一种新型阳-非两性双子表面活性剂的合成及评价

Synthesis and properties of a novel cationic-nonionic Gemini surfactant

摘要:

以脂肪醇聚氧乙烯醚和四甲基乙二胺为主要原料，经卤代、季铵化两步反应合成一种阳-非两性双子表面活性剂N,N’-乙撑双月桂醇聚氧乙烯醚二甲基氯化铵(DAEQ9-Cl)。卤代反应条件为：AEO-9/SOCl2=1/1.5（摩尔比），温度80℃，时间8h，吡啶作为催化剂，产率为87%；季铵化反应条件为：中间体/四甲基乙二胺=2:1（摩尔比），温度80℃，时间3d，产率为79%。产物结构通过红外、1H NMR得到证实。DAEQ9-Cl 的水溶液在25℃的cmc=3.2×10-2mmol/L，γcmc=33.44mN/m。DAEQ9-Cl与AEO-9复配表现出良好的协调效应，在最佳比n(DAEQ9-Cl) : n(AEO-9)=4:6 下体系的cmc=6.78×10-3 mmol/L，γcmc=28.5mN/m。具有较好的起泡性和稳泡性。

Abstract:

A novel type of cationic-nonionic gemini surfactant DAEQ9-Cl was synthesized with lauryl alcohol polyoxyethylene (9), dimethyl sulfoxide and tetramethylethylenediamine as the main starting materials. The main reaction includes chlorination and quaterisation. The optimum reaction conditions was ascertained as follows: n(dimethyl sulfoxide) : n(lauryl alcohol polyoxyethylene (9)) = 1.5 : 1, the reaction taking place at 80 oC for 8h, with pyridine as catalyst, the yield was 87%. In the quaterisation process, intermediate and tetramethylethylenediamine (2:1) reacted at 80 oC for 3d, the yield was 79%. The target product was identified by IR and 1H NMR. The critical micelle concentraton (cmc) is 3.2×10-2 mmol/L and γcmc is 33.44 mN/m at 25 oC in aqueous solution. DAEQ9-Cl shows a synergic effect when blended with AEO-9. The best compatibility effect was achieved at a molar of 4 : 6. The best compound system shows cmc=6.78×10-3 mmol/L, γcmc=28.5mN/m. This new surfactant exhibits higher foaming ability and foam stability.