解反应性差异:室温环开转化聚合 (ROMP) 与前端ROMP
Jacob J Lessard1, Edgar B Mejia2, Abbie J Kim1
1Beckman Institute for Advanced Science and Technology, Department of Chemistry, University of Illinois Urbana-Champaign, Urbana, Illinois 61801, United States of America.
Journal of the American Chemical Society
|March 5, 2024
概括
前环开放转化聚合 (FROMP) 提供了对树脂反应性的增强控制,改善了寿命和聚合速度. 在FROMP系统中,较高的启动度意外地提高了性能.
科学领域:
- 聚合物化学
- 材料科学
- 化学工程
背景情况:
- 环开转化聚合 (ROMP) 是一种多功能聚合技术.
- 在ROMP应用中,控制反应性,特别是寿命和固化速度仍然是一个挑战.
- 额头聚合提供了一个独特的方法来快速处理材料.
研究的目的:
- 调查和比较前环开放转化聚合 (FROMP) 和室温无溶剂ROMP的反应模式.
- 了解抑制剂度和启动器负荷对聚合动学的影响.
- 开发提高树脂容器寿命和正面聚合率的策略.
主要方法:
- 在不同的抑制剂和启动剂度下对FROMP和室温ROMP的比较动力学研究.
- 开发一种评估树脂容器寿命的快速方法.
- 建立一个积极的发起者行为模型.
- 使用修改后的树脂系统直接写入热结构的墨水.
主要成果:
- 与室温ROMP相比,FROMP对抑制剂度的敏感性较低.
- 增加启动器与单体的比率可以在室温下提高树脂的寿命.
- 由于启动剂度和抑制剂解离的增加,高温加速了前端聚合率.
- 更高的启动器负载令人惊地提高了寿命和正面聚合速度,达到比以前报告的速度快五倍以上.
- 这种违反直觉的行为与抑制剂-启动剂的接近以及温度依赖的抑制剂协调/解离有关.
结论:
- FROMP提供了一个可调节的平台来控制聚合动力学.
- 在FROMP中优化启动器加载可以同时提高寿命和治愈速度.
- 了解抑制剂-启动剂相互作用对于最大限度地提高FROMP性能至关重要.
- 这项研究可以通过直接的墨水编写更快地制造出坚固的耐热结构.
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