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Selective mono-functionalization of 1,1,3,3-tetramethyldisiloxane (TMDSO) with olefins via hydrosilylation reaction is reported. On the basis of a study of platinum- and rhodium complexes in the reactions between TMDSO and selected olefins containing C=C bond, it was possible to choose the most efficient catalyst whose application in the solvent-free system led to selective mono-functionalization of the disiloxane reagent and simultaneous formation of only β -regioisomeric products, bearing in their structure functional groups of unique reactivity or physicochemical properties. [ABSTRACT FROM AUTHOR]

In this work, a series of high-solids crosslinked hybrid networks based on the epoxy-terminated urethane oligomer and the comb-like structure epoxy-functional siloxane cured with diethylenetriamine, were obtained. The structure of the obtained poly(urethane-siloxane) thermosets was confirmed by FTIR spectroscopy. The samples were submitted to detailed thermal degradation investigations at non-isothermal conditions in nitrogen and air. The contact angles of the coatings and free surface energy calculated by Owens-Wend as well as van Oss-Good method, were studied. Some coating properties of the obtained hybrid materials were also investigated. The synthesized poly(urethane-siloxane) networks are hydrophobic materials, with free surface energy of 26-29 mJ/m. The thermal stability and hardness of these increases with increasing siloxane content. [ABSTRACT FROM AUTHOR]

The reactivity of a system comprising commercial epoxy resin Epidian 6 (E6) and triethylenetetramine (Z-1) hardener was studied. The system was modified with two low-molecular siloxane modifiers: 1,3-bis(glycidyloxypropyl)-1,1,3,3-tetramethyldisiloxane (DS1) and 1,3-bis(aminopropyl)-1,1,3,3-tetramethyldisiloxane (DS2). The modifiers replaced 10 mass% of E6 or Z-1, respectively. The systems E6/DS2 and DS1/Z-1 were also studied. Enthalpy of curing was determined for all systems in isothermal conditions and dynamically, i.e., in the range of 0-250 °C with linearly increasing temperature at the rate of 2, 5, 10, and 20 °C min. The activation energy of curing was determined using isoconversional methods by Friedman and Kissinger-Akahira-Sunose. The epoxy systems containing siloxane modifiers had generally lower activation energies than the reference E6/Z-1 system. The time to gelation measurements were taken using the temperature-modulated differential scanning calorimetry. [ABSTRACT FROM AUTHOR]

In this work series of novel high-solids crosslinked hybrid networks based on the epoxy-terminated polyurethane prepolymer and the comb-like structure co-poly(dimethyl)(methyl, 3-glycidoxypropyl)siloxane cured with diethylenetriamine, were obtained. The viscosity lowering of epoxy-terminated polyurethane prepolymer with temperature allowed for the preparation of the hybrid systems without using of any solvent. The structure of the obtained poly(urethane–siloxane) thermosets was confirmed by FT-IR spectroscopy. The DSC studies reveal, that the addition of siloxane resulted in the decrease of the glass transition temperature of the hybrid materials. The synthesized poly(urethane–siloxane) networks are hydrophobic, with the free surface energy of 17–31 mJ/m 2 . An increased amount of siloxane resulted in an increase of water contact angle and decrease of degree of water absorption as well as of FSE, which confirms a hydrophobic nature of the employed siloxane. Some properties of obtained hybrid materials based coatings were also studied. [ABSTRACT FROM AUTHOR]

A series of crosslinked hybrid poly(urethane-siloxane) networks based on comb-like structure co-poly(dimethyl)(methyl, hydroxypolyoxyethylenepropyl) siloxane cured with aliphatic diicocyanates hexamethylene diisocyanate (HDI), isophorone diisocyanate (IPDI), and 4,4'-methylenebis(cyclohexyl isocyanate) (H12MDI), were obtained. The samples have been submitted to thermal stability investigations at non-isothermal conditions in nitrogen and air. The thermal degradation behavior was investigated by evolved gas analysis, using coupled TG-FTIR technique. The kinetic parameters of the degradation process were determined both by isoconversional methods of Friedman and Ozawa-Flynn-Wall as well as by model fitting multivariate non-linear regression method. It was observed that the thermal stability of the poly(urethane-siloxane) thermosets depends on employed diisocyanate. The best fit of the f(a) function with the experimental data was found for two-step degradation mechanism. Successive stages of thermal decomposition occurred by diffusion and by the expanded Prout-Tompkins model, respectively. [ABSTRACT FROM AUTHOR]

