US Patent 11859053 SiOC-bonded, linear polydimethylsiloxane-polyoxyalkylene block copolymers

Process for producing SiOC-bonded, linear polydimethylsiloxane-polyoxyalkylene block copolymers comprising repeating (AB) units, comprising pretreating acidified, end-equilibrated α,ω-diacetoxypolydimethylsiloxanes with a base and reacting the α,ω-diacetoxypolydimethylsiloxanes resulting therefrom with polyether diols in the presence of a solid, liquid or gaseous base, optionally using inert solvents.