Reactions of N,N^′-bis(2-hydroxyethyl)oxalamide with Ethylene Carbonate and Use of the Obtained Products as Components of Polyurethanes Foams

Figure 3

¹H-NMR spectra of the reaction product of BHEOA : EC : (a) 1 : 4 at 140^∘C, (b) 1 : 6 in the presence of 0.06 mole K₂CO₃/mole OA at 160^∘C.

(a)

(b)