| 摘要 |
A high resilience (HR) polyurethane foam comprising the reaction product of (1) at least one polyisocyanate comprising at least about 5 weight percent of at least one methylene diphenyl diisocyanate isomer, derivative or a combination thereof and (2) an admixture of at least one natural oil based polyol and at least one additional polyol which is not a natural oil based polyol, wherein the admixture comprises at least about 10 weight percent natural oil based polyol and at least about 40 weight percent additional polyol having an equivalent weight of at least about 1700 Daltons; and the foam has a resiliency indicated by a ball rebound of at least 40 percent as measured according to the procedures of ASTM D 3574, Test H. An HR foam is made according to a process comprising steps of (a) forming a natural oil based polyol composition comprising at least about 10 weight percent of at least one natural oil based polyol having an OH functionality of at least about 2.2 and an equivalent weight of at least about 500 Dalton (Da) and at least about 40 weight percent of at least one conventional polyol having an equivalent weight of at least about 1700 Da and water; (b) admixing at least one catalyst with the natural oil based polyol composition to form a catalyst polyol admixture; (c) supplying a poly isocyanate comprising at least about 5 weight percent of at least one methylene diphenyl diisocyanate isomer, derivative or combination thereof in an amount corresponding to an isocyanate index of at least about 55 and at most about 105 and (c) admixing the isocyanate with the catalyst polyol admixture. The foams are useful in such applications as comfort, sound absorption including noise dampening, harshness dampening, protection, packaging, medical equipment, safety equipment and combinations thereof.
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