用分子动态模拟与随机分布的硫链交联的聚丁的玻璃过渡温度和热导率
Tannaz Alamfard1, Tommy Lorenz1, Cornelia Breitkopf1
1Chair of Thermodynamics, Institute of Power Engineering, Faculty of Mechanical Engineering, Technical University Dresden, 01069 Dresden, Germany.
Polymers
|February 10, 2024
概括
这项研究调查了硫链长度如何影响聚丁二烯.
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
- 计算化学计算化学
背景情况:
- 聚乙烯交叉连接会影响材料的性能.
- 硫链长度是交叉链接的一个关键参数.
- 了解热性质对于材料应用至关重要.
研究的目的:
- 研究硫链长度对聚butadiene 的导热率和玻璃过渡温度的影响.
- 分析交联密度,摩尔质量和热性质之间的关系.
- 探索温度依赖的导热性行为.
主要方法:
- 平衡分子动力学 (EMD) 模拟.
- 格林-库博方法用于计算导热率.
- 硫链长度 (S1-S8) 和摩尔质量的系统变化.
主要成果:
- 对于所有模型来说,随着温度的增加,导热率都会下降.
- 增加硫链长度和摩尔质量提高了导热率 (在不断交叉连接的情况下).
- 玻璃过渡温度和密度随着硫链的长度和摩尔质量的增加而增加.
结论:
- 硫链长度和摩尔质量是控制聚丁热导电性和玻璃过渡温度的关键因素.
- 分子动力学模拟提供了对结构-属性关系的见解.
- 定制交叉连接参数可以调整材料的热性能.
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