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  • 1
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 177 (1976), S. 621-629 
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Description / Table of Contents: Poly{1-[3-(9-carbazolyl)propylaminocarbonyl]äthylen} {Poly[N-(3-acryloylaminopropyl)carbazole]} (6) wurde durch radikalische Polymerisation des entsprechenden Monomers 5 hergestellt. Aus Copolymerisationsversuchen von 5 (M1) und Styrol (M2) wurden sowohl die Copolymerisationsparameter r1 und r2 als auch die Q-e Werte für 5 erhalten (r1 = 0,13±0,08, r2 = 3,47±0,12; Q = 0,18, e = 0,10). Das Fluoreszenzspektrum von 6 ist mit demjenigen der Modellsubstanz N-(3-Isobutyrylaminopropyl)carbazole (2) fast identisch, was auf die Abwesenheit von intramolekularen Excimeren im Polymer 6 hindeutet. Die Stabilitätskonstanten K der aus 6 oder 2 und 2,4,7-Trinitrofluorenon (TNF) gebildeten Chargetransfer-Komplexe wurden in Dichlorethan bei 20°C, unter den Bedingungen, daß [6] oder [2]≫[TNF] und 6 oder 2≪[TNF], ermittelt. Die Werte sind K = 4,9 bzw. 5,2 dm3mol-1 für 2, wenn [2]≫[TNF] bzw. [2]≪[TNF], und 16dm3mol-1 für 6, wenn [6]≫[TNF]. Das Polymer 6 fallt jedoch aus, wenn [6]≪[TNF]. Zum Vergleich wurde auch die Chargetransfer-Bildung von Poly[1-(9-carbazolyl)äthylen] [Poly(N-vinylcarb azol)] (1) mit TNF unter denselben Bedingungen untersucht, wobei dieselben Werte für K gefunden wurden, wenn [1]≫[TNF] und [1]≪[TNF]. Zur Erklärung kann man annehmen, daß sich bei 6 sandwichartige Chargetransfer-Komplexe bilden, wahrend sich bei 1 keine derartigen Komplexe bilden können, da aus Platzmangel zwischen die Carbazolyl-Gruppen in 1 kein TNF-Molekül eingesetzt werden kann.
    Notes: A new carbazole polymer, poly{1-[3-(9-carbazolyl)propylaminocarbonyl]ethylene} {poly[N-(3-acryloylaminopropyl)carbazole]} (6) was prepared by radical polymerization of N-(3-acryloylaminopropyl)carbazole (5). Copolymerization of 5 (M1) with styrene (M2) provided the monomer reactivity ratios r1 = 0,13±0,08 and r2 = 3,47±0,12. The Q-e values of 5 were calculated as Q1 = 0,18 and e1 = +0,10. Fluorescence spectra of 6 and N-(3-isobutyrylaminopropyl)carbazole (2), prepared as a monomer model compound, were nearly identical, indicating the absence of intramolecular excimer formation for 6. The stability constants (K) of the charge transfer complexes of 6 and 2 with 2,4,7-trinitrofluorenone (TNF) were determined in 1,2-dichloroethane at 20°C under the conditions of both [6] or [2]≫[TNF] and [6] or [2]≪[TNF]. The values of K were 4,9 and 5,2dm3 mol-1 for 2 when [2]≫[TNF] and [2]≪[TNF], respectively, and 16dm3 mol-1 for 6 when [6]≫[TNF]. The polymer 6 precipitated, however, when [6]≪[TNF]. As a reference, charge transfer complex formation of poly[1-(9-carbazolyl)-ethylene] [poly(N-vinylcarbazole)] [1] with TNF was studied under the same conditions. The values of K for 1 were identical when [1]≫[TNF] and [TNF]. These results were explained by assuming a sandwich-type charge transfer complex for 6, but not for 1. The space between the carbazolyl groups in 1 would be too small to accomodate a TNF molecule between the chromophores.
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  • 2
    Electronic Resource
    Electronic Resource
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 24 (1986), S. 2971-2980 
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Thermolysis of poly(p-t-butoxycarbonyloxystyrene) (PBOCST) catalyzed by polymeric phenol in the solid state is very much dependent on the extent of phase separation. Poly(p-hydroxystyrene) (PHOST, a thermolysis product of PBOCST) is not miscible with PBOCST. Therefore, this phenolic resin can not effectively catalyze the solid-state thermolysis reaction when simply blended with PBOCST. However, if the phenolic functionality is forced to be in the vicinity of the t-butoxycarbonyl (tBOC) group, the thermolysis takes place facilely at 130°C. The effect of casting solvent on thermolysis in PBOCST/Varcum films is also discussed.
