VERFAHREN ZUR HERSTELLUNG VON POLYASPARAGINAMIDSAEURE UND IHREN SALZEN.

摘要

Polyasparagine-amide acid and its salts are prepd. by reacting maleic acid and NH3 in molar ratio 1:1-1.5 at 120-150 deg.C and opt. converting the acid to the salts. (a) In the prepn. maleic acid and NH3 are heated in 4-6 hrs. to 125-135 deg.C and then kept 0-2 hrs. at this temp.. (b) salts of asparagine-amide are prepd. by: (i) heating maleic acid and NH3 in 4-6 hrs. to 125-135 deg.C and keeping at this temp. for 0-2 hrs.; (ii) cooling to 100-120 deg.C and (iii) adding aq. solns. or suspensions of metal or ammonium hydroxides, esp. of Na-, K-, Li-, Mg-, Ca-, ammonium, alkyl-ammonium, Zn- or Fe hydroxides.