Storage-stable polyurethane encapsulation compound for embedding hollow fibers in the manufacture of filter elements

摘要

According to the present invention, a polyol component (A) and an isocyanate component (B) containing at least one aromatic isocyanate are mixed to obtain a reaction mixture, and the mixture is completely reacted to obtain a polyurethane-encapsulated compound. A obtainable polyurethane encapsulating compound for embedding hollow fibers of a filter element, wherein the polyol component (A) has a hydroxyl number of from more than 50 mg KOH/g to less than 500 mg KOH/g and of from 2 to 6. Functionalized at least one fatty acid-based polyol (a1) and bismuth carboxylate (a2-I) having at least one tertiary nitrogen atom and at least one isocyanate-reactive hydrogen atom. It contains at least one bismuth catalyst (a2) obtainable by mixing with an amine compound (a2-II), and the molar ratio of bismuth and amine compound (a2-II) is from 1:0.5 to 1. : 50. Further, the present invention relates to a method of making a filter element using a polyurethane encapsulation compound and to the use of the polyurethane encapsulation compound in embedding hollow fibers.