Method of manufacturing reverse osmosis membrane, and reverse osmosis membrane manufactured thereby
There are provided a method of manufacturing a reverse osmosis membrane and a reverse osmosis membrane manufactured thereby. The method includes forming a polysulfone layer by applying a solution including a mixed solvent containing two or more solvents having different solubility parameter values to a surface of a porous support; and forming an active layer on the polysulfone layer.
1. A method of manufacturing a reverse osmosis membrane, the method comprising:
forming a polysulfone layer with a plurality of pores by applying a solution including a polymer having a sulfonic acid group and a mixed solvent containing first and second solvents having different solubility parameter values to a surface of a porous support; and
forming a polyamide active layer on the polysulfone layer,
wherein the first solvent is N,N-dimethylformamide (DMF), and the second solvent is γ-butyrolactone (GBL), the first solvent and the second solvent being mixed in a ratio of 80:20 to 60:40, and
wherein a percentage of the plurality of pores having a diameter of 40 nm or greater in the surface of the polysulfone layer is from 0.20 to 0.28%.
2. The method of claim 1 , wherein the solution comprises:
the polymer having a sulfonic acid group in an amount of 5 to 45 parts by weight, based on 100 parts by weight of the solution; and
the first and second solvents in an amount of 55 to 95 parts by weight, based on 100 parts by weight of the solution.