Effect of ethylene glycol monobutyl ether on membrane forming systems and polyethersulfone with cardo performance and structure

Polyethersulfone with Cardo (PES-C) was a developed engineering thermoplastic and membrane material with high glass transition temperature. The effects of ethylene glycol monobutyl ether (EGME) on polymer precipitation curves in the triangle phase diagram, casting solution viscosity and the rate of gelation were studied by the methods of titration, Brookfield viscometer and gelation kinetics experiment, PES-C ultrafiltration membranes were prepared by phase inversion method using DMAC as solvent and EGME as additive. The effects of EGME on performance and structure of membrane were investigated, the experimental results from this work showed that the addition of EGME reduced the solvency of solvent for polymer from phase diagram. The increase of EGME concentration led the increase of casting solution viscosity, got the gelation rate stow down, which increased sponge structure. The relation between square of gelation front motion (d_z) and time (t) was not linear. Solute rejection increased and pure water flux decreased with increasing concentration of EGME.