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用负载型钛系催化剂ＭｇＣｌ_２／ＴｉＣＬ_４，ＮｄＣｌ_３／ＡｌＥｔ_３（ＳＮ－１催化剂）在甲苯溶剂中进行苯乙烯的定向聚合，单体转化率。催化效率和产物的等规度随单体浓度增大先是提高，达到最大值后，逐渐下降，等规度最高可达９８％．产物的分子量则随单体浓度增大而增大．ＤＳＣ测定表明，产物中的无规物（ａＰＳ）有利于等规聚苯乙烯（ｉＰＳ）结晶，但对结晶的熔点有降低作用．向产物加入更多的ａＰＳ则由于稀释效应而使ｉＰＳ的结晶度线性下降．在聚乙烯（ＰＥ）／ｉＰＳ共混物中，ＰＥ含量对ｉＰＳ的结晶度无显著影响；但在聚碳酸酯（ＰＣ）／ｉＰＳ共混物中，ＰＣ含量对ｉＰＳ的结晶度影响较复杂．
Polymerization of Styrene in Toluene Solvent with Supported Titanium Catalysts MgCl_2 / TiCl_4, NdCl_3 / AlEt_3 (SN-1 Catalyst), Monomer Conversion. The catalytic efficiency and the isotacticity of the product increase first with the increase of the monomer concentration. After reaching the maximum value, the declines gradually and the isotactic index up to 98%. The molecular weight of the product increases with the monomer concentration. DSC measurements showed that aPS in the product favored iPS crystallisation but had a reduced effect on the melting point of the crystallisation. Adding more aPS to the product results in a linear decrease in iPS crystallinity due to the dilution effect. In the PE / iPS blends, PE content had no significant effect on iPS crystallinity; however, the PC content in PC / iPS blends had a more complicated effect on the crystallinity of iPS.