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This paper discusses a method for the synthesis of ionic liquids which are mixtures of oligomeric silsesquioxanes (OSS) of polyhedral structure and their analogs with open chains containing aprotic...

The article analyzes peculiar features of communication between users of specialized online forums devoted to motherhood. The point is considered within the framework of two approaches - linguistic (implying the analysis of the language specificity of virtual communication on the example of the mentioned Internet resources) and sociocultural (implying the analysis of the social and cultural factors of mother’s Internet forums’ emergence, predominant difference between “real” and “virtual” motherhood and the role of mentioned Internet resources in the formation of special feminine virtual subculture that has a significant impact on the perception of the modern concept of “motherhood” both in the Internet and beyond.

This paper proposes a method of obtaining the first representative of a polymeric proton-conducting medium with protic ionic groups in the main chain of a polymer by the mutual neutralization of linear telechelic oligomers with end groups of the basic and acidic nature. Oligoethylene oxide containing 1-(3-aminopropyl) imidazole fragments with two types of basic centers (aliphatic secondary amine groups and imidazole fragments) at the ends of the chain was used as the oligomer with basic properties. Sulfonic acid-terminated oligoethylene oxide was used as the acid oligomer. Protonation of aliphatic secondary amino groups in the composition of the oligomer of the basic type with the formation of an ion-elongated polymer chain is more probable at the equimolar ratio of the starting compounds according to the analysis of ΔKa values. It is shown that the synthesized polymer contains two types of crystalline formations with melting points of 37.6 °C and 46.2 °C and turns into a liquid state, when heated to higher temperature values. The proton conductivity of the polymer under anhydrous conditions is close to the conductivity of the initial sulfonic acid-terminated oligomer in the temperature inter val of 40-100 °C and reaches 2.3 · 10–4 S/cm at 100 °C, despite a much lower content of proton charge carriers.

Transformation of society inevitably leads to transformation of culture. The relevance of studying the reproductive cultural transformations of modern Russian society is increasing due to the obvious presence of gender crisis at the macrosocial and microsocial levels. Gender stereotyping in procreation is increasingly in confl ict with the variety of masculine and feminine reproductive scenarios, the demarcation of norms and pathologies of reproductive behavior. The gender approach in studying of reproductive behavior in modern Russian men and women in this article is aimed to typologize and analyze masculine and feminine reproductive scenarios – from the most conformal (pronatalistic) to oppositional (antinatalistic). The rejection of the totally naturalistic approach to the interpretation of motherhood and fatherhood in favor of analyzing the sociocultural components of the currently relevant feminine and masculine reproductive strategies is much more responsive to the social needs and the demands of modern humanitarian science.

The structure and rheological behavior of a reactive oligomeric ionic liquid (OIL) have been studied. The OIL has a linear structure and contains ionic fragments of two types at both ends of oligo(ethylene oxide) chain. The ionic fragments are represented by secondary amino groups and nitrogen-containing heterocycles protonated with ethane sulfonic acid. The results obtained using rotational rheometry in different dynamic regimes indicate that, in the linear region of deformation at temperatures T G '). The boundary, which is located at nearly 30°C, is characterized by equality between G ' and G '' in a wide range of strain amplitudes. The structural transformations induced by thermal and mechanical energies have been explained using a hypothesis of the existence of micellar structures and a “normal micelle–reverse micelle” transition in the OIL, as well as changes in micelle shapes. The analysis of the temperature dependences for the viscoelastic characteristics and scattered light intensity, as well as the data of DSC and optical microscopy, has led to the hypothesis that at, T = 21–28°C, the OIL may occur in an ordered state similar to the liquid-crystalline one.

