Synthesis of polyenamines by vinylogous nucleophilic substitution polymerization of 2,2′‐disubstituted bis(4‐ethoxymethylene‐5‐oxazolone) with diamines

A new class of polyenamines was synthesized by the vinylogous nucleophilic substitution polymerization of 2,2′‐p‐phenylenebis(4‐ethoxymethylene‐5‐oxazolone) with diamines in polar aprotic solvents under very mild conditions. The polymers derived from aliphatic diamines were soluble in these solvents and had inherent viscosities in the range of 0.3–0.9. The dilute solutions showed marked decrease in viscosity with time, presumably due to hydrolytic chain scission of the enamine structures in the polymer backbone. The polymers exhibited no melting temperature, and onset of breakdown under thermogravimetric analysis in a nitrogen atmosphere occurred at 250–300°C.