| Abstract: | Nuclear magnetic resonance (NMR) is used to characterize properties of polyetherimide membranes obtained from a phase inversion process. At the end of the phase inversion and prior to the subsequent thermal treatments, the membrane is made of a porous structure filled of solvent and nonsolvent molecules embedded in a concentrated polymer–solvent matrix in the glassy state. The confinement of the small solvent and non solvent molecules in the porous system leads to a restriction of their mobility. The kinetics of membrane formation is observed from NMR. It is found that the penetration of non-solvent and the propagation of the glassy phase into the system obey simple diffusion laws. © 1993 John Wiley & Sons, Inc. |
