反应诱导的液晶聚糖含芳胺侧枝
Irum Rafique1, Baoliang Liu1, Amir Said1
1Key Laboratory for Special Functional Aggregated Materials of Ministry of Education, School of Chemistry and Chemical Engineering, Shandong University, Jinan, 250100, P. R. China.
Small (Weinheim an der Bergstrasse, Germany)
|October 5, 2023
概括
研究人员通过接种液晶 (LC) p-硫烯-甲胺 (PSTA) 来开发出一种新型的聚糖. 这种增强的材料表现出更好的导热性和稳定的阴性相结构.
科学领域:
- 聚合物科学 聚合物科学
- 材料科学 材料科学 材料科学
- 有机化学 有机化学
背景情况:
- 聚糖是一种高性能耐热聚合物,具有出色的热稳定性和机械性能.
- 提高聚合物的导热性对于电子和热管理中的应用至关重要.
- 结合液晶结构可以影响聚合物形态和性质.
研究的目的:
- 通过结合液晶 (LC) 结构来合成导热的聚糖.
- 为了研究在聚糖基质中LC结构的形成.
- 为了评估修改后的聚糖的热性能和导电性.
主要方法:
- 通过曼尼赫反应合成本佐单体 (pHBA-da).
- 环开放聚合,以获得寡合物佐素 (OBZ─COOH).
- 在OBZ─COOH上将寡合物p-硫烯-甲胺 (PSTA) 移植到OBZ─COOH上以形成OBZ─PSTA共聚物.
- 使用偏振光学显微镜和小角度X射线散射 (SAXS) 进行了表征.
主要成果:
- 在固化过程中,OBZ─PSTA共聚物成功形成了液晶 (LC) 结构,具有鲜花纹理的阴性相.
- LC相形成是由一个化反应诱导的.
- 与OBZ─COOH.相比,OBZ─PSTA的导热率为0.296 W m-1 K-1,比OBZ─COOH.增加了26%.
- OBZ─PSTA 的玻璃过渡温度 (Tg) 为 241 °C,分别为 346 °C 和 362 °C 的 5% 和 10% 的减肥温度 (Td5,Td10).
结论:
- 将PSTA移植到polybenzoxazine上是一种有效的策略,可以创建导热材料.
- 阴性LC相的形成增强了多佐的导热性.
- 由此产生的OBZ─PSTA共聚物显示出需要改进热管理的应用的潜力.
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