烯酸环氧化物增加循环烯酸单体的应变能量,用于环开转化聚合
Kyle R Sylvester1, Jessa R Zovinka1, Maya L Milrod1
1Department of Chemistry, Wesleyan University, 52 Lawn Ave, Middletown, CT, USA.
Angewandte Chemie (International ed. in English)
|September 25, 2024
概括
这项研究引入了用于环开放元解聚合 (ROMP) 的新型双循环单体,扩大了聚合物的特性超出了传统的norbornene衍生物. 新的单体产生的聚合物具有较低的玻璃过渡温度和易于修改的环氧化基.
科学领域:
- 聚合物化学 聚合物化学
- 有机合成 有机合成
- 材料科学 材料科学 材料科学
背景情况:
- 环开元化聚合 (ROMP) 通常使用应变的norbornene衍生物,限制聚合物性质的多样性.
- 开发新的单体对于扩大ROMP的范围和应用至关重要.
研究的目的:
- 调查用于ROMP的环氧化二烯衍生的新型双环单体.
- 评估由此产生的聚合物的聚合性和特性,重点是循环烯酸与烯酸环氧化物.
主要方法:
- 通过商业dienes的环氧化合成了新的双循环单体.
- 利用密度函数理论 (DFT) 来估计环状应变.
- 使用八个成员 (3,4-COO) 和五个成员 (CPO) 循环烯酸进行了ROMP.
- 聚合物特性,包括玻璃过渡温度 (Tg) 和战术性.
主要成果:
- 确定了 (3,4-COO) 和CPO作为有效的ROMP单体,CPO显示出高聚合性.
- 聚合物表现出较低的玻璃过渡温度,与传统的聚合物不同.
- 聚3,4-COO) 显示了高的立体和区域规律性;聚CPO) 显示了低的规律性.
- 这两种聚合物都允许通过环氧化环开放进行易于的聚合后修饰.
结论:
- 新的双循环单体,特别是CPO,为ROMP提供了一个多功能平台.
- 这些单体能够合成具有调节性质和低Tg的功能性聚合物.
- 由于其高环氧化物密度和反应性,CPO是创建多种功能材料的有希望的单体.
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