THE PLASTICIZATION OF A POLYURETHANE BY CARBON-DIOXIDE AT HIGH PNEUMATIC STRESSES

This paper describes a study of the interaction of high pressure subcritical and supercritical carbon dioxide with a polyurethane elastomer. A novel optical high pressure cell was employed to examine the gas-polymer interactions at a molecular level, using Fourier transform infra-red spectroscopy, at 42 degrees C and at a range of ambient pressures. Infra-red spectroscopic measurements, at atmospheric pressure, of the effect of temperature on the same polymer and a measure of the effect of temperature on the modulus on the polymer, again at atmospheric pressure, are used to estimate the effect of the absorbed gas on the modulus of the polymer.