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Shchegolikhina O.I.,RAS Nesmeyanov Institute of Organoelement Compounds | Matukhina E.V.,Moscow State Pedagogical University | Anisimov A.A.,RAS Nesmeyanov Institute of Organoelement Compounds | Molodtsova Y.A.,RAS Nesmeyanov Institute of Organoelement Compounds | And 3 more authors.
Macroheterocycles | Year: 2016

The samples of tris-cis-tris-trans-dodecaphenylcyclododecasiloxanedodecaol (dodecaol) with different crystalline structure have been investigated by means of TGA and X-ray methods. The samples obtained have exhibited mesomor phic properties, the thermal behavior and the type of mesomorphic ordering being directly associated with the type of the main H-bonded unit forming the initial crystalline structure. In turn, the type of an ordering in the mesophase has determined the structure of the final products of polycondensation. It was shown that the multifunctional tris-cis-tristrans- dodecaphenylcyclododecasiloxanedodecaol can be used as possible monomer precursor for the covalent-bonded “double-chain sheet polymer”. © ISUCT Publishing.


Lesnyakova L.V.,Ns Enikolopov Institute Of Synthetic Polymeric Materials | Chernyshenko A.O.,Ns Enikolopov Institute Of Synthetic Polymeric Materials | Akopova T.A.,Ns Enikolopov Institute Of Synthetic Polymeric Materials | Vladimirov L.V.,Ns Enikolopov Institute Of Synthetic Polymeric Materials | And 3 more authors.
International Polymer Science and Technology | Year: 2013

By exposure to shear strains in solid phase, polyvinyl alcohol was obtained from polyvinyl acetate. The reaction mixture of solid NaOH and polyvinyl acetate was subjected to the combined action of pressure and shear strains in an extruder. The obtained products were characterised by their composition, solubility, molecular weight, and thermal properties. The influence of the amount of NaOH introduced and the use of a less alkaline reagent on the composition of the obtained products was investigated. © 2013 Smithers Rapra Technology.


Cherkasova A.V.,RAS Semenov Institute of Chemical Physics | Glagolev N.N.,RAS Semenov Institute of Chemical Physics | Shienok A.I.,RAS Semenov Institute of Chemical Physics | Demina T.S.,Ns Enikolopov Institute Of Synthetic Polymeric Materials | And 6 more authors.
Journal of Materials Science: Materials in Medicine | Year: 2016

The presented paper is focused on impregnation of chitosan and its derivatives with a biologically active triaryl imidazole model compound ((2-2-hydroxyphenyl)-4.5-diphenyl-1H-imidazole) in the supercritical carbon dioxide medium. Since initial chitosan represents a polycation-exchange resin and does not swell in supercritical carbon dioxide, the impregnation was carried out in the presence of water (0.15–3.0 vol%). The maximum 2-2-hydroxyphenyl)-4.5-diphenyl-1H-imidazole concentration in a chitosan film was achieved at the ~5 × 10−3 g/cm3 water content in the reactor. We also used hydroxy carboxylic acid derivatives of chitosan and its copolymer with polylactide as matrices for introduction of hydrophobic 2-2-hydroxyphenyl)-4.5-diphenyl-1H-imidazole. We have shown that unmodified chitosan contains the greatest amount of 2-2-hydroxyphenyl)-4.5-diphenyl-1H-imidazole, as compared with its hydrophobic derivatives. The kinetics of 2-2-hydroxyphenyl)-4.5-diphenyl-1H-imidazole diffusion from a chitosan matrix was studied in acidified water with pH 1.6. We found that the complete release of 2-2-hydroxyphenyl)-4.5-diphenyl-1H-imidazole into the aqueous phase from unmodified chitosan films occurred in 48 h, while its complete release from chitosan modified with hydroxy carboxylic acids occurred in 5 min or less. © 2016, Springer Science+Business Media New York.


PubMed | Ns Enikolopov Institute Of Synthetic Polymeric Materials, Institute of Photonic Technologies and RAS Semenov Institute of Chemical Physics
Type: Journal Article | Journal: Journal of materials science. Materials in medicine | Year: 2016

The presented paper is focused on impregnation of chitosan and its derivatives with a biologically active triaryl imidazole model compound ((2-2-hydroxyphenyl)-4.5-diphenyl-1H-imidazole) in the supercritical carbon dioxide medium. Since initial chitosan represents a polycation-exchange resin and does not swell in supercritical carbon dioxide, the impregnation was carried out in the presence of water (0.15-3.0 vol%). The maximum 2-2-hydroxyphenyl)-4.5-diphenyl-1H-imidazole concentration in a chitosan film was achieved at the ~510(-3)g/cm(3) water content in the reactor. We also used hydroxy carboxylic acid derivatives of chitosan and its copolymer with polylactide as matrices for introduction of hydrophobic 2-2-hydroxyphenyl)-4.5-diphenyl-1H-imidazole. We have shown that unmodified chitosan contains the greatest amount of 2-2-hydroxyphenyl)-4.5-diphenyl-1H-imidazole, as compared with its hydrophobic derivatives. The kinetics of 2-2-hydroxyphenyl)-4.5-diphenyl-1H-imidazole diffusion from a chitosan matrix was studied in acidified water with pH 1.6. We found that the complete release of 2-2-hydroxyphenyl)-4.5-diphenyl-1H-imidazole into the aqueous phase from unmodified chitosan films occurred in 48h, while its complete release from chitosan modified with hydroxy carboxylic acids occurred in 5min or less.

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