CHEMICAL-VAPOR-DEPOSITION OF SILVER ON PLASMA-MODIFIED POLYURETHANE SURFACES

The surface chemistry of 4,6-octanedionato)(trimethylphosphine)-silver (I)], [(fod)AgP(CH3)(3)], a silver precursor for chemical vapor deposi tion (CVD), has been investigated on plasma-modified polyurethane surf aces by means of reflection-absorption infrared spectroscopy (RAIRS) a nd X-ray photoelectron spectroscopy (XPS). On the unmodified polyureth ane surface, the RAIRS and XPS data show that [(fod)Ag(P(CH3)(3))] rea cts with polyurethane C=O, N-H, and C-O-C groups present at the surfac e by displacing the Lewis base P(CH3)(3); these acid-base reactions yi eld the formation of surface Ag-O and Ag-N bonds. Air plasma treament of the polyurethane surface leads to the incorporation of C=O and C-O- O functional groups, as well as the conversion of C-N(H)- into C=N- fu nctional groups by the abstraction of hydrogen. RAIRS data obtained fo llowing O-2 and air plasma treatment showed that, in addition to graft ing of functional groups, polyurethane chains change their conformatio n in the polyurethane film. The increase of silver concentration resul ting from CVD is proportional to the increase of oxygen incorporated o n the polymer surface. This study shows that CVD on soft polymers can be performed at room temperature.