POROUS MEMBRANE FROM VINYLIDENE FLUORIDE RESIN AND METHOD OF ITS PRODUCTION Russian patent published in 2012 - IPC B01D71/44 B01D69/08 C08J9/26 C08J9/28 

FIELD: process engineering.

SUBSTANCE: invention relates to porous membrane intended for water treatment and to method of its production. Porous membrane made from vinylidene fluoride resin with limit of particles passage of at least 0.2 mcm comprises opposed first and second surfaces. Note here that first surface has micro pores of round or oval shape with mean relation between larger axis and smaller axis varying from 1:1 to 5:1, while second surface has slot-shaped micro pores with mean relation between larger axis and smaller axis making at least 5:1. Method of producing porous membrane comprises cooling of initial solution containing vinylidene fluoride resin, solvent, inorganic particles and agent provoking aggregation wherein inorganic particles and agent feature affinity while solvent and agent are immiscible or feature the maximum critical temperature of dissolution for inducing phase separation with subsequent hardening, and extraction of porous membrane before complete removal of solvent, inorganic particles and agent.

EFFECT: higher permeability, fractionation properties, physical and chemical strength.

11 cl, 6 dwg, 4 tbl, 6 ex