通过准弹性中子散射和分子动力学模拟研究溶液中的聚素的分子动力学:聚合物上的环滑动
Yusuke Yasuda1, Yuta Hidaka1, Koichi Mayumi1
1Department of Advanced Materials Science, School of Frontier Sciences , The University of Tokyo , 5-1-5 Kashiwa-noha , Kashiwa , Chiba 277-8561 , Japan.
Journal of the American Chemical Society
|May 16, 2019
概括
我们使用中子散射和模拟研究了聚氨酸 (PR) 的动态. 我们量化了循环素 (CD) 沿着聚乙醇 (PEG) 链的滑动运动,发现它由于分子相互作用而变慢.
科学领域:
- 聚合物科学
- 材料化学
- 分子动力学
背景情况:
- 多聚素 (PRs) 是具有潜在应用的超分子结构.
- 了解PR的分子动力学对于它们的设计和功能至关重要.
- 关键组件包括在聚乙烯糖 (PEG) 链上螺纹连接的循环素 (CD).
研究的目的:
- 调查溶液中的聚素 (PR) 的分子动力学.
- 量化循环素 (CDs) 在聚乙烯糖醇 (PEG) 链上的转换和滑动运动.
- 开发一种用于预测公关中的滑动动态的模型.
主要方法:
- 准弹性中子散射 (QENS) 的测量.
- 全原子分子动力学 (MD) 模拟.
- 对转移和滑动运动的扩散系数的分析.
主要成果:
- QENS和MD模拟提供了对扩散系数的定量一致性.
- 成功观察并量化了CDs沿着PEG链的滑动.
- 由于分子相互作用,滑动扩散系数比转化扩散低约6倍.
结论:
- CDs和PEG之间的分子相互作用会形成能量屏障,减缓滑动.
- 一个简单的方程结合了爱因斯坦-斯托克斯和跳跃扩散模型,描述了PR滑动动力学.
- 这项研究提供了一种通过分子设计控制 PR 滑动的策略.
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