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Hybrid materials with superior structural and functional properties can be obtained by incorporating nanofillers into polymer matrices. Polyhedral oligomeric silsesquioxane (POSS) nanoparticles have attracted much attention recently due to their nanometer size, the ease of which these particles can be incorporated into polymeric materials and the unique capability to reinforce polymers. We review here the state of POSS-containing polymer nanocomposites. We discuss the influence of the incorporation of POSS into polymer matrices via chemical cross-linking or physical blending on the structure of nanocomposites, as affected by surface functional groups, and the POSS concentration.

Water treatment residuals (WTRs) produced in large quantities during deironing and demanganization of infiltration water, due to high content of iron and manganese oxides, exhibit excellent sorptive properties toward arsenate and arsenite. Nonetheless, since they consist of microparticles, their practical use as an adsorbent is limited by difficulties with separation from treated solutions. The aim of this study was entrapment of chemically pretreated WTR into calcium alginate polymer and examination of sorptive properties of the obtained composite sorbent toward As(III) and As(V). Different products were formed varying in WTR content as well as in density of alginate matrix. In order to determine the key parameters of the adsorption process, both equilibrium and kinetic studies were conducted. The best properties were exhibited by a sorbent containing 5 % residuals, formed in alginate solution with a concentration of 1 %. In slightly acidic conditions (pH 4.5), its maximum sorption capacity was 3.4 and 2.9 mg g for As(III) and As(V), respectively. At neutral pH, the adsorption effectiveness decreased to 3.3 mg As g for arsenites and to 0.7 mg As g for arsenates. The presence of carboxylic groups in polymer chains impeded in neutral conditions the diffusion of anions into sorbent beads; therefore, the main rate-limiting step of the adsorption, mainly in the case of arsenates, was intraparticle diffusion. The optimal condition for simultaneous removal of arsenates and arsenites from water by means of the obtained composite sorbent is slightly acidic pH, ensuring similar adsorption effectiveness for both arsenic species. [ABSTRACT FROM AUTHOR]

Tetrathiafulvalene molecules substituted with a carboxylic acid group (TTFCOOH) were bound as redox-active moieties into a poly(4-vinyl pyridine) (P4VP) skeleton through non-covalent interactions (hydrogen bonds). The aspect of the resulting P4VP-TTFCOOH films showed a uniform and smooth morphology. Moreover, the redox function of TTFCOOH in P4VP-TTFCOOH was demonstrated using tetrachloroauric acid, iron(III) perchlorate and iodine vapors as doping agents. The oxidized states of TTFCOOH as well as the mixed valance state TTFCOOH 0 -TTFCOOH +• were generated in a controlled manner in solid state, resulting in an organic film capable of charge transport. The charge transport along the organic donor molecules hydrogen bonded to the polymer matrix was demonstrated employing Electrostatic Force Microscopy (EFM). [ABSTRACT FROM AUTHOR]

The aim of this article is to investigate the effect of the ratio of fillers, such as multiwalled carbon nanotubes (MWCNTs) and graphene nanoplatelets (GNPs), as well as different matrix stiffnesses, on the tensile strength of epoxy/polyester material. These fillers are added to epoxy/polyester solutions in various ratios and mixed well before molding. Experimental specimens are then made by means of the hot press process and utilizing the same curing and postcuring conditions. To investigate the effect of the matrix stiffness on the mechanical property reinforcement role of MWCNTs and GNPs in the resulting nanocomposites, the variations in the mixture ratios of the epoxy/polyester blend and hardener are considered. The results show that the tensile strength of epoxy/polyester material increases its maximum value by approximately 86.3% with the addition of MWCNTs at a ratio of 1% and increases to 86.8% with the addition of a mere 0.2% ratio of GNPs. The morphologies of the fractured surfaces of the resulting nanocomposites are observed by a scanning electron microscope (SEM). It is expected that the experimental results will lead to the offering of low-cost, high-strength materials for applications in the automobile industry and the manufacturing of household products. [ABSTRACT FROM AUTHOR]

