We report the synthesis and physiochemical characterization of a series of Natural Deep Eutectic Solvents (NADESs), a subclass of ionic liquids that have demonstrated their potential as green solvents for widespread commercial application, including bio-safe chemical engineering technologies. The novel NADESs comprise of hydrogen bond donating (HBD) (R)-3-hydroxyalkanoic acids (R3HAs), biodegradable monomers of renewable polymer polyhydroxyalkanoate (PHA), and an appropriate conjugate hydrogen bond acceptor (HBA) species; namely choline chloride (ChCl). We combined theoretical and experimental methods to characterize a series of NADESs with increasing content of R3Has. Gas-phase theoretical modelling provided insight on potential hydrogen bond interactions between the components of the novel NADES and facilitated interpretation of their IR and H NMR spectra. The experiments revealed that the viscosity of R3HA:ChCl NADESs increased with decreasing temperature and increasing fraction of ChCl. The viscosity-temperature dependence was best described by a polynomial relationship; the Vogel-Tamman-Fulcher (VTF) model was also used but did not represent the empirical data, suggesting R3HA:ChCl NADES's viscosity-temperature behaviour is of non-Arrhenius type. Similarly, density was shown to increase with decreasing temperature and increasing ChCl fraction. In contrast to viscosity, the bonding ratio change was found to have little effect on density at a fixed temperature, other than the proportional increase associated with a higher fraction of the denser component. Solubility and wettability investigations concluded that R3HA:ChCl NADESs are compatible with mildly polar and hydrophobic solvents and as a result have a polarity index in the range 0–4.1.

我们报告了一系列天然深共晶溶剂（NADES）的合成和理化特性，NADES是离子液体的一个子类，已经证明了它们作为绿色溶剂的潜力，可广泛用于商业应用，包括生物安全的化学工程技术。新型NADES由氢键给定（HBD）（R）-3-羟基链烷酸（R3HAs），可再生聚合物聚羟基链烷酸酯（PHA）的可生物降解单体和适当的共轭氢键受体（HBA）物种; 即氯化胆碱（ChCl）。我们结合理论和实验方法来表征一系列随着R3Has含量的增加而增加的NADES。气相理论模型为新型NADES的组分之间潜在的氢键相互作用提供了见识，并有助于解释其IR和H NMR光谱。实验表明，R3HA：ChCl NADESs的粘度随温度降低和ChCl分数的增加而增加。粘度-温度依赖性最好通过多项式关系来描述。还使用了Vogel-Tamman-Fulcher（VTF）模型，但不代表经验数据，表明R3HA：ChCl NADES的粘度-温度行为是非阿累尼乌斯类型的。同样，密度随温度降低和ChCl分数增加而增加。与粘度相反，发现固定比率下的键合比变化对密度几乎没有影响，除了与较高比例的致密组分相关的比例增加外。溶解度和润湿性研究得出的结论是，R3HA：ChCl NADES与轻度极性和疏水性溶剂兼容，因此极性指数范围为0-4.1。而不是与较高比例的致密成分相关的比例增加。溶解度和润湿性研究得出的结论是，R3HA：ChCl NADES与轻度极性和疏水性溶剂兼容，因此极性指数范围为0-4.1。而不是与较高比例的致密成分相关的比例增加。溶解度和润湿性研究得出的结论是，R3HA：ChCl NADES与轻度极性和疏水性溶剂兼容，因此极性指数范围为0-4.1。