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A new method was suggested for preparing aromatic polyphenylquinazolones by thermal polyhet-erocyclization of polyamidines containing free carboxy groups. The structure of the polyphenylquinazolones obtained was confirmed by elemental analysis and IR spectroscopy. The polymers obtained are soluble in a wide range of organic solvents and resistant to thermal and thermal oxidative degradation; they exhibit high deformation and strength characteristics. Such properties make these polymers promising for processing into various items by traditional methods.

Polynaphthoylene benzimidazole and polybenzimidazole were obtained via polycondensation of 2,3,7,8-tetraaminodibenzo-p-dioxin with aromatic di- and tetracarboxylic acids in polyphosphoric acid. From a solution of polynaphthoylene benzimidazole in methanesulfonic acid a heat-resistant fiber with high tensile strength was obtained. Aromatic polybenzimidazoles are promising materials for producing membranes of medium-temperature fuel cells.

A method for the synthesis of hydrogels of poly(hexamethyleneguanidine hydrochloride) that is based on the interaction of polymer amino end groups with aldehydes is proposed. With the use of physicochemical analysis, the structures of crosslinked polymers are determined, the sensitivity of hydrogels to changes in the pH of medium is considered, and a preliminary study of their application as stimulators of the reparative regeneration of a cutaneous covering is conducted.

The study aims to obtain polyhexamethylene guanidine hydrochloride hydrogel compositions with extracts of medicinal plants growing in the Baikal region (Bergenia crassifolia, Calendula officinalis, Tussilago farfara) to evaluate sorption activity and consider the subsequent use of the compositions as an external wound healing agent. It has been shown that hydrogel sorbs mainly caffeinequinic acids in various compositions. It has been made an assumption about a link of sorption process with formation of secondary amino groups’ complex in the hexahydrotriazine cycle, which is formed as a result of gelation of PHMGhch, and carboxyl groups of extract substances. It is planned to study the wound healing activity of compositions by modeling skin damage of laboratory animals in future researches.

The one-step interaction of 1H-benzotriazoles with maleimides in melt at elevated temperatures has resulted in benzotriazolylsuccinimides. According to spectroscopy data, benzotriazolylsuccinimides obtained contain both major (benzotriazol-1-yl)-succinimide residue and minor (benzotriazol-2-yl)-succinimide residue. An effect of substituents in the initial reagents on the fine splitting of carbon peaks in 13C NMR spectrums of benzotriazolylsuccinimides is discussed. The influence of structure of benzotriazolylsuccinimides on their crystallinity degree is also discussed.

Polymers with amidine groups -NH-C(=NH)- in main chain were synthesized by two different approaches. The first strategy consists in polyaddition of dinitriles and diamines in acidic ionic liquids (ILs) which act as catalyst and sol- vent, while the second approach is based on polycondensation of 4,4!-oxybis(benzoic acid) diamide and diamines in Eaton's reagent (ER). The resulting polyamidines (PADs) with Mw up to 25 000 g/mol possess thermal stability on air up to 288°C, and good solubility in polar organic solvents. Moreover dehydrocyclization of obtained PADs into polybenzimida- zoles (PBIs) under the action of various oxidants was also studied in this work. The crosslinked films based on PBI and poly(amino imide) resin (PAIR) possess high mechanical characteristics. It has been proved that the crosslinked films based on PBI matrix are perspective materials for design the phosphoric acid electrolyte membranes for the medium temperature fuel cells.

The published data on the chemical and physical modifications of cellulose aimed at creation of a wide variety of new innovative materials for hi-tech and priority directions in the development of science and engineering are summarized. Investigations into the chemical modification of cellulose via nucleophilic substitution, regioselective insertion of functional groups, graft copolymerization, oxidation, and esterification are covered. The importance of studies dealing with the search for new solvents of cellulose aimed at extension of the potential inherent in its modification and processing and in the design of nanocellulose-based materials is emphasized. On the basis of analysis of the literature data, the potential for creation of new functional materials for biomedical investigations, medicine, and electronics is shown.

