Relationship between structure and biodegradability of gemini imidazolium surface active ionic liquids

Three ester-containing gemini imidazolium surface active ionic liquids [1,4-bis(1-alkyl-oxypropyl-imidazolium)-butane dichloride], abbreviated as [peCnBim2]Cl2 (n = 12, 14, 16), were synthesized from imidazole, 1,4-dibromobutane, 1-chloro-3-propanol, and various aliphatic carboxylic acids. Chemical structures of [peCnBim2]Cl2 were confirmed by H-Nuclear magnetic resonance, Fourier transform infrared spectroscopy, and elemental analysis. Thermal properties of [peCnBim2]Cl2 were studied with Thermogravimetric analysis and Differential scanning calorimetry. The micellization parameters, adsorption/aggregation properties, and thermodynamic parameters of [peCnBim2]Cl2 were demonstrated using tensiometry, electrical conductivity. Critical micelle concentration values of [peCnBim2]Cl2 aqueous solutions decreased with increasing the alkyl chain length (from C12 to C16). The formation of micelles was spontaneous, exothermic, and entropy-driven.