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New organo-mineral composites SiO2/poly(styrene-b-4-vinylpyridine) were obtained by adsorption of block- copolymers poly(styrene-b-4-vinylpyridine) with molar ratios of styrene (St) and 4-vinylpyridie (4-VP) St:4-VP = 1:4 and St:4-VP = 1:5 from THF solution onto silica gel surface. Block-copolymers were synthesized by controlled radical polymerization of styrene with RAFT agent and further copolymerization with 4-vinylpyridine. Also blok-copolymer with thiol end-group was obtained and has been employed for preparation of the composite. Composition of the block-copolymers and surface morphology of composites obtained were determined using 1H NMR and FT-IR spectroscopy, differential scanning calorimetry, thermogravimetric analysis and scanning electron microscopy. It was established that sorption capacity of the organo-mineral composites toward Pb(ІІ), Fe(ІІІ) and Cu(ІІ) ions is in 2–4 times higher in comparison with parent silica gel. [ABSTRACT FROM AUTHOR]

A number of new organo-mineral composites in different mass ratios of organic and inorganic components were obtained by adsorption on the silica gel surface of 4-vinylpyridine–styrene copolymer. The fact of the copolymer immobilization on the silica gel surface was confirmed by Fourier transform infrared spectroscopy (FTIR) spectroscopy and thermogravimetry combined with mass-spectrometry analysis. Thermogravimetric analysis was employed for estimation of copolymers mass content in the composite obtained. It has been established that all the synthesized composites exhibit sorption activity toward traces of Cu (II), Pb (II) and Fe (III) ions in neutral aqueous medium. [ABSTRACT FROM AUTHOR]

A new mineral-organic composite by in situ immobilization of poly(4-vinylpyridine-co-styrene-co-maleic anhydride) on the silica gel surface was synthesized. According to TG-analysis, the composite contained 31.84 wt.% of immobilized copolymer. The highest sorption activity of a new composite was established towards micro-quantities of Cu (II) ions in neutral medium as well as towards Pb(II) and Fe(III) ions in a slightly acidic medium with the background of phthalate buffer and no sorption activity towards Cd(II) ions. The composite obtained exhibits a sorption capacity higher in 1.88, 5.00 and 3.35 times for Fe(III), Cu(II) and Pb(II) ions respectively in comparison with parent silica gel. [ABSTRACT FROM AUTHOR]

As the step to design nanosystems for X-ray excited sensitizing of singlet oxygen, nanoparticles of polystyrene and polystyrene with encapsulated 2,5-diphenyloxazole were synthesized. Binding of the photosensitizer chlorin e6molecules to both kinds of nanoparticles was shown. Excitation energy transfer from styrene chromophores of polystyrene to the bound chlorin e6molecules occurs in the case of both kinds of nanoparticles. Efficiency of the energy transfer in 2,5-diphenyloxazole-mediated case is higher (0.17) as compared to the non-mediated one (0.12). [ABSTRACT FROM AUTHOR]

Phenylene-containing monomer1possessingO-methacryloyl and styrene double bonds with different reactivities in radical polymerization was designed as new type of bifunctional monomers suitable for preparation of LC photoaligning alkene-functionalized polymers. To elucidate an individual contribution of double bond of each type into kinetics of bifunctional monomers polymerization, thermo- and photo-induced polymerization of model monomers were investigated and compared. Polymer poly-1obtained by thermo-induced radical polymerization demonstrated high efficiency of LC ZLI 2293 photoalignment. [ABSTRACT FROM PUBLISHER]

Grid algorithms developed for parallel code RADUGA-5.1(P) to calculate by discrete ordinate method radiation fields from sources, localized in 3-D spatial regions, are outlined. Computation results confirming high calculation accuracy guaranteed by the algorithms are presented. [ABSTRACT FROM AUTHOR]

Rheological and mechanical properties of mixtures and films of two cellulose ethers (methylcellulose [MC] and hydroxyethylcellulose [HEC]) with polyacrylic acid (PAAc) were studied using viscometry and shear rheology, optical density measurements, and tensile testing measurements. The rheological behavior of PAAc-MC mixtures in dilute solutions was similar to that of PAAc-HEC; however, in semidilute solutions of their mixtures, differences were observed. The MC-PAAc films prepared from the mixtures showed a change of mechanical properties due to the formation of an interpolymer complex. [ABSTRACT FROM AUTHOR]