MISCIBILITY, PHASE-BEHAVIOR, AND MECHANICAL-PROPERTIES OF TERNARY BLENDS OF POLY(VINYL CHLORIDE) POLYSTYRENE/CHLORINATED POLYETHYLENE-GRAFT-POLYSTYRENE/

The effectiveness of chlorinated polyethylene-graft-polystyrene (CPE-g -PS) as a polymeric compatibilizer for immiscible poly(vinyl chloride) /polystyrene (PVC/PS) blends was investigated. The miscibility, phase behavior, and mechanical properties were studied using differential sc anning calorimetry (DSC), dynamic mechanical analysis (DMA), Izod impa ct tests, tensile tests, and scanning electron microscopy (SEM). DSC a nd DMA studies showed that PVC is immiscible with chlorinated polyethy lene (CPE) in CPE-g-PS, whereas the PS homopolymer is miscible with PS in CPE-g-PS. The PVC/PS/CPE-g-PS ternary blends exhibit a three-phase structure: PVC phase, CPE phase, and PS phase that consisted of a PS homopolymer and PS in CPE-g-PS. The mechanical properties showed that CPE-g-PS interacts well with both PVC and PS and can be used as a poly meric compatibilizer for PVC/PS blends. CPE-g-PS can also be used as a n impact modifier for both PVC and PS. SEM observations confirmed, aft er the addition of CPE-g-PS, improvement of the interfacial adhesion b etween the phases of the PVC/PS blends. (C) 1998 John Wiley & Sons, In c J Appl Polym Sci 69: 995-1003, 1998.