| abstract |
Silylated polyurethanes can be obtained by reacting at least one polyol compound having a molecular weight of 4000 to 20000 Daltons with a diisocyanate at a stoichiometric excess of the diisocyanate compound in relation to the polyol compound or the polyol compounds, thereby producing a polyurethane prepolymer which has isocyanate terminal groups; and then reacting the polyurethane prepolymer with one or more OH-terminated silanes of formula (1) to give a polyurethane having mainly terminal alkoxysilyl groups. In the formula (1), m = 0, 1 or 2, R1 represents an alkyl group with 1 to 4 carbon atoms, R2 represents an alkyl group with 1 to 4 carbon atoms, R3 represents a divalent organic group with 1 to 12 atoms selected from C, N and/or O in the chain, preferably however carbon atoms only, R4 represents a hydrogen atom or an alkyl group with 1 to 10 carbon atoms and R represents a difunctional organic group, preferably a linear or branched alkyl group with 1 to 6 C atoms. The silylated polyurethanes are suitable for use in a preparation as adhesive, sealing or coating agent. |