Three novel amphiphilic dicephalic (double-headed) surfactants containing oligo(ethylene-oxide)methyl-ether and a sugar moiety TGA-m (m = 1, 2, and 3) that incorporate a tetrasiloxane at the terminus of a hydrocarbon chain were designed and synthesized. Their surface activity and aggregation behavior in aqueous solution were systematically investigated by surface tension, dynamic light scattering (DLS), and transmission electron microscopy (TEM) techniques at 298 K. The surface tension measurements provided the critical aggregation concentration (CAC) and the surface tension at the CAC (γ(cac)). In addition, with application of the Gibbs adsorption isotherm, the maximum surface excess concentration (Γ(max)) and the minimum surface area/molecule (A(min)) at the air-water interface were estimated. The effect of EO chain length on the surface activity and aggregation behavior was also investigated. It was found that both the γ(cac) and the CAC were lower than those for reported traditional hydrocarbon surfactants. Aggregates of three surfactants, TGA-m (m = 1, 2, and 3), formed in aqueous solutions could be assigned as spherical vesicles as suggested by analysis using DLS and TEM. Moreover the formation of vesicles can be confirmed by the encapsulation of bromophenol blue. These results indicate that these three surfactants have excellent efficiencies of vesicle formation and surface tension reduction in the aqueous phase.

Al-SBA-15 mesoporous molecular sieves with Si/Al ratio ranging from 50 to 15 were prepared and used for the catalysis of esterification of stearic acid with triethanolamine. The effects of Si/Al ratio and catalyst dosage on the esterification were investigated. Under the conditions of mass fraction of catalyst 0.25% and Si/Al ratio 25, the acid value of the product and content of monoesteramine plus di-esteramine in it were 1.78 mg KOH/g and 84.79%, respectively. From the result of reuse as catalyst, we knew that Al-SBA-15 showed very good stability during the esterification reaction. X-ray diffraction (XRD), nitrogen adsorption-desorption isotherms (BET), transmission electron microscopy (TEM), pyridine in situ FTIR characterization of the catalyst samples had been recorded. The results showed that Al-SBA-15 exhibited uniform channels, large surface area, and suitable acid strength.

A series of M/MgO (M = CaO, KNO 3 , KOH, K 2 CO 3 ) catalysts were prepared by a dry impregnation method and used for synthesis of glycerol carbonate from glycerol and dimethyl carbonate. It was found that K 2 CO 3 /MgO was the most efficient catalyst, with a glycerol carbonate yield of approximately 99% under the conditions: DMC/glycerol molar ratio 2.5:1, catalyst/raw material weight ratio 1%, reaction time 2 h, and reaction temperature 80°C. FTIR, BET, TEM, and XRD were used for characterization of the catalyst and showed that the active sites seemed to be K 2 O formed on the K 2 CO 3 /MgO catalyst. Finally, a recycling experiment showed that the catalyst was relatively stable and could be reused up to four times, at least, by regeneration.

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