Vapor Pressures of Some Phosphate and Phosphonate Esters

Abstract

80 70 60 50 40 9 0 10 20 30 40 50 60 70 80 90 100 2,4Dinitrotoluene, mole %.In a previous note' we reported that we were unable to duplicate the results of Stillwell and Robinson,2 who reported that the alloy commonly known as NarPb contains two formulas of Na31Pb8 in a face-centered cubic unit cell (a0 = 13.27 kX.) and is presumably one of the y-alloys with electron: atom ratio 21 : 13. I n every case our results (on alloy specimens prepared by ourselves) were in agreement with those of Zintl and Harder,a who reported four formulas of NaI6Pb4 in a body-centered cubic unit cell (a0 = 13.29 kx.). We concluded from our results and from some theoretical considerations that the results of Stillwell and Robinson are very probably in error.The alloy studied by Stillwell and Robinson was furnished by Dr. G. Calingaert (then of the Ethyl Corporation, Detroit, Michigan). Recently Dr. Calingaert has furnished us with a specimen of the same alloy prepared in the same way as that furnished to Stillwell and Robinson, and presumably identical to it in regard to structure. We have examined this alloy by powder photography, using the technique ,previously described' except that (1) D. P. Shoemaker, N. E. Weston and J. Rathlev, J . A m . Chsm.(2) C. W. Stillwell and W. K. Robinaon, {bid., 6S, 127 (1933).(3) E. Zintl and A. Harder, 2. physilc. Chem., B84, 238 (1936). SOC., 77, 4226 (1955).the powdered alloy was sealed in glass capillaries in the dry state rather than in oil. To test the remote possibility that in our previous work a phase transition from the S and R structure to the Z and H structure was brought about by grinding, a photograph was also taken of unground fines screened from the sample. To rule out the existence of the S and R structure at elevated temperatures, an additional powder photograph was taken with the specimen heated at 350" by a blast of hot air. All photographs showed only the Z and H phase, thereby confirming our previous results, and further substantiating the incorrectness of Stillwell and Robinson's results.We wish to thank Dr. Calingaert4 for his kindness in furnishing us wit,h the alloy sample, and the Ethyl Corporation (Baton Rouge, Louisiana) for financial support.In the course of a study of the lubricating properties of phosphates and phosphonates, we measured the vapor pressures of twenty of these and related compounds. Our results fit the Clausius-Clapeyron equation within the accuracy of our measurements. log P (in mm.:of Hg) = -A / T ("K.) + C The vapor pressures were measured from a few tenths of a millimeter up to atmospheric pressure or the thermal decomposition temperature. This is the temperature at which a compound begins to crack and give off more volatile fragments. It is marked by a break in the straight line on a graph of log P vs.

Occurrence and distribution of organophosphorus esters in soils and wheat plants in a plastic waste treatment area in China

“…S4, P < 0.005). What's more, most of the OPEs are nonvolatile to semi-volatile organic compounds (Dobry and Keller, 1957), and according to the previous studies they belong to the class of compounds that are easily drawn into the transpiration stream and be acropetally translocated within plants (Collins et al, 2006). However, we cannot exclude contribution from foliar uptake of OPEs from the air to their accumulation.…”

Determination of Polyparameter Linear Free Energy Relationship (pp-LFER) Substance Descriptors for Established and Alternative Flame Retardants

“… a At 25 °C, all experimental units for K wa were converted to [m 3 air /m 3 water ]. b Based on experimental water solubility and estimated vapor pressure. c Water solubility; vapor pressure d Water solubility; vapor pressure …”

Gas-liquid equilibrium of the hydrogen/bicyclohexyl system at elevated temperatures and pressures

“…The amount of bicyclohexyl in a sample is the sum of that in the weighed liquid and the relatively small amount which remains in the vapor at room temperature. The latter is accounted for using vapor pressure data of bicyclohexyl by Dobry and Keller (5). The amount of hydrogen in a sample is the sum of that in the gas phase plus that dissolved in the liquid.…”

“…Vapor pressure data on bicyclohexyl were taken from Dobry and Keller (5). The fugacity coefficients were determined from the Prausnitz and Chueh (8) modified Redlich-Kwong equation of state.…”

“…;_+, Olds et al, 1944 (13)\ X, Kay, 1940 (9); Í, Data et al, 1926 (7); X, Wackher et al, 1945, (19); Z, Laurance and Swift, 1974 (10)•, 0, Connolly, 1962 (6); , Hirata et al, 1969 (5); A.P.I. 44, 1974 (2).…”