(III) /K (I) 异种核聚合催化剂显示快速率和高选择性对聚聚
Edward J K Shellard1, Wilfred T Diment1, Diego A Resendiz-Lara1
1Chemistry Research Laboratory, Department of Chemistry, University of Oxford, 12 Mansfield Road, Oxford OX1 3TA, U.K.
概括
新的Al (III) /K (I) 催化剂可通过环开放共聚合来有效合成基终结聚 (聚). 这些催化剂克服了酒精抑制,加速反应并产生具有受控分子量的高质量聚合物.
科学领域:
- 聚合物化学 聚合物化学
- 催化剂是一种催化剂.
- 有机合成 有机合成
背景情况:
- 聚合物对于聚氨,树脂,涂料和表面活性剂至关重要.
- 通过环氧化/无水化开环共聚合 (ROCOP) 来控制聚的合成至关重要.
- 现有的催化剂通常被酒精抑制,限制了聚醇合成.
研究的目的:
- 开发用于高效聚合成的新型催化剂.
- 在ROCOP中克服酒精抑制.
- 为了生产具有受控性质的基电性聚/乙.
主要方法:
- 合成和应用稳定在空气中的Al (III) /K (I) 异种核催化剂.
- 使用不同度的二醇 (链转移剂) 的环开环共聚氧化和无水化物.
- 聚合物性质的表征,包括分子质量,分散性和结选择性.
主要成果:
- (III) /K (I) 催化剂在ROCOP中表现出高活性和选择性.
- 酒精加快了反应,而增加的二醇量增加了活性.
- 实现了具有可控摩尔质量 (400-20400 g mol-1) 和低分散度 (<1.19) 的基电性聚/乙烯的生产.
- 观察到高链接选择性 (>99%).
- 1890小时-1的周转频率 (TOF) 在最佳的催化剂和二醇负载下实现.
结论:
- (III) /K (I) 催化剂在通过ROCOP生产聚聚醇方面非常有效.
- 这些催化剂克服了酒精抑制,并使控制合成成为可能.
- 推用于聚聚的未来工业生产和应用开发.
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