Process for working up diacetone acrylamide solutions for the preparation of pure diacetone acrylamide

摘要

Improved process for working up diacetone acrylamide solutions, obtained by reaction of acetone or diacetone alcohol with acrylonitrile and sulfuric acid and subsequent dilution and neutralization, in which a) the organic phase obtained subsequent to the neutralization, which comprises the crude diacetone acrylamide, is hydrolyzed by addition of an aqueous alkaline solution in order to remove acrylamide, then b) after phase separation has been carried out, the organic phase, which comprises the crude diacetone acrylamide, is neutralized by addition of an acid, and c) in succession, low-boiling-point byproducts are removed by distillation in the presence of one or more polymerization inhibitors, then t-butylacrylamide is removed by distillation and, finally, the diacetone acrylamide is isolated by product distillation, and d) the diacetone acrylamide thus obtained is converted into its final form.