二氯二甲基硅烷在钼系催化丁二烯聚合中的分子量调变作用

The Role of Molecular Weight Regulation of Dichloro-Dimethyl Silane in the Synthesis of Polybutadiene with Molybdenum Catalyst System

在MoO_2Cl_2-(i-Bu)AlOPhCH_3体系催化丁二烯聚合中,Si(CH_3)_2Cl_2(简称CI)可用作活性添加剂和分子量调节剂。在Cl/Mo=0—300(摩尔比)范围内。有提高丁二烯聚合速率的作用,(?)w从85万降至50万,分子量分布加宽,对聚合物的微观结构无明显影响,1,2-链节含量在80％以上,顺1,4-链节约5％。

In the synthesis of polybutadiene with MoO_2Cl_2-(i-Bu)_2AlOPhCH_3 catalyst system, Si(CH_3)_2Cl_2 is used as an active additive oi catalytic system and a molecular weight regulator. In the range of Cl/Mo mole ratio from 0 to 300, the polymerization rate of butadiene increases when compared with the system without active additive, and the molecular weight of polymer, (?)_w, decreases sharply from 85×10~4 to 50×10~4 and the molecular weight distribution of polymer slightly broadens. The. polymer chain structure is not influenced by the additive, and the content of 1,2-chain unit and 1,4-unit in polymer are larger than 80％ and about 5％ respectively.