10.6084/m9.figshare.9532691.v1 Doudou Liu Doudou Liu Changfei Du Changfei Du Zhiyun Chen Zhiyun Chen Xue Wang Xue Wang Weiguo Shen Weiguo Shen The stability boundaries of droplets of water/AOT/Dynol-604/isooctane mixed microemulsions Taylor & Francis Group 2019 Density microemulsion volumetric property inter-droplet interaction stability boundary 2019-08-12 10:44:41 Journal contribution https://tandf.figshare.com/articles/journal_contribution/The_stability_boundaries_of_droplets_of_water_AOT_Dynol-604_isooctane_mixed_microemulsions/9532691 <p>In this study, we investigated the volumetric properties of water/sodium 1,4-bis(2-ethylhexyl)sulfosuccinate(AOT)/ethoxylated-2,5,8,11-tetramethyl-6-dodecyne-5,8-diol(Dynol-604)/isooctane mixed microemulsions by density measurement at <i>T</i> = 303.15 K. It was observed that the volumetric interaction between the microemulsion droplets decreased with the increase of the content of Dynol-604 due to the reduction of electrostatic repulsion between the AOT head groups. The volumetric properties were analyzed by a proposed thermodynamic model to obtain the critical microemulsion concentrations and the maximum molar ratios <i>ω</i> <sub>d,max</sub> of water to surfactants, which are the stable boundaries of the microemulsion droplets to accommodate the maximal content of water in their cores. It was found that <i>ω</i> <sub>d,max</sub> increased from 62 to 77 as the mole fraction of Dynol-604 in mixed surfactants varied from 0 to 0.5. This result is further confirmed by conductivity measurements.</p>