可加工的二元佐胺混合物的特性和固化动力学
Yue Tang1, Henry E Symons1, Pierangelo Gobbo1,2
1School of Chemistry, University of Bristol, Cantock's Close, Bristol BS8 1TS, U.K.
概括
这项研究引入了一种新的佐树脂系统,使用基于卡达诺的佐 (CA-a) 和使用基于双甲的佐 (BA-a) 的启动器 (TDA). 由此产生的材料表现出良好的流动性,低的聚合温度,并在固化后具有出色的热和机械性能.
科学领域:
- 聚合物科学 聚合物科学
- 材料化学 材料化学
- 有机合成 有机合成
背景情况:
- 佐素树脂提供优良的热稳定性和机械性能.
- 开发具有改进可加工性和性能的新佐素配方至关重要.
- 卡达诺和双甲是佐合成的常见前体.
研究的目的:
- 使用启动器开发一种新型的氧系统,将卡达诺基氧 (CA-a) 和双甲基氧 (BA-a) 结合起来.
- 为了研究由此产生的聚糖的聚合行为,热性能和机械性能.
- 了解开发的佐素系统的微观结构和固化动力学.
主要方法:
- 基于卡达诺尔的佐素 (CA-a) 和基于双甲的佐素 (BA-a) 的合成和表征.
- 配制一种佐胺混合物,其中3,3'-thiodipropionic acid (TDA) 作为一个启动剂.
- 热分析 (DSC,TGA) 用于确定聚合温度和热分解.
- 机械测试 (存储模块) 和动态机械分析 (DMA) 来评估性能.
主要成果:
- 单质前体混合物表现出极好的流动性和低峰聚合温度 (~200°C).
- 固化的聚糖显示出高热分解温度 (>330°C),玻璃过渡温度为~148°C,存储模量为~2.8 GPa.
- 固化树脂的性能与来自BA-a的聚糖同聚合物相当.
结论:
- CA-a和BA-a与TDA的组合提供了一个有前途的佐胺系统,具有增强的可加工性和强大的热力学性能.
- 这种配方为传统的佐素树脂提供了可行的替代品,可能扩大其应用范围.
- 对微观结构和固化动力学的进一步研究为优化这种新的佐酶系统提供了基础.
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