对具有溶剂反应的机械互锁环聚合物的单分子分析以及从粗粒度模拟中纳米封闭的影响
Diego Becerra1, Alexander R Klotz2, Lisa M Hall1
1William G. Lowrie Department of Chemical and Biomolecular Engineering, The Ohio State University, Columbus, Ohio 43210, USA.
The Journal of chemical physics
|March 21, 2024
概括
我们模拟了机械互锁的环聚合物,发现拓,而不是环数,决定了结构. 限制影响了聚合物形状和过渡,提供了对动态细胞DNA (kDNA) 网络的见解.
科学领域:
- 聚合物物理 聚合物物理
- 生物物理学的生物物理.
- 计算化学计算化学
背景情况:
- 机械互锁的聚合物表现出复杂的形状.
- 动态细胞DNA (kDNA) 形成具有独特拓性质的小圆网络.
- 了解聚合物在封闭状态下的行为对于各种应用至关重要.
研究的目的:
- 模拟和分析机械互锁半柔性环聚合物的结构性质.
- 研究拓链接和纳米封锁对聚合物结构的影响.
- 将模拟结果与kDNA网络的实验观测进行比较.
主要方法:
- 使用粗粒度的分子动力学模拟.
- 研究了两环和三环聚合物系统.
- 模拟了不同的溶剂质量和不同程度的限制.
主要成果:
- 在良好的溶剂中,增加交叉点限制了双环系统,减少了尺寸.
- 三环系统显示尺寸相似性,无论交叉号码.
- 不利的溶剂诱导了与接触增加的倒塌结构.
- 形态多样性源于拓联系,而不是环数.
- 极端的封闭导致同otropic,扩展形状和转移的崩过渡.
结论:
- 拓连接是机械互锁环聚合物形态学的主要决定因素.
- 纳米封闭显著改变了聚合物构造和相位过渡.
- 模拟提供了对kDNA网络行为的见解,但强调了网络推断中的挑战.
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