用氯化钠-无水三氯化铝协同增容聚苯乙烯/三元乙丙橡胶共混物

Synergistic compatibilization of polystyrene/ethylene-propylene-diene monomer blends by sodium chloride and anhydrous aluminium chloride

在熔融状态下利用Friedel-Crafts烷基化反应原位增容聚苯乙烯(PS)/三元乙丙橡胶(EPDM)共混物,研究了不同的催化体系对PS/EPDM共混物性能及动态流变行为的影响。结果表明,加入助催化剂氯化钠的催化体系有利于强化PS与EPDM间的接枝反应,同时降低EPDM的交联反应,提高了PS/EPDM共混物的力学性能;动态力学分析结果表明加入助催化剂后PS/EPDM共混物的储能模量和PS的玻璃化转变温度均降低;动态流变行为显示,在低频率区域,加入了助催化剂的共混物其动态储能模量、损耗模量和复数黏度均高于加入普通催化体系者,损耗因子低于普通催化体系;从扫描电镜照片可以看出,加入助催化剂共混物的两相结合紧密,脆断面的橡胶粒子剥离空洞减少,相容性提高。

The polystyrene （PS）/ethylene-propyl- ene-diene monomer （ EPDM ） blends were in-situ compatibilized through Friedel-Crafts alkylation reac- tion in melt state, and the influences of different cat- alyst systems of A1C13 and A1C13/NaC1 on the pro- perties and dynamic rheological behaviors of the blends were investigated. The results showed that the addition of cocatalyst NaC1 was favourable for in- haneing the grafting reaction between PS and EPDM and restraining the self-crosslinking reaction of EPDM, thus increasing the mechanical properties of the blends. The results of dynamic mechanical anal- ysis demonstrated that both the storage modulus and the glass transition temperature of PS in the blends decreased after the cocatalyst was added. The analysis of dynamic rheological behavior indicated that in low frequency range, the dynamic storage modulus, loss modulus and complex viscosity of the blends compatibilized by A1C1/NaC1 system were higher than those by A1C13 system, but the loss factor was lower. The scanning electron microscope photoes showed that PS and EPDM phases bound more tight- ly and the holes of exfoliated rubber particles on the fracture section decreased for the blend compatibi- lized by A1CI3/NaC1 system, implying that its com- patibilization was improved.