乙烯与 norbornene 的活共聚合,由 bis ((pyrrolide-imine) 复合物与 MAO 催化
Yasunori Yoshida1, Jun-ichi Mohri, Sei-ichi Ishii
1R & D Center, Mitsui Chemicals, Inc., 580-32 Nagaura, Sodegaura, Chiba, 299-0265, Japan.
Journal of the American Chemical Society
|September 24, 2004
概括
新的催化剂高效地共聚乙烯和诺伯,产生高诺伯含量的独特聚合物. 在特定条件下,这些催化剂使生物聚合成为可能,产生高分子量,单分散性共聚合物和阻断性共聚合物,用于先进的材料应用.
科学领域:
- 聚合物化学 聚合物化学
- 催化剂是一种催化剂.
- 材料科学 材料科学 材料科学
背景情况:
- 添加型聚合机制对于合成新型聚合物架构至关重要.
- 基于的催化剂被广泛用于olefin聚合.
- 控制共聚合物组成和分子量是开发先进材料的关键.
研究的目的:
- 为了研究 bis ((pyrrolide-imine) Ti 复合物与甲基氧 (MAO) 作为乙烯和诺波共聚合的催化剂的有效性.
- 探索高norbornene合并和受控活体聚合的潜力.
- 合成和表征独特的共聚合物结构,包括块共聚合物.
主要方法:
- 乙烯和诺波伦烯的共聚化,使用bis () 复合物和MAO.
- 使用诸如核磁共振 (NMR) 光谱和传输电子显微镜 (TEM) 等技术对共聚物进行表征.
- 通过密度函数理论 (DFT) 计算,研究聚合行为和催化剂特性.
主要成果:
- 催化剂显示出高的norbornene合并,超过了像 (CGC) 这样的传统催化剂.
- 在特定的norbornene/乙烯比率下实现了客厅温度共聚合,产生高分子量,单分散共聚物 (M(w) /M(n) <1.20).
- 独特的块共聚合物已成功合成,显示出具有结晶和无形段相连的材料的潜力.
结论:
- 双氧化物-胺基) Ti 复合物是乙烯-诺波共聚合的高效催化剂,提供优质的诺波合并.
- 催化剂促进了受控的生物聚合,使得明确的共聚合物和阻断共聚合物的合成成为可能.
- 由此产生的共聚合物具有独特的特性,表明它们对新型材料应用的潜力.
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