不同分子量和交联密度对形状记忆聚酰亚胺摩擦学性能的影响机制研究  

Effects of Molecular Weight and Crosslinking Density on the Tribological Properties of Shape Memory Polyimides

作　　者：李霄 杨增辉 段春俭 王廷梅[1] 王齐华[1] 张新瑞[1] LI Xiao;YANG Zenghui;DUAN Chunjian;WANG Tingmei;WANG Qihua;ZHANG Xinrui(State Key Laboratory of Solid Lubrication,Lanzhou Institute of Chemical Physics,Chinese Academy of Sciences,Gansu Lanzhou 730000,China;University of Chinese Academy of Sciences,Beijing 100049,China)

机构地区：[1]中国科学院兰州化学物理研究所固体润滑国家重点实验室,甘肃兰州730000 [2]中国科学院大学,北京100049

出　　处：《摩擦学学报》2019年第5期547-555,共9页Tribology

基　　金：国家自然科学基金项目(51673205,51875549);“青年创新促进会”人才培养项目(2018457);中科院前沿科学重点研究项目(QYZDJ-SSW-SLH056)资助~~

摘　　要：近年来由于形状记忆聚合物(SMPs)对热、光、磁和电等外界刺激的自主响应能力,其作为智能润滑材料引起广泛的关注.本研究中以3,3’,4,4’-联苯四甲酸二酐(BPDA)、4,4’-二氨基联苯醚(ODA)和三聚氰胺为前驱体,制备了一系列不同分子量(Mn)的热塑性(TPIs)和不同交联密度(d)的热固性(CPIs)形状记忆聚酰亚胺,并采用球盘式往复摩擦试验机表征材料的摩擦学性能.结果表明:两类聚合物不仅具有不同的磨损机制,且随着分子量Mn的增加和交联剂的引入,材料的摩擦系数和体积磨损率显著降低;此外,摩擦过程中局部摩擦热诱发线性聚酰亚胺的局部形状记忆效应,从而在一定程度上增加摩擦系数和磨损率,但热固性聚酰亚胺受材料形状记忆效应的影响相对较小.In recent years,owing to the self-responsive ability of shape memory polymers(SMPs)towards thermal,optical,magnetic,electrical and other external stimulus,this smart material has attracted more and more attention in the self-lubricating materials field.In this study,3,3′,4,4′-biphenyl tetracarboxylic acid dianhydride(BPDA),4,4′-diamino diphenyl ether(ODA)and melamine were used as precursor to prepare a series of thermoplastic polyimides(TPIs)with different molecular weights(Mn)and thermoset polyimide(CPIs)with different crosslinking densities(d).Moreover,dry sliding tests were performed on a ball-on-disc reciprocating wear tester to characterize the tribological performance of materials.The results show different friction and wear mechanisms for the two kinds of polymers.And with the increase of molecular weight Mn and the introduction of crosslinking agent,a significantly decrease were exhibited in the friction coefficient and volume wear rate of materials.In addition,local friction heat in the process of friction induced the local shape memory effect of linear polyimides,which reduced the coefficient of friction and wear rate to a certain extent.However,the shape memory effect on thermoset polyimides was insignificant.

关 键 词：聚酰亚胺 形状记忆 分子量 交联度 摩擦磨损 

分 类 号：TH117.3[机械工程—机械设计及理论]