STUDIES OF RIGID POLY(VINYL CHLORIDE) (PVC) COMPOUNDS .4. FUSION CHARACTERISTICS AND MORPHOLOGY ANALYSES

Poly(vinyl chloride) (PVC), PVC/chlorinated polyethylene (CPE), PVC/ox idized polyethylene (OPE), and PVC/CPE/OPE compounds were prepared in a Haake torque rheometer at various temperatures, rotor speeds, and to talized torques (TTQ). The fusion characteristics of these PVC compoun ds (fusion time, fusion torque, and fusion temperature) were studied. Longer fusion time results in higher fusion temperature. Higher fusion temperature results in lower fusion torque. The fusion time of PVC/OP E compounds is the longest among these PVC blends. However, the fusion time of PVC/CPE/OPE compounds is the shortest among these PVC blends. The fusion time of the PVC/CPE/OPE compound is significantly differen t from those of PVC, PVC/OPE, and PVC/CPE compounds at the medium star ting temperature and the medium rotor speed. Scanning electron microsc opy (SEM) analyses successfully revealed the surface morphological cha nges of the fusion of PVC, PVC/OPE, PVC/CPE, and PVC/CPE/OPE compounds . The lubrication mechanisms of these PVC compounds have also been pos tulated. (C) 1995 John Wiley & Sons, Inc.