The CMCs (critical micelle concentration ) of SDS (sodium dodecyl sulfate), sodium dodecylbenzenesulfonate (SDBS) in DMF at different temperatures were measured by using the conductivity method.The curve of ó-c was mapped to achieve a turning point in CMC; in accordance with the CMC.According to the thermodynamics principle, △Gmθ, △Hmθand △Smθwere obtained, which show that the CMC values in DMFsolvent are larger than the values in water.As the temperature increases, the CMC value is increased,△Gmθis reduced, and △Smθremained basically unchanged, with the endothermic phenomenon of micellar process.%利用电导法测定了SDS(十二烷基硫酸钠)和SDBS(十二烷基苯磺酸钠)在溶剂DMF(N,N-二甲基甲酰胺)中的临界胶束浓度cCMC.测定不同温度下表面活性刺的电导σ值,由σ-c作图的转折点求得cCMC;根据cCMC及热力学原理求得△Gθm,△Hθm及△sθm.结果表明:二者的cCMC值均大于水为溶剂时的cCMC值;随着温度的增加,cCMC增加,△Gθm减小,△Sθm基本保持不变,胶束过程伴随吸热现象.
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