Improvement of Load Bearing Capacity of Nanoscale Superlow Friction by Synthesized Fluorinated Surfactant Micelles
journal contributionposted on 22.01.2018, 00:00 by Jinjin Li, Zengpei Dou, Yuhong Liu, Jianbin Luo, Jinxin Xiao
Although surfactant micelles usually exhibit superlow friction at the nanoscale due to the formation of the hydration layer, the load-bearing capacity (LBC) is limited. In this study, the friction behaviors of two different surfactant micelles (fluorinated and hydrocarbon surfactants, denoted as F-surfactant and H-surfactant) were compared, with the results showing that both can achieve superlow friction (μ = 0.001–0.002) when the self-assembled micelle layers on the two surfaces were not ruptured. Although the two different surfactant micelles have the similar friction behaviors, the LBC of superlow friction for the F-surfactant is 2.5 times larger than that for the H-surfactant. The mechanisms of the superlow friction and the reasons for different LBC were investigated using an atomic force microscopy. The superlow friction can be attributed to the formation of hydration layer on the surfactant headgroups, whereas the higher LBC for F-surfactant originates from the fatness of its carbon chain, which produces the larger hydrophobic attraction and meanwhile increases the stiffness of the micelle layer.