Aggregation of a pyrrolidinium surfactant in the presence of polymers and hydrotropes

Abstract

The functional properties (aggregation, solubilization, rheological) of a pyrrolidinium surfactant with a hexadecyl hydrocarbon tail and a hydroxyethyl moiety at the nitrogen (N) atom in the presence of polymers (poly(acrylic acid), poly(ethylene glycol) and poly(vinylpyrrolidone)) and hydrotropes (sodium salicylate, sodium benzoate and sodium tosylate) were investigated. It was established that the addition of sodium salicylate to an aqueous solution of a cationic surfactant leads to a sevenfold decrease in the critical micelle concentration and a four-order increase in solution viscosity. It was shown that the formation of mixed polymer–colloidal systems of the pyrrolidinium surfactant with uncharged polymers is expressed very weakly. In the case of poly(acrylic acid), it is determined by the value of its molecular mass: the greatest synergetic effect (the highest aggregating and solubilizing ability) is observed in the presence of a low-molecular-mass poly(acrylic acid).