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  • 3
    Electronic Resource
    Electronic Resource
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 28 (1990), S. 2597-2607 
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: N-phenyl-α-methylene-β-lactam (PML), a cyclic analog of N,N-disubstituted methacrylamides which do not undergo radical homopolymerization, was synthesized and polymerized with α,α′-azobis (isobutyronitrile) (AIBN) in solution. Poly (PML) (PPML) is readily soluble in tetrahydrofuran, chloroform, pyridine, and polar aprotic solvents but insoluble in toluene, ethyl acetate, and methanol. PPML obtained by radical initiation is highly syndiotactic (rr = 92%), exhibits a glass transition at 180°C, and loses no weight upto 330°C in nitrogen. The kinetics of PML homo-polymerization with AIBN was investigated in N-methyl-2-pyrrolidone. The rate of polymerization (Rp) can be expressed by Rp = k[AIBN]0.55[PML]1.2 and the overall activation energy has been calculated to be 87.3 kJ/mol. Monomer reactivity ratios in copolymerization of PML (M2) with styrene (M1) are r1 = 0.67 and r2 = 0.41, from which Q and e values of PML are calculated as 0.60 and 0.33, respectively.
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  • 4
    Electronic Resource
    Electronic Resource
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 31 (1993), S. 949-955 
    ISSN: 0887-624X
    Keywords: radical polymerization ; 3-methylene-5,5′-dimethyl-2-pyrrolidinone ; exomethylene cyclic monomers ; kinetics ; monomer reactivity ratios ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: 3-Methylene-5,5′-dimethyl-2-pyrrolidinone (α-MDMP), a cyclic analog of N-substituted methacrylamide, was synthesized and polymerized with α,α′-azobis (isobutyronitrile) (AIBN) in solution. Poly(α-MDMP) is only soluble in dimethyl sulfoxide (DMSO) at room temperature. Thermogravimetry of poly(α-MDMP) showed 10% weight loss at 355°C in air and 400°C under nitrogen, respectively. The kinetics of α-MDMP homopolymerization with AIBN was investigated in DMSO. The rate of polymerization (Rp) can be expressed by Rp = k[AIBN]0.49[α-MDMP]1.0 and the overall activation energy has been calculated to be 73.2 kJ/mol. Monomer reactivity ratios in copolymerization of α-MDMP (M2) with methyl methacrylate (M1) are r1 = 0.71 and r2 = 0.71, from which Q and e values of α-MDMP are calculated as 0.75 and -0.43, respectively. © 1993 John Wiley & Sons, Inc.
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  • 5
    Electronic Resource
    Electronic Resource
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 31 (1993), S. 1895-1902 
    ISSN: 0887-624X
    Keywords: 4-methylene-4H-1,3-benzodioxin-2-one ; exo-methylene cyclic monomers ; radical polymerization ; kinetics ; monomer reactivity ratios ; chemical amplification ; decarboxylation ; poly[(o-hydroxyphenyl)acetylene] ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: 4-Methylene-4H-1,3-benzodioxin-2-one (MBDOON), an α-substituted cyclic styrene derivative, was synthesized and polymerized readily with 2,2′-azobis(isobutyronitrile) (AIBN) as an initiator in solution. The kinetics of the MBDOON homopolymerization with AIBN was investigated in N-methyl-2-pyrrolidone (NMP). The rate of polymerization, Rp, can be expressed by Rp - k[AIBN]0.52[MBDOON]1.1 and the overall activation energy has been calcualted to be 75.7 kJ/mol. Monomer reactivity ratios in copolymerization of MBDOON (M2) with styrene (M1) are r1 = 0.31 and r2 = 3.20, from which Q and e values of MBDOON can be calculated as 3.0 and -0.7, respectively. Ring-substituted MBDOON monomers such as 6-chloro, 6-methyl, and 7-methoxy derivatives were synthesized and polymerized with AIBN. The 6-substituted MBDOON's readily underwent radical polymerization while the 7-methoxy-MBDOON was slower to polymerize. Poly(MBDOON) is predominantly heterotactic. (rr = 35, mr = 46, and mm = 19%). The polymer releases carbon dioxide at about 200°C and is converted with some depolymerization to poly[(o-hydroxyphenyl)acetylene]. The thermolysis temperature is very much affected by the ring substituent. The onset of carbon dioxide liberation was observed at 140°C in the case of the 7-methoxyl derivative while the 6-substituents had a smaller effect on the decarboxylation temperature. © 1993 John Wiley & Sons, Inc.
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  • 6
    Electronic Resource
    Electronic Resource
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 33 (1995), S. 1059-1067 
    ISSN: 0887-624X
    Keywords: radical polymerization ; methyl trans-β-vinylacrylate ; kinetics propagation radical ; monomer reactivity ratios ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Methyl trans-β-vinylacrylate (MVA) undergoes radical polymerization with α,α′-azobis(isobutyronitrile) (AIBN) in bulk and solution. The polymer obtained consists of 85% trans-1,4 and 15% trans-3,4 units. Poly(MVA) (PMVA) is readily soluble in common organic solvents, but insoluble in n-hexane and petroleum ether. PMVA exhibits a glass transition at 60°C, and loses no weight up to 300°C in nitrogen. The kinetics of MVA homopolymerization with AIBN was investigated in benzene. The rate of polymerization (Rp) can be expressed by Rp = k[AIBN]0.5[MVA]1.0, and the overall activation energy has been calculated to be 94 kJ/mol. The propagation radical of MVA at 80°C was detected by ESR spectroscopy, which indicated that the unpaired electron of the propagating radical was completely delocalized over the three allyl carbons. Furthermore, the steady-state concentration of the propagating radical of MVA at 60°C was determined by ESR spectroscopy, and the propagation rate constant (kp) was calculated to be 1.25 X 102 L/mol ·s. Monomer reactivity ratios in copolymerization of MVA (M2) with styrene (M1) are r1 = 0.16 and r2 = 4.9, from which Q and e values of MVA are calculated as 4.2 and -0.32, respectively. © 1995 John Wiley & Sons, Inc.
