METHOD OF IMPROVING MECHANICAL STRENGTH OF FLEXIBLE POLYURETHANE FOAMS MADE FROM BIO-BASED POLYOLS, THE POLYOL COMPOSITIONS UTILIZED THEREIN AND THE FOAMS PRODUCED THEREBY

A method of improving the mechanical strength of polyurethane foams made from bio-based polyols, the polyol-containing compositions utilized in the method of the invention, and the polyurethane foams produced by the method of the invention are provided. The method of the invention involves the incorporation of aromatic polyester polyol in the polyol-containing composition used to manufacture the foams. In one embodiment, the aromatic polyester polyol is utilized in a polyol-containing composition which is employed in the manufacture of flexible polyurethane foam. In another embodiment, the aromatic polyester polyol transesterified with a natural oil-containing composition to form a transesterification reaction product that is utilized in a polyol-containing composition which is employed in the manufacture of flexible polyurethane foam. Flexible polyurethane foams of the invention exhibit substantial improvements in mechanical strength properties, such as tear strength, tensile strength and elongation relative to foams made from bio-based polyols such as soybean oil-based polyols.