DENSITY AND VISCOSITY MEASUREMENTS OF 2,2,4-TRIMETHYLPENTANE (ISOOCTANE) FROM 198 K TO 348 K AND UP TO 100 MPA

New density and viscosity results for 2,2,4-trimethylpentane at temper atures from 198 K to 348 K and pressures up to 100 MPa are reported. T he measurements of both properties were performed simultaneously using a vibrating-wire instrument operated in the forced mode of oscillatio n. The present set of measurements extends those found in the literatu re to the high-pressure and low-temperature region. Correlations for b oth the density and the viscosity are presented, and comparisons are e stablished with various sets of results from the literature. The estim ated uncertainties of the results are +/-0.05% for the density and +/- 2.5% for the viscosity.