| 摘要 |
The present invention is directed to a process for the production of optionally cellular, polyurea elastomer moldings by reacting a mixture containing (I) a polyisocyanate component having an isocyanate content of about 10 to 30% by weight which comprises an isocyanate-terminated prepolymer prepared by reacting a polyisocyanate with a non-fatty, hydroxy polyester having a hydroxyl functionality of 1 to 4 and a molecular weight of about 500 to 4000, provided that if the hydroxy polyester is based on an aliphatic monocarboxylic acid, the aliphatic monocarboxylic acid is a non-fatty monocarboxylic acid containing less than 12 carbon atoms, (II) a polyether having at least two isocyanate-reactive groups and a molecular weight of 1800 to 12,000 in which at least 50% of the isocyanate-reactive groups are primary and/or secondary amino groups, and (III) abotu 5 to 50% by weight, based on the weight of component (II) of a chain extender comprising a sterically hindered aromatic diamine, the reaction mixture being processed as a one-shot system by the RIM process at an isocyanate index of about 70 to 130. The present invention is also directed to an isocyanate-reactive component for use in a RIM process based on components, (II), (III), (IV) and (V) and to an internal mold release agent mixture based on components (IV) and (V) and, optionally, (III). finally, the present invention is directed to the optionally cellular polyurea elastomers prepared by the above process.
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