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  • 7
    Electronic Resource
    Electronic Resource
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 24 (1986), S. 955-964 
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Alternating copolymers of styrene (St) with electron-deficient olefins trisubstituted or tetrasubstituted with cyano and carboalkoxy groups have been subjected to 60Co γ-radiolysis together with a series of copolymers of methyl methacrylate (MMA) and St. The chain scission susceptibility Gs - Gx determined by membrane osmometry drastically decreases as St is incorporated in poly(methyl methacrylate) (PMMA). Whereas the alternating St-MMA copolymer is slightly crosslinked upon irradiation, an alternating copolymer of St with diethyl 2-cyano-1,1-ethylenedicarboxylate maintains a fairly high degradation sensitivity (Gs - Gx = 1.2). The reactive-ion etch rates were determined for the series of polymers in CF4/O2 (92/8). The etch resistance is significantly increased by introduction of St units in PMMA, and the highly substituted alternating copolymer etches as slowly as the MMA(50) - St(50) copolymers. Thus the alternating copolymer of NCCH=C(CO2Et)2 with St behaves like PMMA when exposed to high-energy radiation but is comparable to PSt in plasma environments.
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  • 8
    Electronic Resource
    Electronic Resource
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 29 (1991), S. 1779-1787 
    ISSN: 0887-624X
    Keywords: α-methyleneindane ; tacticities ; monomer reactivity ratios ; exo-methylene cyclic monomers ; depropagation ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: α-Methyleniedane (MI), a cyclic analog of α-methylstyrene which does not undergo radical homopolymerization under standard conditions, was synthesized and subjected to radical, cationic, and anionic polymerizations. MI undergoes radical polymerization with α,α′-azobis(isobutyronitrile) in contrast to α-methylstyrene, owing to its reduced steric hindrance, though the polymerization is slow even in bulk. Cationic and anionic polymerization of MI with BF3OEt2 and n-butyllithium, respectively, proceed rapidly. The thermal degradation behavior of the polymer depends on the polymerization conditions. The anionic and radical polymers are heteortactic-rich. Reactivity ratios in bulk radical copolymerization on MI (M2) with methacrylate (MMA, M1) were determined at 60°C (r1 = 0.129 and r2 = 1.07). In order to clarify the copolymerization mechanism, radical copolymerization of MI with MMA was investigated in bulk at temperatures ranging from 50 to 80°C. The Mayo-Lewis equation has been found to be inadequate to describe the result due to depolymerization of MI sequences above 70°C.
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  • 9
    Electronic Resource
    Electronic Resource
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 26 (1988), S. 89-98 
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: α-Trifluoromethylstyrene (TFMST) does not undergo radical homopolymerization with azobis(isobutyronitrile) (AIBN) in bulk at 60°:C. Low-temperature initiation was not effective either. Radical copolymerization of TFMST (M2) with styrene (ST, M1) has yielded monomer reactivity ratios as follows: r1 =: 0.60 and r2 =: 0.00. It has been found that the cyclohexyl radical generated by reaction of cyclohexylmercuric chloride with sodium borohydride adds to the β-carbon of TFMST 7.5 times faster than that of ST. Combination of the copolymerization analysis and the “mercury method” has allowed us to estimate Alfrey-Price Q and e parameters for TFMST to be 0.43 and 0.90, respectively. Thus, due to the strongly electron-withdrawing effect of the trifluoromethyl group, this styrene is highly electron deficient. In spite of the favorable electronic effect, however, the ceiling temperature appears very low, presumably due to the steric hindrance.
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  • 10
    Electronic Resource
    Electronic Resource
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 26 (1988), S. 2395-2404 
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Reactivities of methyl methacrylate derivatives bearing substituents on the ester methyl group have been investigated by competitively adding a cyclohexyl radical generated by a reaction of cyclohexylmercuric chloride with sodium borohydride (mercury method) to these substituted methacrylates and methyl methacrylate or styrene. The relative rate constants of the cyclohexyl radical addition have been found to be nicely correlated with parameters such as Traft α* constants of alkyl esters, Q-e values, lowest unoccupied molecular orbital energies, β-carbon chemical shifts, and relative reactivities toward a polystyryl radical, indicating that the mercury method is a simple and useful technique for evaluation of the relationship between structure and reactivity of vinyl monomers in their radical polymerization, even when the structural modification is small.
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