FLUOROPOLYMER DISPERSION PURIFICATION

摘要

The invention pertain to a process for purifying a fluoropolymer dispersion, said process comprising:
(i) providing an aqueous dispersion (D) of at least one fluoropolymer [polymer (F)] comprising at least one fluorinated surfactant [surfactant (FS)], having a solids content (SC) of 15 % by weight or more;
(ii) adding to said aqueous dispersion (D) at least one non-ionic non-fluorinated surfactant [surfactant (NS)];
(iii) adjusting said solid content (SC) to less than10 % by weight, to obtain a diluted aqueous dispersion (dD);
(iv) contacting said diluted aqueous dispersion (dD) with at least one adsorbing material, so as to obtain an aqueous dispersion of polymer (F) having a content of the fluorinated surfactant (FS) of less than 1 ppm based on the total weight of solids.
Still an object of the invention is an aqueous fluoropolymer dispersion comprising less than 1 ppm of fluorinated surfactant.