Pervaporation separation of DMF from water using a crosslinked polyurethane urea-PMMA IPN membrane

Interpenetrating network (IPN) membrane of HTPB-based polyurethane urea (PUU) and poly (methyl methacrylate) (PMMA) was developed and used in the pervaporation separation of water-dimethyl formamide (DMF) mixtures of different compositions. From these data the permeation flux, separation selectivity, degree of swelling were calculated at 25, 40 and 60°C. At a higher temperature, the permeation of diffusing molecules through the membrane becomes easier, resulting in an increase of DMF flux. Again with the increase in PMMA content in the membrane the DMF flux and separation selectivity values are increased due to the presence of more polar groups of PMMA. The membrane showed more selectivity towards DMF than water. The highest DMF flux of 0.231 kg/m2.h was obtained for the PUU-PMMA-3 membrane at a temperature of 60°C for 80% DMF in the feed.