通过并联ROMP/化进行交叉链接的多聚烯
Caitlin S Sample1, Brenden D Hoehn2, Marc A Hillmyer1
1Department of Chemistry, University of Minnesota, Minneapolis, Minnesota 55455-0431, United States.
ACS macro letters
|March 19, 2024
概括
这项研究引入了一种新的并联环开放元解聚合 (ROMP) 和化方法,用于创建交叉链聚烯. 这一过程增强了聚烯网络的氧化稳定性和机械性能.
科学领域:
- 聚合物化学 聚合物化学
- 材料科学 材料科学 材料科学
- 有机合成 有机合成
背景情况:
- 与热塑性聚烯相比,交联聚烯具有更高的冲击强度,耐磨性和化学/热稳定性.
- 传统方法通常依赖于聚合后交叉链接,这可能是低效的.
- 开发新的合成路径,用于强大的交叉连接的多聚烯网,对于先进的材料应用至关重要.
研究的目的:
- 介绍一种新的并联环开放元解聚合 (ROMP) 和化方法,用于合成交联的多聚烯网络.
- 研究化对这些新型网络的氧化稳定性和机械性能的影响.
- 探索基于循环甲 (COE) - 协同二环二烯 (DCPD) 的网络中的结构-属性关系.
主要方法:
- 通过环开放元解聚合 (ROMP) 合成COE-co-DCPD网络.
- 在现场激活分散的转化催化剂,以后使用气进行化.
- 热转换 (玻璃和转换) 的表征,以确定最佳化温度.
主要成果:
- 富含COE的材料表现出类似聚乙烯的结晶度 (25%) 和点 (Tm = 107 °C) 的高可塑性 (>750%延伸).
- 富含DCPD的材料表现出玻璃状的行为 (Tg = 84 °C) 和更高的刚性 (E = 710 MPa),所有材料都表现出高抗拉性.
- 化显著提高了氧化稳定性,防止在暴露在空气中的不和对应物中观察到的机械降解.
结论:
- 双重ROMP/化方法提供了一种有效的途径,可以产生具有增强性能的交叉链接的多烯网络.
- 化对于改善这些多烯网络的长期氧化稳定性至关重要.
- 开发的材料表现出基于COE/DCPD比率的调节性质,为各种应用提供了潜力.
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