The effectiveness of protective coatings based on 3-(2,2,3,3,4,4,5,5-octafluoropentyloxy)propyltriethoxysilane (OFTES) in protecting concrete surfaces against water was tested. For the synthesis of OFTES, 2,2,3,3,4,4,5,5-octafluoropentanol, which is a by-product in the synthesis of poly(tetrafluoroethylene), was used. The proposed silane is a cheaper alternative to the fluorinated organosilicon compounds currently used. The coatings were deposited by the sol-gel method. As a result of the creation of chemical bonds between the concrete surface and the silane, a coating was created that permanently increases the hydrophobicity of the concrete. Fluorine chains attached to silicon atoms are an effective barrier that prevents access to water and limits its impact on the concrete surface. As a result of the proposed silanization, the concrete surface obtained a hydrophobic character at contact angles of up to 126°, and the water absorption of the concrete decreased by up to 96%. [ABSTRACT FROM AUTHOR]

Highlights: [•] The thermal decomposition of the polyurethane-siloxane semi-IPNs was investigated. [•] The thermal degradation kinetic parameters were determined. [•] The possible degradation model f(α) was proposed. [Copyright &y& Elsevier]

Reaction of the Cramer''s complex [{Rh(C2H4)2(μ-Cl)}2] with the appropriate vinylsilane molecules yields, by displacement of the ethylene ligands, the complexes [{Rh(η2-CH2&z.dbnd6;CHSiR3)2(μ-Cl)}2] (where R3=Me3 (1), Me2Ph (2), MePh2 (3), Ph3 (4), Me2(OSiMe3) (5)). The structures of 1, 2 and 3 complexes have been determined crystalographically. There are the first crystal structures of dinuclear rhodium(I) complexes with monovinylsilanes. All complexes have been characterised by multinuclear NMR spectroscopy. [Copyright &y& Elsevier]

• The alkoxysilyl derivatives of polybutadienes were obtained by hydrothiolation. • All synthetized polymers have been successfully used for concrete impregnation. • Surface impregnation of concrete resulted in endowing it with waterproof properties. In order to extend the life of concrete, various impregnation methods are used to protect it from the damaging effects of external factors. This article proposes an easy and effective method of waterproofing concrete using functionalized polybutadienes. The effects of chemical structure of polymers as well as the type of solvent used, on the hydrophobicity of modified concrete were evaluated. The effectiveness of impregnation was assessed based on the water contact angle measurements and water sorption experiments. For the best hydrophobizing preparation, the water absorption was reduced by 94% compared to the absorption for the unmodified sample. [ABSTRACT FROM AUTHOR]

Rhodium complexes ligated by imidazolium-substituted phosphine were used as catalysts in the hydrosilylation of alkynes (1-heptyne, 1-octyne, and phenylacetylene) with 1,1,1,3,5,5,5-heptamethyltrisiloxane (HMTS) or triethylsilane (TES). In all cases, the above complexes showed higher activity and selectivity compared to their precursors ([Rh(PPh3)3Cl] and [{Rh(µ-Cl)(cod)}2]). In the reactions with aliphatic alkynes (both when HMTS and TES were used as hydrosilylating agents), β(Z) isomer was mainly formed, but, in the reaction of phenylacetylene with TES, the β(E) product was formed. The catalysts are very durable, stable in air and first and foremost insoluble in the reactants which facilitated their isolation and permitted their multiple use in subsequent catalytic runs. They make a very good alternative to the commonly used homogeneous catalysts. [ABSTRACT FROM AUTHOR]

The syntheses and full spectral (NMR, MS, and IR), thermal (DSC) and ion chromatographic characterization of two series of amine-derived ionic liquids bearing allyl substituents and having chloride or bis(trifluoromethanesulfonyl)amide anions have been presented. The analysis of the dependence of the 1H NMR chemical shift values of the selected protons on the cation and anion structure has been conducted. DSC analysis records together with ion chromatography analysis results have been presented and interpreted. Moreover, a selection of obtained chloride ionic liquids have been transformed into the corresponding chlorocobaltates and chlorozincates or used as substrates in thiol–ene click reactions to indicate their potential as precursors of catalysts or various surface modifiers. [ABSTRACT FROM AUTHOR]

Ineffectiveness of the chemicals applied so far for waterlogged wood conservation created the need to develop new more, efficient and reliable agents. As an alternative, a new method with the use of organosilicon compounds differing in chemical composition and molecular weight has been investigated. The results obtained show the potential of organosilicons as consolidants in waterlogged wood conservation able to effectively stabilise wood dimensions upon drying. The best wood stabilisers were low-molecular organosilicons enable to penetrate the cell wall as well as chemicals with functional groups capable of interacting with wood polymers and forming stabilising coatings on the cell wall surface. The best anti-shrink efficiency values were obtained for (3-Mercaptopropyl)trimethoxysilane, (3-Aminopropyl)triethoxysilane, 1,3-Bis(3-aminopropyl)-1,1,3,3-tetramethyldisiloxane, reaching 98, 91 and 91%, respectively. Most of the applied organosilicons reduced wood hygroscopicity, which limits the risk of further dimensional changes of wood exposed to a variable air moisture content and potentially reduces wood biodegradation. In the light of our studies, the proposed method of waterlogged wood conservation with organosilicons is potentially reversible in the case of siloxanes and amino-silanes as well as retreatable, which complies with the requirements of the conservation ethics. [ABSTRACT FROM AUTHOR]

