancement of polyCHNB, in contrast to polyDCPD. Rubber-modified polyCHNB retained impact resistance four to six times longer than polyDCPD samples when aged in air at 50-70°C. Related RIM-ROMP of liquid monomer mixtures prepared by cyclopentadiene cycloadditions with 4-vinyl-1-cyclohexene, cis-1,3-divinylcyclopentane, 3,5-divinylcyclopentene or cis-2,4-divinylbicyclo[3.3.0]oct-6-ene formed highly crosslinked, less ductile copolymers with Tgs as high as 206°C. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 3049-3063, 1997
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    Journal of Polymer Science Part A: Polymer Chemistry 35 (1997), S. 3083-3086 
    ISSN: 0887-624X
    Keywords: vinylidene ; scission ; polypropylene ; controlled-rheology ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
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    Journal of Polymer Science Part A: Polymer Chemistry 35 (1997), S. 3079-3082 
    ISSN: 0887-624X
    Keywords: polysilane ; copolymer ; cyclopentamethylene side chain ; trifluoropropyl side chain ; IR absorption ; UV absorption ; fluorescence ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
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    Journal of Polymer Science Part A: Polymer Chemistry 35 (1997), S. 3095-3100 
    ISSN: 0887-624X
    Keywords: p-nitracetanilide ; photoinitiator ; free radical ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The polymerization rate of methyl methacrylate photosensitized by p-nitroacetanilide in the presence of triethylamine was measured as a function of the amine and monomer concentrations. The polymerization proceeds readily in high-polarity media (acetonitrile/monomer) but is negligible in nonpolar media. The polymerization rate increases with the amine concentration up to 0.15M. Further increase in amine concentration does not change the polymerization rate. A similar behavior was observed for the photobleaching of the nitro compound. ESR studies show the formation of a nitro and an amine free radical, the latter free radical being the active species that adds to the monomer. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 3095-3100, 1997
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    Journal of Polymer Science Part A: Polymer Chemistry 35 (1997), S. 3087-3094 
    ISSN: 0887-624X
    Keywords: N-vinylisobutyramide ; N-vinylalkylamide ; water-soluble polymers ; thermosensitive property ; polyN-isopropylacrylamide ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: N-vinyl-n-butyramide (NVBA), N-vinylisovaleramide (NVIVA), and N-vinyl-n-valeramide (NVVA), which are N-vinylalkylamides with different alkyl groups were synthesized and their solution behavior in a polymeric form was examined. Copolymers of N-vinylisobutyramide (NVIBA) with N-vinylacetamide (NVA), NVIBA with NVVA, and NVVA with NVA were prepared by the solution polymerization to control the LCSTs. The resultant polyNVBA showed a lower critical solution temperature (LCST) sharply at 32°C, but polyN-vinylisovaleramide (polyNVIVA) and polyN-vinyl-n-valeramide(polyNVVA) that have n-butyl and isobutyl groups, respectively, on their side chains were insoluble even in cold water. The water solubility of the resulting polymers was found to vary, depending on the molecular shapes as well as the side chain length of the alkyl groups in question. The copolymers consisting of NVVA, NVIBA, and NVA in water showed LCSTs sharply between 10 and 90°C, depending on changes in their comonomer content. It was found that the changes in LCST that are caused by the incorporation of comonomers are due to changes in the overall hydrophilicity of the polymer. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 3087-3094, 1997
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    Journal of Polymer Science Part A: Polymer Chemistry 35 (1997), S. 3101-3115 
    ISSN: 0887-624X
    Keywords: molten state reactivity cyanate esters ; epoxy resins ; NMR ; 13C (liquid and solid) ; FTIR ; DSC ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Based on an FT-IR and 13C-NMR spectroscopic study using model compounds, we previously proposed an epoxy-cyanate coreaction path in the molten state, by identifying all chemical species and their role in the reaction mixture. These data were then applied to difunctional systems involving diglycidyl ether of bisphenol A (DGEBA) and bisphenol A dicyanate (BADCy), with mixtures prepared in different epoxy/cyanate ratios. Using FT-IR and solid state 13C-NMR spectroscopic analyses, we show the effect of epoxy group concentration on the final structure of the system. We were able to show that epoxy functions react on the triazine rings formed in the first step of homopolymerization of cyanates, and that the structure of the final system depends on their initial concentration. In addition, a study of difunctional systems for identical cyanate-epoxy stoichiometry was undertaken in the presence of anionic (imidazole) and metallic (AcAcCu and AcAcCr) catalysts in order to determine their effect on the reactivity of the two monomers and on the structure of the final system. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 3101-3115, 1997
