连接基长度对Gemini表面活性剂胶团间相互作用的影响  

Influence of Space Length on the Intermicellar Interaction of Gemini Surfactants

作　　者：吴章锋[1] 徐晓明[1] 张春艳[1] 韩国彬[1] 

机构地区：[1]厦门大学化学系固体表面物理化学国家重点实验室,厦门361005

出　　处：《高等学校化学学报》2004年第12期2299-2303,共5页Chemical Journal of Chinese Universities

基　　金：国家自然科学基金 (批准号 :2 9973 0 3 3 )资助

摘　　要：用电导率法和动态光散射法测定十二烷基三甲基溴化铵和季铵盐型 Gemini表面活性剂胶团的电离度和扩散系数 ,并结合 DLVO理论研究联接基长度和电解质浓度对胶团间相互作用的影响 .实验结果表明 ,联接基团长度会改变胶团电离度和胶团表面电荷密度 ,从而影响胶团间的相互作用 ,其影响程度主要取决于联接基的吸电子能力和 Gemini表面活性剂分子中两个带电基团的电荷重叠程度 ;电解质浓度对胶团间相互作用的影响可分为两种情况 :在低电解质浓度时 ,胶团间的相互作用以排斥力为主 ,不利于胶团的生长 ;而在高电解质浓度时 ,胶团间的相互作用以吸引力为主 。The method of conductivity was employed to determine the ionizability of the DTAB micelle and Gemini surfactants micelle and the method of dynamic lighting scatter was used to determine the diffusing coefficients of surfactants micelles. According to the DLVO theory, we discussed the influence of the spacer length and ionic strength on the intermicellar interactions. The results show that spacers have influence on the ionizability and density of charge of the micelles, and then affect the intermicellar interactions. The degree of the influence depends on the ability of attracting electrons of spacers and the charge′s overlapping degree of the two headgroups in the Gemini surfactants. The influence on the intermicellar interactions which was caused by ionic strength can be divided into two aspects: at a low ionic strength, the net intermicellar interactions is repulsive, and it is unfavorable to the growth of micelles; but at a high ionic strength, the net intermicellar interactions is attractive, and it is favorable to the growth of micelles.

关 键 词：GEMINI表面活性剂 胶团间相互作用 动态光散射 电离度 

分 类 号：O648[理学—物理化学]