A premier in polymer chemistry: the cycloaddition of bisoxaziridines with 4,4'-methylene diphenyl diisocyanate yields novel linear poly(1,2,4-oxadiazolidin-5-one) derivatives. The polymers are relatively stable (>200 °C) and model reactions show that the reaction rate strongly depends on the electronic properties of the oxaziridine unit; electron-donating substituents on the C atom of the heterocyclic ring promote the cycloaddition.
