Vapor Pressure of Organophosphorus Nerve Agent Simulant Compounds

Abstract

The vapor pressures of four lower alkyl phosphonate compounds, dimethyl phosphonate (DMHP, CAS 868-85-9), dimethyl methylphosphonate (DMMP, CAS 756-79-6), diethyl methylphosphonate (DEMP, CAS 683-08-9), and diisopropyl methylphosphonate (DIMP, CAS 1445-75-6), have been measured by complementary methods that allow data collection at ambient and high temperatures by use of gas saturation and differential scanning calorimetry, respectively. Kosolapoff (J. Chem. Soc.195529642965) reported vapor pressure data above 200 Pa for several of these compounds measured by use of isoteniscope, although the lowest data points were deemed to be “not trustworthy” by the author. Our report extends the low end of the measured data range by 2 to 3 orders of magnitude in pressure. Antoine correlations, normal boiling temperatures, temperature-dependent enthalpies of vaporization, and volatility have been derived based on the measured data reported herein. The advantages of using complementary methodology and measuring, as opposed to extrapolating, data have been demonstrated in this work.

Raspberry Ketone Analogs: Vapour Pressure Measurements and Attractiveness to Queensland Fruit Fly, Bactrocera tryoni (Froggatt) (Diptera: Tephritidae)

“…Differential scanning calorimetry (DSC) has been used to determine the vapour pressure of diverse compounds, for instance, alkyl phosphonates [ 19 ], ethyl esters [ 20 ], 2-dialkyl aminoethanethiols [ 21 ], fatty acids [ 22 ] and precursors of chemical warfare agents [ 23 ]. In DSC, the isothermal boiling temperature of a pure compound is measured as a function of pressure.…”

Response Mechanism for Surface Acoustic Wave Gas Sensors Based on Surface-Adsorption

“…The saturated vapor pressure can be calculated by using the Antoine equation: $ln(P_0)=A-\frac{B}{C+T}$where P 0 is the saturated vapor pressure; A , B and C are empirical Antoine constants; T is the thermodynamic temperature. If P 0 in Pascal, the Antoine constants of DMMP [28] are A = 22.319, B = 4,344.0 and C = −51.7. In this work, the temperature of the SAW detector is controlled at 25 °C ( T = 298.15 K), substituting these parameters into Equation (10) we can get P 0 = 111 Pa.…”

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

“…6 Within the recommended ASTM pressure range down to 5 kPa, method uncertainty is + 1 K. At 1330 Pa, the larger pinholes yielded boiling points within 2 K of literature values. This decreased accuracy remains an area of further study.…”