使用单位催化剂实现高乙烯聚合性能的战略
Lujain Alrais1, Walid Al Maksoud1, Baraa Werghi1
1KAUST Catalysis Center and Division of Physical Sciences and Engineering, King Abdullah University of Science and Technology, Thuwal, 23955-6900, Saudi Arabia.
Chemical communications (Cambridge, England)
|October 3, 2023
概括
这项研究开发了一种基于Ti(IV) 的新型催化剂,使用3D纤维化支 (KCC-1) 进行增强的乙烯聚合. 独特的催化剂结构显著提高了催化性能,产生高分子量高密度聚乙烯 (HDPE).
科学领域:
- 不同质的催化剂.
- 有机金属化学 有机金属化学
- 聚合催化剂的聚合.
背景情况:
- 表面有机金属化学原理是设计先进催化剂的关键.
- 具有特定形态和功能性的支对于催化剂性能至关重要.
- 乙烯聚合需要高效的催化剂来生产有价值的聚乙烯材料.
研究的目的:
- 合成和描述新型异质Ti (IV) 基催化剂用于乙烯聚合.
- 为了研究3D纤维化支 (KCC-1) 对催化活性和聚合物特性的影响.
- 探索功能化和结合在催化剂性能上的作用.
主要方法:
- 通过表面有机金属化学合成一个基于Ti (IV) 的催化剂,通过表面有机金属化学定在3D KCC-1基支持上.
- 使用FT-IR,固态NMR (1H, 13C),ICP-OES,CHNS分析和XPS进行了表征.
- 在乙烯聚合过程中催化性能的评估和由此产生的高密度聚乙烯 (HDPE) 的分析.
主要成果:
- 一个新的异质催化剂["Si-O-Si") "Si-O-") "Al-O-) TiNp3]成功合成和表征.
- KCC-1的3D纤维形态和功能增强了反应剂扩散和定.
- 催化剂在乙烯聚合过程中表现出了显著的活性,产生了分子量为3,200,000 g/mol的HDPE,PDI为2.3.
结论:
- 结合功能化支的3D形态和电子特性,显著提高了催化性能.
- 开发的基于Ti (IV) 的催化剂对于生产高分子量HDPE非常有效.
- 该研究强调了支设计在烯聚合物的异质催化中的重要性.
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