Structural Properties Of PVC Copolymer Resin And Film Processing Research

Due to the presence of polar group and strong intermolecular force, PVC have poor impact resistance and poor processing, which limits the range of application. In this paper, we get the Vc-VAC copolymer by used the suspension polymerization method for modification of polyvinyl chloride. Then the processing technology was studied and prepared non-toxic, soft film products.After the analysis of NMR and Fourier transform infrared spectroscopy to the resin particles, the result show that the material after polymerization is the copolymers of two monomers. The DSC analysis show that the glass transition temperature gradually reduced with the increase of VAc content, substantially in line with the calculated values of Fox equation.Because of the vinyl acetate monomer, the interfacial tension of the monomer mixture with water becomes large, the dispersion capability becomes weak, so the average particle diameter of the resin is large.With the increases of the vinyl acetate content, the viscosity index and plasticizer absorption of the resin decreases. Through the discovery of scanning electron microscopy of the resin, compared with pure PVC, the copolymer resin particle size is large than PVC resin and the resin surface has many fold. The looseness of the resin is decreased.When heated, vinyl chloride-vinyl acetate copolymer resin has poor stability and easily decomposed, heat stabilizers must be added in the processing. Through the study found that the stabilizing effect of heat stabilizers for the vinyl chloride-vinyl acetate copolymer resin are: organotin stabilizer>rare earth stabilizer>Ca-Zn composite stabilizer.By the study of Vc-VAc copolymer processing found that, due to the presence of vinyl acetate, the copolymer resin can not use the two-roll molding. With the increase of VAc content, the compounding temperature and the melting temperature decrease. The studies of its mechanical properties show that the vinyl acetate segment has good plasticized and toughening effect.Compared with DOP, Tributyl Citrate(TBC) have a good compatibility with the copolymer resin. Environmentally friendly, non-toxic, transparent and flexible film products were prepared by use the TBC.