Aqueous solutions of copolymers, process for their preparation and their use as shell forming materials for the production of microcapsules by complex coacervation

摘要

Aqueous copolymer solutions containing water and 5-30% by weight of a polymeric mixture of (A) a copolymer, the structural units of which are 65-90 mol%, based on polymer, of statistically distributed residues of the acrylamide and 10-35 mol%. % consist of residues of maleic acid or maleic anhydride, with an intrinsic viscosity [η] of 0.05 to 1 [d1 / g], and (B) a copolymer whose structure units consist of statistically distributed polymerized residues of acrylamide, acrylic acid and maleic acid , where the maleic acid residues are at least partially in salt form and which has an intrinsic viscosity [η] of 0.05 - 1.5 [dl / g], with 65 - 90 mol%, based on polymer, residues of acrylamide and residues of acrylic acid together , and 10-35 mol% of residues of maleic acid which are at least partially in salt form, the weight ratio of the copolymers (A) and (B) 1. 2 to 20: 1, process for their preparation and their use as shell images for the production of microcapsules by complex coacervation.