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Copyright of Polimery is the property of Industrial Chemistry Research Institute and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Polimery is the property of Industrial Chemistry Research Institute and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Polimery is the property of Industrial Chemistry Research Institute and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Polimery is the property of Industrial Chemistry Research Institute and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Polimery is the property of Industrial Chemistry Research Institute and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Polimery is the property of Industrial Chemistry Research Institute and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract: New quaternary ammonium salts containing unsaturated substituents (allyl or vinyl) were synthesized. All of them were subjected to spectroscopic, elemental and thermogravimetric analyses. The above compounds are ionic liquids (T m <100°C) and were applied to immobilization of three rhodium(I) complexes [Rh(PPh3)3Cl], [{Rh(μ-Cl)(cod)}2] and [{Rh(μ-OSiMe3)(cod)}2] as well as three platinum complexes at different oxidation states [Pt(PPh3)4], K2[PtCl4] and K2[PtCl6]. Homogeneous catalytic systems were obtained and employed in the biphasic process of hydrosilylation of octene and allyl glycidyl ether with 1,1,1,3,5,5,5-heptamethyltrisiloxane. Catalytic activities of all the systems were compared and the best one was selected. The latter made it possible to recycle 10 times the same catalyst sample without a decrease in its activity and to easy separate the catalyst from the post-reaction mixture by decantation. The developed system is one of the most effective catalytic systems for hydrosilylation known to date. [Copyright &y& Elsevier]

Epoxy functional (poly)siloxanes are one of the most important classes of modified silicones. Due to high reactivity of epoxy group and specific features of siloxane chain, they can make an excellent raw material for synthesis of hybrid materials. Results obtained in this study have shown that both the modification of epoxy resins with epoxy functional disiloxanes as well as the application of polysiloxanes with long polysiloxane chains and a specified content of epoxy groups makes it possible to produce hybrid materials of very good thermal stability. Crosslinking reactions were carried out with use of four diamines of which the best one appeared to be 4,4′-diaminodiphenylmethane. The highest thermal stability was found in the case of hybrid materials obtained from epoxy functional polysiloxanes. [ABSTRACT FROM AUTHOR]

Copyright of Polimery is the property of Industrial Chemistry Research Institute and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Polimery is the property of Industrial Chemistry Research Institute and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Polimery is the property of Industrial Chemistry Research Institute and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Hepta(isobuthyl)ethyltriethoxysilyloctasilsesquioxane was synthesized by hydrosilylation of hepta(isobuthyl)vinyloctasilsesquioxane with triethoxysilane, over Karstedt catalyst and tetrahydrofuran. Hybrid systems of silica and monofunctional silsesquioxane (SiO2/POSS) were obtained by solvent evaporation, using emulsion silica (ES) and hydrated silica (HS), obtained by precipitation in emulsion or water media. For their surface modification hepta(isobuthyl)ethyltriethoxysilyloctasilsesquioxane was used. The hybrids were characterized by dispersion analysis (NIBS method and laser diffraction technique) and morphological analysis (transmission electron microscopy) as well as wettability profiles in an aqueous system. The adsorptive properties of the hybrids were evaluated on the basis of surface area BET, pore volume and size. The effectiveness of modification of the hybrid fillers was tested by FTIR and 29Si CP MAS NMR. [ABSTRACT FROM AUTHOR]

Abstract: A typical composition consisting of a low-molecular commercial epoxy resin based on bisphenol A and aliphatic polyamine hardener: triethylenetetramine was modified by replacing a part of the composition with up to 15 wt.% of low molecular weight bis(glycidylpropyl)- or bis(aminopropyl)-tetramethyldisiloxane. The reactivity of the compositions and basic properties of the resulting epoxy polymers, including glass transition temperature, storage modulus, thermal stability, impact and bending strengths, Brinell hardness, and flammability (limiting oxygen index) were evaluated. [Copyright &y& Elsevier]

Azido functional silsesquioxanes are the natural exten-sion of click chemistry and a convenient starting material for further synthesis of new POSS compounds as well as modification of other materials in 1,3-dipolar cycloaddition processes. Increasing de-mand for these compounds has stimulated the search for new and ef-ficient methods for their synthesis. In this paper, we present characterization and methodology of synthesis of new POSS com-pounds bearing azido groups via epoxy ring-opening reaction in ep-oxy functional POSS compounds with sodium azide. Two new POSS derivatives with azido and hydroxy functionalities were obtained with a high selectivity and yield. Also two new nitro- and hydroxy-functionalized POSS derivatives were obtained in the re-action of epoxy-functionalized POSS compounds with 4-nitrophe-nol. [ABSTRACT FROM AUTHOR]

Abstract: Silicone waxes, i.e. polysiloxanes with a long alkyl chain (>C8) as a pendant group make one of the most important classes of modified polysiloxanes widely applied to many branches of industry. Main methods of synthesis of silicone waxes are based on catalytic processes of hydrosilylation of alkenes with poly(hydro, methyl)siloxanes. Results of studies on syntheses of silicone waxes in homo- and heterogeneous catalytic systems are presented. The most effective catalyst for the reactions studied appeared to be siloxide rhodium complex [{Rh(μ-OSiMe3)(cod)}2]. The immobilisation of this complex in ionic liquids resulted in a highly selective and very active catalytic biphase system that enabled easy product separation and repeated use of the catalytic system. Excellent selectivity was observed also in the case of hydrosilylation of the above alkenes in a typical heterogeneous system in the presence of supported metallic catalysts. In this group of catalysts particularly active was platinum supported on a highly hydrophobic styrene–divinylbenzene resin which enabled to obtain product yield of about 90% in reactions with 1-octene and well over 90% in reactions with 1-hexadecene. When platinum was accompanied by copper on supports such as activated carbon and carbon black, product yields were clearly higher than those obtained on monometallic catalysts. Supported rhodium was either inactive or poorly active in reactions studied. [Copyright &y& Elsevier]

