A correspondence between Grunberg–Nissan constant d′ and complex varieties in water/methanol mixture

The aim of this study was to analyse the change in the complex structure formed in water/methanol mixture under temperature effect and/or mixture composition by a simple method. First, the dynamic viscosity of mixture was measured by rheoviscosimetry, and then the variation of the total activation energy versus methanol molar fraction was determined and discussed. The Grunberg–Nissan constant d′ was calculated in a large mixture composition and over the 20–40°C temperature range. By comparing the complex formulas in water/methanol mixture (H2O) m (CH3OH) n reported in literature at 20°C and the Grunberg–Nissan constant d′ variation versus methanol molar fraction X A, a correspondence between Grunberg–Nissan constant d′ and the complex varieties was established. According to this hypothesis, the change in the complex varieties for different temperatures was determined by showing a reduction of the complex varieties of water/methanol complex at high temperatures (35–40°C) in the mixture.