A new synthetic approach and full spectral (NMR, IR, MS) and ion chromatographic characterization (IC) of nitrogen‐based ionic liquids bearing allyl‐ or ethyl‐ substituent and triflate, tosylate, methyl sulfate or methanesulfonate anion has been presented. On a sample of 16 new ionic liquids, the versatility of the anion exchange method has been proven. In the metathesis reactions that have been carried out, the halide anion was exchanged in ionic liquid with an alkyl sulfonate based anion using alkylating agents. The results obtained using ion chromatographic analysis on the newly synthesized compounds have been discussed. Also, the utilization of a gaseous methyl halide by‐product, obtained in the metathesis reaction and otherwise difficult to synthesize, has been presented. This approach ensured high atom economy of the overall process, which makes the proposed methodology sustainable and eco‐friendly. [ABSTRACT FROM AUTHOR]

• Very simple method of synthesis of new anionic platinum complexes. • Full spectroscopic and crystallographic characterization of the obtained complexes. • First application of these complexes as hydrosilylation catalysts. • Easy isolation and multiple use of the catalyst. • Very high catalytic activity even after multiple use. The reaction between ionic liquid [Cat]+Cl− (where Cat stands for 1-butyl-3-methylimidazolium, 1-butyl-2,3-dimethylimidazolium or 1-butyl-4-methylpyridinium) and the metal precursor ([PtCl 2 (cod)], PtCl 4 , K 2 [PtCl 4 ] or K 2 [PtCl 6 ]) yielded two groups of derivatives: [Cat]+[PtCl 4 ]− and [Cat]+[PtCl 6 ]−, which formally are counted among halometallate ionic liquids, however, due to their high melting points they should be classified into anionic platinum complexes rather than into ionic liquids. All the derivatives were isolated and characterized spectroscopically (NMR, ESI-MS) and crystallographic structures were determined for three derivatives: ([BMPy] 2 [PtCl 4 ], [BMIM] 2 [PtCl 6 ] and [BMMIM] 2 [PtCl 6 ]. Moreover, their melting points were measured and thermal stability was assessed. The above derivatives were employed as catalysts for hydrosilylation of olefins with diverse properties. All the studied catalysts showed high activity and their insolubility in the reaction medium made easy their isolation and multiple use in subsequent catalytic runs. The most effective catalysts did not lose their activity even after ten runs, thereby they make a very good alternative to commonly used homogeneous catalysts. Their simple synthesis and stability make them interesting both for economic and ecological reasons. [ABSTRACT FROM AUTHOR]

This study discusses the effect of 3-(1,1,2,2,3,3,4,4-octafluoropentyloxy)propyltriethoxysilane (OFTES) based coatings on the anti-corrosive properties of 304 type stainless steel, which has not been described to date. The coatings were deposited from methanol using the anhydrous deposition method and influence of the sonication on this process has also been investigated. Anti-corrosive properties of modified and unmodified steel surfaces have been characterized by electrochemical and surface analysis methods. Since silicon is an element capable of forming bonds with both organic and inorganic substrates, these features allow to combine organofunctional silanes with metal as well as steel surfaces through metal O Si covalent bonds. A fluorinated alkyl chain, which is attached to the silicon atom, forms an effective barrier against an aggressive aqueous environment. [ABSTRACT FROM AUTHOR]

The development of novel flame retardants for cotton textiles that form a stable layer on the textile fiber is of high economical and practical relevance. Hexakis(3-(triethoxysilyl)propyloxy) cyclotriphosphazene has been synthesized in this work as a novel flame retardant capable of bonding to cotton fiber surface. This is the first report on the application of hydrosilylation to synthesis of triethoxysilyl cyclophosphazene derivative. The flame retardant properties of treated cotton textiles were assessed by measuring heat release rate on a pyrolysis-combustion flow microcalorimeter and determining the limiting oxygen index, whereas the thermal stability was studied by thermogravimetry. The modified fabrics were characterized by SEM-EDS analysis and surface morphology. The influence of the preparation methodology of the coating on the flame retardant performance and thermal stability are discussed. [ABSTRACT FROM AUTHOR]

