合成了2种限制几何构型稀土配合物(IndCH2-Py)2Sc(CH2 SiMe3)(1)、(FluCH2-Py)Sc(CH2 SiMe3)2(2) (Py=Pyridyl；Ind=Indenyl；Flu=Fluorenyl),在有机硼盐与烷基铝的活化下,表现出了不同的催化行为；配合物2组成的催化体系可以引发苯乙烯与乙烯共聚,得到多嵌段共聚物,共聚活性最高达1.21×103 kg/(mol(Sc) ·h).该共聚物经化学溶解性实验和凝胶渗透色谱表征,证明无均聚物存在.共聚物中,聚苯乙烯链段保持间规性,并且其含量可调.由示差扫描量热法得到了不同投料比所得共聚物的熔点(237 ～ 257℃).共聚物的相对分子质量为3.2 ×104 ～10.7 ×104,相对分子质量分布为2.05 ～2.34.
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