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: Novel adhesive, molding and binder compositions are formed from toluene diisocyanate residue which contains from about 12 to about 30% toluene diisocyanate and from about six to about twenty-five percent by weight of unreacted isocyanate groups.