The routes of synthesis, as well as, spectroscopic and X-ray diffraction characterization of a new group of bis- or hexakis-4-(dimethyl(vinyl)silyl)phenoxy and 4-(dimethylsilyl)phenoxy-substituted cyclotriphosphazenes as a versatile starting substrates for the synthesis of a variety of organic cyclophosphazene derivatives, via catalytic hydrosilylation or silylative coupling processes, is presented. [ABSTRACT FROM AUTHOR]

[Display omitted] • The synthesis of POSS derivatives containing extremely different functional groups. • The effect of the sequence of introducing substituents and their reactivity on the process of hydrosilylation. • Impact of the time of catalyst introduction on the process of hydrosilylation. • Comparison of emulsifying properties of monofunctional and bifunctional POSS compounds. • POSS with hydrophobic nature was the best emulsifying agent. The role of functionalized polyhedral oligomeric silsesquioxane (POSS) in emulsion systems is still insufficiently researched. Therefore, this paper presents two aspects. First, the effect of the sequence of olefin introduction and the olefins chemical character on the course and efficiency of hydrosilylation was studied. The use of olefins of drastically different properties was expected to maximally expose their impact on the efficiency of hydrosilylation. The second involve the application of the obtained compounds to be used as emulsifier. Functionalized silsesquioxanes were obtained by subsequent hydrosilylation of spherosilicate with two olefins that is allyl-octafluoropentyl ether and allyl polyether. The hydrosilylation process was monitored by IR spectroscopy in real time. All obtained compounds were used as emulsifiers and the stability of colloidal systems was analyzed using multiple light scattering. Moreover, emulsion stability index over time was also determined. According to the results, both the sequence and the type of introduced substituents have impact on the rate of hydrosilylation. Moreover, it has been shown that the moment of the catalyst addition also influences the character of the process. The results proved that the introduction of fluoroalkyl groups and polyether substituents significantly changed the emulsifying properties of POSS. [ABSTRACT FROM AUTHOR]

The studies were conducted on a cotton fabric modified by the mixture of tetraethoxysilane (TEOS) and triclosan (TC)—(2,4,4′-trichloro-2′-hydroxydiphenyl ether) or TEOS and quaternary ammonium salt (QAS) such as the hexadecyltrimethylammonium bromide in order to obtain biocidal (i.e. antifungal) and hydrophobic properties. The modified unwashed and washed fabrics were tested for the action of a mixture of five mould species which most often cause the decomposition of cellulose ( Chaetomium sp., Aureobasidium sp., Paecilomyces sp., Aspergillus sp., Penicillium sp.). The hydrophobicity was examined by measuring the contact angle. The fabrics modified by TC-TEOS are characterized by a higher antifungal effectiveness, however, the durability of the modification can be maintained only when they are dry-cleaned. Silanes form a silica layer on the surface of textiles which results in increased hydrophobicity. These multifunctional textiles can find applications as materials for human health, e.g. insoles, wound dressings, protective clothing, filters. [ABSTRACT FROM AUTHOR]

Chitinous scaffolds isolated from the skeleton of marine sponge Aplysina cauliformis were used as a template for the deposition of polyhedral oligomeric silsesquioxanes (POSS). These chitin–POSS based composites with hydrophobic properties were prepared for the first time using solvothermal synthesis (pH 3, temp 80 °C), and were thoroughly characterized. The resulting material was studied using scanning electron microscopy, Raman spectroscopy, X-ray photoelectron spectroscopy and thermogravimetry. A mechanism for the chitin-POSS interaction after exposure to these solvothermal conditions is proposed and discussed. [ABSTRACT FROM AUTHOR]

The properties of Langmuir monolayers and Langmuir–Blodgett as well as Langmuir–Schaefer films formed by two open-cage polyhedral oligomeric silsesquioxanes (POSS): 1,3,5,7,9,11,14-hepta-isooctyltricyclo [7.3.3.15,11] heptasiloxane-endo-3,7,14-triol (TSiO-POSS) and 1,3,5,7,9,11-octaisobutyltetracyclo [7.3.3.15,11] octasiloxane-endo-3,7-diol (DSiB-POSS) were studied. Both compounds were shown to form stable monolayers at the air/water interface. The morphology of the monolayers was visualized with a Brewster Angle Microscopy (BAM). The results obtained indicated that TSiO-POSS molecules formed dimers whereas in the case of DSiB-POSS was found the network structure, which was seen on the water/air interface as well as on L-S and L-B thin films. The difference in the interfacial behavior of POSS considered results from alkyl chains length and number of hydroxyl groups in the POSS molecule. The formation of network structure and presence of POSS dimers after transfer of the films on the solid substrates were reported. [ABSTRACT FROM AUTHOR]

