Elaboration of porous poly(ether-imide) membrane using vapor induced phase separation

Abstract

Polymeric films were prepared from poly (ether-imide)/N-methyl-2-pyrrolidinone solutions using vapor induced phase separation process at 40 oC. The influence of such operating conditions as relative humidity and polymer concentration on the final morphology was investigated in order to consider potential future membrane applications with the objective of elaborating presupposed quality porous materials. In our experiments, the water vapor concentration in the atmosphere used during the film forming process was the predominant parameter governing the microstructure. Polymeric films with a cellular morphology were produced for a processing relative humidity (RH) higher than 30% whereas dense homogeneous films were obtained below this value. The influence of the polymer concentration was studied at 40 % RH. The results were discussed with respect to the cell and pore size and to the occurrence of macro-void defects.

Keywords

• vapor induced phase separation
• poly (ether-imide)
• porous membrane
• morphology