Shock compression data for liquids. I. Six hydrocarbon compounds

Abstract

Dynamic high pressure equation-of-state data are reported for 1,3- and 1,4-cyclohexadiene, cyclohexene, cyclohexane, toluene, and n-hexane initially in the liquid state. Plane shock waves generated by high explosives produced pressures of 0.5 to 43.0 GPa and densities to twice normal density. Toluene and n-hexane exhibit transformations at 12.6 and 19.0 GPa, respectively, but cyclohexadiene, cyclohexene, and cyclohexane do not. Decomposition of the molecule is the probable cause for the transition. Results indicate that reducing the number of double bonds by adding hydrogen pairs to the benzene molecule causes the transition to disappear. The shock velocity−particle velocity (us −Up) data for toluene, toluene, cyclohexadiene, and n-hexane are best represented by one or more line segments while cyclohexene and cyclohexane are fit by a quadratic in particle velocity. An extrapolation of the Us−Up curves to zero particle velocity result in a Us value for each liquid that is approximateley 40% higher than the bulk sound speed. The specific volume at a particular pressure for these liquids is ordered such that the hydrocarbon with the larger hydrogen-to-carbon ratio has a larger specific volume. This behavior is similar to that observed for other hydrocarbons.

High Pressure Photoinduced Ring Opening of Benzene

“…Benzene, a prototype of aromatic compounds, is, for its simplicity, an appealing system in both fundamental physics and chemistry and has been extensively investigated at high pressures. Different reaction products, hence different reaction paths, are reported in high pressure shock wave [9][10][11] and static experiments [1,[12][13][14][15][16][17][18]. This result is reasonable since the temperature and the compression time scale are very different in the two cases.…”

Shock-induced chemical reactions in simple organic molecules

“…Notable examples include works by Yakushev, et al for acrylonitrile [10], and Sheffield and Duvall for CS 2 [11]. The vast majority of reported shock-induced reactions are derived from cusps in the principal Hugoniot [12,13]. Dick examined shock-induced reactions in NH 3 , CCl 4 , benzene, toluene and a series of hydrocarbon ring structures, and noted "cusps" or non-linearities in the U s -u p data for many of the materials [12].…”

“…The vast majority of reported shock-induced reactions are derived from cusps in the principal Hugoniot [12,13]. Dick examined shock-induced reactions in NH 3 , CCl 4 , benzene, toluene and a series of hydrocarbon ring structures, and noted "cusps" or non-linearities in the U s -u p data for many of the materials [12]. The largest cusps were observed for benzene, toluene, and CS 2 , all of which experience large volume collapses during reaction.…”

“…Reactions may occur to form products that are more dense, e.g. polymerizations [7][8][9][10][11][12], less dense, e.g. detonation, or with no or little change in density (CCl 4 ) [11] along the reaction pathway.…”

Shock-induced polarization in normal-hexane

“…The time interval T 1 to T 3 also corresponds to the shock duration from the Hugoniot data for copper 12 and n-hexane. 13 At time T 3 a reflected wave propagates in the opposite direction thereby giving rise to negative polarization and consequently negative signal.…”