Reconstruction of fluid Langmuir monolayers under shear forces

✍ Scribed by Vladimir V. Tsukruk; Valery N. Bliznyuk; Dale Visser; John Hazel

• Book ID: 104653812
• Publisher: Springer US
• Year: 1996
• Tongue: English
• Weight: 879 KB
• Volume: 2
• Category: Article
• ISSN: 1023-8883
• DOI: 10.1007/bf00182549

✦ Synopsis

Scanning probe microscopy observations of monolayers of a classical boundary lubricant, stearic acid (STA), reveal long-range dynamics of wear and reconstruction of monomolecular films under the shear forces caused by the sliding tip. In the range of sliding velocities studied, the friction forces behave non-monotonically with a maximum value around 0.2 #m/s. The STA monolayer in a fluid state displays a flow of material from the worn area and its redistribution to form local heterogeneous multilayers. The range of influence of the material removal on the monolayer structure around the worn area is up to 80 #m, or more than an order of magnitude larger than the actual worn area. Surface diffusion of mobile organic material is responsible for the observed long-range spreading of local shear stresses produced in the area of wear. It demonstrates the non-local nature of the stress-induced reconstruction in the fluid monolayers, in contrast with solid monolayers, which show very localized wearing processes.