二烷基乙氧基硫酸钠阴离子双子表面活性剂的合成及其表面活性

为研究阴离子双子表面活性剂结构与表面活性的关系,以不同碳链的脂肪醇、环氧氯丙烷、不同的二醇等为原料,通过三步反应合成出一种间隔基为乙氧基的阴离子双子表面活性剂二烷基硫酸钠,得到不同长度碳链和间隔基的4种双子表面活性剂,同时对部分合成条件进行了优化,确定了烷基单缩水甘油醚所用催化剂为苄基三乙基氯化铵以及烷基低聚二醇的最佳反应温度为80℃。核磁共振氢谱和傅立叶变换红外光谱证实了它们及其中间产品的结构。部分产品最小表面张力低于30 mN/m,临界胶束浓度低于0.1 mmol/L,具有良好的表面活性。实验表明,随着碳链的增长和间隔基长度的增加,其CMC降低,间隔基长度的增加使am in变大,但其γCMC变化不大。

Synthesis and Surface Activity of Anion Gemini Surfactant Dialkyl Ethoxylate Sodium Sulfate

Four kinds of ethoxy spacer anion gemini surfactants have been synthesized through the three-step reactions by different carbon chain fatty alcohol,epichlorohydrin,different short chain diol and other raw materials.The synthesis conditions were optimized and we chosen benzyl triethyl ammonium chloride as PTC,and the best reaction temperature is 80 ℃ in the second step.Structures of these Gemini surfactants and the inter-products were characterized by IR and ~1HNMR.The smallest surface tension of some products was lower than 30 mN/m,and their critical micelle concentration(CMC) was less than 0.1 mmol/L.It was shown these Gemini surfactants had good surface activities.As the lengths of hydrophobic chain increased and the lengths of spacer decreased,the CMCs decreased.With the lengths of spacer increased,the a_(min) increased,but it had little effect on their smallest surface tensions.