Trimethylsilanol

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Trimethylsilanol
Structural formula of trimethylsilanol
Ball and stick model of trimethylsilanol
Names
Preferred IUPAC name
Trimethylsilanol
Systematic IUPAC name
Trimethylsilanol
Other names
Trimethylhydroxysilane
Identifiers
1066-40-6 YesY
ChemSpider 59498 YesY
EC number 213-914-1
Jmol-3D images Image
MeSH Trimethylsilanol
PubChem 66110
Properties
C3H10OSi
Molar mass 90.20 g·mol−1
Appearance Colourless liquid
Boiling point 99 °C (210 °F; 372 K)
Vapor pressure 21 mbar (20 °C) [1]
Related compounds
Related compounds
tert-Butanol

Silanol

Except where noted otherwise, data is given for materials in their standard state (at 25 °C (77 °F), 100 kPa)
Infobox references

Trimethylsilanol (TMS) is an organosilicon compound with the formula (CH3)3SiOH. The Si centre bears three methyl groups and one hydroxyl group. It is a colourless volatile liquid.[2]

TMS is used to apply hydrophobic coating on silicate surfaces. It reacts with the silanol groups of the substrate, coating the surface with a layer of hydrophobic methyl groups. A commercial example is Magic Sand.

Occurrence[edit]

TMS is a common contaminant in the atmospheres of spacecraft, where it arises from the degradation of silicone-based materials.[3] Specifically, it is the volatile product from the hydrolysis of polydimethylsiloxane, which are generally terminated with trimethylsilyl groups:

(CH3)3SiO[Si(CH3)2O]nR + H2O → (CH3)3SiOH + HO[Si(CH3)2O]nR

TMS and related volatile siloxanes are formed by hydrolysis of silicones-based containing materials, which are found in detergents and cosmetic products.

Traces of TMS, together with other volatile siloxanes, are present in biogas and landfill gas, again resulting from the degradation of silicones. As their combustion forms particles of silicates and microcrystalline quartz, which cause abrasion of combustion engine parts, they pose problems for the use of such gases in combustion engines.[4]

References[edit]

  1. ^ Grubb, W.T.; Osthoff, R.C.: Physical Properties of Organosilicon Compounds. II. Trimethylsilanol and Triethylsilanol in J. Am. Chem. Soc. 75 (1953) 2230–2232; doi:10.1021/ja01105a061.
  2. ^ Paul D. Lickiss "The Synthesis and Structure of Organosilanols" Advances in Inorganic Chemistry 1995, Volume 42, Pages 147–262 doi:10.1016/S0898-8838(08)60053-7
  3. ^ Trimethylsilanol, Harold L. Kaplan, Martin E. Coleman, and John T. James Spacecraft Maximum Allowable Concentrations for Selected Airborne Contaminants, Volume 1 (1994)
  4. ^ http://epics.ecn.purdue.edu/bgi/Documents/Fall%25202009/Removal_of_Siloxanes_.pdf