Poly:succinimide, poly:aspartic acid and maleamic acid prepn. without extraneous additives

摘要

Continuous prepn. of polymers (I) with recurring succinyl units comprises: (i) mixing (A) maleic anhydride (II) or its deriv. with (B) NH3 (source) or amides of carbonic acid; (ii) conversion to a low mol. -contg. maleic acid derivs. (III) in a first exothermic reaction stage; and (iii) polymerisation of (III) in a second stage. The novel features are that: (a) stage (i) is carried out adiabatically and the heat of reaction is used to bring the reaction mixt. to the polymerisation temp. and (b) (III) is at least partly polymerised to (I) in stage (iii). Also claimed is a process for continuous prepn. of maleamic acid (IV) by mixing (II) (deriv.) with NH3 (source) rapidly in less than 2 seconds and reaction in a reactor in which the dwell and temp. ensure (almost) no polymerisation. (A) is (II), its derivs. maleic acid and/or fumaric acid; and (B) is NH3, NH4HCO3, (NH4)2CO3 or ammonia salts and amides or carbonic acid. e.g. urea, isourea (ammonium cyanate) carbamic acid and/or ammonium carbamide. Other monomers may be added continuously to (A, B) e.g. alcohols, opt. unsatd. di- and poly-carboxylic acids, unsatd. monocarboxylic acids etc..