Explosion taming surfactants for the production of perfluoropolymers

US8119750B2 · kind B2 · utility

Assignee

• 3M INNOVATIVE PROPERTIES COMPANY · US

Inventors

• Klaus Hintzer · Woodbury, US
• Michael Jürgens · Rheydt, DE
• Harald Kaspar · Altötting, DE
• Andreas Maurer · Zürich, CH
• Werner Schwertfeger · Altötting, DE
• Tilman C. Zipplies · Burghausen, DE

Key dates

• Filing date: Jul 13, 2006
• Grant date: Feb 21, 2012
• Expiry date: Mar 26, 2030

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C08F14/26
• WIPO field: Macromolecular chemistry, polymers
• WIPO sector: Chemistry

Abstract

A process comprising polymerizing tetrafluoroethylene in an aqueous emulsion in the presence of a non-telogenic surfactant having an anionic portion with the general formula (I):Rf—O-L-CO2—  (I)wherein Rf is selected from a partially fluorinated alkyl group, a perfluorinated alkyl group, a partially fluorinated alkyl group interrupted by one or more oxygen atoms, and a perfluorinated alkyl group interrupted by one or more oxygen atoms, wherein Rf has from 1 to 10 carbon atoms; and L is an alkylene group having the general formula (CX2)n wherein each X is independently selected from Rf, fluorine, and hydrogen and n is selected from 1 to 5, with the proviso that the surfactant contains at least one unit selected from a —CH2— unit and a —CHF— unit. Also provided are aqueous dispersions comprising these surfactants and methods of coating substrates with the aqueous dispersions.