High-pressure viscosity prediction of di(2-ethylhexyl) phthalate and tricresyl phosphate binary mixtures using dielectric relaxation data

Dielectric permittivity and loss in di(2-ethylhexyl) phthalate and tricresyl phosphate binary mixtures were measured over a frequency range from 100 Hz to 1.5 MHz under high pressure. The mixtures showed single dielectric relaxation. The composite plots of the dielectric loss data showed one master curve and time–temperature–pressure superposition were applicable. The prediction of high-pressure viscosity was carried out from the change of dielectric relaxation time with temperature and pressure. The predicted results showed relatively good agreement with viscosity data obtained from a falling-sphere viscometer.