氢键型水凝胶自修复行为的Monte Carlo模拟

基于氢键型自修复水凝胶的结构特征构建了其横截面的格气模型, 并利用Monte Carlo模拟方法对其自修复行为进行研究. 首先根据自修复过程中的比热峰值确定了氢键的临界联结分数, 然后重点考察了氢键强度、 合作效应以及平均断面间距对其自修复行为的影响. 在此基础上, 进一步研究了氢键型凝胶的动态修复过程, 讨论了相关因素对自修复时间等动态性质的影响. 结果表明, 氢键型凝胶的自修复在本质上归属于一级热力学相变, 且氢键强度是自修复过程中的最关键因素. 同时, 初始断面间距和格子间的合作效应也可显著影响凝胶的自修复行为.

Monte Carlo Simulation on Self-healing Behaviour of Hydrogen-bonded Hydrogel

We present a lattice gas model for the cross sections of a hydrogen bonded（HB） self-healing hydrogel， and then the Monte Carlo method is employed to simulate its self-healing behavior. The peak of the specific heat in the self-healing process is obviously observed， by which the critical association fraction of hydrogen bonds is obtained to determine whether the self-healing can take place. Furthermore， the influences of the HB strength， cooperation effect， and the separation between the cross sections on the self-healing process are investigated. Consequently， the self-healing of the HB hydrogel is identified as the first-order thermodynamic phase transition， as expected. The HB strength plays the key role not only in thermodynamics but also in dynamics of self-healing process.