MULTILAYER COMPOSITE POLYMER STRONGLY BASIC MEMBRANE AND METHOD FOR PRODUCTION THEREOF Russian patent published in 2015 - IPC B01D71/06 B01D71/82 B01D71/60 B01D61/44 C08J5/22 

FIELD: chemistry.

SUBSTANCE: invention relates to membrane engineering. A multilayer composite polymer strongly basic membrane, which includes at least two polymer layers, a first layer which forms a substrate of the composite membrane, contains quaternary ammonium bases with three alkyl substitutes at the nitrogen atom and a surface layer containing a polymer ion with quaternary amines, bidentately bonded to a matrix by two C-N bonds. A method of producing a composite polymer membrane includes treating a membrane made of a polymer containing strongly basic quaternary ammonium bases with three alkyl substitutes at the nitrogen atom with an alkali solution to form, in the initial membrane, a thin hydrolysed layer containing secondary and tertiary amino groups, washing the membrane from the alkali solution with water to a neutral pH, treating with an acid solution until complete protonation of the secondary and tertiary amino groups, followed by treating the membrane with a copolymer of acrylonitrile with dimethyldiallylammonium chloride until formation, in the surface layer, of immobilised quaternary amino groups which are bidentately bonded with the matrix of the membrane by two C-N bonds.

EFFECT: providing stable operation of a composite membrane in electrodialysis apparatus at a current value which is considerably higher than the maximum current and at high pH values of the treated solution.

2 cl, 5 tbl, 4 dwg