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Tetraethyl orthosilicate is the ethyl ester of orthosilicic acid, Si(OH)4.
T 1413 (OTTO) Tetraethyl orthosilicate, 99.999% Cas 78-10-4 - used in semiconductor industry. T 1413 (OTTO) Tetraethyl orthosilicate, 99.999% Cas 78-10-4 - used as a cross linking agent in silicon polymers and in aerogel preparations.