Patent ID: 8206675

Claim:
A polyethoxysiloxane (PES) material obtained by (a) performing a first hydrolysis-condensation reaction (HCR) of an X radical of one or more different silicon compounds of formula I SiX 4 (I), where the X radicals are the same or different and each represent hydroxyl, hydrogen or ethoxy, acid catalyzed, in the presence of water and in the presence of ethanol or of an ethanol-water mixture as solvent, for a period of 1 to 24 h at a temperature of 0° C. to 78° C., (b) performing a second HCR of the material obtained in step (a) while at the same time removing the solvent by gradual evaporation in a gas diffusion tight container at a pressure of 100 to 1013 mbar, and a temperature of 50-78° C., until an increase in viscosity to 0.5-2Pa·s, until weight constancy and until formation of a cyclotetrasiloxane of the formula ((SiO(OH) 0.75 (OEt) 1.25 × 1/64 H 2 O) 4 and of molar mass of about 456 g; (c) cooling the polyethoxysiloxane material obtained in step (b) in a closed container over a period of from 2 to 5 minutes to 0.2 to 5 hours, to form a sol and, optionally; (d) converting the polyethoxysiloxane material obtained from (c) into an rPES material via a third HCR.