石墨烯量子点含量对环氧树脂的热,动力,机械和形态特性的影响
Bárbara Schneider1,2, Heitor Luiz Ornaghi2, Francisco Maciel Monticeli3
1Mantova Indústria de Tubos Plásticos Ltd.a., Rua Archimedes Manenti, 574, B. Centenário, Caxias do Sul 950450-175, RS, Brazil.
Polymers
|January 17, 2024
概括
石墨烯量子点 (CQD) 增强的环氧复合材料. 虽然机械性能保持稳定,但CQD显著提高了导热率和玻璃过渡温度,为材料提供了新的可能性.
科学领域:
- 材料科学 材料科学 材料科学
- 聚合物科学 聚合物科学
- 纳米技术纳米技术
背景情况:
- 环氧树脂是广泛使用的聚合物,具有可调节的特性.
- 石墨烯量子点 (CQD) 是增强材料性能的有希望的纳米填充剂.
- 了解CQD环氧复合材料的结构属性关系对于先进的应用至关重要.
研究的目的:
- 研究不同度的石墨烯量子点 (CQD) 对环氧复合材料的热和动态机械性能的影响.
- 为了将CQD负载与导热率,热扩散率,密度,热容量和机械行为相关联.
- 阐明CQD环氧系统中性能变化背后的机制.
主要方法:
- 将不同重量百分比 (0,1,2.5,5重量%) 的CQD纳入环氧基质.
- 热性质的表征 (导电性,扩散性,密度,热容量) 和动态机械热分析 (DMTA).
- 使用显微镜和相关性分析 (皮尔森图) 分析断裂表面形态.
主要成果:
- 在CQD质量负荷,热导率和热扩散率之间观察到高相关性.
- 断裂表面形态从低CQD含量时的异质转变为高负载时的同质.
- 储存模量保持不变,但玻璃状高原延伸与更高的CQD含量显著增加,增强了热稳定性.
- 观察到较低的能量消散和增加的玻璃过渡温度,同时增加了CQD度.
结论:
- CQD可以显著提高环氧矩阵的热性能和热稳定性,而不会对存储模量等机械性能产生负面影响.
- 固态矩阵中没有聚合物桥梁机制,尽管分散和填充剂量很好,但解释了稳定的机械性能.
- 导热性强烈依赖于CQD粒子大小和环氧基质内的分散.
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