Adhesion and water lubrication of silastic micro-fiber arrays with monolayer surface modification

This study describes different surface energy monolayer modified Silastic micro-fiber Arrays (PDMS Arrays) to enhance the adhesion and water lubrication performances of PDMS Arrays. A multistep fabrication process consisting of electrochemical etching silicon wafers, cast PDMS Arrays, grafts poly(methylhydrosiloxane) (PMHS) onto PDMS Arrays, and modified the PDMS Arrays surface with Poly(ethylene glycol) methyl ether methacrylate(PEG-MA) and Poly(tetrafluoroethylene acrylate) (PTFE-PA), an intrinsically adhesive synthetic polymer. Attenuated total reflectance-fourier transform infrared (ATR-FTIR) spectroscopy was used to monitor the entire process. Results showed that Si-H peak disappeared and two characteristic peaks appeared means PEG-MA and PTFE-PA successful graft to PDMS Arrays Surface. Results from cohesive tests showed that the adhesion of PEG-MA-g-PDMS Arrays enhance, but the adhesion of PTFE-PA-g-PDMS Arrays decrease. Results from water lubrication tests showed that the hydrophilicity of PEG-MA-g-PDMS Arrays increase, contact angle from 122.5° to 94.2°, but PTFE-PA-g-PDMS Arrays contact angle is increased to 129.1°.