Preparation of anhydropolyamino acids
AssigneeMonsanto Company
InventorsGregory C. Alexander, Mark E. Jason, Dennis J. Kalota
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Abstract
There is disclosed a process for preparing polyaspartic acid by thermal condensation of L-aspartic acid in a novel catalyst which shortens the reaction time and increases the molecular weight of the polymer. The novel catalyst is a catalytically effective methylenephosphonic acid. Typical catalysts are 1-hydroxyethylidene-1,1-diphosphonic acid and aminotris(methylenephosphonic acid). The methylenephosphonic acid is blended with the amino acid in a molar ratio of amino acid to catalyst in the range of from about 1:1 to 40:1.
Claims13
A process for preparing anhydropolyamino acid which comprises heating L-aspartic acid to a temperature above about 140.degree. C. for a period of time sufficient to cause thermal condensation in the presence of a catalytically effective amount of a methylene phosphonic acid whereby the rate of said condensation is increased.
Dependencies are inferred from the claim text.