| abstract |
A flexible polyurethane foam having improved sound absorbing properties in a low-frequency region. Also provided is a process for producing a flexible polyurethane foam which comprises foaming a starting-material composition (E) comprising one or more high-molecular polyoxyalkylene polyols (A), an organic polyisocyanate compound (B), a blowing agent (C), and a catalyst (D) in a closed mold, characterized in that at least part of the high-molecular polyoxyalkylene polyols (A) is a polyoxyalkylene polyol (a) having two or more hydroxy groups on the average and having a molecular weight per hydroxy group (Mc) of 1,800 to 2,800 and a total unsaturation value (USV) of 0.08 meq/g or less, and that the starting-material composition (E), when foamed so as to result in a thickness of 26 mm, gives a flexible polyurethane foam having an air permeability of 0.085 m3/min or less. |