A method for the synthesis of reactive oligomeric silsesquioxanes, combining fragments of azo dye 4-(phenylazo)phenol and fluorescent dye Rhodamine B in various proportions in an organic shell was developed. These compounds were obtained by the reaction between the oligosilsesquioxane nanoparticles consisting of a mixture of linear, branched, ladder and polyhedral structures with epoxy groups in an organic frame (OSS–Ep) and the dyes. The structure of the synthesized substances was characterized by the methods of IR and 1H NMR spectroscopy. The UV-Vis spectra of OSS–Pp–Rh in DMF solution contain absorption bands characteristic of both acidic (560 and 350 nm) and lactone (in the range of 318–326 nm) forms of Rhodamine B. The absorption band of 4-(phenylazo) phenol fragments corresponding to π−π* transition is observed at 348 nm and overlaps the absorption band of Rhodamine B at 350 nm.The intensity of the absorption bands of fragments of various dyes depends on their content in organic frame of the silsesquioxane core. The intensity of the absorption bands at 348 nm and at 560 nm increases with an increase in the content of 4-(phenylazo)phenol and Rhodamine B correspondingly.It should be noted that when using DMF as a solvent the absorption band corresponding to acidic form of Rhodamine B at 560 nm in the UV-Vis spectra of the compounds obtained is more intense than similar band in the spectrum of the original Rhodamine B. Therefore, the attachment of Rhodamine B to the silsesquioxane core of oligomeric silsesquioxanes mixture does not have a significant effect on the position of absorption maxima in the UV-spectrum and prevents dye’s fragments from converting to the colorless lactone form. In the fluorescence spectra of OSS–Pp–Rh obtained using DMF as a solvent a peak at λ max = 592 nm (λex= 520 nm) is observed. The position of the fluorescence peak and its intensity in the spectra at the same optical density of the medium practically do not depend on the ratio of fragments of 4-(phenylazo)phenol and Rhodamine B in organic frame of OSS–Pp–Rh. The combination of two different chromophores in organic shell of the silsesquioxane core broadens the range of absorbed light and the change of their ratio allows to adjust the absorption intensity in a certain area. The presence of hydroxyl groups makes it possible to introduce the obtained compounds into the composition of polymeric organic-inorganic nanocomposites by covalent bonding.

A method was developed for the synthesis of ion-coordinated polysilsesquioxanes (OSS-M) by reaction of amphiphilic carboxyl-containing oligosilsesquioxanes (OSS-COOH) with Co and Ni acetates. The OSS-M contain two types of crystalline phases, one of which is formed as a result of interaction of the alkyl chains while the other results from the formation of hydrogen bonds and coordination bonds. The size of the clusters formed by the metal ions, estimated from measurements of their magnetic moments, amounts to 2-3 nm. The magnetic nanoclusters formed by the Co ions in thin polymer films are anisotropic with respect to the plane of the substrate while the Ni ions are isotropic.

A method for the synthesis of amphiphilic reactive oligomeric silsesquioxanes (OSS) with fragments of Rhodamine B fluorescent dye and hydroxyl groups in organic shell (OSS-Rh) by the reaction between carboxyl groups of the dye and epoxy groups of the mixture of oligomeric silsesquioxanes (OSS-Ep) was developed. The structure of the synthesized substance was characterized by the methods of IR and 1H NMR spectroscopy. The UV-spectrum of the OSS-Rh compound in dimethylformamide (DMF) solution was characterized by absorption bands of both the colored zwitterion (562 nm and 350 nm) and the colorless lactone (318 nm) forms of Rhodamine B. The absorption band at 562 nm in the spectrum of OSS-Rh in DMF solution was more intense than the analogous band in the spectrum of the original Rhodamine B. Therefore, the attachment of Rhodamine B to the silsesquioxane core of an oligomeric silsesquioxanes mixture does not have a significant effect on the position of the absorption maxima in UV-spectrum and prevents dye’s fragments from converting to the colorless lactone form. In the fluorescence spectra of both Rhodamine B and OSS-Rh, obtained using ethyl alcohol as a solvent, a peak is observed at λmax = 570 nm (λex = 500 nm). In the fluorescence spectrum of OSS-Rh obtained in DMF, a fluorescence peak is observed at λmax = 586 nm (λex = 520 nm). Consequently, the replacement of ethanol by DMF is accompanied by a bathochromic shift of the fluorescence peak of OSS-Rh. In the fluorescence spectrum of Rhodamine B at the same conditions, the peak of fluorescence is absent because of transition of the dye to the lactone form. The compounds obtained can be used in formation of functional Langmuir-Blodgett films as well as in obtaining polymer nanocomposites by covalent bonding.

