Poly(ethylene terephthalate) fibres with improved mechanical properties

Abstract

Abstract Cold drawn poly(ethylene terephthalate) (PETP) fibres are subjected to zone annealing or isothermal annealing with fixed ends. The morphological changes taking place during both types of thermal treatment are followed by means of SAXS, WAXS, birefringence and density measurements, DSC, and mechanical tests. Differences in the supermolecular structure of the samples subjected to zone annealing and those annealed with fixed ends are established. Zone annealing results in better definition of the basic structural elements, higher orientation and larger number of taut tie molecules which in turn predetermine the higher performance of the zone annealed material.