VISCOSITIES OF CONCENTRATED NaCl-H2O AND Me2SO-NaCl-H2O SOLUTIONS AT SUBZERO TEMPERATURES

BACKGROUND: Viscosity is an important property of cryoprotectant solutions because it directly influences diffusion and reaction at liquid state. OBJECTIVE: To measure the viscosities of concentrated NaCl-H2O and Me2SO-NaCl-H2O solutions at subzero temperatures down to -50 degrees C. MATERIALS AND METHODS: Solution viscosity was measured with a rotary viscometer coupled with a thermostat bath. Two viscosity models, Laliberte model and Williams Landel Ferry (WLF) model, were employed in the correlation and prediction. RESULTS AND CONCLUSION: The Laliberte model performed well to correlate the viscosities of NaCl-H2O solutions measured here and the viscosities of Me2SO-H2O solutions found in the literature. The parameters obtained were used to predict the viscosities of Me2SO-NaCl-H2O solutions. The average discrepancy between the calculation and the experimental data was 19.0%. With the WLF model, the average discrepancy between the calculation and the experimental data for ternary solution was 5.4%.