Micelle ionic constituents

Discussion of Thermodynamic Behavior of the Ionic Constituents of Micelles in Mixed Solvents... 

Materials and Polymerization. Styrene and methyl methacrylate were obtained from commercial sources and were distilled to remove inhibitor. After distillation, the monomers were stored, under nitrogen, in a refrigerator. For the mixed emulsifier system, Emulphogene BC840(GAF), tridecyloxy-polyethylene-oxyethanol, was used as the nonionic constituent, and sodium lauryl sulfate (K and K Labs) was used as the ionic constituent. The sodium lauryl sulfate was at a concentration below its cms whereas the BD-840 was at a concentration above its cmc. This emulsifier system has been shown to yield mixed micelles (2)/ having a low ionic change (2)/ which produce latlces with rather narrow particle size distributions (2 ) ... 

Different molecules tend to form micelles of different shapes. For example, ionic species such as sodium dodecyl sulfate (SDS) and cetyl trimethylammo-nium bromide (CTAB) form rods at moderate concentrations, whereas sugar molecules form small, approximately spherical micelles. Broadly speaking, the shapes of micelles vary with the shape of the constituent molecules, their concentration, and the temperature. A useful predictor of the shape of the micelle, the surfactant parameter, N, is defined as... 

Riemersma [192] suggests that phosphate groups belonging to phosphoino-sitides, phosphatidic acid and other anionic lipids were involved in the ionic interaction of the surfactant head groups while the alkyl chain actually penetrated the membrane bilayer. At a certain concentration the membrane would form mixed micelles with the surfactant cations leading to higher permeability and cytolysis. However, both anionic and cationic surfactants induce lysis and their mode of action cannot be identical. Bradford et al. [194] examining the solubilization of microsomal constituents observed that both CTAB and... 

The amphiphilic copolymers in selective solvents self-assemble into nano-sized structures due to differences in the physicochemical characteristics of the constituent moieties. Spherical and cylindrical core-corona micelles as well as vesicles or polymersomes are the most commonly observed morphologies. Other morphologies such as toroids, bicontinuous, and multicompartment micelles, tubules, disk-like micelles, etc., are considered somewhat exotic. These stmctures are less frequently observed, however, they are not worth less than the commonly observed ones. The constituent moieties can be made sensitive to variations of parameters of the surrounding media such as temperature, pH, ionic strength, presence of specific additives/substances. 

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