文档介绍：电导法测定阳离子型表面活性剂临界胶束浓度实验研究
【摘要】采用电导法测定一定温度下不同浓度的十四烷基三******化铵(TTAC),十六烷基三******化铵(CTAC),十八烷基三******化铵(STAC)溶液的电导率值,计算摩尔电导率,研究碳链上碳原子数对表面活性剂临界胶束浓度(CMC)的影响。结果表明:CMC(TTAC)=·L-1,CMC(CTAC)=·L-1,CMC(STAC)=·L-1,可知随着碳链上碳原子个数的增多,相应的临界胶束浓度(CMC)呈减小趋势。
【关键词】电导法;表面活性剂;临界胶束浓度;长碳链烷基季铵盐
Experimental study on the critical Micelle Concentration of Cationic Surfactant
With Conductivity Method
Abstract: Conductance method is used to determine a certain temperature under different concentrations of myristyl trimethyl ammonium chloride (TTAC), hexadecyl trimethyl ammonium chloride (CTAC), octadecyl trimethyl ammonium chloride (STAC) solution conductivity value, calculate the molar conductivity, the carbon number of carbon atoms in the chain of critical micelle concentration (CMC) of surfactant. The results showed that the CMC (TTAC) = mol·L-1, CMC(CTAC)=·L-1, CMC(STAC)=·L-1, known as the increasing of the number of carbon atoms of carbon chain, the corresponding critical micelle concentration (CMC) showed a trend of decrease.
Key words: conductance method; surface active agent; critical micelle concentration; long carbon chain alkyl quaternary ammonium salts.
由于表面活性剂溶液的表面张力、摩尔电导率、增溶作用等物理性质随着胶束的形成而发生突变,利用这些性质与表面活性剂浓度之间的关系,通过测定发生这些突变时的转变点,可推测出表面活性剂的临界胶束浓度(Critical Micelle Concentration, CMC)。CMC可以作为表面活性剂的表面活性的一种量度。因为CMC越小,则表示这种表面活性剂形成胶束所需浓度越低,达到表面(界面)饱