Concentration dependence of diffusivities of penetrants in glassy polymer membranes

摘要

AbstractSteady‐state permeation rates for pure CO2, CH4, and O2through two kinds of homogeneous dense membranes, copolymer of methyl methacrylate andn‐butyl acrylate and poly(methyl methacrylate), were measured at three temperatures between 20 and 40°C and upstream pressures up to 3 MPa. The logarithms of the mean permeability coefficients for CO2in both membranes increased linearly or quadratically with increasing upstream pressure, whereas the mean permeabilities for CH4and CO2were independent of pressure. The pressure dependence of the mean permeability coefficient for CO2was interpreted in terms of a modified free‐volume model of diffusion for a Henry's law population in glassy polymers. © 1993 John WileySo