Dehydrocyclization of polyamidines into polybenzimidazoles under the action of various oxidants was studied. The strength and proton conductivity of membranes based on a blend of the polybenzimidazole obtained with poly(amino imide) resin were determined.

Acyclic polyimides are prepared for the first time through the interaction of imidoyl chlorides and dicarboxylic acids. This transformation passes through the formation of polycarboxyimidates, which, depending on the temperature of reaction, rearrange in situ via the Mumm-Hess mechanism or during subsequent heating to yield the target product. The polymers thus prepared show high solubility and thermal stability (380–450°C).

A possibility for the transformation of polyphenyl imidates, obtained by polycondensation of bisphenols with imidoyl chlorides of mono- and dicarboxylic acids, into N-phenyl-substituted aromatic polyamides and poly(N-benzoylamines) has been discovered. Such a rearrangement resulted from heating at 260–340 °C for 13–17 h, whereas in diphenyl ether solution at 240 °C for 10–14 h. The polymers synthesized are soluble in organic solvents and possess high stability against thermooxidative destruction.

It is established that N-phenylsubstituted aromatic polyamides can be obtained via Chapman rearrangement of polybenzanyliminoesters synthesized by an interaction of bisphenols with imidoylchlorides. The rearrangements in melt or in film occur as a result of heating at 260–340 °C, and in a diphenyl ether solution rearrangement occurs at 240 °C. The resulting polymers are soluble in organic solvents and demonstrate high thermooxidative stability. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 4656–4660, 2007

It is shown that polyimidates obtained by polycondensation of bisphenols with imidoyl chlorides may be transformed into N-phenylsubstituted aromatic polyamides. The rearrangement occurs as a result of heating at 260–340°C, and, in a diphenyl ether solution, at 240°C. The resulting polymers are soluble in organic solvents and demonstrate high thermooxidative stability.

New amidine-containing polymers were prepared by the polycondensation of aromatic diamines with bis(imidoyl) chlorides in polar organic solvents in the presence of various catalysts (triethylamine, tributylamine, and pyridine N-oxide). Optimal synthesis conditions, namely, temperature, duration, concentration of monomers and catalyst, and the order of reagent loading, were established. The structure of polyamidines was studied by elemental analysis and IR and NMR spectroscopy. When the polymers were heated to 250°C in vacuum, their molecular masses increased.

Aromatic polyamidines are prepared via the polycondensation of dicarboxamides and diamines in Eaton’s reagent. The polymers are investigated by elemental analysis and IR and NMR spectroscopy. Polyamidines are well soluble in concentrated sulfuric acid and concentrated formic acid and in polar organic solvents, and temperatures corresponding to their 10% weight losses are in the range 245–280°C.

New polyimidates were prepared from bisphenols and mono- and dicarboxylic acid imidoyl chlorides. The structures of the polymers were determined, and their physicochemical, chemical, and thermal properties were studied. The possibility of preparing film and compression materials with good mechanical characteristics from these polymers was examined.

A frost-resistant polyamidobenzimidazole-based polymer composite is synthesized from 3,3',4,4'-tetraaminodiphenyl oxide, diphenyl adipate or diphenyl sebacate, and hexamethylenediamine or e-caprolactam. As stabilizers for the polymers were used 4-phenyl-2,2,5,5-tetramethyl-3-imidazoline-3-oxide-1-oxyl and carbon black.

Cross-linking of Novolac resin with aromatic dinitriles in the presence of aluminum chloride was studied.

The mechanism of rearrangement of polycarboxyimidates prepared by the reaction of dinitriles with dicarboxylic acids at elevated temperature was studied. The solubility of the resulting acyclic polyimides was determined.

Polyamidobenzimidazoles derived from 3,3′,4,4′-tetraaminodiphenyl ether, diphenyl esters of aliphatic and aromatic dicarboxylic acids, and ɛ-caprolactam were prepared by solid-phase polycondensation. The relative degree of crystallinity, imparting the plasticity to the polymers as compared to the corresponding polybenzimidazoles, was determined by X-ray phase analysis.

The transformation of polyarylene benzimidates prepared by polycondensation of bisphenols with benzimidoyl chlorides in N-methyl-2-pyrrolidone into poly(N-arylenebenzamides) was studied.

