Process for preparation of polyvinyl alcohol-polyether graft copolymers via extrusion
AssigneeBASF SE
InventorsNorbert Guntherberg, Tanja Seebeck, Ronald Lange
Life of this patent
Estimating the term…
Abstract
The present invention relates to a process for preparation of graft copolymers which have repeat units derived from vinyl alcohol and have polyether groups, via reactive extrusion of corresponding graft copolymers based on esters of vinyl alcohol in the presence of water and/or of at least one C1-C6 alkanol, and of a base.
Claims24
A process for preparing of graft copolymers P2 that have repeat units derived from vinyl alcohol and have polyether groups, the process comprising contacting graft copolymers precursors that have repeat units derived from esters of vinyl alcohol and have polyether groups with water or with at least one C1-C6 alkanol or a mixture of the water and the alkanol in the presence of a catalyst, where the reaction with the precursors and the water, the alkanol or mixture thereof occurs in an extruder.
A process comprising:
- inputting a mixture comprising graft copolymer precursors, and water, C1-C6 alkanol or a mixture thereof to a first feed zone of an extruder;
- inputting a base to the first feed zone or a second feed zone downstream from the first feed zone of the extruder;
- wherein the reaction between the graft copolymer precursors and the water, the C1-C6 alkanol or the mixture thereof occurs primarily in a reaction zone of the extruder;
- and
- removing the graft copolymer product from the output zone of the extruder.
Dependencies are inferred from the claim text.