The main objectives in potato breeding are increasing yield abilities and improving resistance to numerous pathogens and pests. Among them, the late blight caused by the Phytophthora infestans oomycete is one of the most destructive potato diseases both in Russia and worldwide. Wild relatives of cultivated potato are traditionally used in breeding as the source of valuable R genes conferring resistance to pathogens. Of particular interest are Mexican wild species because Mexico is the centre of origin and diversity of P. infestans and at the same time, it is the centre of potato species diversity. Mexican wild potato species S. bulbocastanum and S. stoloniferum are an important source of the R genes conferring broad-spec trum resistance against various isolates of P. infestans (Rpi-blb1, Rpi-blb2, Rpi-sto1). Recently these genes have been transferred into cultivated potato gene pool using the cisgene approach. At the same time there is a high probability of finding geno types with the Rpi-sto1 gene (functional homologues of Rpi-blb1) among conventionally bred varieties because for about 40 years S. stoloniferum has been used in breeding as a source of the Rysto and Ry-fsto genes of the extreme resistance to the most important viral pathogen PVY. In this study 188 potato varieties bred in Russia and in near-abroad countries were screened for the presence of six gene-specific markers of the RB/Rpi-blb1 = Rpi-sto1 and Rpi-blb2 genes conferring broad-spectrum resistance against P. infestans, and for the markers linked to the Rysto and Ry-fsto genes conferring extreme resistance to PVY. In addition, a marker for detecting male sterile mitochondrial DNA type gamma derived from S. stoloniferum was used. The genotypes selected through the molecular markers were divided into four groups: (A) 13 PVY resistant varieties carrying diagnostic markers of the Rysto, Ry-fsto genes and having sterile mt-type gamma; (B) four varieties possessing mt-type gamma and not having the markers of the R genes introgressed from S. stoloniferum; (C) eight genotypes carrying five gene-specific markers for the RB/Rpi-blb1/= Rpi-sto1; (D) the rest 166 (86.9 %) varieties not possessing any of the diagnostic markers associated with the S. stoloniferum genetic material. The sequences of the Rpi-sto1- and BLB1 F/R-amplicons were identical in all the genotypes of group ‘C’ and showed respective 99 % and 100 % similarity to the corresponding fragments of the Rpi-sto1 and Rpi-blb1 genes from the GenBank database. Among the genotypes of group ‘C’ various mt-types were detected, and some of them were male fertile.

Reactive linear oligo(ethylene oxides) containing terminal secondary hydroxyl groups and secondary amino groups combined with nitrogen heterocyclic fragments are synthesized by the reaction of oligo(oxyethylene glycol) α,ω-diglycidyl ether (М = 1.0 × 103) with 1-(3-aminopropyl)imidazole, 2-aminopyridine, or 2-amino-3-methylpyridine. Protonation of the synthesized compounds by ethanesulfonic acid and p-toluenesulfonic acid at their different ratios is studied. This process makes it possible to obtain oligomeric linear protic cationic ionic liquids capable of condensation. The proton conductivity of oligomeric ionic liquids is investigated under anhydrous conditions in the temperature range of 40–120°С. The highest conductivity (1.36 × 10–3 S/cm) is attained in the case of methylpyridinium ethanesulfonate oligomeric ionic liquid at 120°С. These compounds are thermally stable to a temperature of 250–290°С. They show promise for the synthesis of polymeric analogs of block ionic liquids suitable in the production of electrochemical devices for various purposes.

Methods were developed in order to control the hydrophilic and hydrophobic properties of anionic amphiphilic protic ionic liquids with hyperbranched structures. The structurizing ability of the compounds in the condensed state depends on the ratio of hydrophilic and hydrophobic components. Self-organization with the formation of nanosized assemblies in aqueous solution and at the interface also depends on change in the pH and ionic strength of the medium. The obtained data form the basis for creation of materials with promising ionic liquid properties for various electrochemical devices and transport media.

