Synthesis and Characterization of Novel Glyceline-based Low Transition Temperature Mixtures (LTTM) with L-Arginine

Novel low transition temperature mixtures (LTTM) based on three different mole ratio of hydrogen bond donor (HBD) in glyceline of (choline chloride: glycerol) 1:2, 1:3, and 1:4 with L-arginine (L-Arg) are successfully synthesized with different mole ratios between glyceline to L-Arg. The melting point of LTTM are not detected, however glass transition temperature are observed. The physical properties, such as density, viscosity, and refractive index of LTTM are measured at atmospheric pressure and temperature from (298.15 up to 343.15) K at an interval of 5K. The results showed that different mole ratio of HBD in glyceline, the mole ratio of glyceline to L-Arg, and temperature have great influences on both the physical and thermal properties of LTTM. Densities and viscosities of LTTM formed by glyceline and L-Arg decrease with increase temperature, but increase with increase of HBD and L-Arg mole ratio. The refractive indexes of LTTM decrease with increase temperature and HBD mole ratio but increase with decrease L-Arg mole ratio. The temperature dependence of densities and refractive indexes for LTTM are correlated by an empirical linear functions, and the viscosities are fitted using Vogel-Tamman-Flucher (VTF) equation and are found that R2 of all regression equations are 0.9999 and above