Interactions of Hydrophobically Modified Polyelectrolytes with Nonionic Surfactants

Abstract

Interactions of surfactants with hydrophobically modified polyelectrolytes in aqueous solutions are important in several applications such as detergency, cosmetics, food, and paints. Complexes formed in these systems raise some fundamental questions about the polymer-surfactant interactions that control their behavior. In this work, the interactions of a nonionic surfactant, penta-ethyleneglycol mono n-dodecyl ether (C(12)EO(5)), with a hydrophobically modified anionic polymer, poly(maleic acid/octyl vinyl ether) (PMAOVE), in aqueous solutions were studied using surface tension, viscosity, electron paramagnetic resonance (EPR) spectroscopy, light scattering, and fluorescence spectroscopic techniques. When the nonionic surfactant C(12)EO(5) was added to aqueous solutions of the anionic polymer PMAOVE, it was incorporated into the hydrophobic nanodomains of PMAOVE far below the the critical micelle concentration (cmc) of the surfactant. Two inflection points were observed corresponding to the critical complexation concentration (formation of mixed micelles composed of C(12)EO(5) and the octyl chains of PMAOVE) and the saturation concentration (saturation of the polymer with C(12)EO(5) molecules). Above the saturation concentration, the coexistence of pure C(12)EO(5) micelles and mixed micelles of PMAOVE and C(12)EO(5) was observed. Such a coexistence of complexes has major implications in their performance in colloidal processes.

Structures of Langmuir-Gibbs Films Consisting of Long-Chain Fatty Acid and Water-Soluble Surfactants

“…Similar increases in surface tension have been reported in mixed systems of anionic polymer/anionic surfactants 30,31 , anionic polymer/ nonionic surfactants 32 , cationic polymer/anionic surfactants 33 , and cationic polymer/ mixture of anionic surfactant and nonionic surfactant 34 . The mechanism of the surface tension increase has been determined to be the incorporation of surfactant in micelles 30,31 , the incorporation of surfactant in nanodomains 32 and the complexation of surfactant and polymer 33,34 . However, these processes are not relevant to those in the present study.…”

Study on the interactions between SDBS/SOE‐60 mixed surfactant and PVP in solution

“…The binding and mixing surfactant micelles were formed by free SDBS and SOE‐60 molecules. The interactions of SDBS/SOE‐60‐PVP systems could be explained by the “necklace and bead” model . As the surfactant concentrations increase, small amounts of surfactant molecules continued to absorb at the air/water interface, so the surface tension subsequently decreased.…”

Interactions between DNA and Nonionic Ethylene Oxide Surfactants are Predominantly Repulsive

“…This behavior differs from, e.g., that reported by Deo et al with PMAOVE. 52 In mixtures of this polymer with C 12 E 5 , clear changes were observed in the surface tension plot due to the incorporation of C 12 E 5 into the hydrophobic domains of the polymer. 52 The results from the surface tension experiments are in accordance with the findings discussed in previous sections and the weak interaction between ss or dsDNA with the surfactant monomers, as the one with the surfactant aggregates, can be ascribed to the influence of the large headgroup that prevents the interaction between the surfactant tail and the hydrophobic domains of DNA.…”