Study On Copolymers Of Vinyl Chloride-vinyl Acetate

In this paper, Copolymers of vinyl chloride (VC) with vinyl acetate (VAc) are obtained by free radical polymerization in suspension system. But VAc contents of copolymers are different. The resin that had 4-15% VAc was made through alarge number of experment. Different VAc content for copolymers have utility in a broad range of large volume applications. This study is focused on influentied the factor of the polymerizing conditions on copolymerization, such as reaction temperature, suspending agents, VC-VAc ratio, oil/water ratio, etc. Molecular weight of VC-VAc resin was characterized by using viscosity. Absolute viscosity of these copolymers were obtained in 1.54-1.65x10-3 pa-s at 25C. Different viscosity shows different molecular weight.The results of this study show that physical and chemical index of resin be content with th demands of the factory standard. It are listed 1.2. The product of the reaction confirm that the infrared spectrgram(1R) is VC-VAc copolymers. The analysis of SEM indicates that the copolymer particles of VC-VAc suspension were spherical such as cotton ball. In addition, heat stability of VC-VAc resin were also investigated by make use of HAAKE torque rheometer at 180C. Expermental results show that heat stability of VC-VAc copolymer was poor. Because of the limited heat stability, it must add to heat stability when resin process at the higher temperatures.