MODIFICATION OF POLY(STYRENE-CO-ACRYLONITRILE) (SAN) WITH CHLORINATEDPOLYETHYLENE (CPE)

Melt blends of poly(styrene-co-aclylonitrile) (SAN) with chlorinated p olyethylene (CPE) were prepared in a twin-screw compounding machine. T he morphological textures of the blends were determined by scanning el ectron microscopy (SEM). The mechanical properties were obtained from Instron, and the rheological properties from Rheometric Dynamic Spectr ometer. SEM micrographs showed that the blend is incompatible. The imm iscibility was confirmed by dynamic mechanical analysis. Addition of C PE to SAN did not cause a significant increase in impact strength or e longation at break. The tensile strength decreased almost linearly wit h increasing amounts of CPE. The plastic-to-rubber percolation thresho ld was about 70 vol% CPE.