Self-supporting pH- and temperature-responsive ethyl cellulose-g-PDMAEMA microporous membranes through non–solvent-induced phase separation process

First, ethyl cellulose-g-poly(2-(dimethylamino) ethyl methacrylate) (EC-g-PDMAEMA) was synthesized through atom transfer radical polymerization. Second, the polymer was used to prepare self-supporting microporous membranes through nonsolvent-induced phase separation process. The chemical structures of EC0.2-g-PDMAEMA15 was confirmed by 1H NMR and FTIR. And the copolymer micelles were characterized by UV, laser particle-size analysis, and TEM. The results indicated that the copolymer had pH- and temperature-responsive behaviors. Furthermore, the morphology study of microporous membranes indicated that the pores became smaller and more uniform with the increase of tetrahydrofuran (THF) content and “open time”, and the most optimal preparation conditions were using 75% THF/25% DMF (v/v) as solvents with the “open time” 30 s. What’s more, the membranes were responsive to pH and temperature stimulus in terms of water flux.