COATING COMPOSITIONS CONTAINING POLYISOCYANATES AND ASPARTATE-TERMINATED UREA/URETHANE PREPOLYMERS

摘要

The present invention relates to coating compositions containing a) 15 to 35% by weight, based on the weight of components a) and b), of aspartate-terminated urea/urethane prepolymers that are based on the reaction products of i) NCO prepolymers having a functionality of 1.8 to 2.2 and based on linear or branched aliphatic diisocyanates and ii) diaspartates prepared from linear or branched aliphatic diamines, b) 65 to 85% by weight, based on the weight of components a) and b), of diaspartate ii) and c) a polyisocyanate adduct prepared from aliphatic diisocyanates and having an average functionality of 2.8 to 3.1, wherein components a), b) and c) are present in amounts sufficient to provide an equivalent ratio of aspartate groups to isocyanate groups of 1.2:1 to 1.0:1.3. The present invention also relates to coatings prepared from these coating compositions.