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  • Physics  (4)
  • PK99  (1)
  • 1
    Electronic Resource
    Electronic Resource
    Springer
    Journal of thermal analysis and calorimetry 61 (2000), S. 565-578 
    ISSN: 1572-8943
    Keywords: crystallization ; DSC ; PK99 ; rigid amorphous fraction ; WAXD
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract An analysis of the crystallization behaviour of a new poly(aryl-ether-ether-ketone-ketone), PK99, by differential scanning calorimetry (DSC) and wide-angle X-ray diffraction (WAXD) is presented. Isothermal crystallization TG were obtained in the whole range between the glass transition temperature (T g) and the melting temperature (T m) as a consequence of the slow crystallization kinetics stemming from the closeness of these transitions. The calorimetric results, compared with WAXD data, were applied to determine the theoretical melting temperature and crystallization enthalpy. The DSC and WAXD data were combined in order to calculate the total amount of the crystallizable fraction of the polymer, and a model was proposed to explain the difference between the fractions of crystallinity observed with these techniques. The thermal and X-ray data were also correlated with different lamellar morphologies arising from the crystallization conditions. Finally, DSC experiments on the crystallized sample were used to detect the presence of a rigid amorphous phase which does not relax at T g.
    Type of Medium: Electronic Resource
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  • 2
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 2661-2666 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: ESCA has been used to investigate the composition and structural features of plasma-polymerized 2,4,6-trifluoro-1,3,5-triazine. Polymer formation was studied as a function of power and post-polymerisation treatment. All the polymer films revealed an intense peak at a binding energy of ∼290.2 eV probably arising from groups. A high sensitivity towards hydrolysis was observed resulting in substantial loss of fluorine and increase in oxygen content of the plasma polymers.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
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  • 3
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 15 (1977), S. 5-13 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The synthesis of a series of polyamides and copolyamides containing α-truxillic and adipic units in the chain is reported. The thermal degradation of these polymers was investigated by direct pyrolysis in the ion source of a mass spectrometer. Thermal degradation reactions were followed directly by this method by detecting the thermal- and electron-impact-induced fragments. The results obtained show a good correlation between the intensity of mass peaks characteristic of truxillic and adipic moieties and the composition of the copolyamides, as ascertained by elemental analysis. This is an important result since it shows the potential of the direct pyrolysis method in the analysis of copolymers. Relevant information on the relative thermal stabilities of the polymers investigated has been also obtained.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
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  • 4
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 17 (1979), S. 1463-1471 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The synthesis of copolyamides from adipic and truxillic acids with piperazine was undertaken to include photoreactive units in aliphatic polyamides and to throw light on the factors that control the photolytic rates and photochromic behavior of these materials. The results indicate that the introduction of variable amounts of truxillic units (photodegradable) induces a measurable increment in the photolytic rate of the aliphatic polyamide. Moreover, it has been found that the addition of strong acids induces a higher photolytic cleavage of the polyamides, which may allow a further reduction in the amount of truxillic units in the copolyamides.
    Additional Material: 7 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 16 (1978), S. 3123-3130 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The effect of strong acids on the photolysis of stereoisomeric polyamides containing photoreactive cyclobutane units was studied, and a drastic increase in the photolytic rates was observed. Protonation of amide groups can explain the mechanism of this catalytic effect, being the photolytic rates affected not only by the steric congestion around the cyclobutane ring but also by the basicity of the amide group as a function of the substituent. Molecular weight decrease of the irradiated polymers was monitored by viscosity measurements, and it was found sensibly affected by the presence of small amounts of strong acids.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
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