Mechanical and thermal properties of poly(ethylene terephthalate) fibers crosslinked with disulfonyl azides

Abstract

ABSTRACT:A novel method for the crosslinking of poly(ethylene terephthalate) fibers is described using 1,6-hexanedisulfonyl azide, 1,3-benzenedisulfonyl azide, and 2,6-naphthalenedisulfonyl azide. The azides are diffused into poly(ethylene terephthalate) fibers (Dacron) from perchloroethylene solution, and the fibers are heat treated to bring about decomposition of the sulfonyl azide and give rise to crosslinking. A study is made of the mechanical and thermal properties of the resultant fibers, which are changed considerably in comparison to the untreated fiber.

Thermomechanical and creep properties of poly(ethylene terephthalate) fibers crosslinked with disulfonyl azides

“…The crosslinked samples used in the experiments were those prepared previously,2 that is, samples that were treated at 140°C for 20 min to impregnate the fibers with azide and then at 200°C for 20 min to bring about crosslinking. The standard sample mentioned throughout the article was subjected to exactly the same treatment as the crosslinked samples, except that no azide was used so that no crosslinking would occur.…”

“…The standard sample mentioned throughout the article was subjected to exactly the same treatment as the crosslinked samples, except that no azide was used so that no crosslinking would occur. The PET used, as before,2 was obtained as a high‐end, partially oriented, continuous filament yarn in the form of grade 3 Dacron from DuPont (Pontypool, UK). This yarn consisted of 34 filaments with a circular cross section measuring a total of 167 dtex.…”

“…We recently described studies of the crosslinking of acrylic fibers1 and poly(ethylene terephthalate) (PET) fibers2 with disulfonyl azides. Although the acrylic fibers could be crosslinked sufficiently to maintain their fiber form in dimethylformamide, the partially oriented Dacron yarn always disintegrated in o ‐chlorophenol.…”

“…After this work,2 we considered it worthwhile to determine how the mechanical properties of the fibers varied under different conditions of temperature and loading because of crosslinking. It was thought that a thermomechanical examination of the crosslinked fibers in comparison with the blank‐treated standard fibers would yield valuable information concerning how the crosslinking affected the thermal extensibility of the fibers under increasing temperatures and under oscillating loads; the latter was thought to be informative of changes in the elastic modulus with respect to temperature due to the crosslinking.…”

Crosslinking of Semiaromatic Polyesters toward High‐Temperature Shape Memory Polymers with Full Recovery

“…In the past, PET was crosslinked for diverse purposes but not explored in terms of a shape memory . Chemical modification of PET at high temperatures is usually accompanied by degradation of the polymer .…”