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惯性和活性:半柔性,自我避开的聚合物中的螺旋过渡
Chitrak Karan1,2, Abhishek Chaudhuri3, Debasish Chaudhuri1,2
1Institute of Physics, Sachivalaya Marg, Bhubaneswar 751005, India. chitrak.k@iopb.res.in.
Soft matter
|July 25, 2024
概括
这项研究揭示了聚合物的动态回流转变,随着活性增加,聚合物从开放链转向旋转螺旋. 在更高的活动水平上,惯性在破坏这些螺旋结构的稳定性方面发挥着关键作用.
科学领域:
- 软物质物理学 软物质物理学
- 聚合物动力学 聚合物动力学
- 统计力学 统计力学
背景情况:
- 自避免的聚合物表现出由活动和惯性影响的复杂行为.
- 了解不同聚合物构造之间的过渡对于材料科学至关重要.
研究的目的:
- 研究2D,触角活性,半柔性聚合物中的动态回流转变.
- 在活动-惯性平面中映射聚合物结构的相位图.
- 分析活性和惯性对聚合物大小,形状和平衡差异的影响.
主要方法:
- 利用转数的概率分布来确定结构稳定性.
- 分析了端到端距离分布和旋转电位子半径的尺寸和形状.
- 计算Kullback-Leibler分歧以量化偏离平衡分布的偏差.
主要成果:
- 确定了从移动的开放链到旋转的状螺旋的转变,活动越来越多.
- 低活动时的螺旋形成是扭矩平衡和惯性独立的;较高的活动会导致惯性不稳定.
- 库尔巴克-莱布勒分歧显示了与活动的非单调关系,在紧的螺旋上达到顶峰,并且随着惯性增加而减少.
结论:
- 该研究提出了在不同活性和惯性下聚合物行为的详细相位图.
- 惯性在较高的活动水平上显著影响螺旋不稳定,这种现象在过度缩的极限中不存在.
- 聚合物的偏离平衡与其紧性和旋转持久性有关,由惯性调节.
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