Thermostable high-molecular polybenzimidazolimides have been prepared by a reaction of bis-benzimidazoles with bis-maleimides at 110–120°C in DMFA in the presence of organic acids. The obtained polymers are lightly coloured substances, soluble in amide solvents, DMSO, and in formic and sulphuric acids. Their structure has been confirmed by elemental analysis and IR spectroscopy. As moulded products they exhibit good dielectric and mechanical properties.

Aromatic polyamides were synthesized by the reaction of dinitriles and bisphenols at 160–220 °C for 12–20 h in the presence of catalytic amounts of aluminum or antimony(III) chlorides. The polymers are completely soluble in concentrated sulfuric and formic acids at room temperature and in DMAA, DMF, and DMSO on heating.

New N,N′-bisimides were synthesized by condensation of polynuclear aromatic diamines with maleic anhydride. The obtained N,N′-bisimides are crystalline yellow-coloured compounds, soluble in acetone, dioxan, amidic solvents, organic and inorganic acids. Their structure was identified by elemental analysis, NMR and IR spectroscopy. The N,N′-bisimides were polycondensated with diamines in cresol solution to high polymers. Neue N,N′-Bis-maleinimide wurden durch Kondensationsreaktion von mehrkernigen aromatischen Diaminen mit Maleinsaureanhydrid synthetisiert. Die erhaltenen N,N′-Bis-maleinimide sind kristalline, gelb gefarbte Verbindungen, die in Aceton, Dioxan, Amidlosungsmitteln sowie in organischen und anorganischen Sauren loslich sind. Ihre Struktur wurde durch Elementaranalyse, NMR- und IR-Spektroskopie identifiziert. Die N,N′-Bis-maleinimide wurden in Cresol-Losung mit Diaminen zu Polymeren polykondensiert.

Members of a new class of compounds, di-imidodicarboxylic acids, containing six-membered imide rings, have been synthesized by reacting 4-carboxynaphthalic anhydride with aromatic diamines. Polycondensation of these acids with aromatic tetramines in polyphosphoric acid produced poly(benzimidazole imides), notable for their high resistance to acids and bases. Some properties of these polymers were investigated.

New thermally stable polymers that contained benzimidazole and benzimidazobenzoisoquinoline fragments in polymer chains were synthesized by one-stage cyclopolycondensation of aromatic tetramines (3,3′, 4,4′-tetraminodiphenyl ether, 3,3′,4,4′-tetraminodiphenyl methane, 3,3′,4,4′-tetraminodiphenyl sylfone, and 3,3′-diaminobenzidine) with 1,4,5-naphthalene tricarboxylic acid 4:5–anhydride in polyphosphoric acid and with 1,4,5-naphthalene tricarboxylic acid 4:5–anhydride 1-phenyl ester. All polymers obtained were soluble in concentrated sulfuric acid, 85% phosphoric acid, polyphosphoric acid, methane sylfonic acid. Some were soluble in formic acid. Thermogravimetric analyses indicated that these polymers were stable up to 450–500°C in air. The polymers had good hydrolytic stability.

An investigation was made of the thermal and thermooxidative decompositions of polybenzimidazopyrrolones and polybenzimidazobenzoquinolines, as well as a number of heterocyclic compounds modelling the linkages and individual fragments of these polymers. It was established that in the pyrolyses of the polyheteroarylenes and the corresponding model compounds the destruction of cycles occurs either simultaneously with cleveage of the Car-H bond or at a higher temperature. It was shown that the completely aromatic compounds and the heterocyclic compounds condensed with the benzene nucleus are the most thermostable of the investigated compounds. A comparative study revealed a correlation between the structures and thermal stabilities of the studied compounds.

Heat-resistant polymers have been prepared from 4-phenyl naphthalenetricarboxylic acid anhydride and aromatic tetramines by polycondensation in the melt. Some relationships of the reaction have been studied and the optimal conditions of preparation have been found. These polymers are soluble and are highly resistant to thermal-oxidative degradation. Dynamic thermogravimetric analysis showed that the temperature of decomposition in air is above 400°.