Poly(tetrafluoroethylene)/polyamide thin-film composite membranes via interfacial polymerization for pervaporation dehydration on an isopropanol aqueous solution

Poly(tetrafluoroethylene)/polyamide (PTFE/PA) thin-film composite membranes were prepared via interfacial polymerization using surface-modified PTFE films as substrates. The composite membranes from the amine-functionalized PTFE films exhibit good layer compatibility and membrane stability due to the formation of covalent linkages between the PTFE substrate and PA layer. The composite membranes are applied to pervaporation dehydration processes on a 70 wt% isopropanol aqueous solution. The membranes are stable under the pervaporation dehydration operations and show a high-permeation flux of 1720 g/h m2 and a separation factor of 177. These PTFE-based thin-film composite membranes are potentially useful in pervaporation separation for other organic mixtures.