乙烯聚合在金属有机框架支持的conocene 复合体上
Yaqi Wu1,2, Joren M Dorresteijn1, Bert M Weckhuysen1
1Inorganic Chemistry and Catalysis group, Institute for Sustainable and Circular Chemistry and Debye Institute for Nanomaterials Science, Utrecht University, Universiteitsweg 99, 3584 CG Utrecht, The Netherlands.
ACS catalysis
|June 13, 2024
概括
金属有机框架 (MOF) 在烯聚合物聚合过程中作为金属催化剂的有效支. 定制MOF属性可以控制聚乙烯的特性,包括超高分子量聚乙烯 (UHMWPE) 的生产.
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:
- 均的金属催化剂在烯聚合过程中存在局限性.
- 固定金属在固体支上提供了一种解决方案,以提高催化性能.
- 金属有机框架 (MOFs) 呈现可调节的多孔结构,适用于催化剂支.
研究的目的:
- 研究MOF特性 (孔径大小,链接器,表面群) 对基于金属的乙烯聚合物的影响.
- 探索由不同MOF支持的金属催化剂的激活和失活机制.
- 使用MOF支持的催化剂合成具有受控分子量的聚乙烯.
主要方法:
- 三种不同的基于Zn的MOF (MOF-5,IRMOF-3,ZIF-8) 的合成和激活.
- 用甲基氨酸 (MAO) 激活MOF支持的conocene复合体.
- 乙烯聚合实验,然后使用XRD,SEM,GPC,DSC和FT-IR进行材料表征.
主要成果:
- MOF结构显著影响催化剂的激活,关闭和多个活性位点的形成.
- 不同的MOF支产生的聚乙烯具有不同的特性.
- 超高分子量聚乙烯 (UHMWPE) 使用IRMOF-3作为支物成功合成.
结论:
- 在乙烯聚合过程中,MOF是金属催化剂可调节的多孔支器.
- MOFs,MAO和硫黄素之间的相互作用对催化活性至关重要.
- 支持MOF的金属催化提供了一条定制聚合物特性的途径.
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