聚碳酸二醇及其聚酸块共聚合物的受控合成,使用氨基双 (酸) 氧化复合物
Kaijie Ni1, Louise N Dawe2, Amy A Sarjeant3
1Department of Chemistry, Memorial University of Newfoundland, St John's, Newfoundland, A1C 5S7, Canada. ckozak@mun.ca.
Dalton transactions (Cambridge, England : 2003)
|November 15, 2023
概括
一个 (III) 复合物有效地将二氧化碳 (CO2) 和环氧化物 (CHO) 共聚合成聚碳酸盐二醇. 这些二醇启动rac-lactide的环开放聚合,产生具有调节性质和增强热稳定性的块共聚物.
科学领域:
- 聚合物化学 聚合物化学
- 有机金属化学 有机金属化学
- 材料科学 材料科学 材料科学
背景情况:
- 从二氧化碳中开发可持续的聚合物对于环境修复至关重要.
- 复合物已被证明是聚合反应中的催化剂.
- 聚碳酸盐和聚酸盐是生物可降解和生物相容的聚合物的重要类别.
研究的目的:
- 通过使用新型 (III) 复合物,通过CO2和环氧化物共聚合合成聚碳酸二醇.
- 为了利用合成的聚碳酸二醇作为macroinitiators的rac-lactide的环开放聚合.
- 为了研究rac-lactide结合对产生的ABA型块共聚合物的热性质的影响.
主要方法:
- 使用二胺-双 (酸) (III) 复合物 (CrOH[L]) 和四甲基氧化物,对二氧化碳和环氧化物进行共聚合.
- 通过使用1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) 合成的聚碳酸二醇启动的rac-lactide的环开聚合.
- 使用GPC,DSC和TGA等技术对聚合物进行表征,以确定分子质量,分散性,玻璃过渡温度 (Tg) 和分解温度 (Td).
主要成果:
- 有效的CO2和CHO共聚化成聚碳酸二醇,其摩尔质量为6.3公斤mol-1.
- 成功合成了ABA类型的块共聚合物,具有受控的分子质量和狭窄的分散度.
- 证明了rac-lactide含量和Tg之间的反向关系,以及与Td的正相关性.
- 使用基于的共催化剂,合成含的聚碳酸盐,其摩尔质量高 (28.5公斤mol-1),分散度窄 (1.13),Tg为110°C,Td超过300°C.
结论:
- 开发的 (III) 催化剂系统有效地从二氧化碳和CHO中产生聚碳酸二醇.
- 合成的聚碳酸二醇作为有效的宏基发起剂,用于生产明确定义的聚酸聚碳酸块共聚合物.
- 该研究强调了通过受控块共聚合来调整聚合物特性 (包括热稳定性) 的潜力.
- 通过共催化剂的结合导致具有显著增强热性能的聚碳酸盐.
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