Process for the preparation of methylene-bridged diaryl isocyanates
AssigneeOlin Corporation
InventorsJohn S. Babiec, Jr., Wilhelm J. Schnabel
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Abstract
A process for the production of methylene-bridged diaryl isocyanates by the reaction of .alpha.-halomethyl aromatic compounds with aromatic isocyanates in the presence of a catalyst. The catalyst comprises a metal salt of an aliphatic or cycloaliphatic organic acid where the metal is zinc, cadmium or mercury. Methylene-bridged diaryl isocyanates are suitably used in the production of polyurethane elastomers and foams.
Claims12
In a process for preparing methylene-bridged diaryl isocyanates by reacting an .alpha.-halomethyl aromatic compound with an aromatic isocyanate at a temperature in the range of from about 100.degree. to about 250.degree. C., and in the presence of a catalyst, the improvement which comprises employing as said catalyst a zinc, cadmium or mercury salt of an aliphatic carboxylic acid having 1-20 carbon atoms or a cycloaliphatic carboxylic acid having 4-20 carbon atoms.
In a process for preparing methylene-bridged diaryl isocyanates by reacting in an .alpha.-halomethyl aromatic compound with an aromatic isocyanate at a temperature in the range of from about 100.degree. to about 250.degree. C., and in the presence of a catalyst, the improvement which comprises employing as said catalyst a zinc, cadmium, or mercury salt selected from the group consisting of formate, acetate, propionate, butyrate, hexanoate, decanoate, laurate, palmitate, stearate, neodecanoate, naphthenate, cyclobutanecarboxylate, cyclododecanecarboxylate, and cyclohexaneacetate.
Dependencies are inferred from the claim text.