2, Formulaction, Toulouse, , France
Viscosity is an essential physical property when studying the rheological behavior. However, rheological studies remain a challenging task for many laboratories, as traditional techniques are time-consuming and faced to volatility and drying issues. In a new approach to confined, high shear viscosity measurements, a novel microfluidic rheometer is equipped with an enclosed system suitable for volatile and fast drying products, providing viscosity measurements as a function of shear rate and temperature in a single experiment set-up with an excellent precision and accuracy even at very low viscosity values. Visual analysis of a laminar flow interface generated from a reference and an unknown sample allows for viscosity to be measured by taking a picture of the main channel inside the microfluidic chip, using dedicated algorithms to automatically extract viscosity data over a controlled range of shear rates and temperatures. The technology allows flow viscosity measurements of liquid products from water-like to thick formulations using a small sample volume under a wide range of shear rates from 10 to 105 s-1. In this work, we have analyzed a model blend of two solvents aimed for Li-ion electrolyte batteries at 35 °C consisting of dimethyl carbonate, ethyl methyl carbonate and dissolved lithium salts.