METHOD FOR ETCHING OF FLUOROPOLYMER TRACK MEMBRANES Russian patent published in 2021 - IPC B01D67/00 

FIELD: membrane technology.

SUBSTANCE: invention relates to the field of membrane technology, namely to methods for etching irradiated polymer films to obtain porous semi-permeable membranes. A method for etching a fluoropolymer track membrane is proposed, including chemical etching of a fluoropolymer film made of polyvinylidene fluoride irradiated with heavy charged particles in an aqueous alkali solution in the presence of potassium permanganate, while the fluoropolymer film is etched in a solution containing from 3.0 mol/l to 5.0 mol/l of alkali and from 0.2% to 1.0% of the mass fraction of potassium permanganate, etching is carried out in autoclave at a pressure of 0.2 MPa to 0.8 MPa and a temperature of 130°C to 180°C, while etching is carried out for no more than 80 minutes.

EFFECT: increase in the etching rate of tracks of fluoropolymer membranes made of polyvinylidene fluoride several times compared to analogues, a significant decrease in the concentration of aggressive reagents in the etching solution and a decrease in their consumption.

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