Methods for producing a polymer with end groups of formula (I), which is free of isocyanate groups, wherein at least one hydrosilane of formula (II) is reacted with at least one polyurethane polymer containing isocyanate groups, where R1 stands for an alkyl group having 1 to 12 C atoms, R2 stands for a hydrogen atom or for an alkyl group having 1 to 12 C atoms, which optionally comprises ether oxygen or amine nitrogen, R3 stands for a linear or a branched alkylene or cycloalkylene residue having 1 to 20 C atoms, optionally with aromatic parts, and optionally with one or more heteroatoms, R4 stands for an alkyl group having 1 to 6 C atoms, R5 stands for an alkyl group having 1 to 10 C atoms, which optionally comprises one or more ether oxygens, n stands for 2 or 3 or 4, and x stands for 0 or 1.