EFFECT OF MOLECULAR-WEIGHT PARAMETERS ON GAS-TRANSPORT PROPERTIES OF POLY(2,6-DIMETHYL-1,4-PHENYLENE OXIDE)

The gas permeability of O-2 and N-2 for homogeneous and composite memb ranes prepared from poly(2,6-dimethyl-1,4-phenylene oxide) (PPO) sampl es with different molecular weight parameters was investigated. Temper ature dependencies of gas permeability coefficients and permselectivit y were determined for homogeneous membranes. It was established that g as permeability coefficients of homogeneous membranes depend on molecu lar weight of the polymers used. The gas permeability of composite mem branes with a PPO selective layer was investigated as a function of PP O intrinsic viscosity [eta] and its casting solution concentration (c) . It was shown that under the condition [eta]. c = const it is possibl e to obtain composite membranes with the same transport properties by using polymers with different molecular weight parameters. (C) 1996 Jo hn Wiley & Sons, Inc.