用共价有机框架支持的金属用于乙烯聚合
Bangban Zhu1, Kan Liu1, Liqiong Luo2
1State Key Laboratory of Chemical Engineering, College of Chemical and Biological Engineering Zhejiang University, Hangzhou, 310027, P. R. China.
Chemistry (Weinheim an der Bergstrasse, Germany)
|June 21, 2023
概括
共价有机框架 (COF) 材料有效地支持金属催化剂的烯聚合. 这种由COF支持的催化剂显著增加了活性,并增强了聚乙烯的特性,包括分子量和强度.
科学领域:
- 材料科学 材料科学 材料科学
- 聚合物化学 聚合物化学
- 催化剂是一种催化剂.
背景情况:
- 支持的催化剂提高了烯聚合性能.
- 开发具有可控结构和兼容性的支持催化剂对于高活性和产品质量至关重要.
研究的目的:
- 研究共价有机框架 (COF) 材料在乙烯聚合过程中作为金属催化剂的载体的使用.
- 用COF支持的催化剂评估生成的聚乙烯 (PE) 的催化活性和特性.
主要方法:
- 合成的COF材料作为金属催化剂Cp2ZrCl2.2.的载体.
- 使用同质和COF支持的催化剂进行乙烯聚合.
- 分析了产生的聚乙烯的催化活性,分子量,分子量分布,点,微观结构,抗拉强度和破裂时的延长.
主要成果:
- 与同质催化剂 (11.2×10^6 g·mol−1·h−1) 相比,COF支持的催化剂表现出明显更高的活性 (31.1×10^6 g·mol−1·h−1).
- 用COF支持的催化剂生产的聚乙烯显示重量平均分子量增加 (160到308kDa) 和分子量分布较窄 (3.3到2.2).
- 观察到增强的机械性能,包括增加拉伸强度 (19.0到30.7MPa) 和破裂时的延伸 (350到1400%).
结论:
- 氧化材料是烯聚合物聚合过程中金属催化剂的有效载体.
- COF支持增强了催化活性并改善了聚乙烯的特性,从而产生了高性能聚烯烯.
- 这种方法为开发先进的支持催化剂和功能性多聚烯提供了一个有前途的途径.
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