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    Keywords: cardanol ; polyurethane ; semi-interpenetrating polymer networks ; SEM ; XRD ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Substituted aromatic compounds incorporated-cardanol-formaldehyde novolac resins were synthesized by acid base catalyzed reactions. A number of improved high temperature stable interpenetrating polymer networks (semi-IPNs) were prepared by condensing novolac resins and polyurethanes prepared from castor oil and diisocyanates of varying NCO/OH ratio. The structure of these semi-IPNs were studied using various characterization techniques such as IR, nuclear magnetic resonance (NMR) spectra. The scanning electron microscopy of some of the semi-IPNs have been studied and the morphology has been examined. The samples were subjected to wide angle X-ray diffraction analysis. The degree of crystallinity (Xcr) was computed on the basis of the crystal defect concept, developed by Ruland and Vonk. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 3117-3124, 1997
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    Journal of Polymer Science Part A: Polymer Chemistry 35 (1997), S. 3131-3139 
    ISSN: 0887-624X
    Keywords: methacryloyl-terminated poly(oxyethylene) ; PEO-MA ; p-vinylbenzyl-terminated polyoxyethylene ; PEO-St ; PEO macromonomers ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The kinetics of dispersion copolymerization of methacryloyl-terminated poly(oxyethylene) (PEO-MA) and p-vinylbenzyl-terminated (PEO-St) polyoxyethylene macromonomers and styrene (St), initiated by a water- and/or oil-soluble initiator, was investigated using conventional gravimetric and NMR methods at 60°C. The batch copolymerizations in the water/ethanol continuous phase were conducted to high conversion. The rate of polymerization was described by the curve with a maximum at very low conversion. The initial rate of polymerization and the number-average molecular weight were found to decrease with increasing [PEO-MA], and the decrease was more pronounced in the range of a high macromonomer concentration. The rate per particle (at ca. 20% conversion) was found to be proportional to the -1.55th, the particle size to the -0.92nd, and the number of particles (at final conversion) to the 3.2nd power of [PEO-MA], respectively. At the beginning of polymerization the continuous phase is the main reaction locus. As the polymerization advances, the reaction locus is shifted from the continuous phase to the polymer particles. The transform of the reaction loci from the continuous phase to the polymer particles increases the rate of polymerization and the polymer molecular weights. The increase of the weight ratio PEO-MA/St favors the formation of monodisperse polymer particles, the colloidal stability of dispersion, and the formation of a larger number of polymer particles. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 3131-3139, 1997
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    Journal of Polymer Science Part A: Polymer Chemistry 35 (1997), S. 3125-3130 
    ISSN: 0887-624X
    Keywords: polyacrylate ; isomerization ; isoimides ; imides ; amic acid ; ethyl chloroformate ; acryloyl chloride ; AIBN ; dicyclohexylcarbodiimide ; phthalic anhydride ; aminophenols ; thermosetting plastic ; free radical polymerization ; florisil ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Several isoimides substituted with hydroxylated substituents were prepared, and allowed to react with acryloyl chloride to form the corresponding acrylate esters. The acrylates were polymerized free radically using AIBN as the initiator yielding medium molecular weight polyacrylates. Upon warming the prepared polyacrylates or treatment with base most of the isoimide pending groups rearranged to the stable form of the corresponding imides. These rearrangements were accompanied by increase in softening points of the polymers forming thermally more stable resins. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 3125-3130, 1997
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    Journal of Polymer Science Part A: Polymer Chemistry 35 (1997), S. 3151-3160 
    ISSN: 0887-624X
