The Dow Chemical Company

Dow Global Technolgoies LLC

Rory D Daussin

Steven B Lowenkron

Etienne M Samson

John N Argyropoulos

Debkumar Bhattacharjee

Jorge Jimenez

John L Nafziger

Van A Kent

John L Maida

A method of preparing viscosity-stabilized toluene diisocyanate distillation residues comprising contacting toluene diisocyanate distillation residue with a material suitable for purging chloride-containing vapors under reaction conditions suitable to remove chloride-containing vapors from the toluene diisocyanate distillation residues. The material may be, for example, an aromatic solvent and/or a gas which associates, physically, chemically, or a combination thereof, with the vapors but not with significant amount of other components that may be present in the toluene diisocyanate distillation residue. The viscosity-stabilized and reactive residue can then be used alone or blended with one or more other isocyanate products, such as polymeric methylene diphenylisocyanate, to prepare materials such as polyurethane, polyisocyanurate, polyurethane-polyurea or polyurea compositions including, for example, foams.

Process for preparing viscosity-stabilized reactive toluene diisocyanate

Disclosed is a method for reducing hydrolyzable chloride in toluene diisocyanate (TDI) and, particularly, in TDI distillation bottoms, and polymers produced using the reduced hydrolyzable chloride bottoms. Crude TDI is heated, optionally in the presence of a solvent, to cause: (a) partial reflux, (b) partial reflux and fractionation, or (c) complete reflux and fractionation; under conditions sufficient to reduce hydrolyzable chloride. After distilling the crude TDI to form TDI monomer, the bottoms produced are thereby desirably reactive and viscosity-stable over a significant period of time. The treated bottoms can be reacted with compounds containing active hydrogen containing groups to form polyurethane, polyurea, and polyisocyanurate polymers, particularly foams.

Method for reducing hydrolyzable chloride in toluene diisocyanate

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Bellaire, TX, United States of America

Rory D Daussin