稀溶液中大幅拉伸高分子单链的弛豫动力学  

Relaxation Dynamics of a Highly Stretched Single Polymer Chain in a Dilute Solution

作　　者：姚宁[1] 王海军[1,2,3] 李江涛[1] 顾芳[1] 廖琦[4] YAO Ning;WANG Haijun;LI Jiangtao;GU Fang;LIAO Qi(College of Chemistry and Materials Science,Hebei University,Baoding 071002,China;Chemical Biology Key Laboratory of Hebei Province,Hebei University,Baoding 071002,China;Key Laboratory of Medicinal Chemistry and Molecular Diagnosis,Ministry of Education,Hebei University,Baoding 071002,China;Institute of Chemistry,Chinese Academy of Sciences,Beijing 100190,China)

机构地区：[1]河北大学化学与材料科学学院,保定071002 [2]河北大学河北省化学生物学重点实验室,保定071002 [3]河北大学药物化学与分子诊断教育部重点实验室,保定071002 [4]中国科学院北京化学研究所,北京100190

出　　处：《高等学校化学学报》2024年第4期134-141,共8页Chemical Journal of Chinese Universities

基　　金：国家自然科学基金(批准号:21973103);河北省中央引导地方科技发展资金(批准号:236Z7601G);河北省自然科学基金(批准号:B2022201050,B2023201108);河北大学多学科交叉研究项目(批准号:DXK202112)资助。

摘　　要：针对大幅拉伸的高分子单链在Θ溶剂和良溶剂中的弛豫过程,分别通过解析理论和分子动力学模拟方法研究了弛豫动力学.对比研究发现,相对于研究高分子链在平衡态下的弛豫动力学(利用有关物理量的自关联函数),本文的非平衡态方法可以明确地揭示弛豫时间与简正模式之间标度行为的动态演化.结果表明,相关的物理量在弛豫初期均受到非平衡态的影响,而在较长时间后,高分子链的弛豫动力学则与平衡态下的结果相吻合;在高分子链的最长弛豫时间与链长的标度关系方面,平衡态和非平衡态两种方法的研究结果也一致.研究结果表明,高分子链在非平衡态下的短时和长时弛豫动力学可以更加细致地阐明弛豫全过程,给出更加丰富的结构-特征关系,从而为深入探讨高分子链的非平衡弛豫提供可借鉴的线索.For the relaxation of a highly stretched single polymer chain in dilute solutions of various solvent quali⁃ties,the relaxation dynamics was investigated through the methods of analytical theory and molecular dynamics(MD)simulation.To facilitate the comparison,the equilibrium and non-equilibrium routes were employed in the simula⁃tions,where the equilibrium route is performed by using the self-correlation function of related physical quantities.The reason for using the non-equilibrium route is that it is directly related to many practical processes,and the dynamic evolution of the scaling behavior between the relaxation time and normal modes can be present clearly.Consequently,it is found that at the initial stage of relaxation,some physical quantities would be influenced by the non-equilibrium initial state of the polymer chain, while after a certain time, the relaxation dynamics is consistent with that predicted the equilibrium state. Meanwhile, the two routes showed the same scaling behavior between the longest relaxation time and chain length. The non-equilibrium route is therefore helpful to investigate the whole relaxation process of a polymer chain, thereby giving more information of structure-property. It is expected that such an effort can provide some useful clues to pertinent topics.

关 键 词：高分子单链 弛豫动力学 简正模式 弛豫时间 

分 类 号：O631[理学—高分子化学]