Process for the manufacture of swellable, absorptive polymers of polyhydroxy methylene
AssigneeHoechst Aktiengesellschaft
InventorsArno Holst, Michael Kostrzewa
Life of this patent
Estimating the term…
Abstract
This invention relates to a process for the manufacture of absorptive polymers which are at least preponderantly insoluble in water, but capable of swelling in water, which comprises etherifying polyhydroxy methylene in a homogeneous phase in an aqueous alkaline solution with an .alpha.-halogen carboxylic acid, and prior to, during, or after the etherification process performing a further reaction with a cross-linking agent which is polyfunctional towards polyhydroxy methylene in an alkaline medium.
Claims5
A process for the manufacture of absorptive polymers which are at least more than 50 per cent by weight insoluble in water, but capable of swelling in water, which comprises etherifying polyhydroxy methylene in a homogeneous phase in an aqueous alkaline solution with an .alpha.-halogen carboxylic acid, and prior to, during, or after the etherification process performing a further reaction with a cross-linking agent which is polyfunctional towards polyhydroxy methylene in an alkaline medium selected from the group consisting of epoxy compounds, halohydrins, polychlorinated higher alcohols, divinyl sulfone, acid chlorides, dichloroacetic acid and compounds in which the groups which are functional towards polyhydroxy methylene are the acryl amido group, the chloro azomethine group, or the allyloxy azomethine group.
Dependencies are inferred from the claim text.