| abstract |
The invention relates to a water-soluble or water-dispersible polyurethane which is the reaction product of A) at least one polyether polyol a1) having an average functionality of >= 3 and at least one urethane group-containing polyether polyol a2) having an average functionality of >= 4, B) at least one monoalcohol with 6 to 22 carbon atoms, C) at least one (cyclo)aliphatic and/or aromatic diisocyanate D) at least one oxime, monoamine and/or diamine with 2 to 18 carbon atoms, E) optionally at least one monoisocyanate with 4 to 18 carbon atoms, and F) optionally at least one polyisocyanate having an average functionality of > 2 wherein the starting NCO/OH equivalent ratio is between 0.5:1 to 1.2:1 having a particularly efficient thickening effect in the high-shear range, as well as their use for the thickening of aqueous systems. |