橡胶相具有交联结构的新型抗冲聚丙烯合金

NEW IMPACT POLYPROPYLENE ALLOY CONTAINING CROSS-LINKING RUBBER PHASE

利用具有"颗粒反应器技术(RGT)"特征的Ziegler-Natta催化剂进行丙烯多相共聚(丙烯均聚+乙烯/丙烯无规共聚),通过在乙丙共聚阶段引入双烯烃单体1,9-癸二烯,使乙丙共聚物在聚合的同时实现交联,制备了新型抗冲聚丙烯合金.聚合反应结果表明,1,9-癸二烯可参与乙丙共聚,同时对聚合反应速率和共聚物组成影响较小;1,9-癸二烯使乙丙共聚物发生支化/部分交联,合金聚合物的熔体流动速率在引入1,9-癸二烯后显著降低,且凝胶含量随1,9-癸二烯用量的增加而增大.形态研究结果表明,乙丙共聚物的交联显著降低了其在聚丙烯基体中的分散尺度,提高了分散均匀性,分散相粒径随支化/交联程度提高而减小.力学性能测试结果表明,乙丙共聚物的交联使合金聚合物在保持较高韧性的同时显著提升了刚性,有利于实现抗冲聚丙烯合金的刚韧平衡.

Based on propylene heterogeneous copolymerization with the aid of RGT-aligned Ziegler-Natta catalyst, a novel in-reactor PP alloy with cross-linking EPR has been prepared through a,w-diene such as 1, 9-decadiene （DD） addition. The polymerization results show that DD monomer has a good reactivity with ethylene and propylene monomers and a minor effect on the composition of copolymers. DD monomer has been successfully bonded into the backbones of ethylene-propylene random copolymer, resulting in branching and cross-linking of the EPR. The melt flow rate （MFR） of the new hiPP shows an obvious drop after the introduction of DD monomer;while the gel content increases with the increasing of DD monomer. Morphology study by SEM reveals that cross-linking EPR greatly promotes the dispersivity of rubber phase in PP matrix. The size of rubber particles reduces with the branching and cross-linking density. The results of mechanical properties tests indicate that cross-linking EPR can potentially enhance the toughness of hiPP without or with little compromise of the rigidity and processibility,which is very meaningful to achieve the rigidity-toughness balance of PP resins.