添加剂尺寸在交联聚合物的细分动力学和机械性质中的作用
Xiangrui Zheng1, Lan Xu2, Jack F Douglas3
1Department of Mechanics, School of Aerospace Engineering, Huazhong University of Science and Technology, Wuhan, 430074, China.
Nanoscale
|August 27, 2024
概括
热聚合物中添加剂尺寸的变化会产生化学异质性,并影响材料的性能. 较小的添加分段导致聚合,通过缩放规律影响机械和动态行为.
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
- 化学工程是化学工程的重要组成部分.
背景情况:
- 耐热材料利用添加剂来修改化学物理性质.
- 增材集成可以导致组合异质,影响材料性能.
- 了解添加效应对于设计先进的聚合物复合材料至关重要.
研究的目的:
- 为了研究添加剂大小对耐热聚合物特性的影响.
- 探索添加剂聚合和材料异质性之间的关系.
- 建立基于增量尺寸的动态和机械性质的缩放规律.
主要方法:
- 使用粗粒度 (CG) 模型进行热固化研究.
- 变化聚合物添加剂细分的尺寸相对于热固态矩阵.
- 通过德拜-沃勒因子 (iu^2) 估计局部分子刚度.
主要成果:
- 添加剂聚合和化学异质性观察到当添加剂细分显著较小时.
- 在局部分子度的空间分布中显示的异质性的明显证据.
- 动态和机械性质的非单调变化随着添加物尺寸的减少.
结论:
- 添加剂尺寸在耐热聚合物动力学和力学中起着复杂的作用.
- 结构放松时间和模块表现出Debye-Waller因子的缩放规律.
- 这些发现提高了对交联聚合物复合材料中玻璃形成的理解.
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