METHOD OF MANUFACTURE OF A GAS-SEPARATING COMPOSITE MEMBRANE Russian patent published in 2003 - IPC

FIELD: chemical, petrochemical, medical industries. SUBSTANCE: invention presents a method of manufacture the gas- separating composite membrane, that may find application in processes of gas-separation and concentration of the gases used in chemical, petrochemical, medical industries. The working solution of a block-copolymer is being prepared as the micellar system by a spontaneous dispersion of the block-polymer with its simultaneous mixing with dissolvent and nonsolvent, taken in the following ratio of mass shares: the block-polymer - 1, dissolvent - from 2 up to 40, nonsolvent - from 6 up to 35. The gas selecting layer shaping is exercised from this solution on the hydrophobic porous substrate made in the form of the ultra- or microfiltration membrane by a dry method using bonded fabric of the polypropylene or the polyester fibers, having the pores sizes chosen from the ratio: Ds = (0,05-0,9)Dm, where Ds is the pores size of the substrate, Dm is the size of micelles of the working solution of the block-copolymer - an equivalent diameter. The block- copolymer is chosen from the group - oligoarylate with oligodimethylsiloxane, oligocarbonate with α- oligobiscloreformatesiloxane, ω-bis(diethylamino)organosiloxane oligomer with phenylsylsesquioxane oligomer or oligosulphone with oligobutadiene. In the capacity of dissolvent they use methylene chloride or chloroform. In the capacity of non-solvent - hexane or petroleum ether. EFFECT: the invention ensures high efficiency and reliable operation alongside with high industrial reproducibility of the gas-separation properties in the systems of CO₂-O₂-N₂. gases. 2 cl, 3 tbl, 13 ex, 1 dwg