US Patent 7759423 Polymer polyols with ultra-high solids contents

The present invention relates to ultra-high solids content polymer polyols which have good filterability while maintaining a reasonable viscosity, and to a process for the preparation of these ultra-high solids contents polymer polyols. These polymer polyols comprise the free-radical polymerization product of (A) a base polyol, (B) a pre-formed stabilizer, (C) at least one ethylenically unsaturated monomer, (D) at least one free-radical polymerization initiator, and (E) at least one chain transfer agent. The solids contents varies from 60% to about 85% by weight.