The Dow Chemical Company

The Upjohn Co.

Steven B Lowenkron

John L Nafziger

Charles E Koehler

Lao-Jer Chen

Rory D Daussin

Bruce N Stevens

Debkumar Bhattacharjee

Shenghong A Dai

Van A Kent

Richard A Prather

Howard R Steele

Rebond polyurethane foams can be prepared by coating shredded polyurethane foam with a prepolymer binder formulation which includes toluene diisocyanate distillation bottoms, compressing the binder coated foam, and the curing the binder with steam. The toluene diisocyanate distillation bottoms can be used in place of more expensive prepolymer formulation components such as toluene diisocyanate or methylene diphenyldiisocyanate. The toluene diisocyanate distillation bottoms can also improve elongation and tear resistance properties of the resultant rebond foams prepared therewith.

Flexible polyurethane rebond foam having improved tear resistance and

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

A viscosity-stable polyisocyanate prepared by heating a polyisocyanate containing uretone imine groups and a catalyst under reaction conditions sufficient to produce compounds containing 2-imino-4,6-dioxohexahydro-s-triazine groups is disclosed. The polyisocyanate product so prepared may be used alone or blended with other polyisocyanates or diisocyanates to produce polyurethane, polyisocyanurate, polyamide and related polymers. These polymers, when used to prepare a foam, may exhibit improved dimensional stability and flammability. Also disclosed is a family of isocyanate compounds containing at least one 2-imino-4,6-dioxohexahydro-s-triazine group and having an isocyanate functionality of at least 4.

Composition and method of preparation of viscosity-stabilized

A method of treating toluene diisocyanate distillation residues comprising reacting the residues with at least about 0.5 equivalents, based on hydrolyzable chloride concentration of the residues, of an epoxy compound at a temperature of from about 155 to about 220.degree. C. to produce a treated distillation residue having a hydrolyzable chloride level of less than about 800 parts per million (ppm) is taught. The product of the method is useful, for instance, in producing rigid foams with low K Factors.

Rigid foams prepared from treated toluene diisocyanate residue

Disclosed is an extraction process wherein a crude polyisocyanate is separated into a purified fraction and residual fraction wherein the purified fraction is characterized by greatly improved color over the crude material but with little or no difference in viscosity. The residual fraction remains perfectly useful for those applications where color is not a critical requirement. Significantly, the disclosed purification is achieved with literally a 100 percent material balance. No loss in polyisocyanate is encountered.

Color reduction of polymeric isocyanates via multiple solvent

Particle boards are currently prepared by treating the particles (e.g. wood chips) with a binder comprising an organic polyisocyanate and, optionally, a release agent and then subjecting the treated particles to a molding process involving heat and pressure. The resulting particle board will generally release well from the caul plates of the press after forming. However, it has been found that the ease of release is enhanced, particularly where the wood particles in the board are derived from hardwood, by utilizing a metal selected from magnesium and zinc in the metallic surfaces of the caul plates or platens which come into contact with the particle board during the application of heat and pressure.

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Houston, TX, United States of America

Steven B Lowenkron