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Quaternary ammonium derivatives containing a morpholinium moiety in the head group and exhibiting micelle-forming activity have been synthesized and characterized. These compounds exhibit poly-functional properties: they efficiently inhibit hydrogen sulfide and combined (H2S and CO2) corrosion of steel, are characterized by strong bactericidal activity against sulfate-reducing bacteria, and possess pronounced bacteriostatic and fungistatic effects.

Use of aqueous micellar solutions of dicationic surfactants with the general formula [R(CH3)2N(CH2)6N(CH3)2R]2+2Br− (R = n-C10H21 to n-C16H33) as the reaction medium for the alkaline hydrolysis of phosphonic acid esters has revealed a strong catalytic effect of the surfactants, which can increase the reaction rate by two orders of magnitude. This effect depends on the surfactant structure, shows itself at low surfactant concentrations, and is substrate-specific. The effect of the micelles on the phosphonate hydrolysis rate is largely determined by the hydrophobicity factor.

Tensiometry, dynamic light scattering, and optical spectrophotometry are employed to quantitatively characterize the aggregation behavior of a gemini (dicationic) surfactant in aqueous solutions in the presence of poly(ethylene glycol) with a molecular mass of 20000 Da or a Pluronic F127 block copolymer with a molecular mass of 12600 Da. It is shown that the formation of surfactant-polymer mixed aggregates decreases the positive surface potential of gemini surfactant micelles and is one of the main reasons for weakening of the micellar catalytic effect in hydrolysis of carboxylic acid esters.

The rate of carboxylic ester cleavage by amphiphilic low-molecular-weight and polymeric amines in the presence of polyoxyethylated calix[4]arenes with different degrees of oxyethylation is determined by the formation of mixed aggregates, by the shift of pK a of the amine, and the character of the distribution of the reactants in functional micelles. All of the systems show a high substrate specificity. In the case of octyl- and decylamines, the reaction of p-nitrophenyl acetate is catalyzed and the reaction of more hydrophobic p-nitrophenyl laurate is inhibited. An opposite situation is observed in the systems based on branched polyethyleneimine: the reaction of p-nitrophenyl acetate is inhibited and the process involving p-nitrophenyl laurate is accelerated.

The solubilizing action of micellar, microemulsion, and polymer-colloid systems formed on the basis of biologically compatible amphiphilic polymers and nonionic surfactants on capric, lauric, palmitic, and stearic acids was characterized quantitatively. Systems based on micelle forming oxyethyl compounds increased the solubility of fatty acids by more than an order of magnitude. Acid molecules incorporated into micelles increased their size and caused structural changes. Solubilization was accompanied by complete or partial destruction of intrinsic acid associates and an increase in their pK a by 1.5–2 units compared with water.