Abstract: Nickel(0) complexes 1–4 containing π-coordinated olefin and triphenylphosphine (tricyclohexylphosphine) (starting from Ni(cod)2) were prepared and the X-ray structures of 1 and 2 were resolved. The complexes appeared as efficient catalysts in dehydrogenative silylation of styrene and vinyltris(trimethylsiloxy)silane, but only after prior oxygenation of phosphine ligand. Stoichiometric studies of Ni(0) complexes with substrates showed that the bis(silyl)nickel(II) complex was a key intermediate in both reactions examined. A scheme of catalysis by Ni(0) complex involving olefin insertion into Ni–Si bond, as a crucial step, is presented. [Copyright &y& Elsevier]

The hydrosilylation of 1-heptene, allyl glycidyl ether and, allyl polyether by heptamethylhydrotrisiloxane and poly(hydro, methyl)(dimethyl)siloxane catalyzed by rhodium(I) complexes (particularly [{Rh(μ–OSi Me3)( cod)}2]) in imidazolium ionic liquids (especially [Tri MIM] MeSO4) gives heptyl and glycidyloxy functional (poly)siloxanes and silicone polyethers with high yield and selectivity. The catalytic system based on rhodium siloxide can be easily separated from the product and successfully reused up to five times. [ABSTRACT FROM AUTHOR]

Abstract: Catalytic reactivity of Si–H bond of di-, trisiloxanes with allyl chloride in the presence of platinum catalyst has been examined. Hydrosilylation process competes with hydrogen substitution by chlorine and/or propenyl group. The effect of the reaction conditions as well as structure of siloxane on the yield and selectivity of the number of products has been discussed. Several consecutive-competitive processes have been identified. The results obtained can be helpful in the study of the catalytic hydropolysiloxanes reactions with allyl derivatives–systems of great practical importance, to produce commercial functionalized silicones. [Copyright &y& Elsevier]

Copyright of Polimery is the property of Industrial Chemistry Research Institute and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Trisubstituted silanes, HSiRX (R = Me or Et, X = Cl, OEt, or Ph; n = 0-3) oxidatively add to the complex [RhCl(cod)(1-hexene)] (cod = cycloocta-1,5-diene) to yield [RhCl(cod)(1-hexene)(H)(SiR)] [( 1)]. Subsequent steps of hydrosilylation follow, i.e. cis-insertion of the alkene ( π-σ rearrangement) and then reductive elimination of the product, according to the general Chalk and Harrod scheme. A quantitative correlation between the second order rate constant, k, of the oxidative addition (followed spectrophotometrically) at 20°C in benzene solution and the structure of the trisubstituted silane represented by Stereoelectronic parameters χ,θ and E′' for the SiRX groups was established. The maximal hydrosilylation rate followed by g.l.c., is strongly retarded by highly electronegative substituents X on silicon and results from the elimination rate of the hydrosilylation product from ( 1) and the maximal concentration of ( 1) in solution. [ABSTRACT FROM AUTHOR]

The structural characterization of glass slides surface-modified with 3-azidopropyltrimethoxysilane and used for anchoring nucleic acids, resulting in the so-called DNA microarrays, is presented. Depending on the silanization conditions, the slides were found to show different oligonucleotide binding efficiency, thus, an attempt was made to correlate this efficiency with the structural characteristics of the silane layers. Atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS) and X-ray reflectometry (XRR) measurements provided information on the surface topography, chemical composition and thickness of the silane films, respectively. The surface for which the best oligonucleotides binding efficiency is observed, has been found to consist of a densely-packed silane layer, decorated with a high-number of additional clusters that are believed to host exposed azide groups. [ABSTRACT FROM AUTHOR]

The development of novel flame retardants for cotton textiles that form a stable layer on textile fiber is of high economical and practical relevance. A novel flame retardant fluorinated phosphoric acid esters modified silicone resins for cotton modification were synthesized. The investigated phosphoric acid esters based compounds were substituted by a fluorinated chain or ring, and alkoxysilyl groups. The presence of alkoxysilyl groups allowed the formation of bonds with cellulose, while derivatives of phosphoric esters reduced the flammability of fabrics. Additionally, the presence of fluoride in their structures affected the hydrophobic properties. Cotton fabrics were modified in a simple one-step process by dip-coating method. The flame retardant properties of modified textiles were examined by performing microcalorimetric analysis, thermogravimetry analysis, and measuring oxygen index. The hydrophobicity was evaluated by measuring the water contact angle. The modified fabrics were characterized by SEM-EDS (Scanning Electron Microscopy with Energy Dispersive Spectroscopy) analysis and surface morphology. As a result of the tests, multifunctional fabrics were obtained. [ABSTRACT FROM AUTHOR]