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Ionic micelles are typically very affected by the salt concentration. In ionic micelles the monomers are typically fully ionized, but the high electric field strength at the surface of the micelles will cause adsorption of some proportion of the free counter-ions.
Micelles composed of ionic surfactants have an electrostatic attraction to the ions that surround them in solution, the latter known as counterions. Although the closest counterions partially mask a charged micelle (by up to 92%), the effects of micelle charge affect the structure of the surrounding solvent at appreciable distances from the ...
Micelles are composed of surfactant, or detergent, monomers with a hydrophobic moiety, or tail, on one end, and a hydrophilic moiety, or head group, on the other. The polar head group may be anionic, cationic, zwitterionic, or non-ionic.
A monomer is dispersed or emulsified in a solution of surfactant and water, forming relatively large droplets in water. Excess surfactant creates micelles in the water. Small amounts of monomer diffuse through the water to the micelle. A water-soluble initiator is introduced into the water phase where it reacts with monomer in the micelles.
The anionic character of the sulfate groups of SDS causes the surfactant and micelles to have electrophoretic mobility that is counter to the direction of the strong electroosmotic flow. As a result, the surfactant monomers and micelles migrate quite slowly, though their net movement is still toward the cathode. [3]
The aggregation number of micelles can be determined by isothermal titration calorimetry when the aggregation number is not too high. [ 2 ] [ 3 ] Another classical experiment to determine the mean aggregation number would involve the use of a luminescent probe, a quencher and a known concentration of surfactant.
In colloid science, a micellar solution consists of a dispersion of micelles (small particles) in a solvent (most usually water). Micelles are made of chemicals that are attracted to both water and oily solvents, known as amphiphiles. In a micellar solution, some amphiphiles are clumped together and some are dispersed.
In 2007, Ian Manners and Mitchell A. Winnik introduced this concept using a polyferrocenyldimethylsilane–polyisoprene diblock copolymer as the monomer, which assembles into cylindrical micelles. [23] When a fresh feed of the monomer is added to the micellar "seeds" obtained by sonication, the polymerization starts in a living polymerization ...