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  • 1
    ISSN: 1434-4475
    Keywords: Functional polymers ; 2(2-Hydroxyphenyl)2 H-benzotriazoles ; 2-Hydroxyphenylaceto(benzo)phenones ; Azo coupling ; Reductive cyclization ; Ultraviolet stabilizers
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung Es wurden acht Benzotriazole und 4-Methoxybenzotriazole — mono- oder disubstituierte Derivate von 2,4-Dihydroxyaceto(oder benzo)phenonen — über Azokopplung von 4-Methoxy-2-nitrobenzoldiazoniumchlorid mit 2,4-Dihydroxyaceto(oder benzo)phenonen und nachfolgender reduktiver Cyclisierung synthetisiert. Reine monosubstituierte Verbindungen waren sehr schwer herzustellen. Sorgfältige Wahl despH-Wertes für die Azo-Kupplung und geeignete Reagentien für die reduktive Cyclisierung waren dabei wesentlich. Alle Verbindungen wurden mittels UV-, IR-,1H-NMR- und13C-NMR-Spektren und Elementaranalysen charakterisiert. Die synthetisierten Verbindungen besitzen jeweils eine 2-(2-Hydroxyphenyl)-2H-benzotriazol-Einheitund eine 2-Hydroxyaceto(oder benzo)phenon-Einheit im gleichen Molekül und stellen effektvolle und nützliche Ultraviolett-Absorber dar.
    Notes: Abstract Eight benzotriazoles and (4-methoxy)benzotriazoles, mono- or di-substituted derivatives of 2,4-dihydroxyaceto(or benzo)phenone were synthesized by azo coupling of (4-methoxy)2-nitrobenzenediazonium chloride with 2,4-dihydroxyaceto(or benzo)phenone followed by reductive cyclization. Pure mono-substituted compounds were very difficult to prepare. Careful selection of thepH for the azo coupling and selection of the proper reagents for the reductive cyclization were essential. All compounds were characterized by their ultraviolet, infrared1H and13C NMR spectra and their elemental analysis. These compounds have both the 2(2-hydroxyphenyl)2H-benzotriazole unit and a 2-hydroxyaceto(or benzo)phenone unit in the same molecule and are effective and useful ultraviolet absorbers.
    Type of Medium: Electronic Resource
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  • 2
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The synthesis of 2(2-hydroxy-5-methylphenyl)-5-vinyl-2H-benzotriazole was accomplished in seven steps starting from 4-ethylaniline. Acetylation and nitration followed by hydrolysis gave 2-nitro-4-cthylaniline which was diazotized, condensed with p-cresol, and reduced to 2(2-hydroxy-5-methylphenyl)-5-ethyl-2H-benzotriazole. As in previous cases, the ethyl group was transformed to the vinyl compound by bromination with N-bromosuccinimide and dehydrobromination of the 1-bromoethyl compound. Monomer grade 2(2-hydroxy-5-methylphenyl)-5-vinyl-2H-benzotriazole was polymerized and copolymerized with styrene, methyl methacrylate, and n-butyl acrylate.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
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  • 3
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Successful grafting of 2(2-hydroxy-5-vinylphenyl)2H-benzotriazole onto saturated aliphatic C—H groups of polymers has been accomplished. When the grafting reaction was carried out in chlorobenzene at 150-160°C with di-tertiary butylperoxide as the grafting initiator, grafts as high as 20-30% at grafting efficiencies of 50 and 80% have readily been obtained. It was very important to carry out the grafting reaction in tubes sealed under high vacuum since trace amounts of oxygen cause complete inhibition of the grafting reaction by the phenolic monomer. Grafting reactions were carried out on a variety of different polymers including atactic polypropylene, ethylene/vinyl acetate copolymer, poly(methyl methacrylate), poly(butyl acrylate), and polycarbonate.
    Additional Material: 1 Ill.
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  • 4
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 2629-2648 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Head-to-head polyisobutylene of molecular weight 3000 to 10,000 was prepared in about 30% yield by Grignard coupling polymerization of 2,2,3,3-tetramethyl-1,4-dibromobutane with copper(I) tris(triphenylphosphino)bromide as the catalyst. Head-to-head polyisobutylene is crystalline, with a Tm of 187°C and a Tg of 87°C and still has bromine end groups left. The polymers have been characterized by their infrared, 1H-, and 13C-NMR spectra and compared to the corresponding head-to-tail polymers of similar molecular weight. A substantial portion of the reaction product of the Grignard coupling polymerization is not polymeric but was identified as cyclized product, 1,1,2,2-tetramethylcyclobutane.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
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  • 5
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 2713-2725 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Acrylonitrile was terpolymerized with styrene and 2,4,6-tribromophenyl acrylate in aqueous emulsion and dimethylformamide solution. Experimental terpolymerization data agreed well with calculations based on the Alfrey-Goldfinger equation. Triangular coordinate graphs show the feed/terpolymer relationships; the lines of unique and binary azeotropic compositions were identified. No points of true azeotropic composition were found but a “pseudo-azeotropic” region was recognized. The experimental data of the emulsion terpolymerization experiment agreed well with the theoretical curves over a wide range of monomer compositions up to high conversions. Incorporation of 2,4,6-tribromophenyl acrylate in the terpolymer decreased the thermal stability but improved the flame retardancy of the terpolymers.
