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Poly(urethane-imide) copolymers (PUICs) containing reactive carboxyl groups in hard imide segment were synthesized from poly(propylene glycol) with isocyanate end groups, 1,3-bis(3′,4′-dicarboxyphenoxy)benzene dianhydride, aromatic diamines 4,4′-bis(4″-aminophenoxy)diphenyl sulfone or 4,4′-bis-(4″-aminophenoxy)biphenyl, and 3,5-diaminobenzoic acid. The PUICs were covalently cross-linked using reactions of carboxyl groups with aromatic diisocyanates and 1,2,5,6-diepoxycyclooctane. The polymers obtained were studied by thermogravimetric analysis, differential scanning calorimetry, and dynamic mechanical analysis. It was shown that the structure of the cross-linking agents influences the properties of cross-linked PUICs. Changes in the mechanical loss factor (tg δ) were analyzed vs. chemical structure of the PUICs. The maximum tg δ values of the copolymers studied are in the range of 0.3–0.4, which suggests good damping capacity of these systems.

The effect of synthesis conditions for macrodiisocyanate (temperature, reaction duration, ratio of components) based on poly(diethylene glycol adipate) (Mn = 2.5 × 103) and 2,4-toluene diisocyanate on the composition of the reaction products has been studied. The number of mono- and diurethane units was estimated using proton magnetic resonance spectra. It was found that carrying out the synthesis at 80°C using an eight-fold excess of 2,4-toluene diisocyanate results in the production of a macrodiisocyanate with a diurethane unit content of less than 1 mol %. Based on the isolated macrodiisocyanate, a fusible polyurethanimide, superior in elasticity to the unmodified analogue, was prepared.

The series of compositions containing thermodynamically incompatible flexible blocks of aliphatic polyesters and rigid blocks of aromatic bis (urethane) imides in the volume of polymers was obtained on the basis of multiblock (segmented) poly (urethane-imides) and related aromatic polyimides. The series includes segmented poly (urethane-imides) with different relative content of flexible and rigid blocks, non-segregating mixtures of poly (urethane-imides) and thermoplastic partially crystalline polyimide, statistical copolymers of poly (urethane-imide) with imide, and non-segregating mixtures of statistical copolymers with thermoplastic polyimide. The derived polymer systems were studied using thermogravimetric analysis, differential scanning calorimetry, and dynamic mechanical analysis. The deformation and strength properties of film samples are determined. It is shown that the properties of the studied polymers change as their content of imides blocks increases, and the transition from thermoplastic poly (urethane-imide) elastomers to thermoplastic polyimides is observed.

A review of the works performed at the Institute of Macromolecular Compounds, Russian Academy of Sciences in the field of multiblock copoly(urethane–imide)s, a relatively new subclass of thermally stable polymers, is presented. The synthesis of the representative family of copoly(urethane–imide)s different in the chemical structure and ratio of flexible polyester/polyether and rigid urethane–imide blocks is performed. Mixed compounds composed of synthesized copoly(urethane–imide)s and thermoplastic polyimides are obtained. The effect of the chemical structure of the flexible and rigid blocks and their ratio on the glass and melting transitions of the studied polymer systems is investigated. Polymer systems that form stable melts and are suitable for processing to thick-wall products, thermoplastic elastomers, are proposed.

Based on poly[di(ethylene glycol) adipate] (Mn = 2500) terminated by 2,4-toluene diiso-cyanate (TDI), bis(3´,4-dicarboxyphenoxy)benzene (dianhydride R), and 1,4-bis(4´-amino-phenoxy)biphenyl (diamine ODFO) a number of co-poly(urethane-imide) samples with the general formula (R-TDI-2500-TDI-R)(ODFO)n (n = 1–3, 5), differing in the content of aromatic blocks (from 37 to 65 wt.%) were obtained. The synthesized samples were characterized by the TGA, DSC, and DMA methods and were used to prepare mixed compositions with the known R-ODFO polyimide in two versions, namely, with a polyimide content of 10 and 90 wt.%. Mixed compositions were investigated by DSC. The effect of an increase in the relative content of imide units on the glass transition and melting temperatures of the crystalline phase of copolymers and mixed compositions is detected.

