NOVELTY - Composition comprises a chain-extended prepolymer, which is obtained from the reaction of (a) a polymer (I), (b) at least one polyisocyanate compound (II), at least one alkoxylated bisphenol as chain extender and (d) optionally an epoxide compound (III) containing a primary or secondary hydroxy group, or at least one epoxide resin A, which contains (III).    USE - The composition is useful as an impact resistor or as an A-component of a two-component epoxy resin composition, preferably two-component epoxide resin adhesive (claimed), which is useful for gluing in windmills.    ADVANTAGE - The composition can be economically produced with good adhesion properties and impact strength.    DETAILED DESCRIPTION - Composition comprises (A) a chain-extended prepolymer, which is obtained from the reaction of (a) a polymer of formula (I), (b) at least one polyisocyanate compound of formula (II), (c) at least one alkoxylated bisphenol as chain extender and (d) optionally an epoxide compound of formula (III) containing a primary or secondary hydroxy group, or at least one epoxide resin A, which contains (III).    X1 = O, S or NH;    Y1 = n-valent radical of a reactive polymer after the removal of terminal amino-, thiol-, or hydroxyl-groups;    Y2 = divalent radical of aliphatic, cycloaliphatic, aryl or araliphatic diisocyanates after the removal of isocyanate groups, or trivalent radical of trimers or biurets of aliphatic, cycloaliphatic, aryl or araliphatic diisocyanates after the removal of isocyanate groups;    Y3 = radical of aliphatic, cycloaliphatic, aryl or araliphatic epoxide containing primary or secondary hydroxyl group after the removal of epoxide groups and primary or secondary hydroxyl groups;    q = 1-3;    m = 1 or 2; and    n = 2-4, preferably 2 or 3.    An INDEPENDENT CLAIM is included for preparing the composition, comprising reaction of (a), (b), (c) and (d) in a first reactor to produce the chain-extended prepolymer, and discharging the prepolymer prepared in a deaerated and optionally dewatered charge, which contains an epoxy resin B, in a second reactor to give an impact resistor epoxy resin adhesive component.