COMPOSITION INCLUDING POLYETHYLENE GLYCOL FOR PREPARING MICROPOROUS POLYETHERSULFONE MEMBRANE AND METHOD FOR PREPARING MICROPOROUS MEMBRANE USING THE SAME

摘要

PURPOSE: Provided are a method for preparing a microporous polymeric separation membrane in which the membrane pore size can be easily controlled, and a polymer solution composition used in the preparation of the membrane. CONSTITUTION: The composition for preparing a microporous polyether sulfone membrane comprises N,N-dimethyl formamide as a solvent, and 15-25 parts by weight of a polyether sulfone as a base polymer and 0.5-40 parts by weight of a polyethylene glycol as an additive, based on 100 parts by weight of the solvent. The polyether sulfone membrane is prepared by the method comprising the steps of: (a) forming a polymer solution comprising the composition; (b) casting the polymer solution onto a support; (c) exposing the support on which the polymer solution is cast to the air having a constant humidity of 30% or more at a predetermined temperature for about 5 seconds to 3 minutes, and dipping into a non-solvent; and (d) washing and drying the membrane to remove the remaining solvent and additive, wherein the polyethylene glycol content, the exposure time or the air humidity in the step (c) is controlled to form the pores having a desired size on the membrane surface.