Solubility and diffusivity of CO2 in carboxylated polyesters

The solubility of CO2 in saturated polyester resins at different temperatures (306 and 343 K) and pressures (0.1–30 MPa) has been measured using a magnetic suspension balance. The solubility data were used for estimating the binary diffusion coefficients. The results show a good solubility of CO2 in polymers, up to 0.64 g CO2/g polymer. The diffusion coefficients of supercritical CO2 in polymers have generally high values and are in the range from 0.156 × 10−8 to 10.38 × 10−8 cm2/s. DSC and XRD analyses of the semi-crystalline polymer samples indicate that amorphous degree of polymers after exposure to CO2 is increased. The observed structural effects are dependent on pressure, temperature and time of exposure to CO2.