A blend of crystallizing polyimide and newly synthesized partially crystalline multiblock (segmented) copoly(urethane—imide), consisting of 75 wt % copoly(urethane—imide) and 25 wt % polyimide, was prepared and studied by thermal gravimetric analysis, differential scanning calorimetry, dynamic mechanical analysis, and melt rheology. Blend samples were prepared by mixing copoly(urethane—imide) and polyimide prepolymers in an N-methyl-2-pyrrolidone solution, in which the subsequent thermal or chemical imidization of the system components was performed. The properties of the initial polyimide, copoly(urethane—imide), and the blend were compared. The results of studies by differential scanning calorimetry and dynamic mechanical analysis demonstrate the presence of a crystalline soft polyester phase in the copoly(urethane—imide) structure and of the crystalline hard imide phase in the blend structure, which suggests the crystallization suppression in samples of the blend. The dynamic viscosity of the melt of chemically imidized copoly(urethane—imide) and blend samples is lower than that of their thermally imidized analogs. Dynamic mechanical analysis shows that the initial copoly(urethane—imide) behaves as a thermoelastoplastic. The blends consisting of copoly(urethane—imide) and thermoplastic polyimide are similar in properties to polyimide thermoplastics for structural purposes.

Poly (diethylene glycol) adipate diol, tolylene-2,4-diisocyanate, 1,3-bis (3',4-dicarboxylphenoxy) benzene and 1,4-bis (4'-aminophenoxy) biphenyl were used as monomers to form statistical copoly (urethane-imide) s with variable content of imide blocks (from 37 to 65% (wt)). The copolymers imide blocks on the Tg and Tm values relative content increasing effect was traced, which is associated with the phase separation of hard imide and flexible polyester blocks in the systems studied.

Organic-inorganic composites filled with nanoscale graphene and tungsten disulfide particles using thermoelastoplastic multiblock co-poly(urethane-imide)s as polymer matrices were obtained. The matrix polymers were the products of the polycondensation of 1,3-bis-(3′,4-dicarboxyphenoxy)benzene dianhydride, 1,4-bis(aminophenoxy)diphenyl sulfone, and two aliphatic polyesters terminated by 2,4-toluene diisocyanate, namely, polypropylene glycol (Mn = 2300) and poly(ethylene adipate) (Mn = 2700). The weight fraction of aromatic segments in samples of co-poly(urethane-imide)s differed by a factor of two. Obtained composites were investigated by TGA, DSC, and DMA methods.

New segmented polyurethaneimides containing poly(ethylene glycol adipate) soft segments and bis(urethaneimide) hard segments are synthesized. Copolymers are obtained on the basis of poly(ethylene glycol adipate) (Mn = 2.5 × 103) terminated with 2,4-toluene diisocyanate, two aromatic dianhydrides, and six aromatic diamines. The structure of the synthesized polymers is studied by IR and NMR spectroscopy. The thermal properties of the copolymers are characterized by TGA and DSC. Effects of hard segment length and substituent position in the diamine fragment on the thermal and mechanical properties of the polyurethaneimides are investigated.

We synthesized 2,6-poly(phenylquinoline)s, the elementary polymer unit of which contained alkyl carbazole or alkyl indolo[3,2-b]carbazole moieties with C12 and C18 alkyl side chains at nitrogen atoms and the oxygen or phenylamine bridge group between the quinoline cycles. The synthesized polymers form heat-resistant coatings, for which the temperature for 5% weight loss is higher than 450°С. It is demonstrated that introduction of 10 wt % of 2,1,3-benzothiadiazole to the poly(phenylquinoline)s leads to an increase in the photosensitivity of the composite as compared with the original polymers. Structural-morphological studies of the synthesized poly(phenylquinoline)s and their composites were carried out.

One- and two-step syntheses of composite coatings with an A–OOO polyimide matrix filled with 40-nm tungsten disulfide nanoparticles produced using gas-phase synthesis, which are intended for operation under dry friction conditions, are described. Results of studying the tribological behavior of these coatings are presented.

The paper experimentally studies the effect of meta and para- substitution of the amino groups in the diamine used in the synthesis of multiblock copolymers. The way for synthesis of new multiblock copolymers with the possibility of replacing the diamine in the polymer structure was shown. Thermal and mechanical properties of synthesized copolymers had been characterized by means of differential scanning calorimetry, thermogravimetric analysis, dynamic mechanical thermal analysis and by nanoindentation and tensile test.

