HU Weiwei 1,2 , ZHAO Wenjie1,3, CAO Huijun1, ZENG Zhixiang1, ZHANG Xin1,3, WU Xuedong1*
(1.Ningbo Key Laboratory of Marine Protection Materials, Ningbo Institute of Material Technology & Engineering, Chinese Academy of Sciences, Ningbo 315201, China; 2. Graduate University of Chinese Academy of Sciences, Beijing 100049, China; 3. State Key Laboratory of Solid Lubrication, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou 730000, China)
Abstract: Dopamine is used to modify the inert surface of ultra high molecular weight polyethylene (UHMWPE) powders for its oxidative self-polymerical property. The compatibility between powders and epoxy resin is enhanced and then epoxy coatings with excellent anti-wear and tough properties are prepared. Scanning electron microscope, X-ray photoelectron spectroscopy and infrared spectroscopy are utilized to characterize the surface morphology and the chemical states of the dopamine-modified powders. Tribological tester is utilized to evaluate the friction coefficient and wear rate of the epoxy coatings. Results show that a polydopamine layer which is full of polar groups adhered on the surface of dopamine-modified powders. This layer reacts with the epoxy resin and this enhances the compatibility. The ratios of O to C and N to C on the surface of dopamine-modified powders first increase with the modification time and then reach a maximum at a modification time of 5 h. The impact-resistance performance of epoxy coating is enhanced by increasing the dopamine-modified powder content from 6.7% to 20%. In addition, friction coefficient and wear rate are also decreased. The comprehensive performance of epoxy coating with dopamine-modified powders is better than the one with unmodified powders.
Key words: UHMWPE; dopamine; surface modification; epoxy resin; tribological properties; toughness
E-mail: xdwu@nimte.ac.cn
Tribology, Vol. 32, Issue 5, 2012, 435~443
