Preparation and tribological properties of self-assembled polystyrene film

A method for chemically attaching ultra-thin polymer films through the self-assembly of end silane terminated polymer is provided in this article. End trimethoxysilane functionalized polystyrene (PSt) was first prepared through radical chain transfer reaction and characterized by FTIR, H-1-NMR and gel permeation chromatography (GPC) The coincidence of the calculated molecular weight of the prepared end silane terminated PSt from both GPC and NMR proved high end functionalized ratio. The self-assembly behavior on silicon wafers of the obtained polymer was studied by measuring the contact angle, film thickness. The chemical characteristics and the nano scale morphology of the film were investigated with FTIR, X-ray photoelectro spectroscopy (XPS) atomic force microscopy (AFM) It was found that homogeneous and complete polymer film could be formed only when the polymer concentration exceeded 1 mg/mL. The root mean roughness of the complete polymer was below I rim. The tribological properties of the prepared PSt film were investigated using a static-dynarnic friction precision measurement apparatus. The friction coefficient of self-assembled PSt film against steel ball at a load of 0.5 N was in the range of 0.08similar to0.1 which was much lower than that for bare silicon wafers in the same experiment conditions (0.7similar to0.8). Self assembled PSt modified silicon wafers exhibited excellent friction reduction and anti-wear behavior comparing with their bare counterparts. According to this investigation, self-assembled polymer films have the prospect for friction reduction and wear resistance.