abstract |
A process for preparing a dispersion of a filler e.g., melamine, urea or borax in a dispersion or graft polymer polyol is provided. The process comprises (1) dispersing the filler in a suitable basestock (e.g., a polyether polyol) and (2) thereafter using this as the basestock for preparing the dispersion or graft polymer polyol. n The polymer which is prepared in dispersed form in the second step may be for example (1) the reaction product of a polyamine, hydrazine or hydrazide and an isocyanate (PHD polymer) or (2) the reaction product of an olamine and an isocyanate (PIPA polymer). Alternatively styrene and acrylonitrile can be graft polymerised in the basestock in step (2). The new dispersion or graft polymer polyols containing dispersed filler are useful in the manufacture of fire resistant polyurethane foam for e.g., furniture applications. |