Highlights: [•] Highly effective synthesis of functionalized silsesquioxane was performed. [•] Rhodium complexes immobilized on the silica surface showed the high catalytic activity. [•] Catalytic activity of the developed system is maintained after multiple use. [Copyright &y& Elsevier]

A series of ruthenium complexes (RuCl3 × 3H2O, [C5H5Ru(CH3CN)3]+[PF6]−, [RuCl2(PPh3)3], [RuHCl(CO)(PPh3)3], [RuHCl(CO)(PCy3)2]) immobilized in [bmim][Tf2N] were tested in homocoupling of vinylsilanes (H2C=CHSi(OEt)3, H2C=CHSi(Oi Pr)3, H2C=CHSi(OSiMe3)3, H2C=CHSiMe(OSiMe3)2, and H2C=CHSiPh(OSiMe3)2) performed in a biphasic system. The highest catalytic activity and selectivity of homocoupling product was observed for [RuHCl(CO)(PCy3)2]. The complex [RuHCl(CO)(PCy3)2] immobilized in a variety ionic liquids ([bmim][PF6], [bmim][BF4], [bmim][Tf2N], [bmim][TfO], [bmim][HSO4], [bmim][Cl], [trimim][MeSO4], [NBu3Me][MeSO4], [PBu4][Cl], [bpy][PF6], [bpy][BF4], [bpy][Cl]) exhibits high catalytic activity in homocoupling of H2C=CHSiMe2Ph, H2C=CHSi(OEt)3 and H2C=CHSiMe(OSiMe3)2 and enables high-yield stereoselective synthesis of the corresponding E-1,2-bis(silyl)ethenes. The immobilized complex can be easily recycled up to 12 times in the homocoupling of H2C=CHSiMe2Ph and up to 10 times in the homocoupling of H2C=CHSiMe(OSiMe3)2 without a significant drop in activity and selectivity. Results of a split test indicate that the source of catalytic activity is the catalyst immobilized in ionic liquid phase. [Copyright &y& Elsevier]

Abstract: Catalytic performance of styrene–divinylbenzene copolymer-supported platinum catalyst of high crosslinking degree and high surface area was studied in reactions of hydrosilylation of allyl chloride, 1-octene and 1-butene. The catalyst has shown considerably greater stability of catalytic activity than classical active carbon-supported catalyst. In experiments on repeated use of catalysts, the decrease in catalytic activity for hydrosilylation of liquid double bond-containing compounds proceeding in the presence of the copolymer-supported and carbon-supported platinum was considerably smaller in the case of the former catalyst. Bimetallic Pt–Cu catalyst on polymeric support appeared to be considerably less active than monometallic catalyst. [Copyright &y& Elsevier]

The bis(amino)silylene Si[(NCH2tBu)2C6H4-1,2] (&z.tbnd6; SiNN) behaved as a ligand in displacing COD or PPh3 from [Ni(COD)2], [Pt(PPh3)4] or [CuI(PPh3)3], yielding the crystalline d10 complexes [Ni(SiNN)4] (crystallised from Et2O as the 1:1-adduct 2), [Pt(PPh3)(SiNN)3] (5) or [CuI(PPh3)2(SiNN)] (6). Under the same conditions (in C6H6 at ambient temperature), SiNN and [MCl2(PPh3)2] yielded the crystalline (i) d8 complex trans-[M{SiNN(Cl)}2(SiNN)2] [M=Pt (3), Pd (4)] or (ii) the d10 complexes [Ni(PPh3)4−n(SiNN)n] (n=4 (2) or 3 (1), depending on stoichiometry; with Cl2SiNN as co-product). The X-ray structures of 2, 4, 5 and 6 are presented; those of 1 and 3 appeared in a preliminary communication. Compound 3 was shown to undergo three fluxional processes in CDCl3 solution, as shown by detailed variable temperature NMR spectroscopic experiments. These involved in order of increasing energy (a) two conformers of 3, (b) one of these and the cis-isomer, and (c) Si→Si 1,3-shifts of Cl−. These results are placed into the context of related published silylenemetal chemistry. [Copyright &y& Elsevier]

