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选择的聚合物在环素中的可溶性:使用三种不同的分子动力学模拟方法计算的Flory-Huggins相互作用参数之间的比较

Gabriel P Costa¹, Stanislav R Stoyanov², Qi Liu¹

¹Department of Chemical and Materials Engineering, University of Alberta, Edmonton, Alberta T6G 2G6, Canada. phillip.choi@uregina.ca.

Physical chemistry chemical physics : PCCP

|November 26, 2024

概括

用于聚合物可溶性预测的分子动力学模拟表明,溶解方法的度提供了最准确的Flory-Huggins相互作用参数 (χ) 以合理的计算成本. 对于非极性聚合物来说,吉布斯自由能量方法更密集,更不准确.

科学领域:

计算化学计算化学
聚合物科学聚合物科学
材料科学材料科学材料科学

背景情况:

准确预测聚合物溶解度对于实际应用至关重要.
弗洛里-哈金斯相互作用参数 (χ) 是可溶性预测的关键指标.
分子动力学 (MD) 模拟是计算 χ 的强大工具.

研究的目的:

评估三种MD模拟策略,用于计算弗洛里-哈金斯相互作用参数 (χ).
为了比较不同方法的精度和计算效率来确定聚合物可溶性.
用MD模拟来分析溶液中的聚合物形状变化.

主要方法:

使用三种MD模拟策略计算 χ:希尔德布兰德溶解度参数,溶解的度和Gibbs自由能量.
研究了各种疏水性和疏水性聚合物的二元溶液 (例如,聚乙烯,聚乙烯,PEO,聚烯胺) 在环素中.
进行了形状分析,包括旋转半径 (Rg) 和溶剂可访问的表面积 (SASA).

主要成果:

溶解度参数方法预测了趋势,但与实验值有显著的偏差.
溶解的度产生了最准确的 χ 值,具有合理的计算需求,特别是碳化合物聚合物.
对非极性聚合物来说,Gibbs自由溶解能量在计算上是密集的,并且高估了 χ,但在精度上没有明显的改进.

结论:

溶解方法的度是最有效的MD策略,用于准确和高效的计算 χ.
在环素中观察到聚合物形状变化 (崩),极性聚合物表现出更明显的效应.
选择MD模拟策略显著影响确定聚合物可溶性的准确性和资源要求.

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