Back to results
US 4,839,461 AGranted
Polyaspartic acid from maleic acid and ammonia
AssigneeBayer Aktiengesellschaft
InventorGunther Boehmke
Life of this patent
Estimating the term…
Abstract
Polyaspartic acid and its salts, which can be obtained by reacting maleic acid and ammonia in a molar ratio of 1:1-1.5 at 120.degree.-150.degree. C. and , if appropriate, converting the acid into salts, are used for removing and preventing incrustations formed by the hardness constituents of water, or as a fertilizer.
Claims2
A process for the preparation of a salt of polyaspartic acid comprising reacting maleic acid and ammonia in a molar ratio of 1:1-1.5 at 120.degree.-140.degree. C., and converting the resultant acid into a salt by adding a metal hydroxide or ammonium hydroxide to the acid.
Dependencies are inferred from the claim text.