Metabolite profile adjustments under impact of ethylene synthesis inhibitors were studied in Arabidopsis thaliana (L.) Heynh. seedlings during reorientation of plants relative to the gravity vector (gravistimulation). Metabolite profiles were compared with Principal Component Analysis. We have shown that significant changes in metabolite profiles developed within 60 min of gravistimulation and were most pronounced in 2 mm root tips including the root cap, apical meristem and elongation zone. Gravistimulation resulted in the increased levels of valine, leucine, serine, γ-aminobutyric acid, nicotinic acid, and decreased levels of several monosaccharides, malate and oxalate. Treatment with ethylene synthesis inhibitor, aminoethoxyvinylglycine (10 μM), escaped the effect of gravistimulation on root tip metabolite profile. Metabolite profile adjustments revealed in this study suggest that ethylene may be involved into the regulation of Arabidopsis metabolome during the gravitropic response.

The genetic diversity of potato varieties from the collection of Vavilov Institute of Plant Genetic Resources (VIR) was analyzed based on microsatellite analysis. These varieties have been bred in Russia and its neighboring countries since 1931. Application of 14 highly polymorphic nuclear microsatellites (SSRs) has enabled 113 varieties to be fully distinguished. Additionally, we have studied these varieties for the distribution of 8 DNA markers associated with three R-genes involved in controlling resistance to two quarantine objects: potato wart Synchytrium endobioticum and golden potato cyst nematode Globodera rostochiensis, occurring locally in some regions of the Russian Federation. All the analyzed varieties with resistance to the S. endobioticum pathotype 1 revealed the diagnostic marker Nl251400 of the Sen1 gene, while a few susceptible cultivars lost this diagnostic fragment. The tested markers of the H1 and Gro1-4 genes, which confer resistance to the G. rostochiensis pathotype Ro1 revealed different predictability. In the molecular screening of potato varieties, it is better to use several markers of these genes. The results of molecular screening using six markers of H1 and Gro1-4 genes allowed us to detect six haplotypes in the tested subset. Five haplotypes include varieties with different combinations of the markers tested; the majority (87.9%) of these varieties were highly resistant or moderately resistant to G. rostochiensis. The most numerous haplotype H1/0 included 76 varieties, which did not possess any marker of H1 and Gro1-4 genes; 96.1% of these varieties were susceptible to G. rostochiensis. Predictive associations between the haplotype content, wart and nematode resistance, pedigree, and the variety in their age are discussed.

The method of synthesizing anionic amphiphilic protic hyperbranched ionic liquids with the controlled ratio between hydrophilic ionic-liquid groups and hydrophobic alkyl urethane fragments in the oligoester nucleus shell is developed. These compounds are synthesized by the interaction of excess hyperbranched polyesterpolyol containing 32 terminal hydroxyl groups with n-octadecyl isocynate followed by the acylation of hydroxyl groups by phthalic anhydride or 2-sulfobenzoic anhydride and the neutralization of the formed carboxyl or sulfonic groups by N-methylimidazole or 1,2,4-1H-triazole. With a rise in the content of alkyl urethane fragments, the synthesized compounds form the crystalline phase. Structuring of the system leads to different effects of the degree of ionicity of ionic-liquid groups on proton conductivity, which is within 10–7–10–4 S/cm at 100–120°C under anhydrous conditions. The thermal stability of the hyperbranched ionic liquids is determined by the nature of ionic-liquid groups and the amount of the introduced alkyl urethane fragments; it is in the range of 170–270°C.

The series of amphiphilic anionic protic hyperbranched oligomeric and polymeric ionic liquids (HBP-OILs) with different terminal groups and an adjustable hydrophilic-hydrophobic balance which are sensitive to pH and ionic strength changes was obtained by neutralizing the carboxylic and sulfonic terminal acid groups of aliphatic hyperbranched core with N-methylimidazole (Im) and 1,2,4-1H-triazole (Tr). The introduction of long hydrophobic aliphatic tails to starting hydrophobic hyperbranched core influences more significantly on the size of micellar assemblies than the introduction of ionic groups does. The assembly of these compounds into core-corona micelles in aqueous media in a wide range of pH and ionic conditions was established. Regulation of HBP-OILs amphiphilicity can be realized by varying the extent of ionization of terminal groups by changing pH or ionic strength. The synthesis of the thermally responsive protic anionic hyperbranched poly(ionic liquid)s (HBP-PILs) was based on partial (50%) and full neutralization of carboxyl groups of aliphatic polyester core by monoamine-terminated poly(N-isopropylacrylamide)s (PNIPAM). Its linear oligoester analog was synthesized in a similar way. These compounds possess low critical solution temperature (LCST) behavior with a narrow LCST window and amorphous state in condensed matter. We found that HBP-PILs form smaller in comparison with linear analogues spherical micelles and their aggregates of different morphologies depending on the content of PNIPAM. When temperature is higher than LCST the formation of spherical micelles, network-like aggregates and large vesicles is observed. In opposite to initial cores prone to form spherical domains the thermally responsive compounds are able to self-assemble into elongated unimolecular nanodomain. The complex self-assembling behavior and diverse morphology of resultant supramolecular assamblies of HBP-OILs and HBP-PILs might lead to unique ionic transport properties as a key point for creation of nanomaterials with tunable ion transport characteristics.

