Synergistic effect of sharkskin-inspired morphologies and surface chemistry on regulating stick-slip friction

The tribological behaviors of soft materials are closely related to their surface chemistry and morphology. Thus, this study investigates the effects of surface chemistry and morphology on the stick-slip friction of polydimethylsiloxane (PDMS). Air plasma treatment is conducted to modify the surface chemistry, and the bionic shark skin texture is replicated on PDMS. The synergistic effect of the bionic shark skin texture and air plasma treatment on stick-slip friction is evaluated. The results show that air plasma treatment and bionic texture decrease the friction force. Various stick-slip features are observed under different numbers of pendant chains at the contact interfaces, which increase the adhesion force. This study provides fundamental insights into the stick-slip behaviors of other soft materials.