3851. Ethyl Silicate

Nomenclature

CAS number: 78-10-4
Silicic acid (H4SiO4) tetraethyl ester; silicon tetraethoxide; tetraethoxysilane; tetraethyl silicate.
C8H20O4Si; mol wt 208.33.
C 46.12%, H 9.68%, O 30.72%, Si 13.48%.

Description and references

Prepn from abs alcohol and silicon tetrachloride: J. J. Ebelmen, Ann. 57, 319 (1846); A. W. Dearing, E. E. Reid, J. Am. Chem. Soc. 50, 3058 (1928); G. Sumrell, E. E. Ham, ibid. 78, 5573 (1956). Toxicological studies: H. F. Smyth, J. Seaton, J. Ind. Hyg. Toxicol. 22, 288 (1940); V. H. Rowe et al., ibid. 30, 332 (1948). Review: H. D. Cogan, C. A. Setterstrom, Ind. Eng. Chem. 39, 1364 (1947).

Chemical structure

Properties

Colorless, flammable liquid. mp -77°. bp 165-166°. Flash point 125°F (52°C). d420 0.933; nD25 1.3818. Viscosity: 0.6 cP. Practically insol in water, and slowly dec by it. Miscible with alcohol.

Caution

Potential symptoms of overexposure are irritation of eyes and nose. See NIOSH Pocket Guide to Chemical Hazards (DHHS/NIOSH 97-140, 1997) p 142.

Use

In weatherproofing and hardening stone, arresting decay and disintegration; manuf weatherproof and acidproof mortars and cements. In the “lost wax” process for casting of high-melting alloys.