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  • 1
    Electronic Resource
    Electronic Resource
    Springer
    Monatshefte für Chemie 121 (1990), S. 31-43 
    ISSN: 1434-4475
    Keywords: Fluorochlorobromoacetic acid ; 1,1,2-Trifluoro-2-chloroethylene, bromination ; 1,2-Difluoro-1-chloro-2-methoxyethylene
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung Fluorchlorbromessigsäure wurde aus 1,1,2-Trifluor-2-chlorethylen in vier Stufen mit einer Gesamtausbeute von ca. 25% hergestellt. 1,1,2-Trifluor-2-chlorethylen wurde zuerst mit Natriummethoxid zu 1,2-Difluor-1-chlor-2-methoxyethylen umgesetzt, das dann mit elementarem Brom bromiert wurde. Das Reaktionsprodukt daraus ergab nach Behandlung mit konzentrierter Schwefelsäure Methyl-fluorchlorbromacetat, das nach Hydrolyse mit verdünnter Natronlauge zur Zielverbindung führte.
    Notes: Abstract Fluorochlorobromoacetic acid was sythesized in the sequence of four steps from 1,1,2-trifluoro-2-chloroethylene in an overall yield of approximately 25%. 1,1,2-Trifluoro-2-chloroethylene was first allowed to react with sodium methoxide to form 1,2-difluoro-1-chloro-2-methoxyethylene, which was then brominated with elemental bromine and the reaction product treated with concentrated sulfuric acid to give methyl fluorochlorobromoacetate. This compound was hydrolized with a diluted sodium hydroxide solution to fluorochlorobromoacetic acid.
    Type of Medium: Electronic Resource
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  • 2
    Electronic Resource
    Electronic Resource
    Stamford, Conn. [u.a.] : Wiley-Blackwell
    Polymer Engineering and Science 23 (1983), S. 597-600 
    ISSN: 0032-3888
    Keywords: Chemistry ; Chemical Engineering
    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: Head-to-head polyisobutylene, prepared by the Grignard coupling reaction of 2,2,3,3-tetramethyl-1,4-dibromobutane had molecular weight of 3,000 to 10,000 and was characterized by wide angle x-ray diffraction, optical microscopy and thermal behavior. Head-to-head polyisobutylene is crystalline, with a crystalline melting point of 187°C and a glass transition temperature of 87°C (measured by DSC at a scan rate of 20°/min.); these values compare to a glass transition temperature of head-to-tail polyisobutylene of similar molecular weight of -61°C and a crystalline melting point of 5°C, which can only be observed when the sample was stretched. The maximum rate of degradation of head-to-head polyisobutylene (20°/min. programmed temperature increase) is at 315°C, 70°C lower than that of head-to-tail polyisobutylene.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
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  • 3
    ISSN: 0032-3888
    Keywords: Chemistry ; Chemical Engineering
    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: Homopolymers of 2,6-dimethylphenyl 10-undecenoate and copolymers of 2,6-dimethylphenyl 10-undecenoate with α-olefins, prepared by coordination initiators using aluminum activated titanium trichloride, and the corresponding sodium carboxylate and carboxylic acid derivatives have been characterized. IR and NMR investigations gave the normal; spectral characteristics typical for estersubstituted polyolefins and their derivatives. The thermal behavior of the polymeric esters, investigated by differential scanning calorimetry, showed glass transitions characteristic of poly(α-olefins). Polymeric acids and salts presented quite different behavior; most notably the polymeric salt showed no glass transition, but rather an exothermic transition, resembling a broad melting peak at 250-270°C, which is characteristic of a crystalline polymer. We interpret this behavior as the melting of carboxylate cluster domains, which according to our WAXD analysis has a domain size of about 25 Å.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
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