Surface and Fluorescence Studies of Bis-Sulfosuccinate Anionic Gemini Surfactants Derived from Dodecanol Using Different Flexible Methylene Chains as Spacers

Abstract

AbstractAn effort has been made to synthesize, characterize and evaluate the fluorescence and surface active properties of dodecanol based bis-sulfosuccinate anionic gemini surfactants using α,ω-dibromo alkanes (BSGSLA1,4; BSGSLA1,6 and BSGSLA1,8). The chemical structures of the synthesized surfactants were confirmed by spectroscopic analytical techniques viz. elementary analysis, fourier transform infrared spectroscopy (FT-IR) and nuclear magnetic resonance spectroscopy (NMR). Numerous surface active properties viz. surface tension at CMC (ΥCMC), critical micelle concentration (CMC), efficiency of adsorption of surfactant (pC20), surface pressure at the CMC (πCMC), adsorption amount of surfactant (Γmax) and minimum area per molecule (Amin) were determined for synthesized surfactants. Low CMC value, larger pC20 consequently higher surface activity, higher Γmax value and lower Amin values for the surfactants with higher flexible spacer length [(CH2)8] were observed. The experimental data indicated that a gemini surfactant with a larger hydrophobic flexible spacer [(CH2)8] was more readily able to form micelles which leads to a lower CMC value, larger aggregation number, and a more closely packed micelle structure. The results also indicated that a greater aggregation number and a higher micropolarity can be achieved when concentration of gemini surfactants was increased.