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  • 1
    Electronic Resource
    Electronic Resource
    Kinetic Study of the "Living" Cationic Polymerization of Cyclohexyl Vinyl Ether Initiated by Hydrogen Iodide in the Presence of Ammonium Salts (1994)
    s.l. : American Chemical Society
    Macromolecules 27 (1994), S. 1401-1406 
    Details
    ISSN: 1520-5835
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology , Physics
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1021/ma00084a019
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  • 2
    Electronic Resource
    Electronic Resource
    Derivatization of hydroxyl into α-chloro ether: application to the synthesis of block copolymers from hydroxy-telechelic polymers (1992)
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 193 (1992), S. 2793-2806 
    Details
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: It has been recently shown that a-halogeno ether, when activated by a weak Lewis acid such as ZnX2, may be used as initiator for the living cationic polymerization of vinyl ethers. A route to the a-halogeno ether function is the action of dry hydrogen halide on an alcohol in the presence of an aldehyde or a cyclic acetal. The quantitative preparation of α-chloro ethers by this route, as well as the use of such compounds to initiate the “living” cationic polymerization of vinyl ethers, was examined. This procedure was then applied to hydroxy-telechelic polybutadiene to give a macro-initiator with α-chloro ether terminal groups. The latter was used to initiate the polymerization of vinyl ethers. The synthesis of poly(butadiene-block-ethyl vinyl ether) and poly(butadiene-block-2-chloroethyl vinyl ether) is reported, as well as the preparation of other copolymers by chemical modification of the chloroethyl vinyl ether units.
    Additional Material: 9 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/macp.1992.021931108
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  • 3
    Electronic Resource
    Electronic Resource
    Homopolymerization and copolymerization of styrene and norbornene with Ni-based/MAO catalysts (1998)
    Weinheim : Wiley-Blackwell
    Macromolecular Chemistry and Physics 199 (1998), S. 2221-2227 
    Details
    ISSN: 1022-1352
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The homopolymerization of styrene (Sty) and norbornene (NBE) was investigated in the presence of the nickel stearate (NiSt)/methylaluminoxane (MAO) catalytic system in toluene and in chlorobenzene at 20°C. The fully saturated structure of polynorbornene indicates that the two monomers polymerize by an ethylenic type addition reaction. The synthesis of true copolymers shows that one type of active species is operating for the tow monomers. Determination of reactivity ratios (rNBE = 20.8 and rSty = 0.02) indicates a much higher reactivity of NBE, which is interpreted by a coordination mechanism. The styrene-norbornene copolymers exhibit glass transition temperatures (Tg) which range from 100°C to 320°C and follow Kovacs' law. The absence of crystallinity and the homogeneous repartition of monomer units along the chains yield highly transparent materials of high thermal stability.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
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  • 4
    Electronic Resource
    Electronic Resource
    Isospecific homo- and copolymerization of styrene with ethylene in the presence of VCl3, AlCl3 as catalyst (1996)
    Weinheim : Wiley-Blackwell
    Macromolecular Rapid Communications 17 (1996), S. 461-469 
    Details
    ISSN: 1022-1336
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The homopolymerization of styrene and its copolymerization with ethylene in the presence of a vanadium-based supported catalyst, {VCI3, 1 AICI3}, associated to triethylaluminium is examined. As indicated by means of 13C nuclear magnetic resoance and differential scanning calorimetry analysis, the homopolystyrenes obtained present a highly isotactic microstructure and are semicrystalline (melting temperature 220°C).In the case of styrene/ethylene random copolymerization, the formation of both, polyethylene blocks and isotactic polystyrene sequences was identified by analysis of the crude polymer. Solubility characteristics and structural characteristics from nuclear magnetic resonance spectra of these products support the formation of copolymers with ethylene and isotactic styrene blocks rather than that of two distinct homopolymers.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/marc.1996.030170704
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  • 5
    Electronic Resource
    Electronic Resource
    Linear non-conjugated dienes from biomass as termonomers in EPDM synthesis, 3.Part 2: cf. ref.8. Conventional versus metallocene catalysis (1996)
    Weinheim : Wiley-Blackwell
    Macromolecular Chemistry and Physics 197 (1996), S. 2481-2491 
    Details
    ISSN: 1022-1352
