Published data on methods for the preparation of liquid crystalline phenyl benzoate derivatives were summarized. The results of studies on the mesomorphic properties of phenyl benzoates were analyzed. The available literature and authors' research data on the application of mesogenic phenyl benzoate derivatives in medicine and in the chemistry of macroheterocyclic compounds, as well as in polymer chemistry and technology were presented.

The stationary phase for gas chromatography on the basis of the chiral R (+)-1′,7′,7′-trimethylbicyclo-[2.2.1]heptano[2′,3′- b ]-2,3-dicyanopyrazine (10.4 wt %) and a liquid crystalline 4,4′-dihexyloxyazoxybenzene was studied. The phase transition temperatures of the binary mixture were measured by polarizing microscopy. It was shown that the chiral camphor-substituted 2,3-dicyanopyrazine induces formation of an enantiotropic chiral helically coiled nematic phase in the achiral liquid crystal over a wide temperature range. The gas chromatographic retention times of organic compounds on this sorbents were measured. The structural and chiral selectivity of the stationary phase on the basis of a liquid crystal and camphor-substituted 2,3-dicyanopyrazine was determined. The retention volumes, activity coefficients, and sorption enthalpies and entropies were calculated and analyzed.

Using the percolation reinforcement model, it has been shown that the main factor governing the degree of reinforcement of polymer/2D-nanofiller composites is the ability of a nanofiller to generate interfacial regions. This parameter is interrelated with two fundamental structural characteristics of a nanocomposite, i.e., the fractal dimension of its structure and the content of polymer matrix/nanofiller interfacial surfaces. The negative effect of high nanofiller anisotropy on the elasticity modulus of a nanocomposite is demonstrated.

The published data on the preparation of cellulose nitrate are summarized. New sources of cellulosic materials are analyzed. The results of studies on the chemical modification of cellulose nitrate by nucleophilic substitution are presented. The published data on the plasticization of cellulose nitrate are summarized. Modern plasticizing systems and methods for their effectiveness assessment are described.

Методом дифференциально-сканирующей калориметрии показано, что 4-(4-{4-[2-гидроксиэтилокси]бензоилокси}-фенилдиазенил)бензальдегид (ГЭОФДБ) является энантиотропным высокотемпературным нематиком с широким интервалом существования мезофазы. Методом газовой хроматографии исследована сорбция из газовой фазы 8 органических соединений кристаллической и нематической фазами ГЭОФДБ. В качестве сорбатов выбраны электронодонорные изомеры метилпиридина и диметилпиридина, изомеры слабополярных ксилолов и крезолов. Рассчитаны удельные удерживаемые объемы сорбатов и критерии их разделения. Обсуждается влияние температуры и химической природы сорбатов на их сорбционное перераспределения в системе газ – жидкий кристалл. Установлено, что сорбент на основе ГЭОФДБ проявляет высокую селективность по отношению к близкокипящим органическим соединениям различной природы, а также хорошую эффективность и производительность при их разделении. Ключевые слова: газовая хроматография, мезоген, стационарная фаза, сорбат, удельный удерживаемый объем, фактор разделения.

The lubricity of 4-acryloyloxyphenyl ester of 4'-n-octyloxybenzoic acid and the system composed of p-n-propyloxybenzoic acid and p-n-propyloxy-p'-cyanobiphenyl in the conditions of boundary friction was investigated. The studies were carried out both for pure substances and their solutions in the liquid paraffin base. It was established that the studied additives possess good tribological properties. The tribological activity is defined by chemical structure and concentration of the additive in solution. The presence of the triboactive additives in lubricant stabilizes tribological properties of the lubricant on heating.

Azo-functionalised materials are of special interest due to their photochromic nature, i.e. reversible trans-cis isomerisation upon photoirradiation. The structure and properties of Langmuir monolayers of nonyloxyphenylazocinnamic acid (NOPACA) with and without exposure to UV-irradiation were studied. The NOPACA floating layer structure was determined by using a quantitative method of compression isotherm analysis. The results showed that the structure of two dimensional face-on M-nanoaggregates, the stable structural elements of floating monolayers, changes when exposed to UV-irradiation. Langmuir-Schaefer films of NOPACA were prepared by deposition of floating layers and studied using X-ray diffraction technique.

The rheological properties of nitrocellulose solutions in cyclohexanone in the presence of phthalic and 4-nitrophthalic diester plasticizers were studied by rotational viscometry to reveal a behavior similar to that of Newtonian fluids. The activation parameters of the viscous flow regime were calculated. An influence of nitroplasticizers and dibutyl phthalate on the rheology of nitrocellulose was established. The influence of plasticizers on the mechanical properties of nitrocellulose films was discussed.

