摘要 |
This invention is a polyurethane-urea elastomer which is the reaction product of a reaction mixture comprising (1) a liquid active hydrogen-containing composition which comprises a relatively high equivalent weight active hydrogen-containing compound, and an amine-terminated, relatively low equivalent weight compound, (2) a polyisocyanate which is present in an amount to provide about 0.8 to about 1.5 isocyanate groups per active hydrogen-containing group present in the mixture, and (3) a catalytically effective amount of a bismuth carboxylate catalyst. With the use of the bismuth carboxylate catalyst, excellent pot-life, yet rapid cures are achieved. In addition the so-called "green strength" of the elastomer, i.e., its physical strength at the time of its removal from the mold, is improved with the practice of this invention. Further, the post-cured elastomer exhibits excellent properties.
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