The dielectric relaxation and molecular mobility of multiblock segmented copolyurethane imides based on pyromellitic anhydride and aromatic diamines and 2.4-methylene diisocianate (forms a rigid urethane imide segment) terminated polybutylene adipate (Mn 2700) (forms a soft segment) were studied by the dielectric method. It was found several dipole relaxation processes, local γ and β (in the glassy state) and cooperative α1 and α related to the soft and rigid phase, respectively (in the rubbery state). Beside this, Maxwell Wagner Sillars (MWS) process associated with interfacial polarization was observed. The presence of α, α1, and MWS processes is a reliable indication of the microphase separation in the studied systems.

A synthesis is described and tribological characteristics are presented for composite coatings 40 μm thick with a PM–DADPE polyimide matrix and a filler of tungsten disulfide nanoparticles with size of 4 nm and tungsten diselenide nanoparticles 60 × 5 nm in size obtained via gas-phase synthesis.

On the basis of pyromellitic dianhydride, p-phenylenediamine, and poly(butylene adipate) diol (M n = 1 × 103) and poly(ethylene adipate) diol (M n = 1 × 104) taken at a molar ratio of 10 : 1, initial samples of multiblock poly(ester imide) and its composites with nanoparticles of two types—zirconia ZrO2 surface-treated with γ-aminopropyltriethoxysilane and zirconia doped with yttria (Y0.03Zr0.97O1.985)—are synthesized. Nanoparticles are introduced into the polymer matrix at the stage of synthesis of the poly(ester imide) prepolymer. The mechanical properties of films of poly(ester imide) and its nanocomposites are determined under static and dynamic testing conditions, and the permeabilities and separation selectivities of corresponding solid films for mixtures of aromatic and aliphatic hydrocarbons (toluene-n-octane and benzenecyclohexane) of various compositions are measured under pervaporation testing conditions. It is shown that the different mechanical and pervaporation properties of film samples are due to the presence of zirconiabased nanoparticles.

The efficient sensitization of the photoelectric effect in mixed compositions of poly(phenylquinoline)s (PPQ) with 2,1,3-benzothiadiazole (BTDZ) molecules is established. The introduction of 10 wt % BTDZ results in extension of the spectral sensitivity range of PPQ and an increase in the photosensitivity and photocurrent by factors of 4.5 and more than 6, respectively. It is shown that the effect is caused by complex formation between PPQ donor fragments and BTDZ acceptor molecules; the strongest, in comparison with the increase in photosensitivity, is probably caused by the transport of free photogenerated carriers (electrons) over sensitizer molecules introduced into the polymer.

The photophysical and electrical properties of copolymers based on 2,6-polyphenylquinolines containing a bridging oxygen or phenylamine group between quinoline rings and octyl- or dodecylcarbazole or dioctylindolo[3,2-b]carbazole fragments in the aromatic radical are studied. It is shown that the introduction of carbazole and indolo[3,2-b]carbazole fragments emitting in the visible spectral range into the aromatic radical of a copolymer makes it possible to obtain white luminescence. The intensity of this luminescence exceeds, for copolymers in a photoinert matrix, that of the initial homopolymers. This circumstance, combined with rather high carrier mobilities on the order of 5 × 10−6 cm2 V−1 s−1, makes the copolymers promising for the development of electroluminescent devices on their basis.

Thermal, deformation-strength, and dynamic mechanical properties of films of segmental polyesterimides prepared from pyromellitic anhydride, aromatic diamines, and poly(butylene adipate) (M n = 1000) with hydroxy terminal groups were studied. The glass transition points T g of the samples obtained are below 0°C. The dynamic elastic modulus curves at temperatures higher than T g are characterized by a portion in which the modulus only weakly depends on temperature.

