| 摘要 |
The present invention relates to moisture-curable, polyether urethanes having terminal cyclic urea/reactive silane groups and containing a) 20 to 100% by weight, based on the weight of a) and b), of a polyether urethane containing two or more terminal cyclic urea/reactive silane groups and one or more polyether segments, wherein the polyether segments have a number average molecular weight of at least 3000 and a degree of unsaturation of less than 0.04 milliequivalents/g, provided that the sum of the number average molecular weights of all of the polyether segments per molecule averages 6000 to 20,000, and wherein the terminal cyclic urea/reactive silane groups are incorporated as the reaction product of an isocyanate group with an aspartate silane to form a urea group which is converted to a cyclic urea group in the presence of a catalyst and heat, and b) 0 to 80% by weight, based on the weight of a) and b), of a polyether urethane containing one reactive silane group and one or more polyether segments having a number average molecular weight of 1000 to 15,000. The present invention also relates to sealant, adhesive and coating compositions containing these polyether urethanes.
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