开放和闭环循环回收:高活性双胺聚合催化剂用于聚合物的脱聚合
Tabea Becker1,2, A Hermann1,2, Nazik Saritas1
1Institute of Inorganic Chemistry, RWTH Aachen University, Landoltweg 1a, 52074, Aachen, Germany.
ChemSusChem
|June 13, 2024
概括
一种新的催化剂通过脱聚合有效地回收聚乳酸 (PLA) 和聚烯酸 (PCL) 等聚合物. 这一突破使高价值产品的回收成为可能,并支持循环经济,减少塑料垃圾.
科学领域:
- 聚合物化学 聚合物化学
- 催化剂是一种催化剂.
- 可持续材料 可持续材料
背景情况:
- 聚的化学回收对于循环经济至关重要.
- 为聚降解开发高效和选择性的催化剂是一个持续的挑战.
- 目前的方法往往需要恶劣的条件或产生低价值的产品.
研究的目的:
- 引入和评估一种新型的异质N,N-双胺复合物[Zn(DMEG2ch) ][Zn(OTf) 2·THF,用于 (生物) 聚合物的化学回收.
- 研究催化剂在环开聚合 (ROP) 和脱聚合中的活性,特别是对于聚乳酸 (PLA) 和聚烯酸 (PCL).
- 探索催化剂可回收性和单体的直接回收,用于开放或闭环回收.
主要方法:
- 合成和表征N,N-bisguanidine复合物的合成和表征.
- 通过酒精分解对PLA脱聚合物的动力学和热力学研究.
- 测试催化剂在降解PLA,PCL及其与PET混合物的性能.
- 研究使用乙醇和单体回收的催化剂回收.
主要成果:
- 复合物[Zn(DMEG2ch) 2](OTf) 2·THF在乳化物 (LA) 和e-caprolactone (CL) 的ROP中表现出高活性.
- 在温和的条件下实现了PLA高价值酸乳酸盐的高效脱聚合.
- 证明了成功的催化剂回收和直接从PLA中回收LA.
- 从PLA/PET混合物中选择性降解PLA,并实现PLA/PCL混合物的级联回收.
结论:
- 开发的催化剂具有高度活性,并且适用于 (生物) 聚化学回收.
- 这种催化剂促进了有价值的单体的回收,并使开放循环和闭环循环循环回收通道成为可能.
- 这些发现有助于建立循环塑料经济和减轻塑料污染.
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