Abstract: The present invention provides a sulfur containing polyisocyanate polyaddition (PIPA) polyether polyol dispersion at a readily processible viscosity for use in making flexible polyurethane foams having inherent flame retardant properties that comprises a polyether polyol carrier and from 10 to 25 wt. %, based on the total weight of the dispersion, of particles of a sulfur containing polyisocyanate polyaddition (PIPA) polyether polyol having a particle size diameter (PSD), as determined by laser light scattering, of 90%, by volume, of the particles in the dispersion having a maximum PSD of from 0.2 to 4.5 am and that, further, contain two or more aromatic carbamate groups. The dispersion may further comprise water or a blowing agent, g) one or more catalysts; and f) one or more polyisocyanates in a foam forming mixture.

Abstract: Provides a silicon containing polyisocyanate polyaddition (PIPA) polyether polyol dispersion at readily processible viscosity for use in making flexible polyurethane foams having inherent flame retardant properties that comprises polyether polyol carrier and from 10 to 25 wt. %, based on total weight of dispersion, of particles of a silicon containing (PIPA) polyether polyol having a particle size diameter wherein 90%, by volume, of the particles in dispersion have maximum PSD of from 0.1 to 3 m and that, further, contain two or more aromatic carbamate groups. Dispersion may further comprise water or blowing agent, i) one or more catalysts, and f) one or more polyisocyanates in a foam forming mixture. In addition, provides methods for making the silicon containing PIPA polyether polyol dispersion comprising forming and mixing under shear a base polyol dispersion and delaying the addition of g) one or more polyisocyantes and h) a catalyst while mixing under shear.