    Keywords: nanocatalysts ; colloids ; polyelectrolytes ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Several palladium and platinum nanocatalysts protected by cationic polyelectrolytes were prepared by the in-situ reduction of palladium chloride, PdCl2, and dihydrogen hexachloroplatinate, H2PtCl6. The particle sizes and size distributions were determined by transmission electron microscopy, and the colloids were further characterized by UV-vis spectroscopy. The catalytic activity of these nanoparticles was qualitatively investigated by the hydrogenation and conversion of cyclohexene as a model reaction and compared to palladium and platinum colloids protected by a selection of water-soluble, nonionic polymers. The results show that the catalytic activity is strongly influenced by the protective polymer chosen, as well as particle size and morphology. The use of cationic polyelectrolytes decreases the catalytic activities significantly, in comparison to several water-soluble, nonionic polymers investigated. The effects depend strongly on the particular metal, as illustrated in this case by differences observed between palladium and platinum. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 3151-3160, 1997
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    Journal of Polymer Science Part A: Polymer Chemistry 35 (1997), S. 3141-3149 
    ISSN: 0887-624X
    Keywords: emulsion polymerization ; persulfate cations ; redox initiation systems ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The emulsion polymerization of vinyl acetate (VAc) was carried out by using redox initiation systems of different persulfate cations such as potassium persulfate (PPS), sodium persulfate (SPS), and ammonium persulfate (APS); each of them was coupled with developed acetone sodium bisulfite adduct (AcSBS) as a reducing agent. The rate of polymerization was found to be dependent on the initiator concentration to the powers 1.04, 1.02, and 0.34, respectively. The effect of the different cations of the oxidizing agents upon the stability of the prepared emulsion lattices was studied by using the sedimentation method. The effect of the different cations on the morphological characteristics of some of the produced lattices was also studied. Finally, the activation energies of these reactions for potassium, sodium, and ammonium persulfate were found to be 0.84 × 104, 1.92 × 104, and 6.68 × 104 J/mol, respectively. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 3141-3149, 1997
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    Journal of Polymer Science Part A: Polymer Chemistry 35 (1997), S. 3169-3179 
    ISSN: 0887-624X
    Keywords: unsaturated polyester resin ; poly(ethylene oxide) ; hydrogen-bonding interaction ; polymer blend ; polymer morphology ; crystallization kinetics ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Hydrogen-bonding interaction between the two components of the poly(ethylene oxide) (PEO)/oligoester (OER) blends and the PEO/crosslinked unsaturated polyester resin (PER) blends was found to be an important driving force to the miscibility of these polymer blends. Its strength is approximately as strong as the self-association of hydroxyl groups in either the pure OER or the pure PER. The crystallization kinetics and morphology of PEO in PEO/PER blends was remarkably affected by crosslinking. It was found that the overall crystallization rate of PEO in PEO/PER blends is larger than that in PEO/OER blends at the crystallization temperature investigated, which was considered to be the result of nucleation controlling mechanism. With decreasing PEO content, the regular shape of PEO spherulites turns irregular in PEO/OER blends, whereas in PEO/PER blends, the birefrigent spherulites turns into dendritic structures. Raising the crystallization temperature favors the formation of dendritic textures in PEO/PER blends. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 3169-3179, 1997
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    Journal of Polymer Science Part A: Polymer Chemistry 35 (1997), S. 3227-3234 
    ISSN: 0887-624X
    Keywords: phenolphthalein-N-(methylanilide) ; spectral analysis ; terephthaloyl chloride, cardo polyesters ; thermal properties ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: New phthalide-containing bisphenols, phenolphthalein-N-(3-methylanilide) (3-PMA), and phenolphthalein-N-(4-methylanilide) (4-PMA), were synthesized from phenolphthalein and m- and p-toluidines. These bisphenols were polycondensed with terephthaloyl chloride (TPC) using an interfacial or solution polymerization technique to yield new polyesters. Copolymers were also obtained by utilizing different molar proportion of phenolphthalein (PPH) and 3-PMA or 4-PMA with TPC. The polymers prepared by solution polymerization were obtained in 93-99% yields and showed reduced viscosities in the range 0.37-0.83 dL/g. They were readily soluble in chlorinated hydrocarbons and aprotic polar solvents. The polyesters showed glass transition temperatures in the range 261-300°C as measured by DSC. Thermogravimetric analysis of the polyesters indicated no weight loss below 408°C under N2 atmosphere. Structure-property correlations among these cardo polyesters have been discussed. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 3227-3234, 1997
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    Journal of Polymer Science Part A: Polymer Chemistry 35 (1997), S. 3235-3240 
