Studies on mechanical and rheological properties of poly(vinyl chloride) modified with elastomers and rigid organic particles

Chlorinated polypropylene (CPP) as rigid organic particles and chlorinated polyethylene (CPE) as elastomer were used to modify the properties of poly(vinyl chloride) (PVC) by melt blending. Both mechanical and rheological properties of the PVC blends were investigated. The submicroscopic morphology of the blends was observed by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The results demonstrate that when the weight ratio of CPE to CPP is about 6: 1, a sample with the best impact strength and without obvious decline in tensile strength can be obtained. The impact strength correlates well with SEM morphologies, and TEM micrographs in the necking of the tensile specimen indicate that a cold-drawing deformation of rigid particles happens as reported by T. Kurauchi and T. Ohta (J Mater Sci 1984, 19, 1699). Therefore, a conclusion can be drawn that CPP particles acting similar to elastic particles can toughen PVC, and the cold-drawing deformation is the primary reason for toughening the PVC blends. In addition, the addition of CPP can promote the processibility of PVC ternary blends. (C) 2003 Wiley Periodicals, Inc.