A NOVEL KRF LASER-INDUCED GRAFT REACTION OF POLY(ACRYLIC ACID) ONTO TETRAFLUOROETHYLENE-PERFLUOROALKYL VINYL ETHER COPOLYMER FILM

The surface of tetrafluoroethylene-perfluoroalkyl vinyl ether copolyme r (PFA) film in contact with poly(acrylic acid) (PAA) aqueous solution became wettable by excimer laser irradiation. The water contact angle of the PFA decreased from 106 degrees to 40-60 degrees by irradiation of KrF laser pulses (22.4-67.6 mJ cm(-2) pulse(-1)) with total irradi ation energy of 100-200 J cm(-2). The increase in amount of rhodamine 6G, a basic dye, adsorbed on the irradiated PFA surface showed a good correlation with reduction of the contact angle. Surface analysis by X -ray photoelectron spectroscopy indicated extensive loss of fluorine a toms and increase of oxygen atoms, in addition to a C1s spectrum simil ar to that of PAA. The present results demonstrate the introduction of a carboxylic group onto the PFA surface through a novel laser-induced graft reaction of PAA. Copyright (C) 1996 Elsevier Science Ltd.