    ISSN: 0887-624X
    Keywords: seven-membered cyclic sulfite ; six-membered cyclic sulfile ; cationic equilibrium polymerization ; depolymerization ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Cationic polymerization of a seven-membered cyclic sulfite (7CS) was carried out with methyl trifluoromethanesulfonate as a catalyst in chlorobenzene. The final conversions of 7CS were 22, 41, 52, and 60% in the polymerizations at 25°C with the initial monomer concentrations of 3, 4, 5, and 6M, respectively. The calculated monomer concentration at equilibrium was evaluated as 2.4M in any case. The conversion of 7CS decreased as the polymerization temperature rose. These results support the fact that this polymerization is an equilibrium one. ΔH0 and ΔS0 in the polymerization were evaliuated as -0.765 kcal/mol and -4.18 cal/mol by Dainton's equation, respectively. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 3235-3240, 1997
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    Journal of Polymer Science Part A: Polymer Chemistry 35 (1997), S. 3249-3254 
    ISSN: 0887-624X
    Keywords: unsymmetric Schiff base monomer ; linear polymeric Schiff base complexes ; polymeric catalyst ; unfunctionalized olefins ; epoxidation ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A polymerizable unsymmetric tetradentate Schiff base with one vinyl group 3 was synthesized and copolymerized with styrene in toluene. Mn(III) ion was quantitatively incorporated into the copolymers by the functional moieties. The resulting linear polymer-bound manganese complexes (4a′ and 4b′) were used as catalyst under homogeneous condition for selective epoxidation of unfunctionalized olefins (i.e. styrene, α-methylstyrene and cyclohexene) at room temperature in the presence of iodosylbenzene (PhIO) as the terminal oxidant. The efficacy of epoxidation using the polymeric catalysts was comparable to that of the monomolecular analog. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 3249-3254, 1997
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    Journal of Polymer Science Part A: Polymer Chemistry 35 (1997), S. 3255-3262 
    ISSN: 0887-624X
    Keywords: telechelic oligomer ; emulsion polymerization ; latex ; ozonolysis ; constructive degradation ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Poly(methyl methacrylate-co-butadiene), Poly(butyl methacrylate-co-butadiene) and Poly(methyl methacrylate-co-2,3-dimethyl butadiene) latices (a.k.a. latexes) were prepared by monomer-starved emulsion polymerization. The polymerizations were followed by GPC. It was found that the molecular-weight distribution did not alter significantly with conversion if the polymerizations were carried out at a feed rate of 0.03 cm3 s-1 per 1000 cm3 of reaction medium and a temperature of 70°C. Slower rates of monomer addition led to broadening of the molecular-weight distribution. The resultant latices were swollen with varying amounts of toluene. Ozonolysis of the swollen and nonswollen latices yielded latices of polymer ozonides. Oxidation, with selenium oxide/hydrogen peroxide reagent, converted the ozonides to latices of carboxylic acid or methyl ketone ended telechelic oligomers. It was found that the molecular weights of the oligomers were a function of toluene concentration. Colloidal stability was found to be a function of end-group structure. Thus, carboxylic acid end groups impart extra stability to the colloid while methyl ketone end groups do not. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 3255-3262, 1997
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    Journal of Polymer Science Part A: Polymer Chemistry 35 (1997), S. 3263-3273 
    ISSN: 0887-624X
    Keywords: poly(ether urethane urea)/Lycra 146C ; chlorine ; oxidative degradation ; free radical mechanism ; phase separation/mixing ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The tensile properties of polyether-based polyurethane (PU) filaments decrease with increasing chlorine concentrations as well as with treatment times. Fourier transform infrared (FTIR) results show the formation of quinoid, azo, and aldehyde groups in the chlorine-treated PU, and increased hydrogen bonding between the C—O—C in the soft segment and the N—H in the hard segments. A breakdown mechanism involving chain cleavages along the ether linkages in the soft segments as well as at the urethane linkages of the hard-soft segment interfaces is proposed. Chlorine-treated PU showed increased solubility in tetrahydrofuran (THF). The molecular weight data of the THF-soluble portion of treated PU also support the proposed locations of chain scissions. The increased soft segment Tg and Tm with increasing chlorine concentrations are results of increased phase-mixing and hydrogen bonding. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 3263-3273, 1997
