3-巯丙基三甲氧基硅烷自组装膜的制备及其摩擦学性能

采用分子自组装技术在羟基化的玻璃基片表面制备了3-巯丙基三甲氧基硅烷单层膜(MPTS-SAM),运用原子力显微镜(AFM)观察了薄膜的表面形貌,使用X射线光电子能谱仪(XPS)分析了薄膜表面典型元素的化学状态,并运用静-动摩擦系数测定仪评价了薄膜的摩擦磨损性能.研究结果表明:在组装初期,硅烷水解产物主要是与基体表面的羟基发生聚合反应,表面出现岛状物;随着组装时间的增加,基体表面的有机硅烷分子之间发生聚合反应,当组装90min后,可以在基体表面形成完整的自组装薄膜.当组装MPTE-SAM后,基片表面的摩擦系数由无膜时的0.85降到了0.19,说明MPTE-SAM可以降低基片的摩擦系数,并且在较低载荷下具有较好的耐磨性能.

Characterization and Tribological Investigation of Self-assembled 3-Mercaptopropyl Trimethoxysilane Deposited on Glass Substrates

Self-assembled monolayer was fabricated on hydroxylated glass substrates by molecular self-assembly process.Atomic force microscope(AFM) and Xray photoelectron spectrometry(XPS) were used to characterize the thin films.Water contact angle measurements indicate that the ratio of MPTS absorbed on silicon substrate increases with increasing time.The chemical states of some typical elements in the MPTS-SAM were analyzed using X-ray photoelectron spectroscopy. The morphology of the MPTS-SAM was observed using an atomic force microscope.The tribological properties of the as-prepared thin films sliding against a steel ball were evaluated on a friction and wear tester.The results show that the MPTS-SAM is prepared on the glass slide at a film-formation duration of 90min,the corresponding MPTS-SAM shows almost no change in the water contact angle,which indicates that the self-assembly process of the MPTS monolayer is completed in 90min.Moreover,the MPTS-SAM has good friction-reducing and antiwear ability as it slides against the steel counterpart at a small load.The tribological experiment shows that the friction coefficient of glass substrate reduces from 0.85 to 0.19 after the formation of MPTSSAM on its surface.