9194. Tetracosamethylhendecasiloxane

Nomenclature

CAS number: 107-53-9
Tetracosamethylundecasiloxane.
C24H72O10Si11; mol wt 829.76.
C 34.74%, H 8.75%, O 19.28%, Si 37.23%.

Description and references

Prepd by reaction of hexamethyldisiloxane with octamethylcyclotetrasiloxane and sulfuric acid: Patnode, Wilcock, J. Am. Chem. Soc. 68, 362 (1946); by cohydrolysis of ethoxytrimethylsilane and diethoxydimethylsilane: Hyde, US 2457677 (1948 to Corning Glass).

Chemical structure

Properties

Liquid; bp4.7 201°; bp0.5 152°; d425 0.9247; nD20 1.3994. Stable. Inert to most chemical reagents and rubber. Maintains about the same viscosity over a wide temperature range. Sol in benzene and the lighter hydrocarbons; slightly sol in alcohol and the heavy hydrocarbons.

Use

As a basis for silicone oils or fluids designed to withstand extremes of temperature; as a foam suppressant in petroleum lubricating oil.