Abstract: A method for hydrolysis of polyurethane foam and recovery of diamines and polyethers (or polyesters) from the hydrolysate carried out near atmospheric pressure and temperatures above about 185.degree. C. in a reaction zone containing water vapor which comprises increasing the rate of diamine production by inclusion of a minor, but effective amount of ammonia in the reaction zone. Volitilized diamines separated from the foam are preferably removed from the reaction zone, e.g. in an overhead stream, while polyethers (or polyesters) separated from the foam are recovered as liquid bottoms from the reaction zone.

Abstract: Effective antioxidant levels in hydrocarbonaceous materials are determined by (a) establishing the rate of uninhibited oxygen absorption for a standard liquid comprising (i) an oxidizable material susceptible to free radical oxidation and (ii) an agent that causes free radical oxidation; (b) establishing the rate of oxygen absorption for a test liquid comprising (a) (i) and (a) (ii) and a dispersible amount of the hydrocarbonaceous material or extract therefrom comprising antioxidant; (c) ascertaining the delay before uninhibited oxygen absorption of the test liquid and (d) determining the effective concentration of the antioxidant in the hydrocarbonaceous material. If the antioxidant in the hydrocarbonaceous material is known, the concentration can be accurately determined.

Abstract: A method for recovering methyl methacrylate from a mixture of polymeric materials containing poly (methyl methacrylate) which comprises contacting the mixture with a boiling C.sub.5 - C.sub.8 alkane, separating an insoluble residue containing poly (methyl methacrylate) from the alkane and its extract, extracting poly (methyl methacrylate) from such insoluble residue with boiling acetone, separating the poly (methyl methacrylate) from the acetone, and recovering the methyl methacrylate monomer from such poly (methyl methacrylate) by pyrolysis. In a preferred embodiment, the poly (methyl methacrylate) containing solid obtained after the acetone extraction is compressed under elevated temperatures and pressures prior to pyrolysis. The method can be stopped prior to the pyrolysis step when it is desired to recover only the poly (methyl methacrylate).