Modification of molecular organization of polymers by gas sorption: Thermodynamic aspects and industrial applications

Abstract : In polymer science, gas–polymer interactions play a central role for the development of new polymeric structures for specific applications. This is typically the case for polymer foaming and for self-assembling of nanoscale structures where the nature of the gas and the thermodynamic conditions are essential to control. An important applied field where gas sorption in polymers has to be documented through intensive investigations concerns the (non)-controlled solubilization of light gases in the polymers serving, for example, in the oil industry for the transport of petroleum fluids. An experimental set-up coupling a vibrating-wire (VW) detector and a pVT technique has been used to simultaneously evaluate the amount of gas entering a polymer under controlled temperature and pressure and the concomitant swelling of the polymer. Scanning transitiometry has been used to determine the interaction energy during gas sorption in different polymers; the technique was also used to determine the thermophysical properties of polymers submitted to gas sorption. The role of the pressurizing fluid has been documented in terms of the influence of pressure, temperature, and nature of the fluid.