亲水、疏水聚合物刷水润滑机制的对比研究  

Comparative Research on Lubricating Mechanism of Surfaces Grafted with Hydrophilic and Hydrophobic Polymer Brushes

作　　者：孙靖东 杨淑燕 吴杨[3] 周峰[3] 郭峰 SUN Jingdong;YANG Shuyan;WU Yang;ZHOU Feng;GUO Feng(School of Mechanical Engineering,Qingdao Technological University,Shandong Qingdao 266520,China;Shandong Laboratory of Yantai Advanced Materials and Green Manufacturing,Shandong Yantai 264006,China;State Key Laboratory of Solid Lubrication,Lanzhou Institute of Chemical Physics,Chinese Academy of Sciences,Gansu Lanzhou 730000,China)

机构地区：[1]青岛理工大学机械与汽车工程学院,山东青岛266520 [2]烟台先进材料与绿色制造山东省实验室,山东烟台264006 [3]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

出　　处：《摩擦学学报（中英文）》2024年第4期519-529,共11页Tribology

基　　金：国家自然科学基金项目(22032006,51775287);中国科学院B类先导科技专项培育项目(XDPB24);烟台先进材料与绿色制造山东省实验室开放课题重点项目(GM2021A02)资助。

摘　　要：通过表面接枝聚合技术在摩擦副表面(陶瓷球-玻璃盘)分别生长亲、疏水型2种聚合物刷:聚甲基丙烯酸-3-磺酸丙酯钾盐(PSPMA)和聚甲基丙烯酸月桂酯(PLMA),成功构筑了润湿性不同的2种浸润表面,利用球-盘式光干涉薄膜测量装置研究了2种表面在水环境中的液膜厚度和摩擦力变化,结果表明2种表面呈现出不同的减摩效果:PLMA表面的摩擦力稳定且随速度变化较小,推测这与其较低的表面自由能和低玻璃化温度有关;PSPMA表面的摩擦系数波动较大且滑滚比和卷吸速度对其影响较大,这可能与聚合物刷发生高度水化而在接触表面形成了1层具有法向承载能力的水合层有关.亲水的PSPMA表面形成的水膜膜厚要远远高于疏水的PLMA表面水膜.高速滑动条件下,在流体动压效应和水合作用共同耦合作用使得PSPMA表面呈现出了润滑增强作用,从而获得了较高的膜厚和较低的摩擦系数.研究表明聚合物刷的水合效应对于获取优异的润滑性能是至关重要的,这对于理解水基润滑的机理和指导水润滑材料的设计具有较为重要的意义.A couple of polymer brushes were grafted on the subsurface of ceramic ball and glass disk by surface-initiated radical polymerization technique,which were poly(propyl methacrylate-3-sulfonate)potassium salt with hydrophilic functional groups poly(propyl methacrylate-3-sulfonate)potassium salt with hydrophobic functional groups,hereinafter abbreviated as PSPMA and PLMA respectively,and thus two counterpart surfaces with different wettability were successfully constructed,the film thickness and friction were measured by homemade film measurement device based on interference technology.The measurement results demonstrated that the two surfaces showed different antifriction effects.For PLMA,the friction coefficient was very low and stable,it was speculated that it was related to the lower surface free energy and the lower glass transition temperature.The friction coefficient of PSPMA fluctuates greatly and was highly affected by the slip-roll ratio and the entrainment speed,which may be related to the formation of a hydrated layer with normal bearing capacity on the contact surface due to high hydration.The thickness of water film formed on the surface of grafted PSPMA was much higher than that of PLMA,which can be attributed to their different degree of hydration,and it was found that PSPMA showed a lubrication enhancement effect under the coupling action of hydrodynamic pressure and hydration,thus obtaining a higher film thickness.The thickness of the water film formed on the surface of grafted PSPMA was much higher than that of PLMA,which can be attributed to the fact that the hydration degree of PSPMA brush was much higher than that of PLMA.Under the coupling effect of hydrodynamic and hydration,PSPMA presented a lubrication enhancement effect,thus obtaining a higher film thickness.The research showed that the hydration effect of polymer brush was crucial for obtaining excellent lubrication performance,which was of great significance for understanding the mechanism of water-based lubrication mechanism and guiding

关 键 词：聚合物刷 水合效应 表面润湿性 膜厚 流体动压效应 

分 类 号：TH117.2[机械工程—机械设计及理论]