A method of obtaining new organic-inorganic nanostructured proton-exchange membranes operating via the anhydrous proton-conduction mechanism is proposed. An oligo(ethylene oxide) component serves as a proton-conducting phase in these membranes, and the sulfo derivatives of octahedral oligosilsesquioxanes of the acidic and acid-base types are used as proton-donor dopants. These compounds are synthesized via the reaction of octaaminopropyl oligosilsesquioxane with the cyclic anhydride of 2-sulfobenzoic acid at various ratios and contain sulfo groups solely or sulfo and amine groups in the organic frame. The combination of these compounds taken at concentrations of 20 and 50 wt % with α,ω-di(triethoxysilyl) oligo(oxyethylene urethane urea) and phenyltriethoxysilane via the sol-gel method gives rise to hybrid organic-inorganic proton-exchange membranes. The synthesized dopants are distributed in the oligoether component, but the nature of dopant distribution depends on their structure and concentration and has a significant impact on the structure of the resulting amorphous membranes (according to DSC, SAXS, and AFM data). The synthesized membranes are thermally stable up to 219°C. Their conductivity is provided by the segmental mobility of oligooxyethylene fragments (the Grotthuss mechanism) and, regardless of the dopant structure, is primarily determined by the number of charge carriers and the membrane structure. The temperature dependence of the conductivity is described by the Vogel-Fulcher-Tammann equation. The maximum values of the ionic conductivity are attained at 120°C under anhydrous conditions and dopant concentration of 50%: 1.03 × 10−4 for ampholytic oligosilsesquioxane and 7.43 ×10−5 S/cm for fully sulfonated oligosilsesquioxane as a dopant.

Decontamination of liquid radioactive waste (LW) from transuranium elements (TUEs) and uranium by complexation with phosphorus-containing and guanidine phosphate oligoethers and by ultrafiltration was studied. The rejection coefficient of TUEs and U on these oligomers reaches 99.0–99.6% of the initial concentration.

Approaches to the production of polymeric organic–inorganic hybrid proton-exchange membranes for fuel cells by the sol–gel method are summarized, and a classification is proposed for them. Features of the mechanism of conduction in the proton-conducting membranes are considered. Characteristics of the hybrid membranes and of fuel cells using them are presented. The main directions of research in this field are discussed.

The interaction of oligomeric silsesquioxanes, whose organic moieties contain tertiary amino groups and primary and secondary hydroxyl groups, with monoisocyanates and phthalic and acetic anhydrides is employed to synthesize a number of their N-alkyl(aryl)urethane-, carboxyl- and acetyl-terminated derivatives with different degrees of substitution and combinations of the substituents. The obtained derivatives are studied by functional analysis, IR spectroscopy, GPC, DSC, TGA, and wide-angle X-ray scattering. The chemical nature of the incorporated functional groups is found to markedly influence the structure and properties of the synthesized compounds. Depending on the type of substituents and their combination, either the complete amorphization or ordering of the structure of the oligosilsesquioxanes is observed with corresponding changes in their properties.

