| 摘要 |
<p>Dicarboxylic acids or dicarboxylic acid esters, containing a N,N-heterocyclic radical, of the formula in which the two R1 independently of one another each denote hydrogen, an alkyl with 1 to 4 C atoms or a phenyl, the two R2 independently of one another each denote hydrogen or an alkyl with 1 to 10 C atoms, the two n represent identical or different numbers from 2 to 12 and X denotes a divalent monocyclic N,N-heterocyclic radical of benzimidazolone, parabanic acid, 2,2-dimethylimidazolidine-4,5-dione, 6-ethyl-uracil or barbituric acid are prepared by reacting 1 mol of the corresponding N,N-heterocyclic compounds with 2 mols of a compound of the formula wherein Y1 denotes a chlorine or bromine atom. The dicarboxylic acid compounds have a high stability to heat and therefore are very suited for the manufacture of polycondensates by the melt condensation process.</p> |
