交联度和交联点分布对橡胶力学性能影响的微观机理  

Microscopic Mechanism for the Influence of Crosslinking Degree and Crosslinking Point Distribution on Mechanical Properties of Rubber

作　　者：左俊杰 魏志刚[1] 张泽林 Junjie Zuo;Zhigang Wei;Zelin Zhang(School of Mechanical Engineering,Anhui University of Technology,Ma’anshan 243032,China)

机构地区：[1]安徽工业大学机械工程学院,安徽马鞍山243032

出　　处：《高分子材料科学与工程》2025年第2期97-106,共10页Polymer Materials Science & Engineering

基　　金：安徽省自然科学基金资助项目(2008085MA15);安徽省教育厅高等学校自然科学研究重点项目(023AH051122)。

摘　　要：交联度和交联点分布对橡胶的力学性能有重要影响。文中构建了不同交联度和交联点分布聚异戊二烯橡胶(IR)的分子动力学模型,进行了单轴拉伸和拉伸-回复模拟,通过分析分子链的动态特性参数和拉伸变形情况,探讨了交联度和交联点分布对IR动静态力学性能影响的微观机理。结果表明,在拉伸过程中交联度越高、交联点分布越均匀,材料的刚度越大,黏性对应力的贡献越小。分析发现,在拉伸变形中,分子链的变形和分布不均匀程度增加,分子链相对滑移增大,使材料黏性特性增加。通过增大交联度和交联点分布均匀化程度可以增加分子链受到的约束效应,降低分子链变形的不均匀性,从而减小材料的黏性特征。研究结果对于揭示该类材料变形机理,改进材料力学性能和更好的应用提供了参考。The degree of crosslinking and distribution of crosslinking points have a significant impact on the mechanical properties of rubber.The molecular dynamics models of polyisoprene rubber(IR)with different crosslinking degrees and crosslinking distributions were constructed,and uniaxial tensile and tensile recovery simulations were carried out.By analyzing the dynamic characteristic parameters and tensile deformation of molecular chains,the micro mechanism of the influence of crosslinking degree and crosslinking distribution on the dynamic and static mechanical properties of polyisoprene rubber(IR)was explored.The results show that the higher the crosslinking degree and the more uniform of crosslinking distribution during stretching process are,the greater the stiffness of material is,and the smaller the contribution of viscosity to stress is.Analysis has found that during tensile deformation,the degree of deformation and uneven distribution of molecular chains increases,and the relative slip of molecular chains increases,leading to an increase in the viscosity characteristics of material.By increasing the degree of crosslinking and uniformity of crosslinking distribution,the constraint effect on molecular chains can be increased,and the non-uniformity of molecular chain deformation can be reduced,thereby reducing the viscosity characteristics of material.The results of this study provide a reference for revealing the deformation mechanism of this type of material,improving its mechanical properties,and better application.

关 键 词：橡胶 交联度 交联点分布 分子动力学模拟 微观机理 

分 类 号：TQ330.1[化学工程—橡胶工业]