PREPARATION OF ANHYDROPOLYAMINO ACIDS

摘要

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.