Polyester Fiber and Microfiber Structure by X-Rays and Viscoelasticimetry

Abstract

We have studied three polyethylene terephthalate filaments from the same manufac turer. The results of the dyeing process depend on the filament characteristics. Dyeing modifies the macromolecular organization according to the manufacturing process. To understand the dyeing influence, each filament undergoes heat treatments that reproduce the effect of dyeing. Organizational molecular modifications are determined by x-ray diffraction measurements and by a viscoelasticimeter. The study shows that drawing and shearing align macromolecules that act on the crystallinity. Thus, the crystallinity of a trilobal filament and a microfilament are almost identical, whatever the heat treatment. The less significant drawing of a circular filament provides more amorphous and more sensitive filaments for heat treatment. Super-drawing induces the existence of macromo lecular segments of great mobility. Moreover, organizational heterogeneity is detected at the time of the glass transition.