聚丙烯酸丁酯接枝共聚物的可控合成及作为相容剂的应用

Synthesis of Poly(butyl acrylate) Graft Copolymers and Their Application as Compatibilizer in SAN/ACM Blend System

结合电子转移再生催化剂原子转移自由基聚合(ARGET ATRP)和普通自由基聚合,制备了一系列聚丙烯酸丁酯接枝共聚物,详细研究了其作为苯乙烯-丙烯腈共聚物树脂/丙烯酸酯橡胶(SAN/ACM)共混体系的相容剂,在制备丙烯腈-苯乙烯-丙烯酸酯树脂(ASA树脂)时,不同主链结构、侧链相对分子质量、接枝密度及用量对增容效果的影响。通过傅里叶变换红外光谱仪和凝胶渗透色谱仪对聚合物结构进行测试和表征;采用动态力学分析仪(DMA)和冲击试验机研究了共混物的力学性能。结果表明,成功制备了不同结构的聚丙烯酸丁酯接枝共聚物,以苯乙烯-丙烯腈共聚物(SAN)作为主链比聚丙烯酸丁酯(PBA)作为主链的接枝共聚物具有更好的增容效果。此外,侧链PBA的相对分子质量较小时,侧链与主链摩尔比为3∶1及相容剂用量为3%(质量分数)时,接枝共聚物的增容效果最佳。DMA分析表明添加接枝共聚物后SAN和ACM两组分的玻璃化转变温度相互靠近,聚丙烯酸丁酯接枝共聚物起到了明显的增容作用。

A series of poly （butyl acrylate） graft copolymers were synthesized via atom transfer radical polymerization with activators regenerated by electron transfer （ARGET ATRP） and conventional radical polymerization. The graft copolymers were utilized as compatibilizer in the blends of styrene-acrylonitrile copolymer resin and acrylate rubber system（SAN/ACM）. Effects of the structure of main chain, the molecular weight of the side chain, the graft density, and the amount of graft copolymer on the performance of ASA resins were investigated in detail. The graft copolymers obtained were characterized by GPC and FT-IR. The mechanical performances were investigated by impact testing machine and DMA. The results show that poly （butyl acrylate） graft copolymers are successfully synthesized. In the blends of SAN/ACM, graft copolymer with SAN as main chain shows better compatibilization than that with PBA as main chain. When the molecular weight of the side chain is small, SAN-g-PBA performs better. The impact strength of blends with poly （butyl acrylate） graft copolymer reaches the maximum value as the graft density of the graft copolymer is 3. When the amount of compatibilizer used is 3% of the total mass, the impact strength reaches 6.06 kJ/m2. DMA shows that the glass transition temperature of SAN and ACM comes closer to each other after the addition of graft copolymer, which indicates that poly （butyl acrylate） graft copolymer plays a role of compatibilizer.