The Toughening Investigation Of PVC Blending With Modified CPE And Blending Reaction With Nonelastomer

From two ways to toughen PVC, one is from elastomer blended toughening (CPE-cg-HEA and special CPE with special chlorine content and distribution). The other is from nonelastomer toughening, appling poly(vinyl chloride) -chlorinate,graft-malefic anhydride(PVC-cg-MAH) to toughen PVC. This article will investigate PVC toughening from the two ways.The toughness modifiers synthesized by in situ chlorinating graft copolymerization (ISCGC) are graft copolymers composed of poly (2-hydroxy ethyl acrylate) (PHEA) as branched chains and chlorinated polyethylene as backbone. Chlorinated polyethylene-chlorinate , graft-hydroxy ethyl acrylate(CPE-cg-HEA) presented a good effect for toughening of PVC. Especially when 5 phr CPE-cg-HEA was blended with PVC matrix, the tensile strength and notched impact strength respectively increased 17.9% and 30% than that of PVC/CPE blends. DSC analysis suggested the miscibility of PVC/CPE-cg-HEA was much better than that of PVC/CPE. The analysis of morphological structure showed that PHEA grafted onto chlorinated polyethylene(CPE) promoted amalgamation between the primary particles of PVC and the toughness modifiers. Further research of morphology and volume change experiment indicated that PHEA grafted onto CPE backbone made the toughening mechanism of PVC/CPE-cg-HEA system different form PVC/CPE system.Special chlorinated polyethylene(SCPE) was synthesized from high density polyethylene(HDPE)through solid phase method, in which a new kind CPE with special chlorine distribution was obtained by controlling the temperature and time of the chlorinating reaction. The synthesized special CPE can be used as a new modifier to toughen PVC. In this article, the mechanical property and microcosmic structure of the blended system was studied. The results showed that tensile strength of the blends increased 4% and notch impact strength of the blends increased 62.5% contrast to pure PVC. Results of DSC and 1H NMR indicated that chain segments of different chlorine content existed in molecular chains of special CPE. The special CPE blended with PVC can modify the toughness of PVC, and improve the tensile strength of blends at the same time. The analysis of morphological structure showed that the sufficient amalgamation between PVC phase and CPE phase was the reason to improve mechanical property of the blends.Poly(vinyl chloride) -chlorinate,graft- hydroxy ethyl acrylate (PVC-cg-HEA) and poly(vinyl chloride) -chlorinate , graft-malefic anhydride(PVC-cg-MAH) synthesized by in situ chlorinating graft copolymerization (ISCGC) can be blended, in which PVC-cg-HEA was continuous phase and PVC-cg-MAH was dispersion phase with non-elastic toughness. And two copolymers have reactive structure, by which a new modification material of PVC can be gained through reactive blending at appropriate temperature. On one hand, a new material with a good tensile strength can be obtained by the nonelastomer PVC-cg-MAH added into this blend. On the other hand, the flexibility of the new material can be enhanced by the reaction of two copolymers increasing molecular weight of PVC. Both the tensile strength and impact strength can be improved, and the ideal modification of PVC can be achieved.