The energy structure and nature of intramolecular charge transfer have been determined for a series of synthesized 2,6-polyphenylquinolines (PPQs) containing resorcinol, oxygen, and phenylamine bridging groups between phenylquinoline cycles and possessing an arylene radical in the form of alkylated derivatives of carbazole or indolo[3,2-b]carbazole, as well as arylated derivatives of carbazole with nitro- and fluorine substituents. The analysis was based on data on their absorption spectra, photosensitivity, carrier photogeneration quantum efficiency, and luminescence. It is shown that the PPQ monomeric unit is a composite intramolecular charge-transfer complex (ICTC) between the donor arylene fragment and the acceptor quinoline cycle; the latter, in turn, is an ICTC between the donor bridging group and quinoline ring (when acceptor fluorine or nitro substituents are introduced into the carbazole structure, the complex becomes ternary), and the narrowest band gap (2.3 eV) corresponds to the PPQ having a phenylamine bridging group and a fragment of indolo[3,2-b]carbazole.

The surface structure of Langmuir-Blodgett films of a comblike polyimide precursor—a rigid-chain polyamic acid alkylamine salt bearing multichains of tertiary amine—and films of the corresponding polyimide were studied by atomic force microscopy (AFM). An analysis of the images of the surface of three-layer films revealed a domain structure. It was found that the Langmuir-Blodgett film formation of the precursor occurs as a result of the layer-by-layer deposition of two-dimensional domains (composed of polyamic acid salt molecules on the water surface) onto a substrate. The formation of domains in a monolayer is associated with the chemical structure of the precursor, to be more precise, with the rigidity of the main chain and the presence of closely spaced aliphatic side chains in the polymer chain, whose total cross-section area is close to the surface area of the projection onto the plane of the repeating unit of the main chain. Polyimide films inherit the domain structure of the precursor films; the inhomogeneity of the film thickness substantially decreases, whereas the domain size and character of their distribution in the film remain unchanged.

Photophysical and electrical properties of new synthesized 2,6-polyphenylquinolines (PPQs) containing an oxygen or phenylamine bridging group between quinoline cycles and, as an arylene radical, alkylated derivatives of carbazole or indolo[3,2-b]carbazole are studied. It is shown that the photosensitivity for new PPQs is 104–105 cm2/J and the photogeneration quantum yield of free carriers is as high as 0.15. Photophysical parameters increase with the phenylamine bridging group in place of the oxygen one and when using indolocarbazole instead of carbazole. It is found that a film of polyphenylquinoline containing an oxygen bridging group and an alkylcarbazole fragment in the polymer repeat unit exhibits “white” luminescence. Both electron and hole transport with a mobility of ∼10−6 cm2/(V s) are detected in films of all studied polymers. The conductivity value and type can be controlled by varying the chemical structure of the (oxygen or phenylamine) bridging group between PPQ cycles and by choosing carbazole or indolo[3,2-b]carbazole derivatives as an arylene radical.

The photophysical properties of new synthesized indolocarbazoles, i.e., indolo[3,2-b]carbazole and its derivatives, have been comparatively analyzed. It is shown that their photosensitivity (total photosensitivity to (5–8) × 10−2 (lx s)−1, spectral photosensitivity ∼105 cm2 J−1, and free carrier photogeneration quantum yield of 0.1) and transport (effective mobility in 5,11-dioctyl indolo[3,2-b]carbazole is more than 10−5 cm2/(V s)) parameters significantly exceed those of pentacene, which, among molecular media (organic crystals), exhibits the highest carrier photogeneration quantum yields. The high photoluminescence intensity of synthesized indolo[3,2-b]carbazole derivatives shows promise for their applicability in electroluminescent devices.

Morphology of microporous films prepared from aromatic polyamidoimides under different molding conditions was studied by scanning, transmission, and atomic force microscopy with the specific attention given to the nanosize skin layer. The films were manufactured by the phase inversion molding of aromatic polyamidoimides which were synthesized by low-temperature polycondensation of phthalimidobenzenedicarbonyl dichloride with various diamines. Comparison of the parameters of films, including their wettability and X-ray photoelectron spectroscopy data, gave additional information on factors affecting the mechanism of formation of microporous membranes in the system polymer (polyamidoimide)-solvent (N-methylpyrrolidin-2-one)-non-solvent (water).

For films based on poly(amidoimide) with a comb-shaped structure and long side chains, the specific features of the mechanical and thermomechanical behavior and their dependence on the concentration of the above chains are studied. With variation of the composition of the material, changes in the mechanical characteristics show a nonmonotonic character. Comparison of the results of mechanical tests and densimetric measurements allows certain conclusions to be drawn about the character of variations in the structural organization of films with an increase in the concentration of side fragments in macrochains. The role of plasticization in the behavior of the above materials during heating is demonstrated. The advantages of the practical use of the above phenomena for the optimization of the regimes of thermally stimulated polarization of films are discussed.

