Helping Strands: Polyelectrolyte Assists in Surfactant Assembly below Critical Micelle Concentration.

Strongly adsorbing polymer/surfactant (P/S) combinations have been proposed for long-term applications such as emulsion stabilization. However, P/S systems are known to exhibit nonequilibrium behavior despite steady-state surface characteristics. This work examines the coadsorption of dodecyltrimethylammonium bromide and sodium poly(styrene sulfonate) (PSS) using oil/water tensiometry, UV absorption, and vibrational sum frequency spectroscopy.

Molecular Interactions Leading to the Coadsorption of Surfactant Dodecyltrimethylammonium Bromide and Poly(styrenesulfonate) at the Oil/Water Interface.

The strong synergistic adsorption of mixed polymer/surfactant (P/S) systems at the oil/water interface shows promise for applications such as oil remediation and emulsion stabilization, especially with respect to the formation of tunable mesoscopic multilayers. There is some evidence that a combination of dodecyltrimethylammonium bromide (DTAB) and sodium poly(styrenesulfonate) (PSS) exhibits the adsorption of a secondary P/S layer, though the structure of this layer has long eluded researchers. The focus of this study is to determine whether the DTAB-assisted adsorption of PSS at the oil/water interface occurs as a single layer or with subsequent multilayers.

Come Together: Molecular Details into the Synergistic Effects of Polymer-Surfactant Adsorption at the Oil/Water Interface.

The synergistic adsorption of polymers with surfactants at the oil/water interface has applications that range from oil remediation to targeted drug delivery. However, the inherent inaccessibility of the buried oil/water interface has challenged the development of a molecular-level understanding of the structure-function relationship of these systems. This study uses vibrational sum frequency spectroscopy to examine the molecular structure, orientation, and electrostatic effects of synergistic adsorption of the surfactant cetrimonium bromide (CTAB) and polymer poly(acrylic acid) (PAA) at a planar oil/water interface.

Molecular characterization of water and surfactant AOT at nanoemulsion surfaces.

Nanoemulsions and microemulsions are environments where oil and water can be solubilized in one another to provide a unique platform for many different biological and industrial applications. Nanoemulsions, unlike microemulsions, have seen little work done to characterize molecular interactions at their surfaces. This study provides a detailed investigation of the near-surface molecular structure of regular (oil in water) and reverse (water in oil) nanoemulsions stabilized with the surfactant dioctyl sodium sulfosuccinate (AOT).