Relaxation, Viscosity and Density Scaling of the Hydrogen-bonded System Glycerol at Pressures above 5 GPa*

Using Tg(P) data for glycerol up to very high pressures of 6.7 GPa, we reanalyze viscosity and relaxation data taken by several groups over different temperature and pressure ranges, constraining these earlier data with our isochronous Tg(P) curve. This analysis allows new insights into the pressure dependence of fragility in such glass forming systems over pressure ranges in which the hydrogen bonded network is broken up. Attempts at thermodynamic scaling are also discussed for glycerol over this large pressure range.