双季铵基双肉豆蔻酸酯表面活性剂的合成及性能研究

Studies on synthesis and surface activity of gimini surfactant bismyristate containing two quaternary ammonium groups

以四甲基乙二胺、亚硫酰氯、肉豆蔻酸原料制备了乙撑双(二甲基)季铵盐双肉豆蔻酸酯(BQM),通过正交实验确定了最佳合成条件:以异丙醇作溶剂,α-溴代肉豆蔻酸甲酯与四甲基乙二胺的摩尔比为2.2∶1,反应温度为84℃,反应时间为8h。用IR,1HNMR和元素分析表征了BQM的结构。经测定BQM的临界胶束浓度(cmc)为3.5×10-4mol/L,表面张力(γcmc)为34.6mN/m。BQM与十二烷基磺酸钠(TLS)的复配体系在物质的量比为1∶2时,cmc降为5.0×10-5mol/L,γcmc为33.0mN/m,优于十二烷基三甲基溴化铵(DTAB)与TLS组成的复配体系。

Dimethylene-1,2-bis[dimethyl 1-（methoxycarbonyl）tridecyl ammonium bromide] （BQM） was synthesized by using N,N, N′,N′-tetramethylethylenediamine, thionyl chloride and myristie acid as feedstock. Through the orthogonal and parallel experiments, the optimal preparation conditions were determined as follows： using isopropanol as the solvent, molar ratio of methyl α-bromo myristate to tetramethylethylenediamine of 2.2：1, reaction time of 8 hours and reaction temperature of 84℃. The BQM structure was characterized by IR, 1HNMR and elementary analysis. The critical micelle concentration （cmc） of BQM was 3.5 ×10^-4mol/L and surface tension （γomc） was 34.6 mN/m. The composite system of BQM blended with sodium dodecyl sulphate （TLS） in molar ratio of 1： 2 had a cmc value of 5.0×10^-5mol/L and a γomc value of 33.0mN/m, showing better synergic effect than that of TLS blended with dodecyhrimethyl ammonium bromide （DTAB）.