| 摘要 |
Copolyesterpolyols comprising the equilibration product of at least two polyols manufactured by heating at least two high molecular weight polyols, at least one of which is a polyester polyol, to a temperature of 150 DEG to about 300 DEG C., preferably in the presence of a polyesterification and/or ester interchange catalyst, for a sufficient period of time to produce new copolyesterpolyols which have substantially constant melting points. Such copolyesterpolyols have approximately the melting point as the combination of the ingredients synthesized by a normal copolyesterification technique. Also provided are polyurethane products derived from the copolyesterpolyols comprising solid urethane elastomers, microcellular elastomers, flexible and rigid polyurethane foams, injection-molding resins, prepolymers and the like, prepared by reaction of the copolyesterpolyols with an organic polyisocyante and a chain extender.
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