Patent ID: 8003745

Claim:
A process for preparing α-ethoxysilane modified polymers of the average general formula (Ib): in which R is a mono- to tetravalent polymer radical; not more than a third of the radicals R 1 , R 2 , and R 3 present in the polymer of the formula (Ib), independently of one another, are alkyl radicals having 1 to 4 carbon atoms; at least a quarter of the radicals R 1 , R 2 , and R 3 present in the polymer of the formula (lb), independently of one another, are ethoxy radicals; any remaining radicals R 1 , R 2 , and R 3 independently of one another are methoxy radicals; and n is 1 to 4; said process comprising reacting a compound of the formula R-X m , in which m is 1 to 4 and m =n and X is an isocyanate-reactive group, with at least one compound of the formula OCN—CH 2 —SiR 4 R 5 R 6 and at least one compound of the formula SiR 7 R 8 R 9 R 10 in the presence of one or more catalysts, where at least one of the radicals R 4 , R 5 , and R 6 is a methoxy radical and any further radicals R 4 , R 5 , and R 6 are alkyl radicals having 1 to 4 carbon atoms, and at least one of the radicals R 7 , R 8 , R 9 and R 10 is an ethoxy radical and any further radicals R 7 , R 8 , R 9 and R 10 are alkyl radicals having 1 to 4 carbon atoms.