Study On Structure And Properties Of PVC Copolymer Resin And Film Processing

Due to the polar group, the force between molecular chains begans strong, as a result, its impact resistance and processing properties are poor, which limit the range of application. In this paper, we studied on the copolymerization modification of polyvinyl chloride by the suspension polymerization method. We got the VC-VAc-BA copolymer, studied their structure and properties and processing technology and prepared non-toxic, soft flim products. The main work is as follows:Prepared the VC-VAc-BA copolymer by suspension polymerization method, analized the NMR and Fourier transform infrared spectroscopy to the resin particles. The result showed that the material we got was the copolymer of the three monomers. The molecular weight distribution of the VC-VAc-BA copolymer was wide. When the feed mass fraction of VC was 70%, with the increase of the mass fraction of BA, the viscosity of the resin decreased, the average particle size increased, the amount of plasticizer absorption reduced. Through the discovery of SEM of the resin, there were many fold on the surface.Through the analysis of DSC, the Tg of the resin reduced with the increase of BA mass fraction.Through the processing of the VC-VAc-BA copolymer film, we found that the resin couldn’t be processed by the double roller mixing plasticization and molding because of the ester. We used single screw to extrude, three rolling machine to calend and mold. When the feed mass fraction of VC was 70%, with the increase of the mass fraction of BA, the pre-mixing temperature and screw melting temperature of the copolymer resin decreased. The processing performance of the resin was improved because of the BA monomer. The analysis of the mechanical properties showed that BA had a good effect on internal plasticization. This can reduce the use amount of plasticizer.The segment of BA is very soft. Through the study of mechanical properties of the PVC after processing, we found that VC-VAc-BA copolymer resin could be used as anti impact modifier for PVC.