PLASMA PRETREATMENT OF POLYPROPYLENE FOR IMPROVED ADHESIVE BONDING

In this paper the effects of low-pressure plasma treatment of thermopl astic polypropylene (PP) substrates are shown. These substrates are co mpared to PP substrates which either remained untreated or were chemic ally pretreated. Owing to their low polarity the bonding properties of PP substrates are normally poor. The low-pressure plasma treatment wa s performed with different gases by a plasma generator at frequencies of 13.56 MHz and of 2.45 GHz. The specimen were bonded using Singel-Cy anoarylate adhesives, after which they were characterized both microst ructurally and mechanically. It was found that the plasma pretreatment improved the strength of the bonding, but the strength of the chemica lly pretreated specimens has not yet been reached. (C) 1998 Elsevier S cience S.A.