MODIFIED, TRANSPARENT, AQUEOUS ALKALISILICATE SOLUTION, METHOD FOR THE PRODUCTION THEREOF AND THE USE THEREOF FOR THE PRODUCTION OF TRANSPARENT HYDROGELS.

摘要

The invention relates to a modified, transparent, aqueous alkali metal silicate solution, to a process for its preparation, and to its use for the preparation of transparent hydrogels. The alkali metal silicate solution according to the invention comprises an aqueous solution of one or more alkali metal silicates and optionally one or more water-soluble gelling agents and/or one or more water-soluble additives and is characterised in that it comprises from 3 to 70 % by weight, preferably from 10 to 50 % by weight, of one or more water-soluble silanols of the formula (I), optionally in precondensed form, YySi(OH)xR4-(x+y) (I in which the radicals Y and R are identical or different and have the following meanings: R is alkyl, alkenyl, aryl, alkylaryl or arylalkyl, Y is an organic ligand which is a polyhydric alcohol, an aminoalcohol, an aminothiol, a mercaptoalcohol, a diamine, a triamine or a dithiol and which is derived from an optionally substituted oxirane, thiirane or azirine or a hydrolytic ring opening, y is 1, 2 or 3, x is 1, 2 or 3, and x + y is /= 4. To prepare the transparent hydrogels, gelling agents are added to the alkali metal silicate solution according to the invention.