Amphiphilic block copolymers of N-pyrrolidone and styrene were prepared by chain transfer to organogermanium compounds bis(pentafluorophenyl)germane and tris(pentafluorophenyl)germane. The relative chain-transfer constants were determined. The surface properties of the isolated block copolymers with various numbers of units in the hydrophilic block were studied. The polar and dispersive components of the surface tension of films of the amphiphilic block copolymers were calculated by the Zisman method.

Polymers of various structures, namely, the model PS with pentafluorophenyl groups, the linear-dendrite perfluorinated polyphenylenegermane-polystyrene, and diblock copolymer polystyrene-Ge(C 6 F 5 ) 2 -polystyrene, have been prepared by radical polymerization and activated copolycondensation. The polymers have been studied in dilute solutions by GPC, static and dynamic light scattering, and viscometry. The addition of a bis(pentafluorophenyl group) to the ends of a PS chain facilitates the development of supramolecular structures in solutions of hybrid systems. If the fluorinated group is incorporated at the center of the polymer chain, no associative phenomena are observed, because of its screening by the molecular coil.

Fractions of the product resulting from the polymerization of methyl methacrylate in the presence of hyperbranched perfluorinated poly(phenylene germane) have been studied by dynamic and static light scattering and capillary viscometry in methyl ethyl ketone solutions. The hybrid product is obtained via the reaction of the chain transfer of methyl methacrylate propagating radicals to pentafluorophenyl groups. Eight fractions have been isolated by fractional precipitation, including fractions of the linear-dendrite block copolymer. Light scattering studies have shown that hybrid macromolecules containing 15–20 wt % hyper-branched fragments form micelles in solutions.

In the present work, temperature dependence of heat capacity of the block copolymer based on hyperbranched perfluorinated poly(phenylenegermane) and atactic polystyrene has been measured first in the range from 6 to 350K and between 320 and 534K, respectively, by precision adiabatic vacuum and dynamic calorimetry. In the above temperature ranges, the devitrification of constituent blocks was detected and its thermodynamic characteristics have been determined and analyzed. The experimental data were used to calculate standard thermodynamic functions, namely the heat capacity Cp°(T), enthalpy H°(T)−H°(0), entropy S°(T)−S°(0) and Gibbs function G°(T)−H°(0), for the range from T→0 to 518K. The standard thermodynamic properties of the said substance were compared with corresponding data for the initial homopolymers as well as for the block copolymer on basis of hyperbranched perfluorinated poly(phenylenegermane) and atactic poly(methylmeth)acrylate studied earlier.

A method for determining the molecular weight of hyperbranched polymers is developed, based on the measurement of the area of the monolayer at the water/air interface.

The dilute solutions of the hyperbranched perfluorinated polyphenylenegermane-PMAA block copolymer have been studied by dynamic and static light scattering and viscometry. It has been demonstrated that macromolecules of the block copolymer aggregate in all the solvents under study (methyl ethyl ketone, dioxane, and ethyl acetate) and form elongated micelles.

Surface pressure isotherms at the water-air interface were measured for monomolecular films of poly(4-vinylpyridine) (M = (1-27) x 10(4)), the hyperbranched perfluorinated poly(phenylenegermane) (M = 1.4 x 10(4)), and their mixtures, as well as of the product of the free-radical polymerization of 4-vinylpyridine obtained in the presence of the perfluorinated poly (phenylenegermane). It was shown that a decrease in the pH of a substrate has no effect on the characteristics of surface pressure isotherms of the perfluorinated poly(phenylenegermane) but brings about degradation of the adsorption layer of poly (4-vinylpyridine). In the case of the polymer mixture and especially of the polymerization product, a rise in the acidity of the substrate promotes an increase in the stability of monomolecular films. It was inferred that the surfactant properties of the mixture are associated with the presence of amphiphilic associates that appear owing to hydrophobic interactions between unionized units; in the case of the polymerization product, the surfactant behavior is attributed to the formation of an amphiphilic linear-dendritic block copolymer via chain transfer to the hyperbranched polymer.

The wettability and surface topography of films prepared from mechanical blends of PMMA and the dendritic hyperbranched perfluorinated poly(phenylene germane), as well as of the product of methyl methacrylate polymerization carried out in the presence of the latter polymer, were studied. Even at a small amount of the hydrophobic perfluorinated poly(phenylene germane), films prepared from solutions of mechanical blends in THF were not wet by water (theta = 120 degrees), while films prepared from chloroform solutions were wet by water at a greater amount of this polymer (theta < 90 degrees). The former effect is due to the surface segregation, while the latter effect is related to the formation of disklike leaf-shaped PMMA particles. Methylene iodide wet the films of mechanical blends and of the product of MMA polymerization obtained in the presence of poly(phenylenegermane). The latter films were also wet by water. The surface topography of films prepared from the polymerization product was significantly affected by the nature of the solvent.

The free-radical polymerization of methyl methacrylate and methyl acrylate, when carried out to a conversion of 15-18% in the presence of 15-20 wt % of the hyperbranched perfluorinated poly(phenylenegermane) of the empirical formula [(C6F5)(2)C6F4Ge](n), leads to the binding of 30-40% of the latter polymer via the chain-transfer reaction. The feasibility of this reaction was established with the use of the model compound tetrakis(pentafluorophenyl)germane for the polymerization of methyl methacrylate (C-S = 0.1) and methyl acrylate (C-S = 0.2). Products arising from the polymerization of these monomers in the presence of the hyperbranched polymer are characterized by the bimodal molecular-mass distribution. A low-molecular-mass fraction with M-w = (2-3) x 10(4) was assigned to the one-arm block copolymer, while the high-molecular-mass fraction having M-w = (0.8-1.0) x 10(6) was attributed to multiarm structures resulting from transformations specific to the system under study. When the polymerization of methyl methacrylate in the presence of 20 wt % of the perfluorinated poly(phenylenegermane) was conducted to maximum conversions, the product containing a block copolymer was isolated. For this copolymer, the temperature dependence of heat capacity was studied by precision adiabatic vacuum calorimetry in the 6-350 K range and dynamic scanning calorimetry in the range from 320 to 450 K, thermodynamic characteristics of devitrification of constituent blocks were determined and analyzed, and standard thermodynamic functions were calculated.

The formation of hyperbranched perfluorinated poly(phenylenegermane) macromolecules was studied. Velocity sedimentation measurements with five samples of perfluorinated poly (phenylenegermane), which was prepared at different concentrations of an activator-triethylamine-showed that the maximum equivalent radii and molecular masses of macromolecules are R = 1.5-1.6 mm and M = (1.7-2.2) x 10(4). These values are close to those obtained by modeling performed for a sphere corresponding to the third generation (R = 1.6-1.7 nm, M = 2.2 x 10(4)). Using, the Langmuir film balance, it was found that the effective radius of a perfluorinated poly(phenylenegermane) macromolecule is equal to 1.75 nm.

Homo- and copolymers of 1-vinyl-1,2,4-triazole with acrylamide and quarternary salt of polyvinyltriazole were prepared. The flocculation power of these (co)polymers was studied using model kaolin suspensions.