Синтезированы шесть потенциально мезогенных каламитных трициклических соединений, которые в качестве одного из терминальных заместителей содержат (S)-2-метил-1-бутилокси-хиральный фрагмент. Строение полученных веществ установлено методами элементного анализа, спектроскопии ЯМР Н и С, масс-спектрометрии. Методом DFT B3LYP оптимизированы структуры соединений, рассчитаны дипольные моменты и поляризуемость. Методом дифференциально-сканирующей калориметрии определены температуры и энтальпии фазовых переходов. Обсуждается влияние строения соединений на их мезоморфные свойства. Ключевые слова: синтез, спектроскопия, хиральный терминальный заместитель, квантовохимические расчеты, мезофаза, хиральная нематика.

Nine derivatives of nitrophthalic acids and nitrophenols were synthesized as potential plasticizers for polymers and structurally characterized by 1 H NMR and elemental analysis. The time dependences of the weight loss for the nitro derivatives synthesized and for commercial plasticizers (dibutyl phthalate and dioctyl phthalate) were obtained by gravimetric method at 100ºC, and their volatilities and dipole moments were calculated. The resultant nitroplasticizers are considerably less volatile than dibutyl phthalate. Low volatility is associated not so much with high molecular weight as with high polarity. The nitroplasticizers are well compatible with cellulose esters and exhibit low rates of migration from polymer films.

The surface of a Chromaton N-AW diatomite adsorbent was modified with copper(II) tetra(1',7',7'-trimethylbicyclo[2.2.1]heptano-[2',3'-b]-pyrazino)porphyrazine. Adsorption of vapors of 20 organic compounds on the surface of the modified adsorbent was studied by inverse gas chromatography. Electron-donor isomers of methylpyridine and dimethylpyridine, isomers of weakly polar xylenes and cresols, aliphatic alcohols, and other hydrocarbons capable of showing various types of intermolecular interactions with the complex of camphor-substituted tetrapyrazinoporphyrazine with copper(II) were chosen as adsorbates. Specific retention volumes of adsorbates, heat and adsorption entropy, and Gibbs adsorption energy were calculated. The effects of temperature and chemical nature of the adsorbates on the thermodynamic characteristics of sorption are discussed. Factors of separation of closely-boiling hydrocarbons are calculated. It has been found experimentally that the macroheterocycle-based adsorbent shows high selectivity to closely-boiling compounds of various types, unattainable for the unmodified adsorbent.

The synthesis of the complexes of Cu, Ni, Co, Pd, Sn, Hg of 1',7',7'-trimethylbicyclo[2.2.1]heptano-[2',3'-b]-2,3-pyrazinoporphyrazine for new materials for variety of potential applications is described. Metallic complexes were synthesized by the template cyclotetramerization of dicarbonitrile with metal chlorides at temperature 140-150 ºС for 20 min. Ammonium molybdate tetrahydrate was used as a catalyst. The products were purificated by chromatography on silica gel (eluent -chloroform). Complexes of Pd, Sn and Hg were synthesized for the first time. The metallocomplexes of camphor-substituted tetrapyrazinoporphyrazine are crystalline substances of dark blue color, not fusible up to 300 ° C, which have good solubility in chloroform, toluene, ethanol, acetone, DMF, acetic and trifluoroacetic acids. The chemical structures of the complexes of Cu, Ni, Co, Pd, Sn, Hg of 1',7',7'-trimethylbicyclo[2.2.1]heptano-[2’,3’-b]-2,3-pyrazinoporphyrazine obtained in this study were characterized by proton nuclear magnetic resonance and mass spectrometry. The absence of impurity signals in the 1H NMR spectra indicates a high degree of purity of the compounds obtained. For copper, nickel and cobalt complexes, a good correlation was found between the experimental and literature data on the chemical shifts of protons in 1H NMR spectra. Optical properties of the synthesized complexes were studied. The electronic absorption spectra of the complexes in their chloroform, DMF, acetic acid and sulfuric acid solutions were obtained. In organic solvents the typical B band (Soret band, around 400 nm) and Q band (in 600-700 nm region) of phthalocyanines were identified in this study. Complexes of Pd, Sn and Hg in their sulfuric acid solutions are non-stable. The influence of the chemical structure of metalic complexes and solvents on the optical properties was studied. Emission properties of the synthesized complexes of Pd and Hg in their chloroform and DMF solutions were analyzed. Hg-porphyrazine has very intensive fluorescence. The solution has blue color and red fluorescence at common condition.Forcitation:Kuvshinov G.V., Ziyadova T.M., Kuvshinova S.A., Koifman O.I. Synthesis and optical properties of camphor-sabstituted tetrapyrazinoporphyrazines. Izv. Vyssh. Uchebn. Zaved. Khim. Khim. Tekhnol. 2017. V. 60. N 4. P. 60-67.

