Moisture-curing hotmelt adhesives comprising at least one silane-functional polyurethane prepolymer

A moisture-curing hotmelt adhesive composition comprising at least one silane-functional polyurethane prepolymer of the formula (I)

• where
• R1 is an n-valent organic radical of a prepolymer P,
• which is prepared from at least one polyol and at least one polyisocyanate and has at least n isocyanate groups,
• following removal of n isocyanate groups;
• R2 is an alkyl group having 1 to 10 C atoms;
• R3 is a linear or branched alkylene group having 1 to 10 C atoms;
• X is a hydrolyzable radical selected from the group consisting of
• where R′ is an aryl group and, if present, R″ is an aryl group;
• a is a value of 0, 1or 2;
• n is a value of 2 or more,
• the prepolymer P having a molecular weight of above 2000 g/mol, being solid at room temperature, and having no further silane group;
• wherein the silane-functional polyurethane prepolymer of the formula (I) is obtained from the reaction of a polyurethane prepolymer P having at least n isocyanate groups with a mercaptosilane of the formula (II):
• HS—R3—Si(X)(3-a)(R2)a (II).
• where X, R2 and R3 are defined as set forth above.