Abstract
The thermal shrinkage of fibrous homopolymers and copolymers by the partial melting of crystalline regions may be understood theoretically on the basis of the theories on melting in homo- and copolymers as described in our preceding papers.
The purpose of this work is to investigate the thermal shrinkage of fibrous substantial copolymers by appling the relation between the relative shrinkage and the absolute temperature derived from the theories on melting in copolymers composed of units of type A capable of crystallizing and other units B incapable of crystallizing proposed in our preceding papers.
It may be assumed that the thermal shrinkage curves of fibrous copolymers show some features differing from the shrinkage curves of fibrous homopolymers because the dependence of the crystallinity to temperature is characteristic for copolymers especially.
The fibrous samples used are polyethylene terephthalate/isophthalate copolymer fibers, with which the thermal shrinkage curves were discussed from a stand point as mentioned above in comparison with the results of DTA.
