Title: Tetracosamethylhendecasiloxane
CAS Registry Number: 107-53-9
CAS Name: Tetracosamethylundecasiloxane
Molecular Formula: C24H72O10Si11
Molecular Weight: 829.76
Percent Composition: C 34.74%, H 8.75%, O 19.28%, Si 37.23%
Literature 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).
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.
Boiling point: bp4.7 201°; bp0.5 152°
Index of refraction: nD20 1.3994
Density: d425 0.9247
Use: As a basis for silicone oils or fluids designed to withstand extremes of temperature; as a foam suppressant in petroleum lubricating oil. |