在稀释溶液中环聚合物的内在粘度和介电松
1Department of Chemistry, University of Delhi, Delhi 110007, India.
The Journal of chemical physics
|October 23, 2023
概括
环聚合物由于其封闭结构,与线性聚合物相比,具有独特的特性. 这项研究研究了它们的粘度和介电松,发现与聚烯的实验数据有很好的一致性.
科学领域:
- 聚合物物理 聚合物物理
- 理论化学 理论化学
- 材料科学 材料科学 材料科学
背景情况:
- 环聚合物从根本上不同于线性聚合物,原因是缺乏链末.
- 了解这些差异对于聚合物科学和材料应用至关重要.
研究的目的:
- 研究环聚合物的内在粘度,复杂粘度和介电松.
- 将这些特性与线性聚合物进行比较,考虑排除体积相互作用 (EVIs) 和水力动力相互作用 (HIs).
主要方法:
- 利用优化的Rouse-Zimm理论进行理论分析.
- 纳入距离依赖的排除体积相互作用从弗洛里的平均场理论.
- 使用预平均的奥西恩张量估计水力动力相互作用.
主要成果:
- 对于线性和环形聚合物,有或没有EVI,内在粘度随环形大小单调地增加.
- 理论预测显示出与各种分子量和溶剂的实验性聚乙烯数据的良好一致.
- 带有EVI的环聚合物的碎形尺寸处于随机步行和自我避开步行模型之间;介电松表现出普遍的缩放和结构依赖的行为.
结论:
- 优化的Rouse-Zimm理论准确地描述了环聚合物的行为.
- 排除的体积相互作用显著影响环聚合物尺寸,特别是对于较大的环.
- 介电松提供了对环聚合物的结构依赖动态的洞察.
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