Structural Study of a Eutectic Solvent Reveals Hydrophobic Segregation and Lack of Hydrogen Bonding between the Components

An in-depth study of the hydrophobic eutectic solvent formed by butylated hydroxytoluene (BHT) and l-menthol (MEN) in a 1:3 molar ratio has been carried out using an integrated approach that combines differential scanning calorimetry (DSC), attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy, small- wide-angle X-ray scattering (SWAXS), molecular dynamics (MD) simulations. The obtained data have step-by-step compared to those collected on 3,5-di-tert-butyltoluene (TBT) MEN same ratio, where TBT is analogous BHT without hydroxyl group. DSC characterization showed comparable results between two systems, evidencing group little or no impact thermal behavior BHT:MEN eutectic. Both FTIR MD agree finding hydrogen bond (H-bond) interactions are played because high steric hindrance suffered its so only established H-bonds molecules. incompatibility components terms formation segregation promoting MEN–MEN interactions, which even more intense than pure compound. three-dimensional arrangement remarkable degree structural order among alkyl functional groups, suggesting apolar–apolar attraction might be driving force formation. This picture translated into establishment intermediate-range organization solution, as evidenced SWAXS data. overall this pushing bit further definition these eutectics, indicated until now extensively H-bonded systems.