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  • 1
    ISSN: 1434-4475
    Keywords: Benzotriazole formation ; N M R-structure analysis ; Polymerization and copolymerization ; Ultraviolet absorbers ; 2[2-Vinyl-4-hydroxyphenyl]2H-benzotriazole ; 2[3-Vinyl-4-hydroxyphenyl]2H-benzotriazole
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung Diazotierteso-Nitroanilin wurde mit 3-Ethylphenol bzw. mit 2-Ethylphenol kondensiert. Reduktion der Diazoverbindung mit Zinkstaub in Natriumhydroxid ergab 2-(2-Ethyl-4-hydroylphenyl)2H-benzotriazol, bzw. 2-(3-Ethyl-4-hydroxyphenyl)2H-benzotriazol. Nach Acetylierung der freien Phenolgruppe wurden diese Verbindungen mitN-Bromsuccinimid zu den entsprechenden1-Bromethylverbindungen umgewandelt und daraufhin in Acetonitril mit Triethylamin dehydrobromiert. Darauf folgende Hydrolyse führte zu 2(2-Vinyl-4-hydroxyphenyl)2H-benzotriazol bzw. zu 2(3-Vinyl-4-hydroxyphenyl)2H-benzotriazol. Beide monomeren Verbindungen wurden sowohl homopolymerisiert als auch mit Styrol oder mit Methylmethacrylat copolymerisiert. Weder die Ethyl- noch die Vinylverbindungen oder deren Polymere erwiesen sich als UV-Stabilisatoren, eine Eigenschaft die den 2(2-Hydroxyphenyl)2H-Benzotriazolen eigen ist. Eine Methode der Strukturbestimmung mit Hilfe einer detaillierten NMR-Analyse wird ebenfalls beschrieben.
    Notes: Abstract Condensation of diazotizedo-nitroaniline with 3-ethylphenol or with 2-ethylphenol followed by reduction of the resulting azo compound with zinc dust in sodium hydroxide solution gave 2-(2-ethyl-4-hydroxyphenyl)2H-benzotriazole and 2(3-ethyl-4-hydroxyphenyl)2H-benzotriazole, respectively. The individual compounds were acetylated, brominated withN-bromosuccinimide to the corresponding 1-bromoethyl compounds which were then dehydrobrominated with triethyl amine in acetonitrile and hydrolyzed to 2(2-vinyl-4-hydroxyphenyl)2H-benzotriazole or 2(3-vinyl-4-hydroxyphenyl)2H-benzotriazole. The two monomers could be polymerized and copolymerized with styrene and methyl methacrylate. The ethyl as well as the vinyl compounds and the corresponding polymers, when tested, are ineffective as ultraviolet absorbers as they have structures of 4-hydroxyphenyl rather than 2-hydroxyphenyl compounds with respect to the benzotriazole ring. A careful NMR analysis for the correct structural assignment is also described.
    Type of Medium: Electronic Resource
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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. 2059-2074 
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Acryloyl-type polymer fixing 1-β-carbonylethyl-5-fluorouracil residues through D-glucofuranoses via ester bonds was synthesized by means of polymerization of the corresponding monomer and polymer reaction. In order to provide the water-soluble objective polymer, the copolymerization of the acryloyl-type monomer with acrylamide was carried out. The extent of release of 5-FU residues from the copolymer was investigated in the enzyme or nonenzyme system in vitro. Furthermore, the antitumor activities of the water-insoluble homopolymer and water-soluble copolymer obtained were tested in vivo.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
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  • 3
    Electronic Resource
    Electronic Resource
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 26 (1988), S. 657-675 
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A number of derivatives of ω-alkenoates were synthesized in preparation for the synthesis of functional polymers based on α-olefins. For the preparation of most of the methyl esters, the regular esterification of ω-alkenoic acids, specifically 10-undecenoic acid with methanol and sulfuric acid as the catalyst, was most effective. For the preparation of the tert-butyl- and 2-ethylhexyl esters of 10-undecenoic acid, the acid chloride route was found to be most convenient, whereas for the preparation of the corresponding esters of 5-hexenoic acid, our method of choice was the synthesis via the imidazolyl derivative of the acid. 2,2,2-Trifluoroethyl 10-undecenoate and the 2,2-dimethyloxazolidine derivative of 10-undecenoic acid were prepared from the acid and 2,2,2-trifluoroethanol or 2-amino-2-methyl-propanol with p-toluene sulfonic acid as the catalyst. Esters of phenol, 2,6-dimethylphenol, and 2,6-diphenylphenol were synthesized from 3-butenoic and 10-undecenoic acid with trifluoroacetic anhydride.
    Additional Material: 2 Ill.
