IMPROVEMENT IN POLYMER ADHESIVITY BY LOW AND NORMAL-PRESSURE PLASMA SURFACE MODIFICATION

The adhesivity of polyolefines and polyesters may be improved by exposure to preferably oxidizing plasmas of low pressure glow discharges. The results of polymer surface modification employing three different types of plasma jet (arc, spare and corona) are compared with those of d.c. and r.f. glow discharge modification. The adhesion of polypropylene and poly(ethyleneterephthalate) treated with atmospheric pressure plasma to polyurethane on aluminium achieves the technical requirements. However, low pressure plasma modification results in maximum adhesion. To compare the chemical processes occurring during low and atmospheric pressure plasma exposure on the polypropylene surface some efforts have been made to identify the plasma-introduced groups by employing functional group labelling by derivatization and X-ray photoelectron spectroscopy analysis.