Use of low-unsaturated polyether polyols in foams for boards

The present invention discloses a method for the formation of a flexible slabstock polyurethane foam having substantially improved indentation force deflection and resilience characteristics while maintaining the other physical properties. The method comprises the steps of reacting a triol polyoxyalkylene polyether polyol having a plurality of internal blocks formed from oxyalkylene monomers with a plurality of terminal caps comprising ethylene oxide attached to said plurality of internal blocks, the internal blocks containing at least 80% by weight propylene oxide based on the total weight of all of the oxyalkylenes in said internal blocks and the amount of ethylene oxide in the terminal caps comprising from 5 to 25% by weight based on the total weight of the polyol, said polyol having a degree of unsaturation of less than or equal to 0.015 meq/g KOH with a polyisocyanate component in the presence of a catalyst and water as a blowing agent at a level of between 3 to 7% by weight.