Method for the preparation of a particulate reversibly crosslinked polymeric material

摘要

The present invention relates to method for the preparation of a particulate reversibly-crosslinked polymeric material comprising: treating a particulate water-soluble hydroxyl-functional polymer in a liquid phase comprising a solvent mixture in that the hydroxyl-functional polymer is insoluble containing an organic solvent and water; a tetracarboxylic acid dianhydride represented by formula (I), 10 (I) wherein: U and V are independently selected from CH, N and P; 15 X is selected from a single bond, a saturated divalent (C1-C10) hydrocarbon group, O, S, NR, and PR, wherein R is selected from hydrogen and (C1-C4) alkyl; n and m are independently selected from 0 and 1; w is 1 or 2 with the proviso that; 20 if w is 1 then Y is X and if w is 2 then Y is selected from H and (C1-C4) alkyl, whereby there is no bond between both Y; and optionally a catalyst; to form a particulate reversibly-crosslinked polymeric material and 25 to a particulate reversibly-crosslinked polymeric material obtainable thereby.;

主权项

1. A method for the preparation of a particulate reversibly-crosslinked polymeric material comprising:treating a particulate water-soluble hydroxyl-functional polymer selected from hydroxyethyl celluloses and hydroxypropyl celluloses in a liquid phase comprising
a solvent mixture in that the hydroxyl-functional polymer is insoluble comprising an organic solvent and water, the amount of water being 2 to 50 weight %, based on the total weight of the solvent mixture; and a tetracarboxylic acid dianhydride; selected from group consisting of 1,2,3,4-butanetetracarboxylic acid dianhydride; ethylenediaminetetraacetic acid dianhydride; and 1,2,3,4-cyclopentanetetracarboxylic acid dianhydride;to form a particulate reversibly-crosslinked polymeric material.