Flexible polyurethane rebond foam having improved tear resistance and method for the preparation thereof
AssigneeThe Dow Chemical Company
InventorsJohn L. Nafziger, Steven B. Lowenkron, Charles E. Koehler, Bruce N. Stevens
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Abstract
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.
Claims14
A method for preparing a flexible polyurethane rebond foam comprising a first step of applying a binder prepared from a formulation including:
- (A) methylene diphenyldiisocyanate or polymethylene polyphenyl polyisocyanate;
- (B) toluene diisocyanate distillation bottoms;
- and
- (C) an active hydrogen containing material;
- to a shredded flexible polyurethane foam as a coating, and a second step of compressing the coated foam in the presence of steam for a period sufficient to bind the shredded foam.
Dependencies are inferred from the claim text.