Thermal analysis in the investigation of composite polymers

Abstract

The methods of thermal analysis are successfully used for identification of the processes of formation, degradation and strueturization of composite polymers. On the examples of the investigation of the thermoehemical reactions of polyamic acids with polystyrene, polyvinylpyrolidone, polyaerylonitrile, polyvinyltetrazole and epoxy and furol resins, the high yield of information by the methods of thermal analysis in the investigation of these polymers is demonstrated.At present, there is considerable interest in the problem of the compatibility of various polymers. For the solution of practical problems, it is necessary in many cases to prepare materials whose properties cannot be ensured by one polymer alone. This is particularly so for block and graft copolymers, in the synthesis of which it is possible to combine some opposite characteristics of the initial polymers, e.g. hydrophobicity and hydrophilicity, strength and flexibility, thermoplastic and thermosetting properties, etc. Besides copolymer materials in which elementary fragments or blocks of initial homopolymers are bonded to each other by chemical bonds, there are also composite material in which the homopolymers are joined according to other principles. The deciphering of the mechanism for the formation of composites, and the search for the relationships responsible for the appearance of new qualities of composites differing from those of the initial polymers, is an interesting and feasible problem of thermal analysis. It should be noted that in many cases the formation of composite polymers proceeds at high temperatures, which makes it possible to apply widely all methods of thermal analysis, both in the stage of formation of the John Wiley & Sons, Limited, Chichester Akad~rniai Kiadb, Budapest