Surface photodegradation and modification of some substituted polyacetylene films

Abstract

Surface photodegradation and surface modification by graft copolymerization have been carried out on films of two substituted polyacetylenes, viz. poly((o-(trimethylsilyl)phenyl)acetylene) or poly(o-Me3SiPA) and poly(1-chloro-2-phenylacetylene) or PCPA. X-ray photoelectron spectroscopy (XPS) data indicate that surface degradation induced by near-UV light in the former involves oxidation of the Si hetero-atoms to the Si-O species, whereas the latter polymer photodegrades via the loss of the Cl hetero-atoms. The surface photodegradation processes in both polymers are facilitated by the presence of O2 and H2O. Both polymer films undergo near-UV induced graft copolymerization with acrylamide (AAm), acrylic acid (AAc), Na salt of styrene sulfonic acid (NaSS) and 3-dimethyl(methacryloyloxyethyl) ammonium propane sulfonate (DMAPS) to give more hydrophilic surfaces. The graft density in each case is substantially enhanced for polymer films pre-treated with Ar plasma. Near-UV light induced graft copolymerization in all cases also results in the surface photodegradation of the two acetylene polymer films. © 1993.