| Abstract: | Chemical recycling of a polyurethane elastomer and a flexible foam based on methylenebis(phenyl isocyanate) (MDI) and a polyetherpolyol was performed by ammonolytic cleavage of urethane and urea bonds under supercritical conditions. Resulting products were the polyols, the amines corresponding to the isocyanates used, and unsubstituted urea. Under suitable conditions the polyetherpolyol was completely separated from the other ammonolysis products which in turn can be further separated and used for the manufacture of polyurethanes or for the synthesis of diisocyanates. |