    Additional Material: 13 Ill.
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  • 6
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 1913-1928 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The terpolymerization of acrylonitrile with styrene and 2,3-dibromopropyl acrylate in emulsion and dimethyl formamide solution was investigated. Polymerizations, when stopped at low conversions, yielded terpolymers that showed good agreement between experimental and theoretical copolymerization composition data, calculated from the Alfrey-Goldfinger equation. The relationship between monomer feed and terpolymer compositions is displayed on triangular coordinate graphs proposed by Slocombe. By using a computer program the lines of unique composition and binary azeotropic composition for both systems were established. In the case of emulsion polymerization the azeotropic ternary point was determined at a molar ratio for acrylonitrile/styrene/2,3-dibromopropyl acrylate of 0.27/0.61/0.12. The experimental results of emulsion terpolymerization fit the calculated curves satisfactorily over a wide range of monomer compositions up to high conversions. The influence of 2,3-dibromopropyl acrylate on the thermal and flammability characteristics of the terpolymers is described.
    Additional Material: 15 Ill.
    Type of Medium: Electronic Resource
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  • 7
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 2501-2521 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: ω-Alkenoic acids, either commercially available or synthesized, were esterified to their corresponding methyl esters. They were characterized by their infrared, 1H-, and 13C-NMR spectra. The ω-alkenoates prepared were: propenoate (acrylic acid), butenoate, pentenoate, hexenoate, heptenoate, octenoate, nonenoate, and decenoate. These compounds were epoxidized with m-chloroperoxybenzoic acid to the corresponding methyl ω-epoxyalkanoates. The rate of epoxidation of the double bond is found to increase as the double bond is separated from the carbomethoxy group by increasing numbers of methylene groups. When at least three methylene groups are inserted, the rate of epoxidation becomes constant and is similar to the epoxidation of ω-olefins. The methyl ω-epoxyalkanoates were characterized by their infrared, 1H-, and 13C-NMR spectra. Methyl ω-alkenoates and methyl ω-epoxyalkanoates were prepared and characterized, and their purification was studied in preparation for their investigation as monomers for olefin or epoxide polymerization using corrdination initiators.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
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  • 8
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 2477-2499 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Biuret oligomers and polymers from primary aliphatic amines and aromatic or aliphatic diisocyanates have been synthesized. To demonstrate the feasibility of the synthesis of polybiurets, aliphatic primary amines with n-propyl, n-hexyl, n-octyl, and n-dodecyl groups have been incorporated. For the synthesis of biuret oligomers of biologically active primary aliphatic amines [8-(4-amino-1-methylbutylamino)-6-methoxyquinoline] (primaquine) and adamantanamine were selected. Primaquine was also incorporated into polyepichlorohydrin by nucleophilic substitution of the chlorine of the chloromethyl group by the primary aliphatic amino group of primaquine. The structure of the biuret polymers was established by elemental analysis, and by infrared 1H- and 13C-NMR spectroscopic characterization. Several attempts to use primaquine as a diamine for the formation of condensation polymers, including reaction of primaquine with sebacoyl chloride (to form polyamides), or with diisocyanates (to form polyureas) were unsuccessful.
    Additional Material: 9 Ill.
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  • 9
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: 2(2-Hydroxy-5-isopropenylphenyl)2H-benzotriazole was synthesized in 40% overall yield starting from o-nitroaniline. Diazotization in aqueous hydrochloric acid gave o-nitrophenyl diazonium chloride which was condensed with p-hydroxyacetophenone; the azo compound was reduced to 2(2-hydroxy-5-acetylphenyl) 2H-benzotriazole with zinc powder in sodium hydroxide solution and the 2-hydroxy group of the compound was acetylated. Treatment of the acetyl compound with methyl Grignard reagent resulted in the methylation of the 5-acetyl group to 2[2-acetoxy-5(2-hydroxy-2-propyl)phenyl]2H-benzotriazole which was then dehydrated with potassium hydrogen sulfate to the desired 2(2-hydroxy-5-isopropenylphenyl)2H-benzotriazole. This monomer did not homopolymerize, but was copolymerized readily with styrene, methyl methacrylate, and n-butyl acrylate with azobisisobutyronitrile as the initiator. 2(2-Acetoxy-5-acetylphenyl)2H-benzotriazole was also reduced with sodium borohydride to form 2[2-acetoxy-5-(1-hydroxyethyl)phenyl]2H-benzotriazole which was dehydrated and hydrolyzed to the known 2(2-hydroxy-5-vinylphenyl)-2H-benzotriazole. This route provides a novel and simpler synthesis of 2(2-hydroxy-5-vinylphenyl)2H-benzotriazole.
    Additional Material: 7 Ill.
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  • 10
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Maleic anhydride or 2,3-dimethylmaleic anhydride was copolymerized with a number of alkyl vinyl ethers, with AIBN as the initiator. The comonomers were always alternating and were obtained in yields ranging from 15 to 99%. The acid anhydride group in both series of copolymers was converted to the corresponding methyl esters in a two-step reaction. The structure of these polymers was established by elemental analysis and by infrared, 1H-and 13C-NMR spectroscopy. Addtional characterization of these copolymers were carried out by viscosity measurements, differential scanning calorimetry for the determination of glass transition temperatures, and thermal degradation for the determination of the thermal stability of the copolymers.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
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