多单体熔融接枝聚丙烯的微相分离结构

用熔融接枝方法制备了一系列不同接枝率的GMA(甲基丙烯酸缩水甘油酯)/St(苯乙烯)多单体接枝聚丙烯PP-g-(GMA-co-St)],基体聚丙烯包括均聚聚丙烯和共聚聚丙烯(乙烯的摩尔分数分别是6.0%,12%,33%).接枝聚丙烯经过分离提纯后,用四氧化钌(RuO₄)进行染色,然后用透射电子显微镜(TEM)观察其微观形态.发现在接枝聚丙烯中形成了长程有序的、球状的微相分离结构,这种在分子量和分子结构都是多分散体系中形成的微相分离结构尚未见报道.同时,研究了基体聚丙烯中乙烯链段的含量以及接枝率对于接枝聚丙烯微观形态的影响.

Microphase Separation Structure Formed in GMA/St Multi-monomer Melt Grafted Polypropylene

The glycidyl methacrylate(GMA) and styrene(St) multi-monomer grafted polypropylene(PP),PP-g-(GMA-co-St),with various grafting degrees were prepared by melt-grafting process. The homo-PP and ethylene-co-polypropylene with different contents of ethylene were chosen to be backbone PP for the grafting process. After purification,PP-g-(GMA-co-St) was stained by RuO 4,and its microphase morphology was observed by Transmission Electron Microscope(TEM). The microphase separation morphology, i.e . spherical long-range order structure was found in the grafted PP. Such nano-structure morphology formed in melt-grafted polymer was unique and original. The effects of E block fractions in EP copolymer and grafting degree on the microphase morphology were discussed. This study indicated that even in the melt grafting system,where molecular weight and molecular architecture are both multi-dispersed,copolymers with long grafts could also be separated in a microphase into long-range order structures.