温度可转移的粗粒度模型,用于测量聚乳酸的体积特性
1Hunan Provincial Key Laboratory of Fine Ceramics and Powder Materials, School of Materials and Environmental Engineering, Hunan University of Humanities, Science and Technology, Loudi 417000, Hunan, P. R. China.
The journal of physical chemistry. B
|December 28, 2023
概括
一个新的粗粒度模型准确地模拟了聚酸 (PLA) 的散装特性,包括热膨胀和玻璃过渡. 这种模型显示出极好的温度可转移性,用于预测聚合物热力学行为.
科学领域:
- 材料科学 材料科学 材料科学
- 计算化学计算化学
- 聚合物物理 聚合物物理
背景情况:
- 精确模拟聚合物体积特性对于材料设计至关重要.
- 粗粒度 (CG) 模型为大规模的聚合物模拟提供了计算效率.
- 聚酸 (PLA) 是一种广泛使用的可生物降解聚合物,具有重要的工业应用.
研究的目的:
- 开发和验证一种新的粗粒度模型来模拟散装聚酸 (PLA) 的体积特性.
- 调查开发的CG模型的温度可转移性和准确性,用于预测热力学性能.
- 阐明控制PLA中玻璃化过渡的关键分子相互作用.
主要方法:
- 开发一种新的粗粒度 (CG) 模型,其中每个单体由单个珠子表示.
- 对二次体,三次体,四次体应变能量的结合和非结合的CG电位的参数化,以及十次体融密度.
- 分子动力学 (MD) 模拟来复制热膨胀,玻璃过渡,散装模块和构造性质.
- 重缩二面体和非结合电位以恢复玻璃过渡温度 (Tg) 并验证体积系数.
主要成果:
- 开发的CG模型成功地复制了PLA散装的热膨胀和玻璃过渡.
- 优化的CG电位表现出极好的温度可转移性,由Simha-Boyer关系验证.
- 二面扭曲和非结合相互作用被确定为玻璃过渡的关键因素.
- 模拟的散装模块和形状特性与广泛的温度范围内的参考数据保持一致.
结论:
- 新的粗粒模型为模拟PLA体积和热力学特性提供了一种可靠且计算效率高的方法.
- 该模型表现出高精度和温度可转移性,使其适合预测聚合物行为.
- 这种多尺度的方法对模拟超越PLA的各种聚合物具有重大前景.
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