The solubility and diffusion coefficient of carbon dioxide in the biodegrad
able polymers poly(butylene succinate) and poly(butylene succinate-co-adipa
te) were measured at temperatures from 323.15 to 453.15 K and pressures up
to 20 MPa. The solubilities iii the polymer's molten state increased linear
ly with pressure and decreased with temperature. Solubilities could be corr
elated to within 2.2% by the Sanchez-Lacombe equation of state in conjuncti
on with a temperature-dependent interaction parameter. The Sanchez-Lacombe
equation of state was also found to be applicable to the correlation of sol
ubilities in the semicrystalline state. The interaction parameter determine
d from fitting the solubility was inversely proportional to temperature. Th
e diffusion coefficients of carbon dioxide showed a weak concentration depe
ndence and had an order of magnitude of 10(-9) m(2)/s in the molten state.
The diffusion coefficients were correlated with the free-volume model of Ku
lkarni and Stern.