The Langmuir monolayers and Langmuir-Blodgett films of a comb-like polyimide prepolymer (the rigid-chain polyamic acid alkylamine salt bearing multichains of tertiary amine) were studied. The supramolecular structures of the monolayers and Langmuir-Blodgett films of polyamic acid salts were characterized and a way for the surpamolecular structure to form was proposed based on an analysis of the surface pressure-area isotherms of monolayers on the water surface, investigations of the conditions of monolayer deposition onto solid substrates, and studies of the structures and surface morphology of Langmuir-Blodgett films.

A procedure is developed for preparing conducting films by their casting from polymer solutions containing polyaniline in the form of a protonated emeraldin base and polyimides in two cosolvents, N-methylpyrrolidone or m-cresol. Self-supporting films cast from composites based on polyimides and camphorsulfonic acid-protonated polyaniline combine a conductivity of 10−1−10−2S/cm with good mechanical properties: elastic modulus E = 2.0−2.4 GPa, breaking strength σb = 55−60 MPa, and elongation at break ɛb = 8−10%. It has been shown that, when m-cresol and N-methylpyrrolidone are used as cosolvents, the maximum film conductivity is achieved at polyaniline amounts in the composites of 20 and 3%, respectively. In the latter case, films with good strength parameters are formed.

Photoelectric and electrical properties of polyphenylquinolines differing in the structure of donor bridge groups between quinoline moieties have been studied. It is demonstrated that films of the polymers synthesized exhibit a photosensitivity at the level of 105 cm2 J−1 (integrated sensitivity 5 × 10−4 lx−1 · s−1), with a quantum yield of carrier photogeneration of 0.07 and a carrier drift mobility on the order of 10−6 cm2 V−1 s−1. The fact that the electron and hole drift mobilities in polyphenylquinoline with a phenylamine bridge group are balanced makes the polymer promising for development of film-type devices based on the bipolar conductivity of a material (e.g., single-layer light-emitting diode).

Soluble polyimides containing triphenylamine residues as substituents at the imide nitrogen atom and polyquinazolones with diphenyl oxide, diphenylpropane, benzimidazole, benzoxazole, benzothiazole, oxadiazole, and triphenylamine moieties in the diamine component of the repeating unit have been synthesized. The spectroscopic study of polyquinazolones indicates their capability for donor-acceptor interactions. Emission bands of the polymers are of the exciplex nature. The photogeneration of current carriers in the polymers under study has been examined by the method of surface potential photoinduced decay. It has been shown that the intrinsic photosenitivity of polyquinazolones is nearly the same as (or somewhat higher than) that of the corresponding polyimides, but the former polymers are characterized by a less efficient spectral sensitization by dyes and donor-acceptor additives.

The local forms of molecular mobility of comb-shaped random copoly(methacrylates) have been studied by the method of dielectric spectroscopy. Side branches of these copolymers are composed of alternating chromophore-containing chains and flexible fluoromethylene sequences. Two regions of relaxation of dipole polarization, γ2 and β processes, related to the mobility of end polar groups and the reorientation of chromophore groups relative to their long axes, respectively, have been discovered in the glassy state. The times of relaxation of the γ2 process depend on the ratio between the flexible and rigid parts of the copolymer. In the region of the β process, the molecular mobility appears to be slightly dependent on the chromophore structure and its intensity is determined by the degree of substitution of chromophore groups.

Electrochemical approach to a new electroactive catalytic system based on polyamic acids with biquinolyl (biQ) fragments in the polymer backbone capable of coordination to Cu(I)-ions was elaborated using sacrificial Cu anode. The redox properties of the resultant Cu(I) polymer complex were characterized by voltammetric methods. Polynuclear Cu(I) complex with only one biQ ligand per Cu(I) center showed high oxidase activity in air oxidation of aliphatic and aromatic alcohols to corresponding carbonyl derivatives with concomitant reduction of molecular oxygen to water. The reactions proceed in acetonitrile or N -methylpyrrolidone at a potential of Cu II /Cu I electroreduction (−0.55 V versus Ag/AgCl/KCl) with the high preparative yield and current efficiency. The electrocatalytic efficiency is enhanced when the Cu-containing polymer is immobilized on the graphite surface. The stoichiometric composition of the adsorbed polymer complex was determined by means of coulometric assays of the quantities of electroactive biQ fragments and Cu(I) present on the surface. The possibility of the obtained redox-active macromolecules to mimic the active site of certain copper-containing enzymes capable of reversible binding and activation of dioxygen is discussed, providing some insight into the mechanism of the catalytic process.

