通过合理设计单位催化剂,在工业相关的温度下获得活性,分子量和战术性的平衡调节,以在工业相关的温度下进行综合战术烯聚合
Yong-Qing Li1,2, Yu-Qing Peng2, Gui-Ping Cao1
1UNILAB, State Key Laboratory of Chemical Engineering, East China University of Science and Technology, Shanghai, P. R. China.
Macromolecular rapid communications
|July 10, 2025
概括
这项研究开发了新型的催化剂 (Zr1-Zr3) 用于合成聚烯 (sPP) 生产. 催化剂在工业温度下实现了高活性,分子量和协同作用的平衡,从而使得聚合物具有量身定制的特性.
科学领域:
- 催化剂是一种催化剂.
- 聚合物化学 聚合物化学
- 材料科学 材料科学 材料科学
背景情况:
- 单位催化剂 (SSC) 对烯协调聚合至关重要,产生高性能聚烯.
- 优化SSC结构往往会导致在聚合活性,分子量和综合性中进行权衡.
研究的目的:
- 合成具有量身定制的硬质和电子性质的新型复合物 (Zr1-Zr3).
- 研究这些复合物的应用在工业相关温度下的协同战术烯聚合.
- 建立催化剂结构,聚合行为和由此产生的聚合物特性之间的关系.
主要方法:
- 合成环二烯-烯 (Cp-Flu) 安萨-齐尔科诺森与不同的二替代基.
- 在30°C和50°C的Propylene聚合试验.
- 聚合物属性的表征,包括分子重量,综合性,抗拉强度和弹性行为.
- 使用分子建模分析催化剂结构和固态环境.
主要成果:
- Zr2和Zr3复合物表现出平衡的聚合性能,达到高活性 (高达4.5×107 g/mol·h),高分子量 (高达60.2×104),高协同毒性 (高达87.1%).
- 在工业温度 (30°C和50°C) 中,性能保持不变.
- 由此产生的协同毒性聚烯 (sPP) 的机械和弹性特性与分子量和协同毒性相关.
结论:
- 在Cp-Flu ansa-zirconocenes上使用2替代的基组的梯度调制策略,可以同时控制活性,分子量和联合毒性.
- 远程电子调制,而不是Zr中心周围的直接硬体阻碍,是实现平衡聚合性能的关键.
- 这种方法允许生产针对特定应用的可调节性质的sPP.
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