Solution viscosity increase in fusion synthesis of Ca/Mg‐resinates

Abstract

AbstractThe effect of Ca/Mg‐resinate concentration on solution viscosity was studied in toluene. The viscosity was observed to increase drastically above a specific concentration value. The change in viscosity dependence on concentration implies a transition from a dilute to a concentrated regime, where viscous dissipation is governed by resinate molecular interactions and excluded volume effects. The concept of critical resinate concentration, ccrit, was applied and used to explain the nonlinear solution‐viscosity increase during the resinate synthesis. Ca/Mg‐resinates were synthesized by the fusion method at 265°C in a laboratory‐scale batch reactor. During the syntheses the increase in 50 wt. % toluene solution viscosity of the resinate turned almost exponential at a specific reaction time, denoted by t50. Based on the apparent reaction kinetics, a semiempirical model with two estimated parameters was derived for the solution viscosity to be used for the prediction of the t50, time of resinate syntheses.