P ((MMA-co-MAA) /纤维素纳米纤维复合材料:键对分子移动性的影响
Valentina Cavallo1, Aurélien Roggero2, Alberto Fina3
1Université de Lyon, CNRS, Université Claude Bernard Lyon 1, INSA Lyon, Université Jean Monnet, UMR 5223, Ingénierie des Matériaux Polymères, CEDEX, F-69621 Villeurbanne, France; Dipartimento di Scienza Applicata e Tecnologia, Politecnico di Torino, V.le Teresa Michel, 5, 15121 Alessandria, Italy.
Carbohydrate polymers
|September 8, 2024
概括
纤维素纳米纤维 (CNFs) 在PMMA-co-MAA纳米复合材料中减缓了聚合物放松. 由于CNF与聚合物矩阵之间的键,出现了新的放松.
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:
- 聚合物纳米复合材料通过填充物集成提供增强的性能.
- 了解宏分子流动性对于设计先进材料至关重要.
- 键在聚合物 - 矩阵相互作用中起着重要作用.
研究的目的:
- 为了研究纤维素纳米纤维 (CNFs) /多甲基甲酸-co-甲酸) (PMMA-co-MAA) 纳米复合材料中的宏分子运动性.
- 阐明结和CNF添加对分子动态的影响.
- 描述纳米复合材料系统中的放松过程.
主要方法:
- 动力机械分析 (DMA) 用于机械放松.
- 宽带介电光谱 (BDS) 用于介电放松.
- 对玻璃过渡温度 (Tg) 的差分扫描热量计 (DSC).
主要成果:
- 尽管Tg值相似,但CNF显著减缓了α-放松过程.
- β-放松激活能量保持不变,但由于CNF-矩阵相互作用,出现了新的β'-放松.
- 在纳米复合材料中,γ-放松激活能量增加了45%,这归因于CNF阻碍甲基运动.
结论:
- CNF 作为物理交叉连接器,限制了聚合物链的移动性.
- 在CNF表面基组和矩阵基组之间的键相互作用是关键的.
- 这项研究提供了关于CNF-聚合物纳米复合物的结构-性质关系的见解.
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