The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 20, 2021
Filed:
Sep. 29, 2015
Solvay Specialty Polymers Italy S.p.a., Bollate, IT;
Stefana Musio, Alessandria, IT;
Marco Malvasi, Novi Ligure, IT;
Valeriy Kapelyushko, Alessandria, IT;
SOLVAY SPECIALTY POLYMERS ITALY S.P.A., Bollate, IT;
Abstract
The invention pertains to a method for making a fluoropolymer dispersion, said method comprising an aqueous emulsion polymerization of one or more fluorinated monomers wherein said aqueous emulsion polymerization is carried out in an aqueous medium comprising a surfactant mixture [mixture (S)] comprising: at least one perfluorohexanoic acid or salt thereof [surfactant (C6)], in an amount of 1 to 5 g/I, with respect to said aqueous medium; and at least one linear bifunctional perfluoropolyether surfactant [surfactant (PFPE)] complying with formula (I) here below: XpOOC—CF-0-(CF0)(CFCF0)-CF—COOXp (I) wherein: Xp, equal to or different from each other, is a hydrogen atom, a monovalent metal, preferably an alkaline metal, or an ammonium group of formula —N(R'), wherein R′, equal or different at each occurrence, is a hydrogen atom or a C-Chydrocarbon group, preferably an alkyl group; n′ and m′ are independently integers >0 such that the number average molecular weight of the surfactant (PFPE) is of 500 to 2500, said surfactant (PFPE) being used in an amount of 0.005 to 0.5 g/I, with respect to said aqueous medium.