Octafluorocyclobutane, or perfluorocyclobutane, C
4F
8, is an
organofluorine compound which enjoys several niche applications. Octafluorocyclobutane is a colourless gas and shipped as a liquefied gas. It is the perfluorinated analogue of
cyclobutane
Cyclobutane is a cycloalkane and organic compound with the formula (CH2)4. Cyclobutane is a colourless gas and commercially available as a liquefied gas. Derivatives of cyclobutane are called cyclobutanes. Cyclobutane itself is of no commercia ...
whereby all C–H bonds are replaced with
C–F bonds.
Production
Octafluorocyclobutane is produced by the dimerization of
tetrafluoroethylene
Tetrafluoroethylene (TFE) is a fluorocarbon with the chemical formula C2 F4. It is the simplest perfluorinated alkene. This gaseous species is used primarily in the industrial preparation of fluoropolymers.
Properties
Tetrafluoroethylene is a ...
and the reductive coupling of
1,2-dichloro-1,1,2,2-tetrafluoroethane.
[.]
Applications
In the production of
semiconductor
A semiconductor is a material which has an electrical conductivity value falling between that of a conductor, such as copper, and an insulator, such as glass. Its resistivity falls as its temperature rises; metals behave in the opposite way. ...
materials and devices, octafluorocyclobutane serves as a deposition gas and
etchant.
[{{cite web , url = http://encyclopedia.airliquide.com/Encyclopedia.asp?GasID=50#GeneralData , work = Gas Encyclopaedia , publisher = Air Liquide , title = Octafluorocyclobutane (RC318) , accessdate = May 15, 2013] It has also been investigated as a
refrigerant in specialised applications, as a replacement for
ozone depleting chlorofluorocarbon
Chlorofluorocarbons (CFCs) and hydrochlorofluorocarbons (HCFCs) are fully or partly halogenated hydrocarbons that contain carbon (C), hydrogen (H), chlorine (Cl), and fluorine (F), produced as volatile derivatives of methane, ethane, and pro ...
refrigerants. Exploiting its volatility and chemical inertness, octafluorocyclobutane may be found in some aerosolized foods. It is listed by the
Codex Alimentarius under number 946 (E946 for EU). It is investigated as a possible replacement for
sulfur hexafluoride as a
dielectric gas A dielectric gas, or insulating gas, is a dielectric material in gaseous state. Its main purpose is to prevent or rapidly quench electric discharges. Dielectric gases are used as electrical insulators in high voltage applications, e.g. transforme ...
.
References
Appendix
Its
critical point is at 115.3 °C and 2.79 MPa.
Perfluoroalkanes
Aerosol propellants
Refrigerants
Dielectric gases
Cyclobutanes