Preparation of highly reflective films by supercritical infusion of a silver additive into poly(ether ether ketone)

Abstract

There has been a great interest in preparing polymeric reflective surfaces in the last few years. The application of supercritical fluid technology in this area is beginning to receive a great deal of attention. Poly ether ether ketone (PEEK) is well known for its excellent thermal, chemical, mechanical and electrical properties. These properties make it ideal for use in aerospace, electrical, fluid handling and coating industries. Supercritical infusion of a silver-containing additive (1,5-cyclooctadiene- 1,1,1,5,5,5-hexafluoroacetylacetonato)silver(I) into a PEEK film was achieved with moderately high density CO2 at various temperatures, pressures, and times.

During the infusion process: 1) polymer sample was exposed to both supercritical CO2 and the additive under pressure for a brief time, 2) depressurization of the system caused the CO2 to rapidly diffuse out of the polymer; while the remaining additive in the polymer desorbed at a much slower rate governed by its diffusivity in the CO2-free polymer. Following this process the infused film was heated for a short time period to thermally reduce the infused metal and to form a reflective surface. In this research the effect of different additive concentrations, infusion conditions (e.g. temperature, pressure, time), and curing conditions (e.g. air flow rate, temperature, time) on the nature of the PEEK surface will be presented.