ESCA characterization of fluoropolymer film residue on carbon-fiber-reinforced plastic components

High-performance aerospace composite manufacturing of carbon-fiber-reinforc ed plastic (CFRP) components makes use of release films during standard cur e processes. After removal of a release film, unwanted residue from the fil m has been known to decrease the bond strength of adhesive joints in CFRP p arts. Electron spectroscopy for chemical analysis (ESCA) has been used as a relatively non-destructive surface analysis technique to determine the ato mic composition and chemical species present on the CFRP surfaces. The iden tification of the chemical species present on the surface can lead to a bet ter understanding of the overall bond structure and functional composition of the elements in a given surface, distinct from the bulk chemistry of the substrate. In this study, ESCA analyses were done on CFRP surfaces prepare d with two different fluoropolymer release films: fluorinated ethylene-prop ylene (FEP) and ethylene-tetrafluoroethylene (ETFE). Differences in the hig h-resolution spectra were used to determine the amount of fluoropolymer tra nsferred to the CFRP surface after removal of the release films. The ESCA q uantification showed that FEP release films transferred less material than ETFE release films to the surface of the cured CFRPs. Copyright (C) 2000 Jo hn Wiley & Sons, Ltd.