Phase inversion in reusable baths (PIRBs): A new polymer membrane fabrication method as applied to EVOH

摘要

A flexible version of the phase inversion variety of porous membrane fabrication that employs cold solvent as a solidification bath is presented. A nonsolvent is included both in the dope and in the bath, and the liquid compositions are such that the bath is reusable; the concept is demonstrated for the water/dimethyl sulfoxide/poly(ethylene-co-vinyl alcohol) system. The effects of the reusable bath (RB) temperature and the bath strength on membrane morphologies are explored. From the pure water flux measurements, it is found that membranes prepared from RB possess higher permeation fluxes than those from other baths. Filtration against blue dextran (2000 kDa) indicates that those membranes precipitated from RB at 5 degrees C exhibit the highest rejection (98%) at the permeation flux of 14.56 L m(-2) h(-1). In addition, it is found that the composition of the RB remains unchanged after 240 applications of the new process. (c) 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 48193.