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  • 1
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 180 (1979), S. 2793-2796 
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
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  • 2
    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: Kationische Polymerisationen von Vinyloxyäthylacrylat (VEA), katalysiert durch den Bortrifluorid-Äther-Komplex, wurden in Toluol bei 10, -10 und -30°C durchgeführt. In diesem System gibt es eine kritische Katalysatorkonzentration (Co), unterhalb derer die Polymerisation von VEA nicht initiiert werden kann.Für die Geschwindigkeit der Polymerisation wurde folgende Gl. gefunden: -d[M]/dt=kp(C*)·[M]a, und für a die Werte 0,44 bei 10°C; 0,51 bei -10°C und 0,63 bei -30°C.Aus diesen Ergebnissen wurde geschlossen, daß die Polymerisationsgeschwindigkeit von VEA proportional ist zur 1. Potenz der Katalysatorkonzentration und zu einer Potenz von 0,44-0,63 der Monomerkonzentration zwischen 10 und -30°C.Außerdem konnte festgestellt werden, daß zunehmende Monomerkonzentration zur Abnahme des Polymerisationsgrades führt.
    Notes: Cationic polymerizations of vinyloxyethyl acrylate (VEA) catalyzed by boron trifluorideether complex were carried out in toluene at 10, -10, and -30°C. In this system, a critical catalyst concentration (C0) exists; when the catalyst concentration is below this concentration, the polymerization of VEA cannot be initiated. The rate of polymerization is expressed as -d[M]/dt=kp(C*)·[M]a, where a was found to be 0,44 (at 10°C), 0.51 (at -10°C), and 0,63 (at -30°C), respectively.From these results, it is concluded that the rate of polymerization of VEA is proportional to the first power of catalyst concentration and to 0,44-0,63 power of monomer concentration between 10 and -30°C, respectively.Furthermore, it is recognized that an increasing monomer concentration tends to decrease the degree of polymerization.
    Additional Material: 11 Ill.
    Type of Medium: Electronic Resource
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  • 3
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 180 (1979), S. 2789-2792 
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
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  • 4
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Self-sensitized photosensitive polymers with pendant photosensitive and photosensitizing groups were prepared by reaction of polystyrene containing pendant chloromethyl and photosensitizing groups, with the potassium salts of photosensitive compounds such as cinnamic acid, crotonic acid, or 2-cyano-3-(α-styryl)acrylic acid in DMF using tetrabutylammonium bromide as phase transfer catalyst. The photochemical reactivity and the practical photosensitivity of the resulting polymers were measured by IR spectrometry and by the gray-scale method, respectively. Pendant 4-nitro-1-naphthyloxy and 4-nitrophenoxy groups in the polymers show the highest photosensitizing activity for pendant cinnamoyl groups. The photochemical reactivity and the sensitivity of these polymers are affected by the content of photosensitizing units in the polymer skeleton, the glass transition temperature of the polymers, however, is not influenced. Pendant 2-benzoylbenzoyl groups act as excellent photosensitizers for pendant crotonoyl groups, however, the photochemical reactivity of this polymer was found to be lower than that of the polymer with pendant cinnamoyl and suitable photosensitizing groups. Pendant 2-cyano-3-(α-styryl)acryloyl groups in the polymer, which exhibit high photochemical activity, are also sensitized by pendant methyleosin moieties.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
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  • 5
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Alternating copolymers with amide and thioether linkages were synthesized by addition reactions of bisoxazolines 1a - 1f and bisoxazines 2a and 2b with dithiols 3a - c in aprotic polar solvents. The reactions of the aromatic bifunctional cyclic iminoethers such as 1a, 1c, 2a, and 2b with the dithiols 3a and 3c in N-methyl-2-pyrrolidone gave polymers with high molecular weight. However, the reactions of the aliphatic derivatives such as 1e and 1f with dithiols as well as the reactions of the bifunctional cyclic iminoethers with 3b led to polymers of low molecular weights. The reactions of methyl substituted bisoxazolines 1b and 1d with dithiols gave also polymers of low molecular weight.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
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  • 6