Polyhedral oligomeric silsesquioxanes (POSS) with an empirical formula [RSiO1.5]n (where n = 6, 8,…14, and R is a reactive organic group) represent a new type of nanomodifiers for polyurethanes (PUs) to produce organic–inorganic hybrids (OIHs), which are promising candidates for modern applications spreading from biomedical to airspace technologies. In this paper we report on the synthesis and structural organization of two different series of PU–POSS copolymers (branched and cross-linked) based on a mixture of variable size oligomeric silsesquioxanes (POSS-M) of a general formula [(HOCH2CH(OH)CH2)2N(CH2)3SiO1,5]n. Chemical structure of the synthesized POSS-M containing PUs has been confirmed by gel permeation chromatography and IR spectroscopic studies. Complex several-level hierarchy of their physical structural organization could be recognized from small angle X-ray scattering (SAXS) and atomic force microscopic (AFM) studies. SAXS experiments revealed that processes of microphase segregation and formation of nano-sized domains enriched with the inorganic phase (POSS fragments) take place during synthesis of the OIH systems. These nano-heterogeneity regions contain up to 66 vol.% of SiO1.5 and form a paracrystalline lattice with hexagonal symmetry and characteristic interplanar periodicity of around 15 nm. The average size of inorganic phase nano-inclusions can be estimated as 2–3 nm, which corresponds to several POSS moieties in size. Cross-linked POSS-M containing PUs, as topologically more complex systems, is characterized with a diffusion-limited microphase segregation features. In the latter case the regions of nano-heterogeneity are smaller in size, have smaller content of the inorganic phase (ca. 54 vol.%), and form a less perfect paracrystalline order with the periodicity of 9.7 nm. Generally, we demonstrate that replacement of regular POSS moieties with the mixed POSS-M ones can lead to nanocomposite systems with an ordered supramolecular structural organization and simultaneous reduction of their production cost due to relative simplicity of their synthesis.

This paper reports on the results of investigations into the specific features of the deposition of hybrid organic-inorganic borosilicate films prepared by the sol-gel method for the use in the planar technology of microelectronics. In order to modify the properties of the borosilicate films, a number of water-soluble hydroxyl-containing oligomers (with different molecular topologies and different molecular weights from 300 to 5100 g/mol) are introduced into the sol-gel system. The effect of these polyols on the sol viscosity, the thickness, and the surface morphology of the synthesized films is revealed by viscometry, ellipsometry, optical microscopy, atomic-force microscopy, and thermal analysis. These films are designed for the use as sources for boron diffusion into silicon in order to fabricate heavily doped diffusion layers with a dopant concentration of (5–7) × 1020 cm−3. The depth of occurrence of diffusion layers is approximately equal to 4 μm.

This paper reports on the results of rheological investigations into the kinetics of gelation of the sol-gel systems based on a water-alcohol solution of tetraethoxysilane (TEOS) modified by a number of metal salts and organic polyhydroxyl compounds, such as glycerol, poly(ethylene glycol) (PEG-300), and hyperbranched aliphatic complex polyol polyethers (HBP-49, HBP-64). It is demonstrated that, at a dispersed phase concentration of approximately 10 wt %, water-ethanol sol-gel systems containing 2–4 g/l of high-molecular additives possess a shear strength and are characterized by anomalous properties in their flow. The gelation time of sols in the presence of organic additives is affected by the ratio between the numbers of OH− hydrophilic and CH3 hydrophobic groups in the polymer molecule, the concentration of the introduced additive, and the electrolyte multivalence. The presence of metal salts enhances the structuring effect of polymers.

The feasibility of activated carbon (AC) bioregeneration after adsorption of biologically resistant surface-active substances (SAS) by a community of strains of SAS-degrading bacteria of the genus Pseudomonas are analyzed. It was shown that the degree of AC equilibrium saturated with nonionic SAS under static conditions was 23–35%. The contribution of bacterial destruction of SAS to the restored capacity was 20–23% and, for all practical purposes, did not depend on the AC porosity. The efficiency of regeneration of the microporous AC after adsorption by it of the nonionic and anionic SAS under dynamic conditions was 22 and 95% of the respective capacities of fresh samples. The extent of regeneration of the mesoporous AC after dynamic sorption of nonionic SAS was 85%. Results indicate that regeneration is based on desorptive and migrational movements of the adsorbate toward the biocenosis of SAS-degrading bacteria located on the external surface of the AC grain. The adsorptive properties of the AC–SAS system and the sorbents’ porous structure determine the probability of desorption of molecules and the rate of their diffusion into the peripheral zone of the grain. The AC regeneration efficiency depends on the nature of the adsorbate distribution in its porous structure.

