甲酰胺与正负离子表面活性剂有序溶液的研究

Research on Molecular Organized Assemblies of Catanionic Surfactants in Formamide and Formamide/water Solution

对羧酸钠与烷基三甲基溴化铵1：1混合体系的研究表明：常温下各体系在不同比例甲酰胺（FA）／水混合溶剂中，表面张力随浓度变化均有明显的转折点，显示了混合体系中胶团的存在．实验中发现随混合溶剂中FA比例增加，各体系的临界胶团浓度（cmc）增大．在较高温度下发现在甲酰胺中亦存在着因胶团形成而产生的表面张力-浓度对数（γ－logc）曲线的转折点，利用相分离模型对体系胶团热力学参数进行了计算．并探讨了FA对正负离子表面活性剂囊泡的影响．

Molecular organized assemblies of 1:1 mixed solution of sodium alkylcarboxylatealkyltrimethylammonium bromide were investigated in formamide(FA) and FA/water mixtures.The critical micelle concentration(cmc) values of catanionic surfactants determined by the surface tesion curves increase as the fraction of FA in the mixed solvents increases. Above the Kraft point(~45°), micellization and surface adsorption properties of mixed surfactants in FA were studied. The cmc is 0.167,0.172 and 0.179mol-dm-3 for 50,55 and 60℃. The standard thermodynamic parmeters of micellization for catanionic surfactants in FA were calculated according to the model of charged pseudo-phased separation The influence of FA addition on catanionic surfactant vesicle was also studied.