具有双温度反应的化玻璃弹性体
Marc Guerre1, Christian Taplan1, Renaud Nicolaÿ2
1Polymer Chemistry Research Group and Laboratory for Organic Synthesis, Department of Organic and Macromolecular Chemistry , Ghent University , Krijgslaan 281 S4-bis , Ghent B-9000 , Belgium.
Journal of the American Chemical Society
|September 20, 2018
概括
这项研究引入了一种新的无催化剂玻璃化物系统,由于竞争的债券交换机制,其具有双重粘度. 这一突破为先进的材料加工提供了对玻璃体的新控制.
科学领域:
- 聚合物化学
- 材料科学
- 病理学
背景情况:
- 玻璃聚合物是具有交叉连接网络的高级聚合物,在加热时表现出类似液体的行为.
- 它们的流量特性通常由催化剂和添加剂控制,这些催化剂和添加剂会影响债券交换反应.
- 现有的玻璃体系统通常需要外部剂来调节其质特性.
研究的目的:
- 开发一种无催化剂的玻璃制剂系统,具有可调节的质特性.
- 调查不同温度依赖的多种债券交换机制的共存.
- 在没有外部添加剂的玻璃材料中实现双粘度.
主要方法:
- 从两个简单的组件构建一个玻璃制剂系统.
- 分析竞争的债券交换机制及其激活能量 (60对130-170kJ/mol).
- 在温度范围内对双粘度配置的描述.
主要成果:
- 一个没有催化剂的玻璃制剂系统成功地准备好了.
- 确定了两个具有明显温度依赖性的竞争性债券交换机制.
- 观察到异常的双粘度特征,其特征是粘度逐渐下降,然后急剧下降.
- 这种行为在化和非化玻璃弹性体中得到证实.
结论:
- 一种无催化剂的新型玻璃体系统表现出独特的双粘度行为,由温度依赖的键交换机制驱动.
- 这些发现为量身定制的加工应用提供了精确控制玻璃物流的新策略.
- 这种方法有助于设计具有可调节流量特性的高性能聚合物材料.
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