GC2 PFT Analysis: User Guide
Rev. 376 | June 2018 – V.Percuoco
Draft 6/7/2011; Rev. 1/2/1014; Rev. 371T | July 2017 – D.Houpt
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Both perfluoromethyldecalin (PFMD) and perfluoromethylcyclohexane (PFMCH) are miscible in each other. The vapor pressure of PFMCH is fairly high so it evaporates readily and quickly at standard room pressure and temperature. The evaporation of PFMD is less significant. The low solubility in water for either compound facilitates gas-phase partitioning and quantitative headspace analysis.
The purity of PFMD purchased from Oakwood Chemical is approximately 85-90%. The predominant contaminants tend to be perfluorodecalin and perfluoro-tert-cyclohexane. The purity of a batch may be found by navigating to Oakwood Chemical's website 
, searching for "decalin" and entering the LOT # located on the bottle label.
https://www.oakwoodchemical.com/
A Note about the Relative Volatility of PFMCH and PFMD
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Both PFMCH and PFMD are considered to be non-hazardous by US and EU classifications under normal conditions.
Chemical Hazards:
- Incompatible substances: oxidizing agents, strong acids, strong bases
- Emits toxic fumes (HF) under fire conditions
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