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The synthesis in the presence of the rac-EtInd2ZrCl2/MAO catalytic system of new EPDM terpolymers based on linear non-conjugated dienes issued from biomass, 3,7-dimethylocta-1,6-diene (3,7-DMO) and 5,7-dimethylocta-1,6-diene (5,7-DMO), is described. 5,7-DMO can be readily incorporated in ethylene/propylene (E/P) chains, while 3,7-DMO does not react in the presence of the metallocene catalyst. The reactivity of these linear dienes is compared with that of 2-ethylidenebicyclo[2.2.1]hept-5-ene (ENB), the preferred termonomer for the industrial synthesis of EPDMs. With the metallocene catalyst, the reactivity of 5,7-DMO is close to that of ENB, suggesting that 5,7-DMO is a good candidate for the synthesis of a new EPDM. A comparison with the conventional catalysis based on vanadium systems shows that the advantages of the metallocene catalysis consist in higher catalyst activities and higher incorporation rates of the termonomers in the polymer without any noticeable side reaction. The structural and physico-chemical characteristics of the various terpolymers, investigated by NMR, SEC and DSC, also underline that the use of metallocenes allows one to prepare EPDM based on linear dienes, with an homogeneous chemical composition and a controlled structure.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/macp.1996.021970812
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  • 6
    Electronic Resource
    Electronic Resource
    ω-Chloro-α-olefins as co- and termonomers for the synthesis of functional polyolefins (1997)
    Weinheim : Wiley-Blackwell
    Macromolecular Chemistry and Physics 198 (1997), S. 291-303 
    Details
    ISSN: 1022-1352
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: This paper deals with the use of ω-chloro-α-olefins as monomers for the synthesis of chloro-functional homo-, co- and terpolyolefins in the presence of (IVb) metallocene/MAO catalytic systems. Two ω-chloro-α-olefins, 11-chloroundec-1-ene and 5-chloropent-1-ene, were tested. It was found that only the functional olefin containing the longer aliphatic spacer between the alkene function and the halide polymerizes readily in the presence of the rac-Et(Ind)2ZrCl2/MAO catalyst. The drastic influence of the reaction solvent on the chloro-olefin reactivity and (co)polymerization behavior is examined and discussed. Finally, the terpolymerization of 11-chloroundec-1-ene with ethylene and propene is investigated. In a second part, the quantitative preparation, by derivatization of 11-chloroundec-1-ene units, of functional polyolefins bearing benzoate, hydroxy or azido functions as side groups is described. The corresponding functional polymers are characterized by IR and 1H NMR spectroscopy.
    Additional Material: 9 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/macp.1997.021980206
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  • 7
    Electronic Resource
    Electronic Resource
    Amphiphilic block copolymers of controlled dimensions with hydrophilic glycosidic vinyl ether moieties (1998)
    Weinheim : Wiley-Blackwell
    Macromolecular Chemistry and Physics 199 (1998), S. 335-342 
    Details
    ISSN: 1022-1352
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: New amphiphilic diblock copolymers of controlled dimensions constituted of styrene and hydrophilic glycosidic vinyl ether moieties were prepared and their emulsifying properties examined. The hydrophobic block was obtained by living anionic polymerization of styrene, followed by a quantitative functional termination with chloroacetal derivatives. The polystyrene chain ends were then derivatized, by addition of trimethylsilyl iodide, into α-iodo ether macro-initiators. The latter were used to initiate the “living” cationic polymerization of protected glycosidic vinyl ethers, in the presence of weak Lewis acids (typically ZnCl2). The amphiphilic copolymers were obtained by deprotection, in acidic medium, of the hydroxy functions of the sugar of the moieties. The solubility characteristics of these copolymers are discussed with respect to the dimensions of the copolymers and to the hydrophilic/hydrophobic balance between the two blocks.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
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  • 8
    Electronic Resource
    Electronic Resource
    Linear non-conjugated dienes from biomass as termonomers in EPDM synthesis, 2.Part 1: cf. ref.9. Comparison with 5-ethylidene-2-norbornene termonomer (1996)
    Weinheim : Wiley-Blackwell
    Macromolecular Chemistry and Physics 197 (1996), S. 289-302 
    Details
    ISSN: 1022-1352
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: A comparative study of 5-ethylidene-2-norbornene (ENB) or 5,7-dimethylocta-1,6-diene (5,7-DMO) as diene termonomer in ethylene-propylene-diene (EPDM) terpolymer synthesis is presented. The reactivities of the cyclic and linear non-conjugated dienes are first compared in homopolymerization in the presence of two conventional Ziegler-Natta catalytic systems: TiCl3, 1/3AlCl3, 14MgCl2 associated to AlEt3, and VOCl3 (or VCl4) associated to AlEt2Cl. ENB polymerization yields a branched poly(ENB) in agreement with a predominant cationic reaction, whereas polymerization of 5,7-DMO proceeds exclusively by a Ziegler-Natta mechanism. In terpolymerization, ENB is much more reactive than 5,7-DMO and is incorporated more easily in the terpolymer. However, the high sensitivity of ENB toward acidic species also results in cationic side reactions and therefore limits the utilization of ENB to a low concentration range. We have shown that the productivity of vanadium catalysts, which are mainly used in industrial EPDM synthesis, is drastically reduced in the presence of ENB an 5,7-DMO, due to the rapid reduction of vanadium involving the diene.
