Aggregation number of ionic surfactants and its application for alkyltrimethyl ammonium bromides and sodium tetradecyl sulfate by potentiometric technique

摘要

A potentiometric technique based on surfactant ion selective electrode has been used for various cationic and anionic surfactants. The data obtained contain m_1 (surfactant monomer concentration); m_2 (free counterion concentration) and α (degree of dissociation of micelle) were used for determination of aggregation number at and above cmc (critical micelle concentration). Data fitting show a relationship between aggregation number with such parameters. The correlation equation obtained shows that size of ionic micelle vary sharply after cmc. Also, the equation obtained shows size of micelle growth with increase in counterion concentration.