RAFT乳液聚合法合成线形三嵌段丙烯酸酯共聚物及其在PVC中的应用

Synthesis of Linear Triblock Poly(co-acrylates) via RAFT Emulsion Polymerization and Its Application in PVC

采用可逆加成-断裂转移(RAFT)乳液聚合法合成了相对分子质量分布指数为1.8的甲基丙烯酸甲酯-丙烯酸丁酯-甲基丙烯酸甲酯(MMA-b-BA-b-MMA,MBM)三嵌段共聚物并将其与聚氯乙烯(PVC)进行共混。利用转矩流变仪测试了共混物的塑化行为;用动态热力学分析仪(DMA)测试了共混物的动态力学行为并测试了共混物的力学性能。结果表明,MBM的加入可以有效减小PVC的塑化时间和平衡扭矩;共混物储能模量(E′)随MBM含量的增加而减小;当MBM含量为25%(质量分数,下同)时,共混物的玻璃化转变温度(Tg)为71.9℃,比纯PVC提高了5.2℃;冲击强度为9.00kJ/m2,是纯PVC的4.0倍,拉伸强度为35.79 MPa。

A triblock copolymer,methyl methacrylate-b-butyl acrylate-b-methyl methacrylate(MBM),was synthesized via reversible addition-fragmentation chain transfer(RAFT)emulsion polymerization and was blended with poly(vinyl chloride)(PVC).The plasticizing behavior and dynamic mechanical properties were studied using torque rheometer and dynamic mechanical analyzer,and the mechanical properties were tested.It showed that MBM could efficiently reduce plasticizing time and balance torque;the storage modulus E′ of the blends decreased with increasing MBM content.When the MBM content was 25wt%,the glass transition temperature of the blends was 71.9 ℃,5.2 ℃ higher than neat PVC.The impact strength was 9.00kJ/m2,4.0times higher than neat PVC.The tensile strength was 35.79 MPa.