Concentrated aqueous dispersions of tetrafluoroethylene polymers, and process for their preparation

US5219910A · kind A · utility

Assignee

• Hoechst GmbH · DE

Inventors

• Karlheinz Stahl · Hofheim, DE
• Wolfgang Neumann · Gernrode, DE
• Hubert Seitz · Altötting, DE

Key dates

• Filing date: Jul 17, 1992
• Grant date: Jun 15, 1993
• Expiry date: Jul 17, 2012

Classification

• Technology area (CPC D): Textiles; Paper
• CPC primary: D06N3/047
• WIPO field: Textile and paper machines
• WIPO sector: Mechanical engineering

Abstract

Concentrated, aqueous, colloidal dispersions of tetrafluoroethylene polymers having a polymer solids content of 25 to 70% by weight, which comprise, as the dispersion stabilizer, an amine oxide of the formula ##STR1## in which R.sup.1 is an alkyl radical having 6 to 22 carbon atoms or a mixture of such alkyl radicals and R.sup.2 is an alkyl radical having 1 to 22 carbon atoms or a mixture of such alkyl radicals, and in which R.sup.1 and R.sup.2 are identical or different and 50 to 0% by weight of the alkyl radicals R.sup.1 and R.sup.2 can be replaced by alkenyl radicals having 6 to 22 carbon atoms and having 1 to 3 C.dbd.C double bonds, are obtained by concentration with addition of these dispersion stabilizers. The dispersions are used for impregnating yarns and textile sheet-like structures.