Abstract: A method for forming a product from cellulosic material and thermoactive material is described. A mat is formed from a mixture having cellulosic material and thermoplastic material. The mat is consolidated and pressed to a final thickness. At least a portion of a surface of the mat or product may be surface modified. Consolidating the mixture may include forming a first face layer, forming a core layer on the first face layer, and forming a second face layer on the core layer. Forming the core layer may include depositing mixtures of wood flakes and plastic flakes according to mixture flake size in successive layers such that the core layer has larger flakes adjacent the first face layer and adjacent the second face layer, and smaller flakes in a middle portion of the core layer. Consolidation can occur as a mat or composite moves through a hot-gas consolidation zone.

Abstract: Isocyanate prepolymers which are useful as binders are made from a polyisocyanate mixture and a hydroxyl compound having at least about 1 hydroxyl group. The polyisocyanate mixture is made up of from about 50 to about 60% by weight of polyphenyl polymethylene polyisocyanate and from about 40 to about 50% by weight of an isomeric mixture of diphenylmethane diisocyanate (MDI). The isomeric mixture of MDI is made up of from about 4 to about 30% by weight of the 2,4'-isomer and from about 70 to about 96% by weight of the 4,4'-isomer. The binders of the present invention are advantageous in that they may be used in high moisture, low temperature conditions without a catalyst. Reduced MDI emissions are also achieved when the binders of the present invention are used to make composite materials.

Abstract: The present invention is directed to a process for the production of a modified cellulosic product by:1) coating or impregnating a composition of:a) a polymethylene poly(phenyl isocyanate),b) water, andc) an organic compound having an hydroxy functionality of from 2 to 8, and having a molecular weight of from about 60 to about 8000, and being selected from the group consisting of i) ester group-free polyhydric alcohols, ii) polyether polyols and iii) mixtures thereof, and2) allowing the impregnated cellulosic material to cure at room temperature and without application of pressure.

Abstract: Disclosed herein is a stable fluid mixture and a binding composition containing the same; said mixture comprises a polyisocyanate and a solution of urea in water which is characterized in that the urea is premixed with water before it is admixed with the polyisocyanate to make a urea extended polyisocyanate.