Universal behavior of the apparent fragility and the structural relaxation time for the high pressure previtreous effect

Abstract: This report shows the universal previtreous behavior of the pressure related apparent fragility, i.e. the steepness index Basing on this finding, the 3-parameter relation for portraying the previtreous behavior of the primary (structural) relaxation time is derived. The fair portrayal of experimental data was shown for glass forming 8*OCB (liquid crystal), EPON 828 (resin) and diisobutyl phthalate, propylene carbonate (low molecular weight liquids). On decompressing, the dynamic crossover dynamic domains is clearly detected. All these recalls the mode-coupling-theory behavior, but for the pressure path. It is notable, the discussed description offers the fair portrayal of experimental data even in the extreme pressure range P up to 2.2 GPa.