异金属Li/Zn,Li/Al和Li/In催化剂用于rac-lactide环开聚合:有"有"或"没有"的途径?
Thitirat Piyawongsiri1, Anand J Gaston2, Maisarah Abdul Rahman2
1Department of Materials Science and Engineering, School of Molecular Science and Engineering, Vidyasirimedhi Institute of Science and Technology (VISTEC) Thailand khamphee.p@vistec.ac.th.
含有和的双金属催化剂在生产聚合物的乳化环开放聚合过程中表现出高活性. 金属的组合和属性如易斯酸度会影响催化效率.
科学领域:
- 聚合物化学
- 有机金属化学
- 材料科学
背景情况:
- 乳化物的环开聚合 (ROP) 是合成可生物降解的形聚合物的关键.
- 双金属催化剂具有很高的活性,但在异金属系统中合作的起源需要进一步的研究.
- 了解金属组合,特别是与过渡或过渡后金属的金属,对于催化剂设计至关重要.
研究的目的:
- 合成和表征与,和的新型同金属和异金属复合物.
- 调查这些复合物的催化活性在拉西姆乳酸的环开聚合过程中.
- 阐明金属的特性和特性在催化剂性能和反应途径中的作用.
主要方法:
- 合成和单晶X射线衍射以为基础的同型和异型金属复合物与联体.
- 使用环氧化剂启动器在血清乳酸ROP中合成复合物的催化评估.
- 密度功能理论 (DFT) 研究以分析影响催化活性的结构和电子性质.
主要成果:
- 已成功合成和特征化LLiZnCl,LLiAlCl2和LLiInCl2等金属复合物.
- 所有合成的异金属复合物都在乳酸ROP中表现出活性,其中LLiInCl2是最有效的.
- 发现同金属复合物LLi2是不活跃的,这突显了异金属合作的重要性.
- DFT和结构分析表明,氧性,易斯酸性和电子阴性差异决定了催化性能.
结论:
- 异金属合作对于有效的乳酸ROP至关重要,同金属LLi2复合物的不活性证明了这一点.
- 与,或的结合可以导致聚合成的高活性催化剂.
- 金属特性如氧性和易斯酸性,受金属特征的影响,是决定催化剂效率和反应机制的关键因素.
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