Method for cleaving urethanes

A process for chemolyzing a urethane based on an isocyanate component and an alcohol component by reaction with a chemolysis alcohol to form a carbamate of an isocyanate of the isocyanate component and of the chemolysis alcohol, comprising the steps of:

• (A) providing the urethane and
• (B) chemolyzing the urethane from (A) with the chemolysis alcohol in the presence or absence of a chemolysis catalyst, where the chemolysis alcohol at 1013 mbar has a boiling point of not more than 200° C., and where a mass ratio of the chemolysis alcohol to the urethane, m(chemolysis alcohol)/m(urethane), is in the range from 0.50 to 15, to form a chemolysis product comprising the carbamate,
• wherein the chemolysis alcohol is selected from (i) an aliphatic secondary or tertiary monoalcohol, (ii) an aliphatic primary monoalcohol bonded to two or three further carbon atoms, at at least one carbon atom in the β position or γ position to the hydroxy group of the monoalcohol, (iii) an aromatic monoalcohol or (iv) a mixture of two or more of the aforementioned chemolysis alcohols.