阶梯烯-诺伯烯块共聚物的合成和机械化学激活
Jessica K Su1, John D Feist1, Jinghui Yang1
1Department of Chemistry , Stanford University , Stanford , California 94305 , United States.
Journal of the American Chemical Society
|September 20, 2018
概括
研究人员使用聚拉丁烯 (PLDE) 开发了新的应力块共聚合物,在机械刺激时转化为聚乙烯 (PA). 这些新材料为应力反应的聚合物和自我组装行为提供了新的可能性.
科学领域:
- 聚合物化学
- 材料科学
- 机械化学
背景情况:
- 聚拉德 (PLDE) 是一种在机械作用下转化为多乙烯 (PA) 的多机.
- 由于催化剂失活,开发具有应力细分的块共聚物 (BCP) 是一个挑战.
研究的目的:
- 合成一种新型的BCP,其中包含一个强度响应的PLDE块.
- 为成功的BCP合成优化聚合条件.
- 研究这些BCP的机械激活和特性.
主要方法:
- 序列环开放转化聚合诺博和甲.
- 优化反应时间和温度以保持催化剂活性.
- 声化学激活以诱导PLDE转化为PA.
主要成果:
- 已经成功合成了前所未有的含有强力反应的PLDE阻塞的BCP.
- 通过超声波将PLDE段控制转化为PA.
- 观察到独特的吸收模式,表明梯度单元的非连续激活,最大吸收 λ ≥ 600 nm.
结论:
- 建立了对多机械型BCP的访问.
- 这些BCP允许具有可调节溶液和固态自组装的新应力材料.
- 将多机械体纳入多种材料系统的潜力.
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