| dc.description.abstract | In this work, multiple water-soluble polymer-surfactant systems were characterized utilizing the hydrophilic lipophilic deviation (HLD) and net average curvature (HLD-NAC) concepts. Water-soluble polymers utilized in this work include polydiallyldimethylammonium chloride (PDADMAC), hydroxypropyl cellulose (HPC), and polyvinyl alcohol (PVA). Although surfactant systems are extremely dynamic, this work aims to provide further understanding of the effects caused by the addition of water-soluble polymers to the optimal salinity of Winsor III microemulsions.
The optimal salinity for each system with differing concentrations of polymer was determined using coalescence rate and interfacial tension measurements. HLD characterization values, K and Cc, were analyzed for each polymer-surfactant system to provide insight to how the polymer was interacting within each system. PDADMAC and HPC were found to induce hydrophobic shifts in the optimal salinity of reference surfactant systems, while PVA induced hydrophilic shifts. Functions, f(P), corresponding to the HLD equation were found for each polymer-surfactant combination, allowing for the determination of the polymer-surfactant optimal salinity utilizing reference surfactant K and Cc values.
Changes in solution viscosity and solubilization abilities due to the addition of polymer were examined and compared with predictions from previous works based on expected charge interactions. In this study, viscosity noticeably increased only with the addition of PVA, and solubilization decreased with the addition of all polymers.
Emulsion droplet radii were found through dynamic light scattering experiments and compared to emulsion droplet radii predictions provided by the NAC model. NAC was then used to examine the hydrophilic surfactant head group area present within system middle phases. | en_US |