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Poly[1-(2-oxazoline-2-yl)ethylene] (2a), poly[1-(5-methyl-2-oxazoline-2-yl)ethylene] (2b), poly[1-(4,4-dimethyl-2-oxazoline-2-yl)ethylene] (2c), poly[1-(4,4-dimethyl-5,6-dihydro-4H-1,3-oxazine-2-yl)ethylene] (2d), and poly[1-(4,4,6-trimethyl-5,6-dihydro-4H-1,3-oxazine-2-yl)ethylene] (2e) were synthesized with high yields by radical polymerization, using AIBN as initiator. Polymer 2a was found to be soluble in water and in organic solvents such as methanol, acetone, chloroform and benzene, polymer 2b in hot water and in the same organic solvents, and polymers 2c and 2d are insoluble in cold and hot water. However, polymers 2d and 2e are soluble in diethyl ether and hexane. Addition reactions of polymers 2a-e with carboxylic acids and thiols were investigated. Reactions of polymer 2a with acetic acid, benzoic acid and cinnamic acid at 110°C for 10 h proceeded with 57-74 mol-% conversion in DMF, NMP and DMSO, and reactions with benzenethiol and thiobenzoic acid quantitatively under the same reactions conditions. Reactions of polymers 2b and 2c with carboxylic acids proceeded with 4-36 mol-% conversion, and with benzenethiol and thiobenzoic acid with 80-96 mol-% conversion. From the results the following order of reactivities of these polymers may be suggested: 2a ≃ 2d 〉 2e 〉 2b 〉 2c. According to their higher nucleophilicity, the reactivities of benzenethiol and thiobenzoic acid towards the pendant 2-oxazoline ring are much higher than those of carboxylic acids.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
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  • 7
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Rates of photochemical reactions of polymers containing pendant cinnamic ester moieties and photosensitizing 4-nitrophenoxy or 4-nitro-1-naphthyloxy groups were determined in dilute benzene and tetrahydrofuran solutions. The rate of photodimerization of the polymers obeys first order kinetics in diluted solution and is affected by the type and content of pendant photosensitizing groups and by the structure of the polymer skeleton. By comparison of the rate of photodimerization of three homopolymers and six copolymers, it could be concluded that the polymers consisting of flexible segments have a higher rate of photodimerization than those made of rigid segments.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
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  • 8
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 188 (1987), S. 2105-2110 
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The photochemical addition reaction of poly(oxy-1-methyleneethylene-co-oxy-1-chloromethylethylene) (1), a polymer containing vinyl ether groups and synthesized by partial elimination reaction of poly(epichlorohydrin)Poly(oxy-1-chloromethylethylene)., with methyl 3-mercaptopropionate was carried out using benzophenone (BP) as a photosensitizer. The addition reaction proceeds with high conversion in benzene, toluene and tetrahydrofuran (THF). However, the degree of addition in both 1,4-dioxane and N-methyl-2-pyrrolidone (NMP) is relatively low, and the reaction does not proceed in dimethyl sulfoxide (DMSO) under the same reaction conditions. An optically active polymer containing pendant amino acid moieties was also synthesized by the photochemical reaction of polymer 1 with N-acetyl-L-cysteine using BP as a photosensitizer in THF. It was found that the specific angle of rotation of the obtained polymer increases with increasing degree of conversion.
    Additional Material: 2 Ill.
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  • 9
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Some multifunctional polymeric photosensitizers containing both pendant photosensitizing groups and substrate-attracting groups were synthesized by partial substitution reaction of poly(chloromethylstyrene) with potassium 4-nitrophenoxide under the conditions of phase transfer catalysis, followed by addition reactions of the resulting polymer with various kinds of tert-phosphines or amines. The reactivity of tert-phosphine was found to decrease with increasing lenght of the alkyl chain in the tert-phosphine. However, the addition reaction of the polymer with tert-phosphines and -amines proceeded quantitatively at 80°C for 48 h in DMF, respectively. The photo-isomerization of potassium cinnamate (PCIN) was carried out using the multifunctional polymeric photosensitizers in methanolic aqueous solution. The polymeric photosensitizer (polymer 3) containing the small and hydrophilic substrate-attacting benzyltri-ethylphosphonium chloride moiety showed a higher efficiency than the polymers (polymers 5 and 7) containing bulky and hydrophobic substrate-attracting moieties like benzyltributyl- or benzyltrioctylphosphonium chloride. Polymer 3 has the highest efficiency at a content of 10 mol-% of pendant 4-nitrophenoxy (NP) moieties, and polymers 5 and 7 have their highest efficiency at a content of 15 mol-% of pendant NP moieties. Polymeric photosensitizers containing pendant quaternary phosphonium salts as the substrate-attracting group have a higher efficiency than the polymers containing pendant quaternary ammonium salts. Further more, the rate of photo-isomerization of PCIN was found to be strongly affected by the concentration of the polymeric photosensitizers in solution, and also by the polarity of the reaction medium.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
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  • 10
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 180 (1979), S. 2023-2026 
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Additional Material: 1 Tab.
    Type of Medium: Electronic Resource
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