Organic solvent-soluble copolymer polyester, composition for forming ultrafiltration membrane comprising same, and high water permeability reverse osmosis membrane prepared therefrom

A reverse osmosis membrane, comprising:

• a porous support layer;
• and
• an ultrafiltration membrane formed on one surface of the porous support layer, wherein the ultrafiltration membrane comprises a copolymerized polyester that is dissolved in an organic solvent and that is formed by an esterification reaction between an acid component comprising at least one C8-12 aromatic dicarboxylic acid and a diol component consisting of ethylene glycol and neopentyl alcohol,
• wherein the molar ratio (NC/NO) of the number of carbon atoms (NC) and the number of oxygen atoms (NO) in the copolymerized polyester is 2.8 to 3.2, and the solubility of the copolymerized polyester in dimethylformamide (DMF) at room temperature is 20% by weight or more, and
• wherein the reverse osmosis membrane has a water permeability of 200 to 1,000 gfd as measured according to the measurement conditions below:
• the reverse osmosis membrane when operated at a temperature of 25° C. and a pressure of 1 kgf/cm2 using raw water, which is deionized water (DI), to measure the water permeability.