NONTOXIC POLYETHOXYSILOXANE MATERIAL FOR THE PRODUCTION OF BIOLOGICALLY RESORBABLE AND/OR BIOACTIVE ARTICLES CONTAINING POLYETHOXYSILOXANE MATERIAL, THE PRODUCTION THEREOF, AND THE USE THEREOF.

摘要

The present invention relates to a polyethoxysiloxane (PES) material to be obtained in that (a) a first hydrolysis condensation reaction of a maximum of one group X of one or more different Si compounds of the formula (I) SiX4 (I) in which the groups X are the same or different and represent hydroxy, hydrogen, or ethoxy (EtO), are catalyzed in an acidic fashion at an initial pH value of 0 to ≤7, is conducted in the presence of ethanol (EtOH) or an ethanol-water mixture as a solvent over a time period of 1 to 24 hours at a temperature of 0°C to 78°C, (b) a second hydrolysis condensation reaction of the material obtained in step (a) is conducted while simultaneously removing the solvent by successive evaporation in a gas diffusion-tight container at a pressure of 100 to 1013 mbar, preferably at a slight negative pressure of 300 mbar to 800 mbar and a temperature of 50-78°C until a drastic increase in viscosity (at a shear rate of 10 s^-1 at 4°C) to 0.5 to 2 Pa.s until a constant weight is attained and a cyclotetrasiloxane of the general formula ((SiO(OH)0,75(OEt)1,25 x 1/64 H2O)4 and a molar mass of 4 * approx. 114 g = approx. 456 g; (c) said PES material is cooled in a closed container over a time period from a few minutes to a few hours, and (d) the PES material obtained from step (c) is converted into an rPES material by a third hydrolysis condensation reaction.