乙醇乙烯是环开放转化聚合物的有效单体:可降解和可解聚合的聚二二)
1Department of Chemistry , Stanford University , Stanford , California 94305 , United States.
Journal of the American Chemical Society
|December 28, 2019
概括
研究人员实现了环开转化聚合 (ROMP) 的循环乙烯,创造了新的可降解聚乙烯. 这一突破使催化剂回收和聚合物脱聚合成为可能,提供了可持续的材料解决方案.
科学领域:
- 聚合物化学
- 有机合成
- 材料科学
背景情况:
- 乙醇通常会灭格拉布斯催化剂,限制它们在聚合过程中的使用.
- 基复合物可以在富含电子的基转化过程中保持活性.
研究的目的:
- 为了证明循环乙醇的环开放转化聚合 (ROMP).
- 开发可降解和可脱聚合的聚乙烯.
- 建立催化剂停用和清除的方法.
主要方法:
- 使用Grubbs催化剂作为ROMP的单体.
- 使用启动载荷和链传递剂控制的聚合物分子量.
- 开发了用于催化剂去除的H2O2氧化方案.
主要成果:
- 实现了循环乙烯的ROMP的第一个例子,产生了聚二.
- 产生的聚合物具有完美的区域规律性和可控制的分子重量.
- 证明了催化剂的失活,去除和随后的聚合物脱聚合/降解.
结论:
- 循环乙烯是ROMP的可活单体,产生新的可降解聚合物.
- 合成的聚二可回收为单体,可降解为小分子.
- 这项研究为使用乙醇单体的可持续聚合物开发开辟了新的途径.
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