Abstract:

A cationic Gemini asphalt emulsifier with benzene ring(symbolized as G-T) was synthesized with aniline, epichlorohydrin and N,N-dimethyltetradecylamine by two steps. The product was characterized by Fourier transform infrared spectroscopy(FT-IR), mass spectroscopy, and proton nuclear magnetic resonance(¹H NMR) spectroscopy. The Krafft point, emulsifying power and performance of emulsified asphalt were studied. The critical micelle concentration(cmc) and surface tension(γ_cmc) of G-T were measured from 25 ℃ to 40 ℃ and thermodynamic parameters of the micellization were calculated. The results show that the Krafft point of G-T is below 0 ℃, and the stable time of the emulsified liquid is up to 309 s. The cmc and γ_cmc are 1.269×10^-3 mol/L and 38.33 mN/m at 25 ℃, respectively. With the rise of temperature, the cmc increases, the γ_cmc decreases, the maximum surface adsorption capacity(Γ_max) decreases and the minimum molecule area(A_min) increases. Emulsified asphalt test shows that G-T is a slow-crack asphalt emulsifier. The prepared emulsified asphalt meets the technical specifications of micro-surfacing.

Key words: Gemini surfactants, surface tension, emulsifying properties, asphalt emulsifie