Langmuir-Blodgett膜摩擦分子动力学模拟和机理研究  

Study of friction between hydrocarboxylic acid Langmuir-Blodgett films and its mechanism using molecular dynamics simulation

作　　者：张兆慧[1] 韩奎[1] 李海鹏[1] 唐刚[1] 吴玉喜[1] 王洪涛[1] 白磊[1] 

机构地区：[1]中国矿业大学理学院,徐州221008

出　　处：《物理学报》2008年第5期3160-3165,共6页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:10674177);中国矿业大学科技基金(批准号:2006B025)资助的课题~~

摘　　要：采用分子动力学方法,模拟了在两块石英基板上由脂肪酸(C15H31COOH)组成的单层Langmuir-Blodgett(LB)膜间的摩擦特性,探究了超薄膜在滑动过程中的摩擦和结构机理.得出对于单层LB膜在滑动过程中,在速度小于60m/s时,随着速度的增大,其剪切压增大;在速度大于60m/s时,剪切压随速度的增加而减小.其链的倾斜角随着滑动速度的增加而减小.单层膜内的分子之间以氢键方式形成了较大的分子簇,由此导致了剪切压呈现较长的周期性,但在单层膜之间无氢键形成.Molecular dynamics simulation has been used to study the friction and structure mechanism of Langmuir-Blodgett films of hydrocarboxylic acid （C15 H31 COOH） deposited on the SiO2 substrates at different sliding velocities. The results show that, for a certain monolayer, the shear pressure between the monolayers increases when the sliding speed is below 60 m/s and decreases when the sliding speed exceeds 60 m/s. The molecular tilt angle decreases as the velocity increases. The molecular clusters formed in the monolayers by the hydrogen-bond caused the long shear periods, but there is no hydrogen-bond between the monolayers.

关 键 词：分子动力学模拟 朗缪尔布洛杰特膜 纳米摩擦 氢键 

分 类 号：TB383.2[一般工业技术—材料科学与工程]