Lovis 2000m

The densities of the phases were measured precisely by a densitometer (Anton Paar®, DMA 5000) at 25 °C. The densitometer accuracy is 10⁻⁶ g cm⁻³. The viscosities of the phases were measured precisely by a microviscometer (Anton Paar®, Lovis 2000M) at 25 °C. The microviscometer accuracy is 10⁻³ mPa s. The dynamic interfacial tensions (IFT) were measured by an interfacial tensiometer (Krüss, DSA25) via the pendant drop method.^{32,33 (link)}

The dynamic viscosities of GILs, MeCN and their binary mixtures at atmospheric pressure from 283.15 to 333.15 K, with an interval of 5 K, were determined through an automatic microviscometer (Lovis 2000 M, Anton Paar, Graz, Austria) by using the rolling-ball principle, which is intended for determining the rolling time of a stainless steel or gold-covered ball in a liquid sample and calculating its viscosity from the rolling time. A ball rolls through a closed, liquid-filled capillary that is inclined at a defined angle. The liquid viscosity is directly related to the time obtained. Calibration was carried out by using deionized water or viscosity standard oils. The microviscometer can keep the temperature variation within ±0.01 K. This apparatus has the viscosity measurement range of 0.3–10 000 mPa s and the accuracy of up to ±0.5%. Each viscosity value is the average of three measurements at each temperature. The experimental viscosities of MeCN were compared with the literature values^{21–25 (link)} (see Table S1 in ESI†).