    Additional Material: 10 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/macp.1996.021970122
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  • 9
    Electronic Resource
    Electronic Resource
    Linear non-conjugated dienes from biomass as termonomers in EPDM synthesis, 1. Study of their reactivity in homo-, co- and terpolymerizations (1995)
    Weinheim : Wiley-Blackwell
    Macromolecular Chemistry and Physics 196 (1995), S. 3091-3105 
    Details
    ISSN: 1022-1352
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: This paper deals with the use of 3,7-dimethylocta-1,6-diene (3,7-DMO) and 5,7-dimethylocta-1,6-diene (5,7-DMO), issued from terpene feedstock, as termonomers for the synthesis of ethylene-propylene-diene terpolymers (EPDM). Their reactivity is first compared to 7-methylocta-1,6-diene (MOCD), an industrial linear diene, in homopolymerization and cross-copolymerization. Two catalytic systems are used: TiCl3, 1/3AlCl3, 14 MgCl2 associated with Al(C2H5)3, and VOCl3 or VCl4 associated with Al(C2H5)2Cl. The influence of the diene structure on the observed order of reactivity is discussed. In a second part, the copolymerization and the terpolymerization of the different dienes with ethylene and propene are implemented. A drastic influence of the diene structure and concentration on the productivity (and activity) is observed. Potentiometric titrations of the vanadium, performed both in the absence and in the presence of dienes (and of other substituted olefins), indicate that the productivity loss mainly results from a reduction process of the vanadium, involving the di- or trisubstituted olefins
    Additional Material: 9 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/macp.1995.021961002
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  • 10
    Electronic Resource
    Electronic Resource
    Living cationic polymerization of cyclohexyl vinyl ether (1994)
    Weinheim : Wiley-Blackwell
    Macromolecular Chemistry and Physics 195 (1994), S. 217-227 
    Details
    ISSN: 1022-1352
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The cationic polymerization of cyclohexyl vinyl ether (CHVE) initiated by α-halogeno ethers in the presence of a Lewis acid activator has been investigated first. In conditions leading to a living polymerization of alkyl vinyl ethers (ethyl, isobutyl, etc.), an extremely fast polymerization, accompanied by chain transfer reactions, is observed with CHVE. In fact, we have shown that the polymerization of this monomer may be directly initiated by the HI and HCl adducts of CHVE, in the absence of any electrophilic activator. However, even in these conditions, the polymerization cannot be controlled. A “living” polymerization of CHVE was finally obtained by addition of ammonium salts (NBu4X; X = Cl, Br, I) to the systems free of electrophilic activators. The added salts stabilize the α-halogeno ether chain ends and reduce the overall reactivity. Using this procedure, we have synthesized poly(CHVE)s with M̄n's ranging from 6 · 103 to 4 · 104 g · mol-1 (in good agreement with the predicted values assuming the formation of one polymer chain per initiator molecule) and narrow molecular weight distributions (M̄w/M̄n 〈 1,2). Though most of poly(alkyl vinyl ether)s exhibit glass transition temperatures far below 0°C, the glass transition temperature of the poly(CHVE) is close to +50°C, indicating that this monomer can be used as a precursor to rigid poly(vinyl ether) blocks.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/macp.1994.021950120
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