Effect of carbohydrate based polymers on worm-like micelles of cetyltrimethylammonium p-toluenesulfonate in aqueous media: Detail physicochemical and antimicrobial properties survey

Abstract

Worm-like micelles of surfactant in presence of different polymers introduce very interesting properties of polymer-surfactant complexes. Physicochemical properties of interaction between oppositely charged polymer and surfactant are very complex process to study. Interaction between the cationic surfactant cetyltrimethylammonium p-toluenesulfonate (CTAT) forming worm-like micelle in aqueous solution and two different types of carbohydrate based polymers, anionic sodium carboxymethyl cellulose (NaCMC) and nonionic hydroxy ethyl cellulose (HEC) have been studied to compare the types of interaction in an aqueous medium. Polymer bound assemblies are formed when very strong binding of CTA+ monomers of CTAT to the anionic and nonionic sites of the polymer backbone starts because of electrostatic and hydrophobic interaction respectively, after a certain concentration of surfactant, abbreviated as critical aggregation concentration (cac). Electrostatic and hydrophobic effects interplay in the former (NaCMC-CTAT system), whereas the hydrophobic interaction is the ruling factor in the latter case (HEC-CTAT combination). Such types of interactions were supported from different techniques, viz. tensiometry, conductometry, turbidimetry, fluorimetry, time resolved fluorescence, and calorimetric measurements. Field Emission Scanning Electron Microscopy (FESEM) images have been taken of polymer-surfactant complexes for clear understanding the surface morphology and shape of the forming complexes. Antimicrobial activity of the formed polymer surfactant complexes has also been investigated.