The synthesis of the chiral 4-[(S)-2-methyl-3-hydroxypropyloxy]-4'-formylazobenzene (S-MHPFAB), 4[(S)-2-methyl-3-hydroxypropyloxy]-4'-cyanoazoxybenzene (S-MHPCAOB) and 4-[(S)-2-methyl-3hydroxypropyloxy]-4'-cyanobiphenyl (S-MHPCB) is described. The chemical structures of compounds obtained were characterized by elemental analysis and proton nuclear magnetic resonance spectrometry. The mesomorphic properties have been investigated by polarizing optical microscopy. It is found that the formylazobenzene and cyanoazoxybenzene containing chiral terminal substituent with hydroxyl group possessed no liquid crystalline properties. Cyanobiphenyl S-MHPCB formed a nematic phase on cooling. Optically active cyanobiphenyl S-MHPCB induced a chiral nematic phase in the mesophase of the supramolecular liquid crystalline 4-(3-hydroxypropyloxy)-4'-cyanobiphenyl with a characteristic "finger print" texture and large value of the pitch of the cholesteric structure. The dielectric constant as a function of temperature has been determined via dielcometry measurements, and the dielectric anisotropy of the studied cyanobiphenyl S-MHPCB and system 4-(3-hydroxypropyloxy)-4'-cyanobiphenyl (90 %) - S-MHPCB (10 %) were revealed. It was found that the cyanobiphenyl S-MHPCB exhibited a small negative dielectric anisotropy and the studied mixture exhibited a small positive dielectric anisotropy. The effects of the molecule structure on the mesomorphic and dielectric properties of compounds obtained and their mixtures have been studied and discussed.

Mesomorphic properties of the 4-(4-{4-[2-hydroxyethyloxy] benzoyloxy}-phenyldiazenyl) benzaldehyde (HEOPhOB) have been investigated by differential scanning calorimetry. The studied HEOPhOB have revealed enantiotropic nematic mesomorphism over wide temperature range. The sorption from the gaseous phase of eight organic compounds by HEOPhOB has been studied by gas chromatography. Strong polar electron-donating isomers of methylpyridines and dimethylpyridines as well as low-polar isomers of xylenes and cresols were used as sorbates. Specific retention volume and separation parameters of the sorbates were calculated. Sorption and selective properties of the stationary phase based on HEOPhOB were analyzed. Gas chromatography studies have shown that sorbents based on HEOPhOB are highly selective towards various structural isomers; that cannot be achieved using conventional nematic liquid crystals.

Adsorption of 16 organic compounds from the gas phase by 4-{4-[4(S)-2-methyl-1-butoxybenzoyloxy]phenyldiazenyl}benzaldehyde was studied by gas chromatography. It was shown by means of differential scanning calorimetry that 4-{4-[4(S)-2-methyl-1-butoxybenzoyloxy]phenyldiazenyl]benzaldehyde is an enantiotropic polymorphic mesogen and forms smectic and nematic liquid crystal phases. Electron-donor isomers of methylpyridine and dimethylpyridine, isomers of weakly polar xylenes and cresols, and enantiomers of 2,3-butanediol and terpene hydrocarbons, capable of various types of intermolecular interactions with mesogenic aldehyde, were selected as adsorbates. Specific retention volumes of adsorbates and criteria for their separation were calculated. The effect of temperature and chemical nature of the adsorbates on their adsorption redistribution in the gas–liquid crystal system is discussed. It was found experimentally that the adsorbent based on 4-{4-[4(S)-2-methyl-1-butoxybenzoyloxy]phenyldiazeny}lbenzaldehyde exhibits high selectivity for close-boiling organic compounds of various nature and good efficiency and productivity in their separation.

Smectic phase of formyl derivatives of azobenzene has been identified by means of polarization thermomicroscopy using a miscibility criterion. The study of dielectric properties and simulation of dipole moments and Kirkwood correlation factors have revealed that azobenzene and biphenyl derivatives containing hydroxy end group in the aliphatic terminal substituent can form supramolecules and linear associates stabilized by hydrogen bonds. The sorbents based on the studied liquid crystals have exhibited high structural selectivity with respect to isomers of various organic compounds. Thermodynamic manifestations of the specific mesogen–non-mesomorphic sorbate interactions have been revealed.