The photosensitivity of conducting polymer films with newly synthesized polymethine dyes is investigated. It is demonstrated that the photosensitivity of polymer films based on poly(o-hydroxyamide) with transport indole molecules forming intermolecular complexes with dyes is two or three times higher than the photosensitivity of the polymer films containing indole as a structural component of the dye. The introduction of the indole-containing dye into the photoconducting poly(vinylcarbazole) leads to an increase in the photo-conductivity by one and a half orders of magnitude. In this case, the quantum yield increases to η = 0.085. A correlation is revealed between the electronic structure of the dyes, the characteristics of the photoconduction in the materials under investigation, and the mechanisms of charge relaxation in the samples. An increase in the photoconductivity of the films results in the crossover from the drift mechanism of charge relaxation to the relaxation mechanism associated with intrinsic electrical conduction.

Method of electrochemical synthesis of new Cu-containing polyheteroarylenes that have biquinolyl units in their main chain is developed on the base of the soluble anode technique. The study of electrochemical properties of thus obtained Cu-containing polymer and the corresponding monomer complex revealed existence of two types of coordination environment: (1) copper Cu(I) in the tetrahedral surrounding of two biquinolyl ligands and (2) copper Cu(I) bound with only one biquinolyl fragment. The complexes with one biquinolyl polymer ligand showed high activity as catalysts for O2 reduction in the presence of hydroquinone that is converted to quinone in the course of the reaction.

A number of styrylquinoline chromophores with carboxyl groups have been prepared through the interaction of 2-methylcinchonic acid with aromatic aldehydes of various chemical structures. The copolymer of glycidyl methacrylate and methyl methacrylate carrying side epoxide groups has been synthesized, and the chemical modification of the copolymer with the above chromophores has been performed. The thermal, spectral, and nonlinear optical properties of the chromophores and modified polymers have been studied.

Structural reorganization of polyamide (PA) and low-molecular-weight CuI and CuII complexes with biquinolyl (biQ) ligands during their mutual redox transformations in solution was studied using the electrochemical methods (cyclic voltammetry and preparative electrolysis) and quantum chemical DFT calculations. The influence of electronic factors and geometry distortions in the complexes on the ionization energy on going from CuI to CuII was evaluated in comparison. The catalytically active form of the [CuI(PA)L2]BF4 complex can be synthesized in situ from the stable tetrahedral complex [CuI(PA)2]BF4 by the series of successive redox transitions CuI → CuII → CuI accompanied by the loss of one biQ-containing macroligand.

The molecular mobility of copoly(methacrylates) with chromophore-containing side groups of various structures has been studied by the dielectric method. The region of relaxation of dipole polarization related to the segmental mobility (α process) has been discovered. At temperatures that are ∼30°C higher than those corresponding to the α process, the relaxation transition reflecting the reorientation of chromophore-containing side groups (δ process) takes place. It is suggested that the occurrence of the δ process is a general phenomenon for such systems. This effect allows one to determine the temperature at which the polarization of polymer films under application of corona discharge should be carried out so that a high level of nonlinear optical properties associated with the macroscopic noncentrosymmetrical orientation of chromophores may be achieved.

