perfluorocyclobutane 聚合物的机械诱导裂变和随后的热修复
Hope M Klukovich1, Zachary S Kean, Scott T Iacono
1Department of Chemistry, Duke University, Durham, North Carolina 27708, United States.
Journal of the American Chemical Society
|October 5, 2011
概括
脉冲超声波通过机械化学链裂变分解高循环butan (PFCB) 聚合物. 由此产生的三乙烯末端组可以通过加热进行修复,从而使局部聚合物功能化成为可能.
科学领域:
- 聚合物化学 聚合物化学
- 机械化学 机械化学
- 材料科学 材料科学 材料科学
背景情况:
- perfluorocyclobutane (PFCB) 聚合物以其热稳定性而闻名.
- 了解聚合物降解机制对于材料设计和应用至关重要.
- 机械化学过程为聚合物修饰提供了替代途径.
研究的目的:
- 为了研究脉冲超声波对PFCB聚合物溶液的影响.
- 阐明降解机制并确定由此产生的末端组.
- 探索在机械化学损伤后修复聚合物的潜力.
主要方法:
- 对PFCB聚合物溶液进行脉冲超声波处理.
- (19) 核磁共振 (核磁共振) 光谱用于结构分析.
- 激进诱捕实验以探测反应机制.
- 热处理以评估可修复性.
主要成果:
- 脉冲超声波诱导了PFCB聚合物的链分裂和分子量减少.
- 机械化学降解通过循环逆转产生三乙烯末端组,与热降解不同.
- 通过将聚合物溶液加热到150°C以上,成功地对三乙烯末端组进行了修复.
- 立体化学分析和基因捕获表明,一个涉及1,4-二基中间体的阶段性裂变机制.
结论:
- 通过超声波对PFCB聚合物的机械化学降解产生独特的三乙烯末端组.
- 这些末端组可以在热条件下进行修复,为自愈材料提供了一条途径.
- 识别出了带有激进中间体的逐步机制,为应激地区的本地化功能化和交叉链接可能性提供了洞察力.
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