We report on the synthesis of a series of second-generation hyperbranched polyesters with a variable composition of alkyl-terminated groups. We observed that the chemical modification of the hyperbranched cores by substituting a controlled fraction of the terminal hydroxyl groups with hydrophobic alkyl chains is an effective method for a controlling amphiphilic balance of hyperbranched cores with a degree of branching of 50%. Even for imperfect cores, the chemical reaction of hydroxyl groups alkyl tails was very efficient. In fact, the number of attached alkyl tails was fairly close to the theoretical value based on the assumption that all targeted hydroxyl groups were available for the reaction despite their different interior/exterior location. Detailed microstructural analysis of the structure revealed that organized monolayers could be formed at the air-water interface if the number of alkyl tails was higher than two per core. Similar to regular dendrimers, the alkyl tails of hyperbranched molecules at high surface pressure form intramonolayer ordering of the quasi-hexagonal type. However, higher defectness and irregularities of the hyperbranched cores are responsible for poor intralayer ordering of alkyl tails in comparison with regular dendrimers. At high surface pressure, the alkyl tails became arranged in an up-right orientation. The highly water-swollen state of the hyperbranched cores of prolate shape and the partially submerged and standing-off alkyl tails is a characteristic of hyperbranched molecules with fewer alkyl chains in condensed monolayer state at the air-water interface. The core structure is transformed into the oblate, flattened state with preservation of standing-off orientation of the alkyl tails for hyperbranched molecules with crowded outer shells.

Organic–inorganic composites are synthesized by introducing a number of low- and high-molecular water-soluble polyhydroxyl compounds (with different molecular weights and different molecular structures) into sols based on tetraethoxysilane. The coatings on nickel substrates are prepared by adding chromium dioxide as a finely disperse filler to the soles. The rheological properties of the sol–gel systems synthesized are investigated, and the surface condition and the microstructure of the coatings formed are examined. The xerogels and the coatings are studied by differential thermal and X-ray powder diffraction analyses.

The approach for improving bending strength of temperature-resistant flexible ceramic electric insulating coatings prepared by sol-gel processing is considered. Starting suspensions, based on both tetraethoxysilane (TEOS)-derived modified sols and highly dispersed fillers such as Cr2O3, are used to deposit the coatings on metals and alloys. Some polymers and organic substances are tested as additives for improving flexibility of the ceramic coatings. The results of study of both bending strength and electrical strength of flexible hybrid organic-inorganic insulation formed on a nichrome wire are discussed. The data obtained on the chemical and phase structure of the coatings, which have been heat treated at temperatures from 95 to 1100°C, using DSC as well as X-ray scattering techniques are presented.

The thermal transitions, microphase structure, local segmental and conductivity relaxation of the novel polyurethanes (PUs) based on the poly(tetramethylene glycol) as soft segments (SSs) and 4,4′-diphenylmethane diisocyanate-1,4-butane diol sequences of various length as hard segments (HSs) containing ionic groups in SSs are studied by calorimetry, X-ray scattering and dielectric relaxation spectroscopy.

The thermal transitions, microphase structure, local segmental and conductivity relaxation of the novel polyurethanes (PUs) based on the poly(tetramethylene glycol) as soft segments (SSs) and 4,4′-diphenylmethane diisocyanate-1,4-butane diol sequences of various length as hard segments (HSs) containing acid or ionic groups in SSs are studied by calorimetry, X-ray scattering and dielectric relaxation spectroscopy. The techniques used include differential scanning calorimetry, 173–473 K, wide-angle X-ray scattering, (WAXS) small-angle X-ray scattering (SAXS), broad band dielectric relaxation spectroscopy (DRS), 10−2–106 Hz, and thermally stimulated depolarization currents (TSDC) techniques, 100–300 K. The peculiarities of microphase-separated structure (MSS) of the PUs such as composition of the microphases, periodicity of non-ionic PU MSS (about 17 nm), size of ionic aggregates in the ionomer (about 7 nm) and their distribution in the SS matrix were determined. The features of α-relaxation, conductivity relaxation and dc conductivity of the proton-conducting PU with acid groups and ion-conducting PU with ionic ones are found and discussed in connection with MSS of the PUs. The level of protonic dc conductivity increases with temperature up to 10−5 S/m (323 K), whereas the ionic PU exhibits by about two decades lower conductivities, evidently due to ionic aggregation. Accordingly for the latter, apparent activation energy of the conductivity relaxation is considerably more than for the former.

