通过所有环的化学回收来改善循环
Vincent Nieboer1, Karin Odelius1,2, Peter Olsén2,3
1Department of Fibre and Polymer Technology, KTH Royal Institute of Technology, Stockholm, Sweden.
Angewandte Chemie (International ed. in English)
|February 28, 2025
概括
本研究介绍了聚合物的化学回收到所有环 (CRR),这是一个多维的方法,克服了传统单体回收的局限性. 这种基于环链平衡 (RCE) 的新概念,可以有效地回收具有挑战性的聚合物.
科学领域:
- 聚合物化学 聚合物化学
- 可持续材料科学科学 可持续材料科学
- 化学工程是化学工程的重要组成部分.
背景情况:
- 亚利法性聚合物具有比PE和PP等传统塑料具有竞争力的性能.
- 化学回收到单体 (CRM) 是一个关键的优势,但并非所有的聚烯都能接受这一过程.
- CRM的热力学可行性通常通过环开聚合过程中自由能量变化 (∆GROP) 来评估,这是一个单维的测量.
研究的目的:
- 通过达到环链平衡 (RCE) 将化学回收到所有环 (CRR) 的多维概念引入.
- 为了证明回收的热力学景观是多维的,涉及不仅仅是单质聚合物的平衡.
- 为了使得聚合物难以通过传统的CRM回收利用,启用CRR.
主要方法:
- 开发一个高度活跃的催化系统以实现RCE.
- 使用环链平衡期间自由能量变化的热力学分析 (∆GRCE).
- 应用于CRR概念的多-ε-caprolactone,多-pentadecalactone和混合聚合物系统.
主要成果:
- 通过使用新型催化系统,成功实施了多维CRR方法.
- 对CRR (∆GRCE) 的热力学驱动力与CRM (∆GROP) 的热力学驱动力有很大的不同.
- 对于以前认为难以回收的聚合物,包括聚ε-烯和聚五甲,实现了高效的CRR.
结论:
- 该研究提出了一种新的一般概念,用于在聚合物回收中关闭材料循环.
- 基于RCE和∆GRCE的CRR提供了一个比传统CRM更全面,更有效的策略.
- 这项工作扩大了可回收聚合物的范围,并推动了可持续的材料管理.
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