Synthesis and Properties of a Novel Gemini Surfactant with Bis-piperidinium

A novel cationic Gemini surfactant with bis-piperidinium and benzene ring (C-10-CGP) was synthesized by aniline, epichlorohydrin and 1-bromodecane in three steps. The structure of C-10-CGP was characterized by mass spectroscopy (MS) and nuclear magnetic resonance (H-1 NMR). The critical micelle concentration (CMC) and the corresponding surface tension (gamma(CMC)) of C-10-CGP were measured from 298 K to 313 K and the thermodynamic parameters of the micellization were calculated. The results showed that the critical micelle concentration (CMC) and gamma(CMC) were 0.976 x 10(-3) mol . L-1 and 28.93 mN . m(-1) at 298 K, respectively. With the temperature increase, the CMC increased, the maximum surface adsorption capacity (Gamma(max)) decreased, the gamma(CMC) decreased and the minimum molecule area (A(min)) increased. The free energy of the system during the micelle formation was negative. When the Gemini surfactant was used as an asphalt emulsifier, C-10-CGP exhibited good a emulsifying ability. C-10-CGP is a slow-set asphalt emulsifier.