Syndiospecific styrene polymerization with CpTiCl3/MAO:: Effects of the order of reactant addition on polymerization and polymer properties

被引：6

作者：

Huang, B

Cao, K

Li, BG

Zhu, SP ^{[1
]}

机构：

[1] McMaster Univ, Dept Chem Engn, Hamilton, ON L8S 4L9, Canada

[2] Zhejiang Univ, Dept Chem Engn, Div Polymer, State Key Lab Chem Engn, Hangzhou 310027, Peoples R China

来源：

JOURNAL OF APPLIED POLYMER SCIENCE | 2004年 / 94卷 / 04期

关键词：

syndiotactic polystyrene; metallocene polymerization; methylaluminoxane; titanocene;

D O I：

10.1002/app.21050

中图分类号：

O63 [高分子化学（高聚物）];

学科分类号：

070305 ; 080501 ; 081704 ;

摘要：

Syndiospecific styrene (St) polymerization, catalyzed by the CpTiCl3/methylaluminoxane (MAO) system, was investigated using two different activation procedures. The polymerization parameters included polymerization time, temperature (similar to25-100degreesC), ratio of [Al]/[Ti] (similar to100-1000), and catalyst precursor concentration (similar to0.5-10.0 x 10(-4) mol Ti/L). It was found that adding reactants in the order of (CpTiCl3 + MAO) + St (Injection of Styrene mode) gave much higher monomer conversion rates, higher weight-average molecular weights, and narrower molecular weight distributions than for the (St + MAO) + CpTiCl3 (Injection of Catalyst mode). The former also yielded significantly higher syndiotacticity fractions. Differential scanning calorimetry measurements showed multiple peaks exhibiting polymorphism in crystalline syndiotactic polystyrene samples. (C) 2004 Wiley Periodicals, Inc.

引用

页码：1449 / 1455

页数：7

共 48 条

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