原位聚合法制备PVC/地聚物复合材料

Preparation of PVC/Metakaolin Based Geopolymer Composites via In-Situ Suspension Polymerization

通过偶联改性偏高岭土基地聚物存在下的氯乙烯原位悬浮聚合制备聚氯乙烯(PVC)/地聚物复合树脂,研究了地聚物加入方式与用量、复合分散剂组成对复合树脂颗粒特性和理化性质的影响,同时分析了PVC/地聚物复合材料的力学和热性能。结果表明,地聚物添加量质量分数不大于4%时,采用倒加料聚合工艺和聚乙烯醇/羟丙基甲基纤维复合分散体系,可聚合得到粒径分布较窄、理化指标符合国标要求的PVC复合树脂。随着地聚物添加量的增大,PVC/地聚物复合材料的抗冲击强度、拉伸强度和断裂伸长率先增大后减小。与未添加地聚物的PVC材料相比,地聚物质量分数为3%的PVC复合材料的抗冲击强度和拉伸强度分别提高56%和14%。地聚物对PVC热分解脱除HCl过程有抑制作用,能提高PVC的分解温度,同时地聚物的加入可提高PVC耐热形变温度。

Poly vinyl chloride （PVC）/geopolymer composite resins were prepared through in-situ suspension polymerization of vinyl chloride in the presence of organic modified metakaolin based geopolymer. The effects of the way of feeding, amount of geopolymer, and composition of dispersants on the particle features and physical properties of PVC/geopolymer composite resins were investigated. The mechanical and thermal properties of PVC/geopolymer composites were also studied. The results show that the optimal geopolymer addition is 3% in the PVC/geopolymer composite resin. By inversely feeding and polyvinyl alcohol/hydroxypropyl methylcellulose fiber as composite dispersion, the obtained PVC/geopolymer composite resin has a narrow particle size distribution and physical properties meeting GB standards. As the addition of geopolymer increases, the impact strength, tensile strength and elongation-at-break of PVC composites first increase and then decrease. A 3% geopolymer additive enhances the impact and tensile strengths of PVC composites by 56% and 14%, respectively. The addition of geopolymer also improves the thermal stability of PVC since geopolymer can inhibit the HC1 release in PVC thermal degradation. Furthermore, the heat deformation temperature of PVC composites is increased with the addition of geopolymer, too.