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Vol 468, No 2 (2016)
- Year: 2016
- Articles: 9
- URL: https://journals.rcsi.science/0012-5008/issue/view/9221
Chemistry
Copolymers of N-vinyl-2-pyrrolidone and condensation polymers
Abstract
The results of study on the radical polymerization of N-vinyl-2-pyrrolidone containing a dissolved polyimide, an aromatic polyamide, and a polyarylate are presented. Formation of both poly(vinylpyrrolidone) homopolymer and its copolymers with the above condensation polymers is detected. The obtained (co)polymers differ from poly(vinylpyrrolidone) in heat resistance and solubility. It was shown that polyimides can be prepared in a N-vinyl-2-pyrrolidone medium followed by in situ polymerization of the latter.
169-173
Polyphenol derivatives of porphyrins containing fluorene units: Synthesis and positive-tone photoresists for 22-nanometer lithography
Abstract
A new strategy was proposed for the synthesis of polyphenol derivatives of fluorene-containing porphyrins to be used as the base for positive-tone photoresists for lithography with exposure at 13.5 nm wavelength, which allow fabrication of microchips with a size of down to 22 nm. Polyphenols based on fluorenecontaining porphyrins were synthesized for the first time. It was shown that these polyphenol derivatives can be used to obtain positive-tone photoresists with a resolution of 22 nm.
174-178
A new route to MFI/MCM-41 micro-mesoporous composite
Abstract
A new route to MFI/MCM-41 micro-mesoporous composite is reported. This composite was synthesized for the first time by the hydrothermal microwave two-template method, and the stage of crystallization was carried out for the first time at 190°C. The developed procedure makes it possible to significantly reduce the time of synthesis of the MFI/MCM-41 micro-mesoporous composite as compared with the known methods.
179-182
Nanocomposite forming on the cathode in electrochemical reduction of copper ions from a polymer solution
Abstract
Copper electrodeposition from a solution of a mixture of copper(II) sulfate and poly(N-vinylpyrrolidone) is accompanied by the formation of a nanocomposite on the cathode. The nanocomposite contains copper nanoparticles and up to 20 wt % polymer. The composite forms by a noncovalent interaction of polymer macromolecules with the surface of copper particles growing on the cathode.
183-186
Composite materials based on fluoropolymers and oxyfluoride glasses
Abstract
It was shown that molded specimens of polymer composite materials can be obtained by an extrusion method by melt blending of Fluoroplast F-2 MB (modified poly(vinylidene difluoride)) and oxyfluoride glasses of the composition 3B2O3 (40SnF2–30SnO–30P2O5). The compositions of the observed phases of the composites were determined. Conclusions were made on the incompatibility of the components, their dispersion distribution, and strong adhesion interaction. Data on the nano level of the blending of the components were obtained. The elongation and Brinell hardness were measured in the composites with various (0–50 vol %) oxyfluoride contents. It was concluded that it is possible to produce composites based on fluorinated hydrocarbon and fluoroxide polymers.
187-190
Synthesis and structure of 5,7-Di(tert-butyl)-2-(8-methanesulfonyloxyquinolin-2-yl)-1,3-tropolone
Abstract
5,7-Di(tert-butyl)-2-(8-methanesulfonyloxyquinolin-2-yl)-1,3-tropolone whose structure was established by X-ray diffraction analysis and confirmed by 1H and 13C NMR, IR spectroscopy, and mass spectrometry, was obtained by the reaction of 2-methyl-8-methanesulfonyloxyquinoline with 3,5-di(tert-butyl)-1,2-benzoquinone. According to X-ray diffraction study, this sulfonyloxyquinolinotropolone exists in the NH tautomeric form with methanesulfonyloxy group in the exo position to the tropolone ring and the sixmembered chelate ring produced by the quinoline and tropolone moieties stabilized by strong intramolecular hydrogen bond. The strong intramolecular hydrogen bond between the phenolic oxygen atom and the six-membered chelate ring provides supplementary contribution to the stabilization of the NH tautomeric form.
191-194
Effect of the clathrate hydrate environment on the structure of collagen xenograft tissue with chitosan coating deposited from solution in the H2O/CO2 system at high pressure
Abstract
The effect of the clathrate hydrate environment in the water/carbon dioxide system on the structure of the chitosan-coated collagen xenograft tissue was demonstrated. The collagen xenograft tissue treated in this environment is a porous material with a pore size of 50–500 nm having also micrometer size (1–3 μm) pores. The high porosity results in averaging of the structural organization features in xenograft tissues with different orientation of collagen fibrils. Treatment of xenograft tissues in the H2O/CO2 environment in the presence of clathrate hydrates allows the manufacture of a nanoporous biodegradable material suitable for biomedical applications.
195-198
Chemical Technology
Bone cements in the calcium phosphate–chitosan systems containing magnesium and zinc
Abstract
Based on studying the possibility of the introduction of physiologically important cations into a cementing system, technology of fabrication of highly deformable calcium phosphate cements has been developed for bone tissue reconstruction in medicine. It has been elucidated that the method of introduction of metal cations (magnesium, zinc) into the cementing system has an effect on the formation of the microstructure and properties. The in vitro degradation of composite cements in simulated body fluids has been studied. Results have been obtained for the development of cements with tailored properties, which can be varied in different ranges.
199-201
New electron-accepting quinoxalinothiadiazole-containing heterocycles as promising building blocks for organic optoelectronic devices
Abstract
Two novel quinoxalinothiadiazole-containing dibromides—4,9-dibromo-6,7-bis(9,9-didodecyl7-fluoro-9H-fluoren-2-yl)[1,2,5]thiadiazolo[3,4-g]quinoxaline (11) and 4,9-dibromo-6,7-bis(9,9-didodecyl-5,7-difluoro-9H-fluoren-2-yl)[1,2,5]thiadiazolo[3,4-g]quinoxaline (19)—have been synthesized, which are promising strong electron-accepting building blocks for preparing highly efficient narrow-bandgap D–A conjugated polymers. The composition and structure of monomers 11 and 19 have been proved by elemental analysis data, IR spectroscopy, and 1H and 13C NMR.
202-207