阴离子双子表面活性剂分子结构对其溶液表、界面活性的影响

Effect of Molecular Structure on the Surface Activity and Interfacial Activity of Anionic Gemini Surfactant Solution

在合成一系列阴离子双子表面活性剂的基础上,使用表面张力仪和旋转滴界面张力仪考察了阴离子双子表面活性剂分子结构(亲水头基、疏水碳链、间隔基团)对其溶液表、界面活性的影响。研究发现,疏水链和间隔基团碳数相同时,磺酸盐双子表面活性剂具有更高的表面活性,羧酸盐双子表面活性剂的界面活性更高。间隔基团碳数相同时,随着疏水链碳数增加,双子表面活性剂的表面活性、降低溶液表面张力的能力、吸附效率均先上升后降低,界面活性升高。疏水链碳数相同时,随着间隔基团碳数增加,双子表面活性剂表面活性、降低溶液表面张力的能力、吸附效率均先上升后降低,界面活性降低。结果表明,阴离子双子表面活性剂分子结构的变化影响到其溶液的表、界面活性,在一定的条件下,调整阴离子双子表面活性剂分子结构可以使其溶液具有较为优异的表、界面活性。

Based on the synthesis of a series of anionic Gemini surfactants,the effects of the molecular structure(hydrophilic head group,hydrophobic chain and spacer group)of the anionic Gemini surfactants on the surface and interfacial activities of their solutions were investigated by surface tensiometer and spinning drop interface tensiometer.It is shown that when the number of carbons in the hydrophobic chains and the spacer groups is the same,the sulfonate Gemini surfactant has higher surface activity,and the carboxylate Gemini surfactant has higher interfacial activity.When the carbon number of the spacer groups is the same,with the increase of the carbon number of the hydrophobic chain,the surface activity,the ability to reduce the surface tension of solution and the adsorption efficiency of the Gemini surfactants first increase and then decrease,and the interfacial activity increases.When the number of carbons in the hydrophobic chains is the same,as the number of carbons in the spacer groups increases,the surface activity,the ability to reduce the surface tension of the solution,and the adsorption efficiency of the Gemini surfactants first increase and then decrease,and the interfacial activity decreases.The molecular structure of the anionic Gemini surfactants affects the surface and interface activity of their solution.Under certain conditions,higher surface and interface activity of anionic Gemini surfactant can be obtained by adjusting molecular structure.