通过机制引导的可分解聚甲酸的可裂变共体的发现
Kwangwook Ko1, David J Lundberg2, Alayna M Johnson1
1Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States.
Journal of the American Chemical Society
|March 25, 2024
概括
研究人员开发了新的可裂变共聚物 (CCs),能够与甲基甲酸盐 (MMA) 有效共聚. 这一突破使得可降解的聚合物具有与标准PMMA相似的特性,为可持续的聚合物设计提供了新的途径.
科学领域:
- 聚合物化学
- 材料科学
- 有机合成
背景情况:
- 可切割共聚物 (CCs) 对于制造可分解的聚合物至关重要.
- 基于烯酸的CC,如二[c,e]-氧-5(7H) - (DOT),已经显示出对各种乙烯基聚合物的承诺.
- 然而,硫黄CCs并没有与甲酸盐有效共聚化.
研究的目的:
- 设计和合成能够与甲基烯酸盐有效共聚的新型烯酸盐.
- 通过基性聚合,使可解构的聚甲基酸 (dPMMA) 的产生成为可能.
- 研究所产生的聚合物的共聚化行为和解构.
主要方法:
- 用基稳定替代剂设计和合成基功能化硫黄 (bDOT).
- 机械分析以了解和调整甲基甲酸盐 (MMA) 的共聚反应性.
- 大量自由基共聚化以产生高摩尔质量的dPMMA.
主要成果:
- 一种新的bDOT,F-p-CF3PhDOT,与MMA进行了高效和几乎随机的共聚化.
- 高分子质量dPMMA (Mn>120kDa) 在低CC内含量 (1.8-3.8mol%) 的情况下进行合成.
- dPMMA的热力学性能与PMMA相似,但在轻微的氨解下可以降解为低摩尔质量碎片 (<6.5kDa).
结论:
- 这项研究介绍了第一个能够与MMA有效共聚的基环开放CC,而无需交叉链接.
- 开发的bDOT为设计具有可调节性质的可分解聚合物提供了途径.
- 这些发现为更可持续的聚合物材料和回收策略铺平了道路.
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