Complexes Eu(TTA)3phen and Eu(MBTA)3phen, as well as complexes Tb(MBTA)3phen and Tb(TTA)3phen, which do not luminesce in solutions, are shown to luminesce in polymer films (TTA is thenoyltrifluoroacetone, MBTA is n-methoxybenzoyltrifluoroacetone, and phen is o-phenanthroline). Luminescence of complexes of Eu and Tb in films of a polymer, poly(methylene-bis-anthranilamide) 1,6-hexamethylenedicarboxylic acid (PAA-5), having a high concentration of functional anthranilate groups, is studied. From the behavior of the luminescence intensity (I lum), the luminescence decay time, and the luminescence spectra of complexes of these lanthanides in polymer films, the following regular features were revealed. (i) During the film preparation at 90°C, Ln complexes are attached to PAA-5 via anthranilate groups. (ii) Irradiation of these films in the range of the absorption band of ligands (TTA or MBTA) leads to deactivation of the electronic excitation of ions according to the diketone detachment mechanism and to further binding of complexes to polymers. In this case, I lum(Eu(III)) decreases because the introduction of anthranilate groups of the polymer into the first coordination sphere of Eu(III) complexes enhances the nonradiative deactivation of these ions, whereas I lum(Tb(III)) increases since the introduction of these groups suppresses the nonradiative deactivation of Tb complexes through triplet states of ligands (TTA and MBTA). (iii) Upon storage of films in the dark (20°C), complexes detach themselves from the polymer and return to their initial structure. In PAA-5 films into which Eu and Tb complexes were simultaneously introduced, the color of the emission from the irradiation spot changes from red to green.

The structure of mixed amide solvents used for the preparation of polyimide Langmuir-Blodgett films and the structural organization of water, on which nanofilms are formed, have been studied by polarized light scattering. Fluctuation supramolecular structures are found to exist in water and in its mixtures with amide solvents, and the dimensions of the structures are comparable with the light wavelength. When a mixture contains more than 20 vol % water, associates show microanisotropic properties. In snowmelt water, the dimensions of associates are larger than those in distilled water. In the DMAA-water mixture, the dimensions of supramolecular structures are virtually independent of composition.

For a set of comblike polymers manufactured by polymer-analogue conversions, nonlinear optical and photosensitive properties are investigated. On the basis of the chemical modification, the interaction between polyamidoimides with side carboxyl groups with glycidyl ethers of commercially manufactured azo dyes (DR-1, DO-13, DY-7) is used. It is shown that transparent films of these polymers have a reasonably high electrophotographic photosensitivity (at a level of 104 cm2/J), and the coefficient d 33 of second-harmonic generation describing nonlinear optical properties is within 4.5–6 pm/V.

A series of composite materials of a new type — foam organoplastics — was obtained from foamed polyimide binders reinforced with Arimid T polyimide felt, and commercially available aromatic monomers were used. Use ofDPO (3,3′,4,4′-diphenyloxidetetracarboxyic acid) dianhydride in the H-complex allows obtaining a melt of lower viscosity (300 Pa-sec), and the viscosity almost does not change at 95°C for 20 min. The viscosity of melts of the H-complexes based on BZP (3,3′, 4,4′-benzophenonetetracarboxylic acid) tends to increase rapidly to the level of 105 Pa·sec, probably due to further “crosslinking” of the H-complex in the conditions of the melt. Replacing the carcinogenic 4,4′-diaminodiphenylmethane (DADPM) diamine by commercially available 4,4′-diaminodiphenyl ether (DADPE) does not significantly alter the rheological behavior of the H-complex melt at 95°C and does not decrease the mechanical characteristics of the foam composites. The mechanical characteristics (bending strength, compressive and shear moduli) of the foam composites based on H-complexes with DPO dianhydride are 1.5 times higher than for the same foam composites using BZP dianhydride. The foam composites based on DPO do not undergo brittle failure but simply bend in bending tests, which can be used to obtain new elastic foam materials. The effect ofnanoparticles on the properties of the foam composites was established. It is expedient to use montmorillonite nanoparticles, which increases the modulus of elasticity and rigidity of the material.

Morphology of asymmetric membranes based on poly((diphenyl oxide amido)-N-phenylphthalimide) was studied by scanning electron microscopy, transmission electron microscopy, and atomic force microscopy. The effect of preparation conditions on the morphology and transport properties of the membranes was investigated. The test membranes were prepared by the phase-inversion method under the conditions of “wet” casting in the polymer-solvent (N-methyl pyrrolidone)-nonsolvent (water, ethanol, 2-propanol, or aqueous alcohol solutions) systems. Feed casting solutions with a concentration of 10–14 wt %, including those containing a weak nonsolvent (ethyl acetate) were used. A comparative analysis of the structural features and water permeability of the test membranes allows the conclusion that some types of membranes can be used in nanofiltration processes.

