Vapor Pressure of VX

Abstract

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Ambient Volatility of DMMP

“…Measured data included the mixture dew point temperature and ambient pressure. The methods and materials for measuring these parameters have been described in detail in previous reports [1,2]. Briefly, calibrated thermometers were used to measure bath temperatures and are believed to be accurate within 0.1 • C, and flow rates were measured using factory-calibrated electronic mass-flow controllers (Tylan General, San Diego, California).…”

“…The vapor pressures of dimethyl methylphosphonate (DMMP) [1] and a number of chemical warfare agents, e.g., O-ethyl-2-(isopropylaminoethyl) methyl phosphonothiolate (VX) [2,3] and cyclohexyl methylphosphonofluoridate (GF) [4], have been measured in the ambient temperature range recently. So far, that work has not included effects of atmospheric water vapor.…”

Selected Physical Properties of 2-Chloroethyl-3-Chloropropyl Sulfide (CECPRS)

“…Vapor saturation measurements were conducted using the apparatus described previously, 8 including a Hewlett Packard Model 5890 Series II gas chromatograph (GC) equipped with a flame ionization detector (FID) as described in detail in an earlier report from our laboratory. 9 The glass saturator used in this effort was custom designed at the U.S. Army Edgewood Chemical Biological Center (ECBC).…”

“…These readings were used in the vapor pressure calculation as described previously. 8 No corrections were included for the pressure drop between the sampling location and ambient. This correction is expected to be minimal because the flow stream was open to the atmosphere and there were no flow restrictions.…”

“…Calculation of vapor pressure from the indicated CECPRS mass associated with the measured FID area at each vapor pressure experimental temperature was performed as before. 8 Vapor pressure values are inferred from the measured data using Equation 2, as described elsewhere 8 and using the sample purity to correct the indicated vapor pressure by dividing by the CECPRS mole fraction (0.99) in accordance with Raoult's Law. This calculation assumes Ideal Gas Law behavior.…”