Abstract: The flexible, resilient polyurethane foam is prepared by reacting at least one polyisocyanate with one or more liquid compounds which have at least two isocyanate reactive groups and at least one of which contain one or more solid polymers stably dispersed therein in an amount of 2.5 to 35 parts per 100 parts of said liquid isocyanate reactive groups containing compounds. The wet compression set of the flexible polyurethane foam could be considerably reduced by including in said liquid isocyanate reactive groups containing compounds, per 100 parts thereof, (I) 50 to 80 parts of one or more polyoxyalkylene polyols having an oxyethylene unit content of at least 40 wt. %, a hydroxyl number of between 20 and 100, and a nominal functionality of 2 to 4; and (II) 20 to 50 parts of one or more further polyoxyalkylene polyols containing no oxyethylene units or having an oxyethylene unit content lower than 40 wt. %, and having a hydroxyl number of between 20 and 100 and a nominal functionality of 2 to 4.

Abstract: The flexible, resilient polyurethane foam is prepared by reacting at least one polyisocyanate with one or more liquid compounds which have at least two isocyanate reactive groups and at least one of which contain one or more solid polymers stably dispersed therein in an amount of 2.5 to 35 parts per 100 parts of said liquid isocyanate reactive groups containing compounds. The wet compression set of the flexible polyurethane foam could be considerably reduced by including in said liquid isocyanate reactive groups containing compounds, per 100 parts thereof, (I) 50 to 80 parts of one or more polyoxyalkylene polyols having an oxyethylene unit content of at least 40 wt. %, a hydroxyl number of between 20 and 100, and a nominal functionality of 2 to 4; and (II) 20 to 50 parts of one or more further polyoxyalkylene polyols containing no oxyethylene units or having an oxyethylene unit content lower than 40 wt. %, and having a hydroxyl number of between 20 and 100 and a nominal functionality of 2 to 4.