Untersuchung der Bildung von Polyesteramiden aus Dicarbonsäure-anhydriden und Oxazolidinonen-2

The well-known reaction of dicarboxylic acid anhydrides with epoxides, catalyzed by bases and yielding linear polyesters, has been extended by a variation of the reactants. The reactions of succinic and phthalic anhydrides with N-substituted oxazolidinones-2, which by their tendency to split off CO₂ may be regarded as ethyleneimine derivatives, give in the presence of a few mole percent of LiCl at 200–220°C. within 5–10 hr. polyester amides of molecular weights up to 3.500 in nearly quantitative yield. The polymer yield corresponds to the CO₂ evolution indicating an equal consumption of oxazolidinone and anhydride in the reaction. The experimental activation energies of 22.8 and 20.2 kcal./mole for the reaction of 3-phenyl oxazolidinone-2 with succinic and phthalic anhydrides, respectively, fairly agree with earlier values reported for the corresponding reactions of the cyclic carbonates.