• Effective immobilization of Pt and Rh catalyst on the SILP materials containing MgO-SiO 2 and MgO-SiO 2 /lignin as supports. • Easy isolation and efficient reuse of SILP materials in subsequent catalytic cycles. • High catalytic activity and durability of Pt-SILP in hydrosilylation reaction. • SILPs materials with phosphonium and sulfonium ionic liquids active even in 15 catalytic cycles. New Supported Ionic Liquid Phase (SILP) materials on magnesium oxide-silica (MgO-SiO 2) and magnesium oxide-silica/lignin (MgO-SiO 2 /lignin) supports were obtained. The new SILP materials contain imidazolium, pyridinium, phosphonium and sulfonium cations and methylsulfate as well as bis (trifluoromethylsulfonyl)imide anions. The obtained systems were subjected to detailed physicochemical characterization by: XRD, SEM-EDX, elemental analysis, thermogravimetric measurements, IR spectroscopy and particle size determination. The adsorption properties of both, the supports and the obtained SILP materials, were additionally determined. The catalytic activity and possibility of reusing the obtained SILP systems were confirmed in the hydrosilylation reaction of 1-octene with 1,1,1,3,5,5,5-heptamethyltrisiloxane. [Display omitted] [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]

Functionalized siloxanes are one of the most important classes of organosilicon compounds, thus the enhancement of current methods of its synthesis is an important issue. Herein, we present the selective and highly effective reaction between 1,1,3,3-tetramethyldisiloxane (TMDSO) and 1-octene (1-oct), using SILP (supported ionic liquid phase) materials containing a rhodium catalyst immobilized in three phosphonium ionic liquids (ILs) differing in the structure of cation. Studies have shown high potential for using SILP materials as catalysts due to their high catalytic activity and selectivity, easy separation process, and the possibility of reusing the catalyst in subsequent reaction cycles without adding a new portion of the catalyst. Using the most active SILP material SiO2/[P66614][NTf2]/[{Rh(μ-OSiMe3)(cod)}2] allows for reuse of the catalyst at least 50 times in an efficient and highly selective monofunctionalization of TMDSO. [ABSTRACT FROM AUTHOR]

This mini-review briefly describes the recent progress in the design and development of catalysts based on the presence of ionic liquids. In particular, the focus was on heterogeneous systems (supported ionic liquid (IL) phase catalysts (SILPC), solid catalysts with ILs (SCILL), porous liquids), which due to the low amounts of ionic liquids needed for their production, eliminate basic problems observed in the case of the employment of ionic liquids in homogeneous systems, such as high price, high viscosity, and efficient isolation from post-reaction mixtures. [ABSTRACT FROM AUTHOR]

Six new air-stable anionic platinum complexes were synthesized in simple reactions of piperidinium [BMPip]Cl or pyrrolidinium [BMPyrr]Cl ionic liquids with platinum compounds ([Pt(cod)Cl2] or K2[PtCl6]). All these compounds were subjected to isolation and spectrometric characterization using NMR and ESI-MS techniques. Furthermore, the determination of melting points and thermal stability of the above derivatives was performed with the use of thermogravimetric analysis. The catalytic performance of the synthesized complexes was tested in hydrosilylation of 1-octene and allyl glycidyl ether with 1,1,1,3,5,5,5-heptamethyltrisiloxane. The study has shown that they have high catalytic activity and are insoluble in the reaction medium which enabled them to isolate and reuse them in consecutive catalytic cycles. The most active complex [BMPip]2[PtCl6] makes it possible to conduct at least 10 catalytic runs without losing activity which makes it an attractive alternative not only to commonly used homogeneous catalysts, but also to heterogeneous catalysts for hydrosilylation processes. The activity of the studied catalysts is also affected by the kind of anion and, to some extent, the kind of cation. [ABSTRACT FROM AUTHOR]

The earlier obtained organosilicon derivatives of rapeseed oil were used for the production of coatings protecting steel surface against corrosion. Vegetable oils have been hitherto used for temporary protection of metals against corrosion, while thanks to the synthesis of appropriate organosilicon derivatives, it is now possible to create durable protective coatings. Due to the presence of alkoxysilyl groups and the use of the sol-gel process, the coatings obtained were bonded to the steel surface. The effectiveness of the coatings was checked by electrochemical methods and steel surface analysis. [ABSTRACT FROM AUTHOR]

In order to eliminate the numerous limitations in application of cotton fibers, we designed and made a protective coating that changes many features of these material (such as water repellency or reducing the rate of thermal degradation), but does not change its natural flexibility and macroscopic appearance. The coating we developed consists a UV-crosslinked polysiloxanes together with organophosphates. The coating preparation process takes only a few minutes and takes place easily at room temperature. Even a very subtle layer of such a coating makes the fabric highly hydrophobic, and with greater occupancy, it significantly slows down thermal degradation and reduces the flammability of fabrics. A very interesting phenomenon observed by us is also the fact that the thicker the coating layer, the worse hydrophobic properties have been observed. The resulting coating is resistant to washing with both clean water and water with detergents., Competing Interests: Declaration of competing interest The authors of the publication titled: “Quickly UV-Curing Protective Coating for Cotton Fabrics” declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