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  • 4
    Electronic Resource
    Electronic Resource
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 24 (1986), S. 2327-2349 
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Polymerization of linear methyl ω-epoxyalkanoates of C-3 to C-10 carboxylic acids (0 to 7 methylene groups between oxirane ring and carbomethoxy group) was accomplished with a triethylaluminum/water/acetylacetone (1.0/0.5/1.0) initiator system to yield polymers of high molecular weight, apparently via a coordinative anionic mechanism. The rate of polymerization increased as the number of methylene groups between the oxirane ring and the carbomethoxy group increased, up to three methylene groups. When more than three methylene groups separate the polymerizable oxirane group and the carbomethoxy group, the rate of polymerization becomes essentially constant. The polymers were characterized by their infrared and 13C-NMR spectra, DSC, GPC, and inherent viscosity. The lower members of the series (ω-epoxyalkanoates of n 〈 3) gave polymers of lower molecular weight and wider-molecular-weight distribution (Mw/Mn 〉 2), while the higher members had molecular weight distributions between 1.5 and 2. The glass transition temperatures of the polymers also decreased from -26°C for n = 1 to around -50 to -55°C for n ≥ 3.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
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  • 5
    Electronic Resource
    Electronic Resource
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 26 (1988), S. 677-700 
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Esters of ω-alkenoic acids have been homopolymerized with transition metal initiating systems. The key to the successful polymerization was the complexation of the monomer prior to its addition to the initiating system. Titanium trichloride, aluminum activated, was found to be best as the transition metal part of the initiator systems, with diethyl-, or better, diisobutylaluminum chloride as the reducing agents and n-hexane or toluene as the solvents. Best results for polymerizations were obtained with 2,6-dimethylphenyl esters of the functional α-olefin monomers; however, other phenyl esters also polymerized well. Attempts to polymerize methyl 10-undecenoate gave the corresponding polymer in only low yields. Polymers of the 2,6-dimethylphenyl esters, obtained in high molecular weight, were characterized. Polymers were also obtained from 2,6-dimethylphenyl 7-octenoate, but not from ω-alkenoates with less than three methylene units between the ester group and the terminal olefin group.Poly(2,6-dimethylphenyl 10-undecenoate) was hydrolyzed in an aqueous sodium hydroxide/1,4-dioxane solution to poly(sodium 10-undecenoate) that in turn was neutralized with acetic acid to poly(10-undecenoic acid).
    Additional Material: 3 Ill.
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  • 6
    Electronic Resource
    Electronic Resource
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 27 (1989), S. 2051-2063 
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The 2,6-dimethylphenyl ester of 10-undecenoic acid was copolymerized with 1-dodecene, 1-octene, 1-hexene, propylene, and ethylene using coordination initiation systems based on “aluminum-activated” titanium trichloride and dialkylaluminum chlorides. The copolymerizations with higher α-olefins proceeded smoothly and gave copolymers incorporating from 60 to 90% of the 10-undecenoate feed. Copolymerization with propylene gave incorporation of 5 mol % of 2,6-dimethylphenyl 10-undecenoate; with ethylene only 3 mol % of the ω-alkenoate was readily incorporated. All copolymers were characterized by elemental analysis, dilute solution viscosity, and by their IR 1H- and 13C-NMR spectra.
    Additional Material: 1 Ill.
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  • 7
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Letters Edition 25 (1987), S. 279-285 
    ISSN: 0887-6258
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
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  • 8
    Electronic Resource
    Electronic Resource
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 1855-1860 
    ISSN: 0887-624X
    Keywords: helical conformation ; stereospecific polymerization ; isotactic ; polyacetaldehyde ; polytrifluoroacetaldehyde (polyfluoral), polytrichloro-acetaldehyde (polychloral) ; polytribromoacetaldehyde (polybromal) ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Minimum potential energy helical conformations for a family of four isotactic polyacetaldehydes have been determined. Our results indicate that all of the polymers form irrational helices. Comparisons have been made with the reported structures for two of these stereoregular polymers based on earlier X-ray diffraction data. c-Axis values associated with the pitch of the helix for polyacetaldehyde and for polytrichloroacetaldehyde (polychloral) were experimentally measured to be 0.48 and 0.51 nm, respectively. Our calculated conformations afforded values for a helix pitch of 0.47 and 0.52 nm, respectively, which derive from a 3.9/1 helix for polyacetaldehyde and a 3.7/1 helix for polychloral. The structure for polytribromoacetaldehyde (polybromal) was predicted to be similar to that for polychloral. For polytrifluoroacetaldehyde (polyfluoral) and polyacetaldehyde, a number of helical conformations with similar energies were found. All of these conformations could be related to the polychloral helical structure. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 1855-1860, 1998
    Additional Material: 4 Ill.
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  • 9
    ISSN: 0959-8103
    Keywords: optical activity ; solid-state measurements ; natural polymers ; suspension ; birefringence ; isorefractive media ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: The optical activity of ten natural-type polymers [poly(α-aminoacids), polysaccharides, proteins and nucleic acids] was measured in solution, as solid powders in suspension, and where possible in the form of films. In some cases the specific rotation of powder samples showed significant differences to the values obtained from solution measurements. The discrepances seem to reflect the arrangements of polymer chains in supermolecular assemblies in the polymer solid state.
    Additional Material: 11 Ill.
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  • 10
    ISSN: 0959-8103
    Keywords: optical activity ; polylactides ; poly(β-hydroxybutyrates) ; solid state measurements ; circular dichroism ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: The optical activities of poly-(R)-lactide, poly-(S)-lactide, poly(β-hydroxybutyrate) and two β-hydroxyvalerate copolymers were measured in solution, as solid powders in suspension, and where possible, as films. Poly-(+)-3-methyl-1-pentene was also reinvestigated. In some cases the specific rotation values of powder samples showed significant differences from the values of the solution measurements. The discrepancies of the data observed seem to reflect the local environment of the polymer chains in supermolecular assemblies and consequently the solid state structure(morphology)of the polymers.The circular dichroism (CD) spectra of the polymers were also measured in solution and in the form of their films. For comparison, the CD spectra of the naturally occurring protein casein and of the synthetic polypeptide poly-(L)-proline were also measured.
    Additional Material: 13 Ill.
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