Design and synthesis of an azobenzene-betaine surfactant for photo-rheological fluids was written by Butler, Calum S. G.;King, Joshua P.;Giles, Luke W.;Marlow, Joshua B.;Vidallon, Mark Louis P.;Sokolova, Anna;de Campo, Liliana;Tuck, Kellie L.;Tabor, Rico F.. And the article was included in Journal of Colloid and Interface Science in 2021.Application of 28322-40-9 This article mentions the following:
Morphol. of surfactant self-assemblies are governed by the intermol. interactions and packing constraints of the constituent mols. Therefore, rational design of surfactant structure should allow targeting of the specific self-assembly modes, such as wormlike micelles (WLMs). By inclusion of an appropriate photo-responsive functionality to a surfactant mol., light-based control of formulation properties without the need for additives can be achieved. A novel azobenzene-containing surfactant was synthesized with the intention of producing photo-responsive wormlike micelles. Aggregation of the mol. in its cis and trans isomers, and its concomitant flow properties, were characterised using UV-vis spectroscopy, small-angle neutron scattering, and rheol. measurements. Finally, the fluids capacity for mediating particle diffusion was assessed using dynamic light scattering. The trans isomer of the novel azo-surfactant was found to form a viscoelastic WLM network, which transitioned to inviscid ellipsoidal aggregates upon photo-switching to the cis isomer. This was accompanied by changes in zero-shear viscosity up to 16,000 x . UV-vis spectroscopic and rheo-SANS anal. revealed π – π interactions of the trans azobenzene chromophore within the micelles, influencing aggregate structure and contributing to micellar rigidity. Particles dispersed in a 1 wt% surfactant solution showed a fivefold increase in apparent diffusion coefficient after UV-irradiation of the mixture In the experiment, the researchers used many compounds, for example, Isopentyltriphenylphosphonium bromide (cas: 28322-40-9Application of 28322-40-9).
Isopentyltriphenylphosphonium bromide (cas: 28322-40-9) belongs to organobromine compounds. Bromo compounds are employed in a variety of metal-catalyzed coupling reactions. They are also ideal candidates for the synthesis of Grignard reagents that have wide-applicability in organic synthesis. In the pharmaceutical industry organo bromine derivatives are used as sedatives, vasodilators, antiseptic agents, and anticancer agents.Application of 28322-40-9
Referemce:
Bromide – Wikipedia,
bromide – Wiktionary