Preparation of poly (N-isopropylacrylamide) brush bonded on silicon substrate and its water-based lubricating property  

作　　者：LIU YuHong XIAO YuQi LUO JianBin 

机构地区：[1]State Key Laboratory of Tribology,Tsinghua University,Beijing 100084,China

出　　处：《Science China(Technological Sciences)》2012年第12期3352-3358,共7页中国科学（技术科学英文版）

基　　金：supported by the National Natural Science Foundation of China (Grant Nos. 50805086 and 50730007);the Foundation for Innovative Research Groups of the National Natural Science Foundation of China (Grant No. 51021064)

摘　　要：The poly (N-isopropylacrylamide) brush was covalently bonded on an initiator-coated silicon wafer via surface-initiated atom transfer radical polymerization. The polymer brush was (76.2±0.1) nm in thickness (by ellipsometer) with a grafting density of ca. 0.27 chains/nm 2 . The tribological properties of the poly (N-isopropylacrylamide) brush were investigated by means of ball-on-disk tests in a rotational mode under water lubrication for tribological application. The experimental results exhibited a low friction coefficient of ca. 0.03. The excellent lubrication property of the brush was due to its amide groups in the polymer chains. It was supposed that the good lubrication property of the brush was attributed to the cross-linked polymer network formed by the hydrogen bond association of N-H…O==C and the water molecular layer adsorbed by the terminal amide groups in the brush. The poly (N-isopropylacrylamide) solution also exhibits a lubrication property due to physical adsorption of the polymer chains.

关 键 词：poly（N-isopropylacrylamide） brush surface-initiated atom transfer radical polymerization water-based lubricatingproperties 

分 类 号：O633.22[理学—高分子化学] TH133.3[理学—化学]