Surface modification of polytetrafluoroethylene film by argon cold atmospheric pressure plasmas for enhancing bonding with graphene‐filled polyimide adhesives

Abstract

Significantly enhanced adhesion of polytetrafluoroethylene (PTFE) films to graphene-filled polyimide (PI) adhesives by argon (Ar) cold atmospheric pressure plasmas (CAPPs) at the exposure durations of 72-96 s was undertaken. Poor adhesion of PTFE film to PI adhesive with no bonding (100% delamination) was highly improved to good bonding (100% attachment) for PTFE film treated by Ar CAPPs. Hydrophobic PTFE surface (water contact angle up to 91.1 ) was changed to hydrophilic PTFE surfaces (water contact angle up to 37.4 -66.0 ) with Ar CAPPs treatment by formation of polar chemical bonds such as C-O and C=O. To realize how the chemical bonds of C-O and C=O were produced onto the PTFE surface by Ar CAPPs, the plasma active species of Ar CAPPs were detected by optical emission spectroscopy.