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Interaction of polystyrene-block-poly(ethylene oxide) (PS-b-PEO) with cationic and anionic surfactants was studied using light scattering, sedimentation in ultracentrifuge, and ¹H NMR. The complex structure of the mixed solution containing hybrid micelles, micellar clusters, and supermicellar aggregates was confirmed by independent experiments. By proton NMR, addition of anionic surfactant, sodium dodecyl sulfate (SDS), to PS-b-PEO solution results in loosening the micelle cores and an increase of the PS molecular mobility in the presence of surfactant. At the same time, incorporation of SDS into the block copolymer solution leads to noticeable broadening of the signals related to methylene protons of the surfactant, which can be assigned to a decrease of mobility of surfactant alkyl chains “immobilized” on the PS cores. These data along with ultracentrifugation of hybrid solutions containing PS-b-PEO and surfactant at various concentrations prove that comicellization occurs and mixed micelles are formed. However, this phenomenon is observed up to a certain limiting concentration of the surfactant. In the case of cetyl pyridinium chloride (CPC), increase of surfactant loading up to 0.05 mol/L results in the solutions containing CPC micelles along with hybrid micellar clusters and supermicellar aggregates.

The interaction of the amphiphilic block copolymer, polystyrene-block-poly(ethylene oxide) (PS-b-PEO), with cationic surfactant, cetylpyridinium chloride (CPC), in aqueous media was studied by static light scattering and analytical ultracentrifugation. Three well-defined populations of hybrid structures corresponding to micelles, micellar clusters, and supermicellar aggregates were found to exist in the PS-b-PEO/CPC aqueous solutions at a block copolymer concentration of 10 g/L. The relative ratio of each type of structure and their parameters strongly depend on the CPC concentration, mobility of the polystyrene micellar core, and chemical composition of the dispersing media. Ion exchange of the surfactant counterions in the hybrid PS-b-PEO/CPC system by PtCl6^2- and PdCl4^2- ions resulted in saturation of the micellar structures with noble metal ions. The subsequent reduction of the metal-containing PS-b-PEO/CPC/MXn species with NaBH4 and molecular hydrogen resulted in the formation of metal nanoparticles mainly located in the block copolymer micelles.

The conditions are determined, in which the formation of polyterephthalate of phenolphthalein is accompanied by the liquid‐liquid phase separation of the reaction mixture. The kinetic parameters of the process and their connection with molecular mass characteristics of the reaction products are determined in some solvent‐nonsolvent systems. A mathematical model obtained early by the authors is used. It was observed that with increasing phase separation selectivity the influence of heterogeneity of the process on the MMD of the products becomes stronger. Am Beispiel der Bildung von Poly(phenolphthalein‐terephthalat) werden die Bedingungen ermittelt, bei denen die Polykondensation von einer Phasentrennung des flüssigen Reaktionsgemischs begleitet wird. Ferner wird die Kinetik des Prozesses für eine Reihe von Lösungsmittel/Fällungsmittel‐Systemen und ihr Einfluß auf die Molmassenverteilung der Reaktionsprodukte untersucht, wozu ein früher vorgeschlagenes mathematisches Modell benutzt wird. Schließlich wird gezeigt, daß mit zunehmender Selektivität der Phasentrennung der Einfluß des Heterophasencharakters des Prozesses auf die Molmassenverteilung der Reaktionsprodukte größer wird.

Linear polystyrene of Mw = 330 000 and Mw/Mn = 1.04 in which 50% and 100% of the phenyl residues were chloromethylated were heated in a 0.5 g/L ethylene dichloride solution in the presence of SnCl4 to convert them into an intramolecularly hyper-cross-linked soluble material. The spherical macromolecular species obtained exhibit low density and high surface area (up to 1000 m²/g) and swell strongly in all nonsolvents for linear polystyrene. Solutions in good polystyrene solvents exhibit low viscosity and reduced partial specific volume, but exceedingly high diffusion and sedimentation constants. According to size exclusion chromatography, dynamic light scattering, low angle X-ray scattering and electron microscopy, the diameter of the hyper-cross-linked species is estimated as about 12 nm in the dry state and about 17 nm in solution. In tetrahydrofuran, they associate reversibly, probably forming clusters consisting of 13 regularly packed particles. Because of the partial association, molecular weight measurements (using elastic light scattering and ultracentrifugation techniques) produce values slightly exceeding the 350 000−370 000 expected for the isolated particle.

In this paper is given an analysis of the results of the investigation of the polydispersity of polycondensation products, with linear polyarylates as an example. It has been shown that with an increase of the extent of reaction in the process of high-temperature polycondensation, the role of the interchange reactions grows, leading to the permutation of the units of macromolecules. As a result of such permutation of the units the polydispersity of the samples obtained by the high-temperature polycondensation decreases. For the products of the interphase polycondensation the coefficient of the polydispersity remains near two, regardless of the extent of reaction. The investigation of this work has shown that the MWD of the branched polyarylates resulting from the high-temperature polycondensation is greatly influenced by the reaction of polycondensation equilibrium. In spite of the high degree of branching the polydispersity coefficient remains the same as for the linear polyarylates. It has been shown that the Zimm-Stockmayer theory for the polyarylates in question gives more actual values of branching than the Zimm Kilb theory. The found empirical dependence between the parameters of the Mark-Houwink equation for linear and branched polyarylates K= 0.268 (6.03 10-5)ais similar to that found earlier for the polyamides and polyesters.