Density and rheology of tris(2-ethylhexyl) trimellitate (TOTM)

Abstract

This article presents new density data and some rheological studies on tris(2-ethylhexyl) trimellitate (TOTM) which has recently been proposed as a reference fluid for viscosity at high temperatures and high pressures. The density data have been obtained with the aid of an Anton Paar DMA HP U-tube instrument, covering temperatures from 328 to 423 K and pressures up to 70 MPa, and they are aimed at extending the temperature range of previous results. They are also used to check the effect of interlot consistency of the density data for TOTM. The presente density measurements are compared with previously published data. Rheological tests were carried out to complement earlier studies. Particular attention is given to the shear rate range of greatest interest for the proposed use of TOTM as an industrial reference fluid for viscosity: the tests include shear stresses up to 750 Pa and shear rates up to 4000 s−1 under atmospheric pressure. The tests were carried out using a Parallel Plate Rheometer AR1500ex10C4298. The results at a temperature of 298 K corroborate the previous findings that TOTM is Newtonian below a shear rate of 600 s−1, which is entirely compatible with its use as an industrial calibrating fluid for viscosity. At shear rates higher than 600 s−1 a shear-thinning like behavior is observed.info:eu-repo/semantics/publishedVersio