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    Journal of Polymer Science Part A: Polymer Chemistry 35 (1997), S. 3241-3248 
    ISSN: 0887-624X
    Keywords: poly(ester-amide)s ; bis(2-oxazoline)s polymerization ; bulk polymerization ; glass transition temperature ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The preparation of linear poly(ester-amide)s from monoanhydrides, bis(2-oxazoline)s (namely 2,2′-(1,4-phenylene)bis(2-oxazoline)) and a third comonomer is discussed. The polymerization reactions were carried out in bulk between 150 and 200°C. When the third monomer is a diol, poly(ester-ester-amide)s are obtained. Diols of different structure were used: α,ω-diols having up to 12 carbon atoms, ethylene glycol oligomers (two or three repeating units), cyclic diols, etc.; glutaric, 3,3-dimethylglutaric and maleic anhydrides were used as monoanhydrides. The polymers were studied from the point of view of thermal properties, finding a substantial agreement between the structure of the monomers and the glass transition temperature of the polymers. By using primary diamines as a third comonomer, the reaction does not lead to the formation of a polymeric product. The failure of the polymerization was attributed to a competitive reaction that prevents the polymerization. After the amine group has reacted with the anhydride, cyclization of the so-formed carboxyalkylamide occurs, giving an imide derivative, unable to react further. Therefore, only a mixture of low molecular weight compounds is obtained in this case. When the diamine is secondary, the imidization reaction is not possible, and linear poly(amide-ester-amide)s are obtained. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 3241-3248, 1997
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    Journal of Polymer Science Part A: Polymer Chemistry 35 (1997), S. 3287-3297 
    ISSN: 0887-624X
    Keywords: optical activity ; dianhydride ; polyimide ; 1,1′-bi-2-naphthol ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A series of new optically active aromatic polyimides containing axially dissymmetric 1,1′-binaphthalene-2,2-diyl units were prepared from optically pure (R)-(+)- or(S)-(-)-2,2′-bis(3,4-dicarboxyphenoxy)-1,1′-binaphthalene dianhydrides and various aromatic diamines via a conventional two-step procedure that included ring-opening polycondensation and chemical cyclodehydration. The optically pure isomer of dianhydride was prepared by a nucleophilic substitution of optically pure (R)-(+)- or(S)-(-)-1,1′-bi-2-naphthol with 4-nitrophthalonitrile in aprotic polar solvent and subsequent hydrolysis of the resultant tetranitrile derivatives, followed by the dehydration of the corresponding tetracarboxylic acids to obtain the dianhydrides. These polymers were readily soluble in common organic solvents such as N,N-dimethylacetamide, N-methyl-2-pyrrolidone, and m-cresol, etc., and have glass transition temperatures of 251-296°C, and 5% weight loss occurs not lower than 480°C. The specific rotations of the optically active polyimides ranged from +196° to +263°, and the optical stability and chiroptical properties of them were also studied. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 3287-3297, 1997
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    Journal of Polymer Science Part A: Polymer Chemistry 35 (1997), S. 3275-3285 
    ISSN: 0887-624X
    Keywords: phenol-formaldehyde resol resin curing ; wood adhesive PF resins ; NMR of cured PF resins ; formaldehyde/phenol mol ratio of cured PF resins ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A wood adhesive-type phenol-formaldehyde (PF) resol resin synthesized with a typical formaldehyde to phenol mol ratio of 2.10 was thoroughly cured and studied by the solid-state crosspolarization/magic angle spinning 13C nuclear magnetic resonance (CP/MAS NMR) spectroscopy. The methylene group/phenol mol ratio values found were between 1.35 and 1.46, close to the value of a completely cured PF polymer structure. The amount of formaldehyde emitted during resin curing was very small. Other formaldehyde-derived groups determined from CP/MAS NMR spectra and relatively high levels of oxidation products of formaldehyde determined from water extracts of cured resin raised the total formaldehyde-derived groups/phenol mol ratio value to close to that of the synthesis mol ratio. Technological implications of these findings are discussed. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 3275-3285, 1997
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
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  • 100
    Electronic Resource
    Electronic Resource
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 35 (1997), S. 3323-3325 
    ISSN: 0887-624X
    Keywords: C60 ; radical polymerization ; methyl methacrylate ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: No abstract.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
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