Stabilizing Colloidal Particles against Salting-out by Shortening Surface Grafts

Abstract

I I performed the syntheses of the particles grafted with mPEGA polymers of 5000 g/mol, as well as the particles with a polystyrene core. I performed the SAXS analysis, the DCP measurements of the former as well as the DLS measurements of both the former and latter. In addition, I did the cryo-EM image analysis and contributed to the discussion around it. I also wrote the "Crosslinked particles" section of the paper and part of the "Conclusions". Paper II I performed all of the synthesis work. I carried out the SAXS measurements with technical assistance and I analyzed some of the SAXS data using model fitting. I performed the DLS stability measurements of the new batches as well as for the LL25 batch. I wrote everything, except the part about the Flory-Huggins model for the stability, in a first draft of the paper. I contributed to the development of the Flory-Huggins model. Paper III I performed the synthesis, the majority of experimental planning, execution and interpretation of the results as well as most of the measurements, exception being the non-dialyzed particles in the pendant drop method and the Pickering emulsions. The SANS measurements were done with assistance. In addition, I wrote the first draft of the paper. Paper IV I performed the synthesis as well as all the sample preparations. I did the SAXS measurements together with the co-author with on-site techniqual assistance at the ESRF.

Effect of Electrolytes on Solution and Interfacial Behaviors of Double Chain Cationic–Nonionic Surfactant Mixtures for Hydrophobic Surface Wetting and Oil/Water Emulsion Stability Applications

“…This can be explained by considering two factors (i) the charge shielding effect of the polar headgroup and (ii) salting out effect of EO units in I-890 (EO-40), by the addition of electrolytes. Following the valency of the electrolytes (Cl – < SO 4 2– < PO 4 3– ), the energy required to lower the droplet size is less due to the dehydration of the surfactant mixture by salting out the EO chain, leaving its monomer to adsorb more at the oil–water interface. , Additionally, the electrolytes of similar ionic strength reduces the interfacial area between the oil and water phases, thus reducing the growth rate of oil droplets. This results in a smaller range of droplet sizes and forms a more stable emulsion with a nearly uniform droplet size distributions.…”

“…Anions on those cases enhance the association of water molecules and promotes water structure, and salt out the POE group responsible for reducing the cloud point and CMC. These anions include SO 4 2– , F – , PO 4 3– , OH – , and Cl – . − Thus, the investigation of the molecular behavior of mixed surfactant systems are not only important for a complete understanding of the surface energy mechanism, but are also essential in identifying specific application oriented technologies efficiently.…”

Synchrotron Scattering Methods for Nanomaterials and Soft Matter Research

“…The high brilliance of synchrotron X-rays has enabled studies of extremely dilute systems, such as aerosol suspensions [23], dusty plasmas [24], etc., and allowed obtaining the mean size and size distribution of primary particles as well as their aggregates and agglomerates. In sterically stabilized colloids, a systematic variation of surface grafts and their influence on the colloidal stability has been probed by USAXS [25], and, surprisingly, the shorter grafts were found to provide a better stability against the salting-out effect [26]. In concentrated systems, the interparticle interactions are significant, and the measured SAXS intensity becomes dominant of the structure factor, S(q), of interactions [5,22,27].…”