Novel polyurethane (PU) ionomers based on poly(teramethylene oxide) (PTMO) or poly(ethylene oxide) (PEO), with nonionic hard segments of varying length and flexible segments containing sodium ions (Na + ), have been prepared and their structure-property relationships have been investigated. The structure and the morphology were studied by means of differential scanning calorimetry (DSC), infrared (IR) spectroscopy and small-angle X-ray scattering (SAXS). Ionic conductivity was studied by means of broadband dielectric relaxation spectroscopy (DRS, 10 -2 -10 9 Hz). PTMO-based ionomers are characterized by the coexistence of segment microphase separation and ionic group segregation morphologies. In the PEO-based ionomers, crystallization is observed at low hard segment content, with a tendency for crystallization to decrease upon hard segment extension. Values of ionic conductivity are in the range 10 -7 Sm -1 to 10 -4 Sm -1 at 323 K for PU ionomers based on PTMO and PEO, respectively.

Thermal transitions, morphology and electric conductivity of polyurethanes that contain acid (COOH) groups bound to their polyether (poly(tetramethylene oxide)) chains and hard urethane segments of various length have been studied by means of calorimetry, wide- and small-angle X-ray scattering and a.c. conductivity in wide range of frequencies (0.1 Hz–1 MHz) and temperature (−100 to 100°C). It was shown that the polyurethanes are basically microphase-separated systems whose polyether-rich matrix contain from 20 to 25% of the hard urethane fragments. The protonic conductivity of the materials decreases with decreasing the polyether phase in the system.

Hyperbranched poly(ester urethanes) containing end isocyanate groups have been synthesized via the reaction of hyperbranched aliphatic polyesterpolydiols of three generations with tolylene diisocyanate. The interaction of these compounds with N,N-dimethylaminoethanol yields their functional derivatives. The polymers are characterized by functional analysis, 1H NMR and IR spectroscopy, and DSC. It has been demonstrated that the incorporation of urethane moieties leads to development of the microheterogeneous structure of hyperbranched polymers.

This study probes the behavior of two series of organic-functionalized core-shell silsesquioxane (POSS-M)p-(x/y) derivatives with various hydrophobic-hydrophilic terminal group compositions in the bulk state and within mono- and multilayered films at the air-water interface and on solid surface. POSS-M refers to mixed silsesquioxane cores, in contrast to the geometrically specific POSS compounds. It is composed of polyhedra, incompletely condensed polyhedra, ladder-type structures, linear structures, and all the possible combinations thereof and attracts great interest because of its facile preparation, low polydispersity, high yield, and low cost. The two series of (POSS-M)p-(x/y) molecules are different in hydrophobic-hydrophilic balance of their terminal groups, with x and y respectively referring to the molar percent of -OCONH-C(18)H(37) tails and -OH for p = 1 and the percent of -OCONH-C(18)H(37) tails and -OCO-C(6)H(4)COOH terminal groups for p = 2. In the bulk state, the presence of aromatic rings in (POSS-M)2-(x/y) series resulted in a lower symmetry crystal structure than the (POSS-M)1-(x/y) series. Moreover, the (POSS-M)p-(x/y) molecules that contain a sufficient amount of -OCONH-C(18)H(37) tails exhibit double endothermic transition, which attributed to the melting of alkyl chains followed by the melting of the unit cells of (POSS-M) cores. The surface morphologies for the various hydrophobic-hydrophilic combinations at surface pressure p = 0.5 mN/m are similar to that observed for the classical amphiphilic star polymers. However, at higher surface pressure (por = 5 mN/m), the POSS-M compounds with lower content of hydrophilic groups form a uniform monolayer.