羧酸钠Gemini表面活性剂水溶液的表面活性及其pH影响  

Surface Activity of Sodium Carboxylate Gemini Surfactant Aqueous Solution and pH Effect

作　　者：杨新富 赵剑曦[1] 

机构地区：[1]福州大学化学化工学院应用化学系,福建福州350002

出　　处：《精细化工》2005年第6期436-439,共4页Fine Chemicals

基　　金：国家自然科学基金项目(20173010)~~

摘　　要：羧酸钠Gemini表面活性剂C11pPHCNa与相同烷烃链的月桂酸钠(SL)水解产生的酸式分子,使水溶液表面张力曲线呈现下凹状,电导曲线的转折点明显向较大浓度偏移(SL曲线),甚至消失(C11pPHCNa曲线)。添加10mmol·L-1NaBr仅表现出盐效应,不影响其水解。在临界的pH=8.2时,它们的水解影响被初步抑制,表面张力曲线表现出通常的上凸状。在pH=12时,CMC、c20和γCMC分别为9.30×10-2mmol·L-1、3.33×10-3mmol·L-1和35.4mN·m-1(C11pPHCNa)以及25.1mmol·L-1、5.37mmol·L-1和37.2mN·m-1(SL)。Sodium carboxylate gemini surfactant (C_~11pPHCNa) as well as sodium laurate (SL) produces the free carboxylic acid by hydrolysis in aqueous solution,resulting in the shape of the curve of surface tension (γ) against logarithmic concentration (logc) concaving downwards and the inflection point of conductivity plot moving towards larger concentration (SL case) compared with the result determined by surface tension,or disappearing as in C_~11pPHCNa case.Addition of 10 mmol·L^-1 NaBr only functions as salt effect,and has no influence on the hydrolysis of both surfactants. At the critical pH=8.2,the hydrolysis is preliminary restrained,and the plots of γ~logc show convex upwards as usual.At pH=12,the CMC,c_~20 and γ_~CMC are 9.30×10^-2 mmol·L^-1,3.33×10^-3 mmol·L^-1 and 35.4 mN·m^-1 (for C_~11pPHCNa) as well as 25.1 mmol·L^-1,5.37 mmol·L^-1 and 37.2 mN·m^-1 (for SL),respectively.

关 键 词：羧酸钠Gemini表面活性剂 表面活性 pH影响 

分 类 号：TQ423[化学工程]