High-precision measurements of the equation of state (EOS) of polymers at 100-1000 GPa using laser-driven shock waves*

The behavior of polymer materials at high-pressure ($>$100 GPa) is important for the design inertial-confinement-fusion capsules and the effect of stoichiometry at high-pressures. To address these we performed EOS measurements on polystyrene (CH), polypropylene (CH$_{2})$, and GDP (C$_{43}$H$_{56}$O) at shock pressures of $\sim $100-1000 GPa. These experiments use laser-driven shocks to drive impedance-match measurements using alpha quartz as a standard material. Shock velocities in these transparent samples \underline {and} the standard can be measured to $\sim $1{\%} or precision. This refines the impedance-match technique for laser-driven shock experiments to produce precise data at extreme pressures. A novel method for also acquiring re-shock data is presented. These data are compared to various EOS models and other experiments driven by gas guns and lasers.