Autohesion of plasma treated semi-crystalline PEEK: Comparative study of argon, nitrogen and oxygen treatments

▶ In this study, the self-bonding strength of semi-crystalline PEEK films was found to be enhanced by pretreatment of the films using RF plasma in Ar, N2 and O2 gases. The maximum bond strength was achieved when PEEK was treated with Ar plasma for 4 min and was still increasing with treatment time. Bond strength correlated positively with total oxygen concentration, positively with C-O group concentration and negatively with C=O group concentration. The positive correlation of strength with the polar component of surface energy is consistent with the correlation with total oxygen.