Abstract: Novel polymer/polyisocyanate compositions made by polymerizing at least one ethylenically unsaturated monomer in situ in a blend of a first organic polyisocyanate and a stabilizer. The stabilizer comprises a polyoxyalkylene polyol having a number average molecular weight of at least 4000; an isocyanato terminated prepolymer formed by reacting the polyoxyalkylene polyol and a second organic polyisocyanate with the proviso that the isocyanato terminated prepolymer and the first organic polyisocyanate provide greater than 25 equivalents of isocyanato groups per equivalent of hydroxyl groups; a polymer/polyol formed using the polyoxyalkylene polyol; a polymer/prepolymer formed using the polyoxyalkylene polyol with the proviso indicated for the prepolymer above; or a modified polyol containing an ester group formed using the polyoxyalkylene polyol.

Abstract: This invention relates to novel liquid polymer/polyol compositions consisting essentially of (1) a major amount of a polyol and (2) a minor amount of an acrylonitrile-vinylidene chloride polymer consisting essentially of (a) from 45 to 5 weight percent of polymerized vinylidene chloride and (b) from 55 to 95 weight percent of another polymerized monomer of monomers of which at least 20 weight percent is polymerized acrylonitrile, said weight percents being based on the weight of the polymer, and said polymer being in the form of particles that are stably dispersed in the polyol. The polymer/polyol compositions are prepared by a free radical catalyst initiated continuous process carried out at a temperature of 100.degree. C. or higher. The novel polymer/polyols are convertible to novel polyurethane products such as high resilience polyurethane foams having improved flammability characteristics.

Abstract: Novel improved polymer/polyol composition made by polymerizing one or more ethylenically unsaturated monomers in situ in a blend of a polyol having a number average molecular weight of at least about 76 and a preformed polymer/polyol prepared by the in situ polymerization of one or more polymerizable ethylenically unsaturated monomers in a polyol, said preformed polymer/polyl having a viscosity of not more than 40,000 cps at 25.degree. C., to form a highly stable dispersion of small polymer particles in said polyols, wherein said preformed polymer/polyol and said improved polymer/polyol composition are more stable than the polymer/polyol having the same chemical composition as said improved polymer/polyol composition but made in the absence of said preformed polymer/polyol. The novel compositions are highly useful in the production of polyurethane products.