作为闭环可回收热塑性材料的高摩尔质聚碳酸
Gloria Rosetto1, Fernando Vidal1, Thomas M McGuire1
1Department of Chemistry, Chemistry Research Laboratory, University of Oxford, 12 Mansfield Rd, Oxford OX1 3TA, U.K.
Journal of the American Chemical Society
|March 14, 2024
概括
这项研究引入了一种新的Mg(II) Co(II) 催化剂,用于有效的二氧化碳 (CO2) 共聚合,产生高分子质量的可回收聚碳酸. 这种新催化剂可实现调节性质和有效的脱聚合,为聚合物制造提供可持续的替代品.
科学领域:
- 聚合物化学
- 有机金属催化
- 可持续的材料
背景情况:
- 减少聚合物制造中的温室气体排放至关重要.
- 通过环开合聚合 (ROCOP) 的二氧化碳 (CO2) 利用提供了 CO2 衍生聚碳酸的途径.
- 高摩尔质聚碳酸的有效催化剂及其结构性质关系仍未得到充分研究.
研究的目的:
- 从二氧化碳开发高摩尔质聚碳酸的有效催化剂.
- 阐明这些新型聚碳酸的结构-性质关系,加工和可回收性.
- 探索基于二氧化碳的热塑料作为可持续替代品的潜力.
主要方法:
- 开发一种新的有机金属Mg (II) Co (II) 催化剂.
- 用各种双环环氧化物对二氧化碳进行环开合聚合 (ROCOP).
- 由此产生的聚碳酸盐的特征包括分子量,热性质 (Tg,Td) 和质性行为.
- 通过再加工和催化解聚合物化的可回收性评估.
主要成果:
- (II) 碳 (II) 催化剂表现出高生产率,低负载耐受性和出色的聚合控制.
- 合成了高分子量聚碳酸盐 (Mn > 100 kg mol-1),包括PCHC,PvCHC,PeCHC和PCPC.
- 这些无形热塑性材料具有高玻璃过渡温度 (85126 °C) 和热稳定性 (>260 °C).
- 与PCHC相比,聚烯碳酸 (PCPC) 的纠分子量和粘度显著降低.
- 所有合成的聚合物均可通过再处理或催化脱聚合回收.
结论:
- 这种新型的Mg (II) Co (II) 催化剂能够有效地从二氧化碳中合成高摩尔质量的可回收聚碳酸盐.
- 可调节的材料特性可以通过改变循环环替代剂来实现.
- 由于其有利的风湿性质,PCPC显示出有前途的热塑性潜力.
- 开发的催化系统促进了聚合物合成和选择性脱聚合,促进了塑料循环经济.
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