STUDIES ON STRUCTURAL-CHANGES IN AND DAMAGE TO POLYESTER-FIBER CONTINUOUS-FILAMENT YARN DURING SIZING

This paper presents an account of mechanical, thermal, and thermomecha nical damage taking place during the sizing of polyester-fibre continu ous-filament yarns. Structural changes due to axial, transverse, and t angential forces on the yarn during sizing are studied by using X-ray- diffraction and birefringence techniques; Surface damage to the yarn i s examined by the scanning electron microscope. The effect of a squeez e load on fibre damage is also investigated. The study is extended to textured and microdenier multifilament yarns.