To provide an economical and effective method substituting for conventional methods for the direct synthesis of isocyanate and polyisocyanate.
This invention relates to a one-pot method for synthesis of isocyanates, polyisocyanates or mixtures thereof. The method includes the steps of (i) preparing a mixture comprising an amine, an alcohol, an oxygen-containing gas, carbon monoxide, a metal complex catalyst selected from the group consisting of macrocyclic complex catalysts and cobalt Schiff base catalysts; and a solvent selected from the group consisting of aliphatic or aromatic halocarbons, perhalogenated alcohols, halogenated ethers, halogenated ketones, perfluorinated hydrocarbons, polymers of chlorotrifluoroethylene having the formula -(CF2-CFCl)n (wherein n is between 2 and 10) and mixtures thereof, (ii) subjecting the resulting mixture to a first heating under pressure, (iii) cooling and depressurizing the mixture resulting from the previous step and (iv) subjecting the mixture to a second heating to separate out the isocyanate product from the mixture.
ALMENA MUNOZ BEATRIZ
PADILLA POLO ANA
OREJON ALVAREZ ARANCHA
CLAVER CABRERO CARMEN
CASTILLON MIRANDA SERGIO
SALAGRE CARNERO PILAR
Koichi Niimi