Metallized poly(etherether ketone) films achieved by supercritical fluid impregnation of a silver precursor followed by thermal curing

Reflective PEEK films with silver surfaces were prepared by supercritical fluid impregnation with CO2 as the carrier and subsequent thermal reduction of (1, 5-cyclooctadiene-1,1,1,5,5,5-hexafluoroacetylacetonato) silver(I) dimer, [Ag-(COD)HFA](2). No chemical reducing agent was needed to effect silver reduction. Reflectivity of the surface was dependent on the impregnation and cure conditions. At constant CO, pressure and impregnation time, the reflectivity of the surface increased as the impregnation temperature increased. At constant temperature and CO2 pressure, the reflectivity increased as the impregnation time increased. Thermal cure parameters at fixed impregnation conditions suggested that lower cure temperatures required longer cure times in order to obtain high reflectivity. Silver particles <10 nm in diameter appeared in the film bulk near the surface. Different sized silver clusters on the surface could be grown by controlling the impregnation and cure conditions. The silver on the surface strongly adhered to the polymer surface. (C) 2002 Elsevier Science B.V. All rights reserved.