With the use of light scattering and viscometry, as well as the employment of various aprotic solvents for the polymer synthesis, the molecular characteristics of two poly(amic acids), namely, poly[4,4′-bis(4″-N-phenoxy)diphenylsulfone]amic acid of 1,3-bis(3′,4-dicarboxyphenoxy)benzene and poly[4,4′-bis(4″-N-phenoxy)diphenyl]amic acid of 1,3-bis(3′,4-dicarboxyphenoxy)benzene, have been studied at various molar ratios of the starting reagents and concentrations of the polycondensation solution. The molecular masses of poly(amic acids) depend on the thermodynamic quality of a solvent which may be changed by varying the nature of the solvent, the structure of the resulting polymer, or the chemical nature of the mixture.

Soluble poly(amido imides) and copoly(amido imides) containing main-and side-chain chromophore chalcone groups have been synthesized. Thermo-and photocrosslinking of polymer chains in films under UV irradiation have been studied. The mechanical properties, dielectric behavior, and photosensitivity and photoconductivity characteristics of the polymers have been investigated.

Structural organization is studied for dilute solutions of the comblike N,N-dimethylhexadecylammonium salt of polyamic acid based on 3,3′,4,4′-diphenyltetracarboxylic dianhydride and o-tolidine by the method of polarized light scattering in mixed dimethylacetamide-benzene and N-methylpyrrolidone-benzene solvents. The statistical structural parameters of the solutions are calculated according to the Debye-Stein theory. The dimensions of ordered scattering fluctuation-type formations are shown to be much greater than the molecular dimensions and to depend on the chemical nature and composition of the mixed solvent. At polymer concentrations below 0.2 g/dl, the corresponding concentration dependences of the statistical structural parameters are characterized by extreme patterns for all systems under study.

New polyamic acids with biquinoline units in the backbone, which are prepolymers of polybenzoxazinones, as well as their metal-polymer complexes containing [Ru(bpy)2]2+, were prepared. The electronic structure of these polymers was studied with the use of cyclic voltammetry, electronic absorption spectroscopy, and quantum-chemical calculations, and the location sites of electronic changes upon electrochemical reduction and oxidation were determined.

A series of foamed organoplastics based on a combination of foamed fully aromatic polyimide binders and Arimid T polyimide felt were prepared. New composite foamed organoplastics reinforced with montmorillonite nanoparticles were prepared using commercially available aromatic monomers.

The emission bands exchibited by films of polyimides derived from 1,3-bis(3,4-dicarboxyphenoxy)benzene dianhydride, hexafluoroisopropylidenedibenzene-3,3′,4,4′-tetracarboxylic dianhydride, and aromatic and heteroaromatic diamines, and also of polyamides and polyquinazolones derived from the same amines are exciplex bahnds. With polyamides, complexes in the ground state are formed. The fluorescence of the photoconductivity sensitizer Rhodamine 6G is quenched in films of these polymers by the exciplex mechanism.

The time change in the melt viscosity of the polyamide composite forming at the final stage a polymer with the structure of a semi-interpenetrative polymer mesh has been investigated. To impregnate with the composite melt the carbon fiber for forming carbon-filled plastics, it is necessary to preserve the low viscosity of the melt for a long time. This is achieved by preliminary heat treatment of the composite and introduction of fullerene into it.

Atomic-force microscopy, reflectometry, and ellipsometry were applied to analysis of ultrathin films (3.3–13.6 nm) of a rigid-chain polyimide, formed on the surface of a silicon substrate by thermal imidization of Langmuir-Blodgett films of polyamido acid derived from 3,3′,4,4′-diphenyltetracarboxylic acid and ortho-tolidine.

New polyamide acids (prepolymers of polybenzoxazinimides) containing 2,2-biquinolyl units in their main chain are synthesized. It is shown that these polymers form stable complexes with acids derived from the transition and rare-earth metals. The results of photophysical studies support the assumption that the process of generation of free charge carriers via a state of a pair bound by a Coulomb interaction includes two stages and that metal-polymer complexes are involved in this process. The quantum yield of photogeneration amounts to 0.007–0.05.

The structures have been analyzed of the monolayers of comblike precursor polymers of polyimides and mixed cellulose esters formed at the water/air interface and of the Langmuir-Blodgett films obtained by transfer of these condensed monolayers onto solid substrates. The important factors that ensure the structure control and supramolecular organization of these monolayers and films are established.