This research describes the synthesis of a silane derivative containing phosphorus and nitrogen atoms, leveraging their synergistic flame retardant effect through the incorporation of a PH bond to the isocyanate moiety. The synthesized silane featured alkoxysilyl groups, facilitating permanent bonds with the cotton fabric surface via hydrolysis. Cotton fabrics were modified using silane solutions of varying concentrations (2.5 %, 5 %, and 10 %) through a dip-coating process to determine the effect of the modifier amount on fabric properties. The modified fabrics were subjected to FT-IR, TGA, SEM, and EDS analyses, as well as microcalorimetric and LOI tests, to assess changes in flammability. FT-IR, SEM/EDS, and add-on analyses confirmed effective coverage of the cotton fabric with the flame retardant. Thermogravimetric tests indicated a significant reduction in the mass loss rate during thermal degradation. LOI analyses demonstrated a decrease in flammability (increase in LOI value), while microcalorimetric tests showed a substantial decrease in the heat release rate, correlating with increased modifier concentration on the fabric surface. Post-washing analyses revealed that, although some of the modifier was washed out, the samples still retained reduced flammability., Competing Interests: Declaration of competing interest The authors have no relevant financial or non-financial interests to disclose., (Copyright © 2024 Elsevier B.V. All rights reserved.)

The article presents a very simple method of glass modification to obtain the anti-fog effect. Silanes containing two types of functional groups, namely a hydrophilic and polar polyether group and an alkoxysilyl group (to bond with the surface of the modified material) were synthesized in thiol-ene reactions. The hydrothiolation reactions of polyethers containing a C=C terminal bond with mercaptoalkoxysilane proceeded efficiently, yielding quantitatively appropriate products under mild reaction conditions. This method enabled the synthesis of a series of alkoxysilanes functionalized with polyethers, differing in structure. The group of obtained derivatives was characterized by 1 H, 13 C, 29 Si NMR, and FT-IR analyses, and then used to prepare coatings on glass using the sol-gel method. The coated glass surfaces exhibited transparency, superhydrophilic or hydrophilic properties, anti-fog and anti-frost performance., (© 2023. The Author(s).)

A simple and efficient method for the synthesis of organofunctional silanes by the thiol-(meth)acrylate addition reaction is presented. At first, systematic studies were carried out to select an optimum initiator/catalyst of the addition reaction for the model reaction involving 3-mercaptopropyltrimethoxysilane (MPTMS) and hexyl acrylate. Photoinitiators (in the presence of UV light energy), thermal initiators (such as aza compound and peroxide) as well as catalysts (primary and tertiary amines, phosphines and Lewis acid) were studied. After selecting an effective catalytic system and optimizing the reaction conditions, reactions between the thiol group ( i.e. 3-mercaptopropyltrimethoxysilane) and (meth)acrylates containing various functional groups were carried out. All derivatives obtained were characterized by 1 H, 13 C, 29 Si NMR and FT-IR analysis. In reactions carried out at room temperature, in an air atmosphere and in the presence of dimethylphenylphosphine (DMPP) as a catalyst, quantitative conversions of both substrates were obtained within a few minutes. The library of organofunctional silanes was expanded by compounds (containing various functional groups, i.e. alkenyl, epoxy, amino, ether, alkyl, aralkyl, fluoroalkyl) which were obtained in the thiol-Michael addition of 3-mercaptopropyltrimethoxysilane to a group of organofunctional (meth)acrylic acid esters., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

The aim of this study has been to examine in depth three siloxane resins (R1-R3) and two silanes (S1-S2) as hydrophobic self-cleaning layers for silicon and dye-sensitized solar cells. Herein, we focused on creating an active self-cleaning surface system using a combination of material and technical aspects. Siloxane resins were obtained via the hydrolytic polycondensation of methyltrimethoxysilane (R1) or the hydrolytic co-polycondensation of methyltrimethoxysilane, isobutyltrimethoxysilane and 3-methacroiloxypropyltrimethoxysilane (R2) or methyltrimethoxysilane n -octyltriethoxysilane and 3-methacroiloxypropyltrimethoxysilane (R3) under alkaline conditions using tetrahydrofuran. All layers under study did not significantly affect the original optical properties of the glass support, confirming that all these compounds can be used as protective layers on glass surfaces. The hydrophobic nature of formed layers was confirmed by static water contact angle measurements for hexane- and/or dibutyl ether-based starting solutions at various concentrations. The structural defects in created layers were studied via atomic force microscopy and thermal imaging, revealing RMS roughness ( R q ) values in the range of 0.76-5.25 nm, which varied for different materials. The current-voltage curves of different hydrophobic coatings showed conductive behaviour, demonstrating that principally non-conductive coatings mixed with silver conductive paste showed a certain level of conductivity. This finding suggests that the hydrophobic coating resembles a porous structure, enabling the formation of electrically conductive pathways. Finally, the influence of the presence of a coating layer on silicon and dye-sensitized solar cells was studied, and no negative effect on their photovoltaic parameters was observed after the durability test., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

