一种多用途的共子添加剂,用于彻底可回收的乙烯基衍生聚合物
Autumn M Mineo1, Reika Katsumata1
1Department of Polymer Science and Engineering, University of Massachusetts Amherst, Amherst, MA 01003, USA.
Angewandte Chemie (International ed. in English)
|November 29, 2023
概括
这项研究引入了一种新的方法,通过添加循环烯酸硫化物添加剂来化学回收乙烯聚合物. 这允许控制的链分裂和再延伸,使得聚合物废物的闭环循环回收和再循环.
科学领域:
- 聚合物化学 聚合物化学
- 材料科学 材料科学 材料科学
- 可持续化学 可持续化学
背景情况:
- 乙烯基衍生聚合物占全球聚合物生产的很大一部分.
- 这些聚合物中稳定的碳-碳键对化学回收提出了重大挑战.
- 现有的回收方法往往在效率和材料降解方面扎.
研究的目的:
- 开发一种通用方法,用于化学回收乙烯基衍生聚合物.
- 在聚合物骨干中引入动态图案,以控制降解和再生.
- 为了使消费后的聚合物废物能够进行闭环回收和再循环.
主要方法:
- 在自由基条件下,用循环化硫化物 (CAS) 添加剂对乙烯基单体的共聚化.
- 在聚合后,通过添加-碎片-转移 (AFT) 进行基质重组,以实现链分裂.
- 选择性诱导链裂使用小分子基.
- 用单体重新扩展寡合体,以获得可调节的质量和阻断共聚物.
主要成果:
- 证明了CAS与各种乙烯基单体的成功共聚合,引入动态主链化硫酸基因.
- 实现了聚合物的选择性链裂变,将摩尔质量降低到原始的14%.
- 展示了高效的寡合体再延伸,保留了基硫化末端组用于进一步的聚合.
- 通过甲基甲基酸盐和烯成功完成了两次裂变延伸循环,而没有增加分散性.
- 通过寡合体延伸合成块共聚合物,说明上循环的潜力.
结论:
- 开发的基于AFT的方法提供了一种通用和高效的方法,用于化学回收乙烯基衍生聚合物.
- 这种技术在极端条件下实现了真正的闭环循环回收.
- 该方法可促进废弃聚合物的上循环转化为更高价值的材料,如块共聚合物.
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