ISSN:
0360-6376
Schlagwort(e):
Physics
;
Polymer and Materials Science
Quelle:
Wiley InterScience Backfile Collection 1832-2000
Thema:
Chemie und Pharmazie
Notizen:
A series of polyaryloxyphosphazene copolymers with the general formulas [NP(OC6H5)(OR)]n and [NP(OC6H4-4-OCH3)(OR)]n, where R = C6H4-4-CH3, C6H4-4-C2H5, C6H4-4-isoC3H7, C6H4-4-sec-C4H9, C6H4-4-tert-C4H9, C6H4-4-OCH3 or C6H4-4-OC4H9, have been prepared under anhydrous conditions. Copolymers as well as selected homopolymers were prepared by the reaction of polydichlorophosphazene with appropriate sodium aryloxides. Each of the polymers was characterized by elemental analysis, infrared spectroscopy, gel-permeation chromatography, and differential scanning calorimetry. Elemental analysis established the empirical formula for the polymers and showed that there were no residual P—Cl bonds left on the polymer backbone. Infrared spectroscopy indicated the presence of a phosphorus-nitrogen backbone with two aryloxy groups bonded to each phosphorus atom. The copolymers examined exhibited molecular weights of above 1 × 106. Polyaryloxyphosphazene copolymers were examined by differential scanning calorimetry and compared to several of the corresponding homopolymers. Glass transition temperatures ranged between -34 and +44°C for the polymers. The Kelley-Bueche equation was used to predict the glass transition temperatures of the copolymers. Close agreement was found between calculated and experimental values for most of the systems examined.
Zusätzliches Material:
4 Tab.
Materialart:
Digitale Medien
URL:
http://dx.doi.org/10.1002/pol.1977.170150210
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