While the formation and breaking of transition metal (TM)-carbon bonds plays a pivotal role in the catalysis of organic compounds, the reactivity of inorganometallic species, that is, those involving the transition metal (TM)-metalloid (E) bond, is of key importance in most conversions of metalloid derivatives catalyzed by TM complexes. This Review presents the background of inorganometallic catalysis and its development over the last 15 years. The results of mechanistic studies presented in the Review are related to the occurrence of TM-E and TM-H compounds as reactive intermediates in the catalytic transformations of selected metalloids (E = B, Si, Ge, Sn, As, Sb, or Te). The Review illustrates the significance of inorganometallics in catalysis of the following processes: addition of metalloid-hydrogen and metalloid-metalloid bonds to unsaturated compounds; activation and functionalization of C-H bonds and C-X bonds with hydrometalloids and bismetalloids; activation and functionalization of C-H bonds with vinylmetalloids, metalloid halides, and sulfonates; and dehydrocoupling of hydrometalloids. This first Review on inorganometallic catalysis sums up the developments in the catalytic methods for the synthesis of organometalloid compounds and their applications in advanced organic synthesis as a part of tandem reactions.

In the presented research, two trialkoxysilanes were used to investigate their reactivity with microcrystalline cellulose (MCC) applied as a model material. As a continuation of the previous study, the research aimed at evaluation of the durability and potential reversibility of the silane treatment. Two different solvents and a mixture thereof were used for cellulose modification. The influence of amino group/pH, an excess of silanes and re-soaking with water on binding with cellulose was examined. The results obtained confirm that both selected silanes can effectively modify MCC. However, the treatment with 3-(2-aminoethylamino)propyltrimethoxysilane occurred more effective than with Methyltrimethoxysilane due to the presence of amino groups. Among the three tested solvents, the most effective was pure water. In contrast, the use of ethanol and a mixture of ethanol and water gave significantly worse results. Summarising, the presented research clearly shows how important the type of the functional group in alkoxysilanes is for its chemical reactivity with natural polymers, which is crucial for their application in waterlogged wood conservation.

The oxide system TiO 2 -SiO 2 as well as a TiO 2 -SiO 2 /lignin system have been obtained by the sol-gel synthesis method and applied as supports in Supported Ionic Liquid Phase (SILP) materials. In total 24 SILP systems were obtained with ionic liquids containing imidazolium, pyridinium, phosphonium or sulfonic cations and bis(trifluoromethylsulfonyl)imide or methylsulfate anions, and homogeneous complexes of rhodium or platinum as the active phase. The supports and catalytic materials were subjected to thorough characterization by elemental analysis, XRD, SEM-EDX, IR, and TGA, and their particle size distribution and porous properties were assessed. The new SILP materials were used in hydrosilylation of 1-octene with 1,1,1,3,5,5,5-heptamethyltrisiloxane. The effectiveness of hydrosilylation reaction catalyzed by the obtained SILP materials for the polar and nonpolar reagents was assessed. All the catalytically active materials were proved to be easy to isolate and reuse, and the best SILP systems have been shown to be active in 10 or more subsequent catalytic cycles., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Binary mixtures of cholesterol and fully-condensed octakis[{2-(3,4-epoxycyclohexyl) etyl}dimethyl-silyloxy]octasilsesquioxane (OE-POSS) were characterized using Langmuir trough for obtaining surface pressure-area isotherms. The most characteristic feature of the mixed films is the presence of two collapse points on the isotherms. The first one is attributed to the collapse of less stable OE-POSS and it occurs at similar surface pressures for all compositions, while the second one corresponds to cholesterol collapse. Brewster angle microscopy observations confirmed the collapse behavior of the mixed film. Strong condensing effect was observed for the mean molecular areas dependence on cholesterol content in the film. Moreover, formation of microdomains of each component in the matrix of the other one was confirmed by BAM images. For the reasons of molecular structures and interactions a true mixed and homogenous film did not form in the systems considered. Phase separation was observed for all the compositions experimented. The lack of the interactions of OE-POSS with biomembrane components represented by cholesterol is beneficial for applications of OE-POSS in biomedical devices., (Copyright © 2015 Elsevier B.V. All rights reserved.)