Washing process for the purification of polymers containing N or amino, ammonium or spirobicyclic ammonium groups

US6806350B2 · kind B2 · utility

Assignee

• DSM Fine Chemicals Austria NFG GmbH & Co KG · AT

Inventors

• Michael Stanek · San Clemente, US
• Regina Schitter · Linz, AT
• Gerhard Steinbauer · Ansfelden, AT
• Gerald Summer · Linz, AT
• Peter Hildebrand · Pfronten, DE

Key dates

• Filing date: Feb 24, 2003
• Grant date: Oct 19, 2004
• Expiry date: Feb 24, 2023

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C08F6/008
• WIPO field: Macromolecular chemistry, polymers
• WIPO sector: Chemistry

Abstract

The invention relates to a washing process for cleaning polymers containing N or amine, ammonium or spirobicyclic ammonium groups, comprising cationic groups containing N, in addition to suitable counterions, whereby the gelled-out polymers are obtained through polymerization and cross-linking by a) adding a base which is partially or fully deprotonated, b) the partially or fully deprotonated polymers are washed, then c) optionally, are reprotonated in an organic solvent or in an organic solvent/water mixture by adding an acid, whereupon d) optionally, they are washed in an organic solvent or an organic solvent/water mixture in order to shrink the gels and optionally, e) in connection with step c) or d), the steps a)-c) or -d) are repeated.