散射粒子动力学模拟用于热固体/热塑性混合物的反应诱导相分离
Yoshiaki Kawagoe1, Gota Kikugawa2, Keiichi Shirasu3
1Department of Aerospace Engineering, Tohoku University, 6-6-01, Aoba, Aramaki, Aoba-ku, Sendai, Miyagi 980-8579, Japan.
The journal of physical chemistry. B
|February 19, 2024
概括
这项研究模拟了使用散射粒子动力学 (DPD) 的热树脂中反应诱导的相分离. 控制形态形成是硬化的关键,模拟显示了应变场效应.
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
- 计算化学的计算化学
背景情况:
- 反应诱导的相分离对于通过加入热塑性添加剂来加固耐热树脂至关重要.
- 控制相隔结构的形态对于定制树脂特性至关重要.
- 了解这种现象需要将化学反应尺度与中等尺度聚合物动力学相结合.
研究的目的:
- 用先进的模拟技术复制反应诱导的相位分离.
- 研究各种因素对相分离形态学的影响.
- 将分子层次的模拟与宏观材料特性 (如固化收缩,刚性和应变分布) 联系起来.
主要方法:
- 将散射粒子动力学 (DPD) 模拟与反应模型相结合以模拟固化.
- 通过ab initio量子化学计算来确定耐热树脂固化性能.
- 校准DPD参数使用全原子分子动力学模拟来进行内在物质性质反射.
主要成果:
- 模拟成功地重现了反应诱导的相分离,反映了材料的内在特性.
- 评估了热塑性度,分子量和固化条件对形态学的影响.
- 确认了模拟与实验趋势的一致性,用于固化收缩和刚性.
- 可视化了局部应变场,由于树脂硬度不同而显示出不均的变形.
结论:
- 这项研究提供了分子层面的理解,即热塑性添加剂如何通过受控相位分离来增强热固性树脂的性.
- 模拟方法允许根据基本的化学和物理原理准确预测材料性能.
- 这种方法促进了先进的聚合物复合材料的合理设计,提高了机械性能.
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