钛金属薄膜上两种短链自组装分子膜的制备与摩擦特性

采用自组装技术在钛金属薄膜上制备了两种分子链长相同、官能团不同的自组装分子膜,并对其进行了不同时间的紫外照射,对钛金属薄膜和自组装分子膜进行了表征和摩擦特性测试,研究了紫外照射、官能团、滑动速度和载荷对自组装分子膜摩擦特性的影响,结果表明:通过紫外照射钛金属薄膜表面羟基化、自组装分子水解及自组装分子缩合可在钛金属薄膜上制备结构致密的自组装分子膜,制备的两种短链自组装分子膜可降低钛金属薄膜的摩擦特性,APS自组装分子膜的摩擦特性优于MPS自组装分子膜的摩擦特性,紫外照射5 min的自组装分子膜表面吸附的有机杂质被蒸发掉,对针尖的黏着力减小,从而导致针尖的变形减小,摩擦力最低,而紫外照射15 min的自组装分子膜致密的网状结构被破坏,减弱了自组装分子膜的润滑效应,两种自组装分子膜的摩擦力随着滑动速度的增加略呈上升趋势,随着载荷的增加略呈下降趋势,但是变化不大.

Preparation and friction properties of two short chain self-assembled monolayers on titanium metal films

Two kinds of self-assembled monolayers (SAMs) with same length of molecule chain and different functional groups are prepared on titanium metal film by self-assembled method and radiated by ultraviolet radiation treatment for different times. The characterization and friction properties measurement of titanium metal film and SAMs are explored. The effects of ultraviolet radiation, functional groups, sliding velocity and load on friction properties of SAMs are investigated. The results show that compact SAMs can be prepared by hydroxylation in titanium film surface with ultraviolet radiation, hydrolysis and condensation of self-assembled molecules. Two kinds of short chain SAMs can reduce friction and the friction properties of APS SAMs is better than MPS SAMs, The friction force of SAMs with 5 min ultraviolet radiation is the lowest because the organic contamination at surface is vaporized which results in decrease of the adhesive force to tip and deformation of tip reduced. Lubrication effects of SAMs with 15 min ultraviolet radiation are weakened because of the destroy of compact net structure of SAMs. The friction forces increase slightly with the increasing of sliding velocity and decrease with the increasing of load, but change not significantly.