POLYISOCYANATE-BASED ADHESIVE

Various aspects of the present invention relate to a polyisocyanate based adhesive which is obtained by reacting an organic polyisocyanate with a compound containing isocyanate-reactive hydrogen atoms in the presence of a trimerisation catalyst. The organic polyisocyanate is a polymeric or prepolymeric polyisocyanate and the compound containing isocyanate-reactive hydrogen atoms comprises a polyol comprising a high ethylene oxide content, wherein the softblock content of the adhesive being between 40 and 60 wt%. The trimerisation catalyst is selected from the group consisting of tetraalkylammonium hydroxides, organic weak acid salts, trialkylhydroxyalkylammonium hydroxides, tertiary amines, metal salts of alkylcarboxylic acids, alkali metal salts of carboxylic acids, and combinations of two or more of these. The organic polyisocyanate and the compound containing isocyanate-reactive hydrogen atoms are miscible with each other and the compound containing isocyanate-reactive hydrogen atoms does not comprise an amine compound. L'invention porte sur un adhésif préparé par réaction d'un polyisocyanate organique avec un composé contenant des atomes d'hydrogène pouvant réagir avec un isocyanate en présence d'un catalyseur de trimérisation. La teneur en blocs mous de l'adhésif varie entre 20 et 70 % en poids.