Complexes of oil-soluble amphiphilic copolymers and low-molecular mass surfactants

Abstract

Complexation between anionic, cationic ionomers as oil-soluble amphiphilic copolymers and various oil-soluble surfactants proceeds in dilute ionomer solution in THF, m-xylene and chloroform with surfactant molecules of various degree of aggregation as well as with surfactant reversed micelles containing water. Sulfonated polystyrene or styrene-N-ethyl-4-vinylpyridinium bromide copolymers were used as ionomers, while sodium bis(2-ethylhexyl) sulfosuccinate, octadecyltrimethylammonium bromide, and primary aliphatic amines were used as surfactants. The formation of ionomer-surfactant complexes with well-defined limiting compositions () is established. The value of depends on the nature of the ionomer salt/acid group, the aggregation state of the surfactant, the type of low-polarity solvent, and the chemical nature of the surfactant. The character of the ionomer-surfactant complexation reaction and the structure of the new polymer-colloidal complexes are discussed.

Self-Assembly of Perfluorooctanoic Acid (PFOA) and PS-b-P4VP in Chloroform and the Encapsulation of PFOA in the Formed Aggregates as the Nanocrystallites

“…Self-assembly of block copolymers in solutions and the resultant polymeric nano-objects have attracted considerable interest in a great range of research fields of both theory and applications. − While, in most cases, the self-assembly occurs in a selective solvent due to the difference in the solubility between the two blocks, it can also be induced by interpolymer complexation. − In recent years, much attention was drawn to the complexation of a block copolymer with a small molecular surfactant and the self-assembly of the resultant complex. It was reported that the complexation in water could lead to the self-assembly of the complex forming vesicles, driven by the aggregation of the surfactant tails. , However, in a low-polarity organic solvent, the surfactant tails are soluble and the complexation usually increases the solubility of the block copolymer. , To our knowledge, no regular aggregates resulting from the self-assembly of such a complex in an organic solvent (or a solvents mixture) have been reported. In this article, we will report the self-assembly of the complexes of perfluorooctanoic acid (PFOA) and polystyrene- block -poly(4-vinylpyridine) (PS-b-P4VP) in chloroform.…”

“…12,13 However, in a low-polarity organic solvent, the surfactant tails are soluble and the complexation usually increases the solubility of the block copolymer. 14,15 To our knowledge, no regular aggregates resulting from the self-assembly of such a complex in an organic solVent (or a solVents mixture) have been reported. In this article, we will report the self-assembly of the complexes of perfluorooctanoic acid (PFOA) and polystyrene-block-poly(4-vinylpyridine) (PSb-P4VP) in chloroform.…”

Reverse micelles with spines: L2phases of surfactant ion—polyion complex salts, n-alcohols and water investigated by rheology, NMR diffusion and SAXS measurements

“…In stoichiometric mixtures these complex salts were molecularly dissolved in low-polarity organic solvents, but displayed ionomer type behavior, such as aggregation, when the surfactant ion was substituted by smaller ions in non-stoichiometric mixtures. In another report by the same group, 10 the studies were extended to a variety of polyelectrolytes and surfactants, which were found to produce interesting colloidal structures depending on the solvent properties or the chemical structures of the components, featuring properties such as solubilization of smaller molecules, stabilization of oil-in-water microemulsions and viscosity control in organic solvents. Two reports by Shioi et al 11,12 describe studies where a polycation could be dissolved in the L 2 phase of the anionic surfactant Aerosol OT mixed with n-hexane and water, and where polyacrylate similarly could be dissolved in an L 2 phase of the double-chained (didodecyl)dimethylammonium (DDA) cationic surfactant in cyclohexane and water, in both cases resulting in significant changes of the solution properties.…”

Self-Assembly of Formic Acid/Polystyrene-block-poly(4-vinylpyridine) Complexes into Vesicles in a Low-Polar Organic Solvent Chloroform

“…However, in low-polar organic solvents in which the nonpolar tails of LMC are soluble, the self-assembly leads to different results. 15,16 The block copolymers capable of forming complexes with LMC contain at least one block with a certain number of polar groups, so the binding with LMC usually increases their solubility in low-polar organic solvents. 16 Therefore, no regular aggregates resulting from the self-assembly of the complexes of LMC and block copolymers in organic solvents have been reported.…”

“…Since the relative amount of LMC and the binding are adjustable, Ikkala et al used the complexes to prepare materials with different morphologies and on−off properties in bulk. − In aqueous media , the self-assembly of the complex of LMC and a block copolymer may result in vesicles alone, , micellar clusters, or precipitation, depending on the dispersion state of the block copolymer in water before mixed with LMC. However, in low-polar organic solvents in which the nonpolar tails of LMC are soluble, the self-assembly leads to different results. , The block copolymers capable of forming complexes with LMC contain at least one block with a certain number of polar groups, so the binding with LMC usually increases their solubility in low-polar organic solvents . Therefore, no regular aggregates resulting from the self-assembly of the complexes of LMC and block copolymers in organic solvents have been reported.…”