The aim of this work was the study on the synthesis of hybrid polymers containing cupric hydroxide and oxide using as the supporting material macroreticular strong base anion exchanger. The first step of inorganic deposit introduction within the polymer matrix was precipitation of Cu(OH) 2 under different conditions (Cu(II) salt, temperature, duration). This stable product containing even 60 mg Cu(II) g − 1 was obtained by contacting anion exchanger in the OH − form with CuSO 4 solution. In the second step Cu(OH) 2 deposited in the polymer structure was converted into CuO under different conditions of which treatment with alkaline solution at a temperature of 50 °C occurred with the highest efficiency. Hybrid polymers with CuO deposit after two-steps synthesis contained 54 mg Cu(II) g − 1 . Simultaneously, by repeating the synthesis cycle twice it was possible to increase Cu(II) load to 119 mg g − 1 . The presence of cupric oxide was confirmed by XRD diffraction and FTIR analyses. SEM analyses showed that deposition of inorganic load occurred within the polymer matrix but in the outer parts of anion exchanger beads. Simultaneously, both obtained products containing Cu(OH) 2 and CuO had almost the same porous characteristics in comparison to host polymer (determined BET surface area reached values: 20.71, 21.04, 18.90 m 2 g − 1 respectively). [ABSTRACT FROM AUTHOR]

Polymeric encapsulation of a high surface energy inorganic can aid in its uniform dispersion in a composite coating. Here we systematically explored an approach to suitable encapsulation conditions for two specialized photoluminescent pigments. While a suspension-like process was desired to polymerize the layer at the inorganic surface, the robustness of the encapsulation was insufficient. By way of a simplified silica analog, proper conditions were determined to covalently link p(methyl methacrylate-co-glycidal methacrylate) latex particles to the inorganic surface through silane coupling. Those conditions were then successfully leveraged to the irregularly shaped photoluminescent pigments without deleterious impact on phosphorescence emission spectra nor on the persistence of the emission. [ABSTRACT FROM AUTHOR]

A polyurethane/polyhydroxyurethane (PU/PHU) hybrid polymer was synthesized by reaction of a cyclic-carbonate-terminated prepolymer with triethylenetetramine without employing isocyanates in the final curing step. This cured elastomer contains traditional urethane linkages from the initial prepolymer reaction as well as hydroxyurethane linkages from the final chain extension reaction. The PU/PHU hybrid exhibits microphase separation as made apparent by the presence of two glass transitions and elastomeric properties with Young's modulus of 37 MPa and strain at break of 350%. Most importantly, the PU/PHU hybrid polymer exhibits adhesion to polyimide, poly(vinyl chloride) (PVC), and aluminum substrates that is similar to or enhanced relative to those of polyurethane controls and literature values for typical polyurethane adhesives. In particular, the PU/PHU hybrid has T-peel forces of 7.8, 10.5, and 3.4 N/mm on polyimide, PVC, and aluminum, respectively, and undergoes predominantly cohesive failure rather than adhesive failure. The application of this material as a model consumer-applied adhesive for potential replacement of isocyanate-based polyurethanes is also briefly discussed. [ABSTRACT FROM AUTHOR]

The synthesis of new materials of hybrid character (organic-inorganic) doped with dyes results highly attractive like active medium in solid state laser in which the excellent thermal properties of the inorganic glasses with the excellent optic properties of the polymeric materials could be combined. Through a simultaneous synthesis process of sol-gel policondensation of the inorganic TEOS during the free radical polymerization of the organic part (vinylic or acrylic monomers with OH groups), since the presence of this -OH side groups in the organic monomer can participate in the policondensation process of silanols, hybrids monoliths were able to be obtained as solid-state dye laser matrices. The synthesis and characterization of new hybrid matrices were carried out incorporating pirromethene 567 (PM567) into polymers of 2-hydroxyethyl methacrylate (HEMA) and copolymers of HEMA and methyl methacrylate (MMA) with different weight proportions of the inorganic component, tetraethoxysilane (TEOS). The first results obtained with this new materials are indicave that the addition of low proportions of TEOS into the polymer P(HEMA/MMA 1/1) increases its thermal stability reducing the thermal degradation of the dye and, consequently, improving significantly its laser action. In fact, some of the results achieved with these new materials represent the best photostability reached to date for PM567 incorporated into inorganic and hybrid materials and, taking into account the experimental pumping conditions, improve or at least, compare well, with the lasing properties of the dye embedded in other host polymeric matrices.La síntesis de nuevos materiales de carácter híbrido (orgánico-inorgánico) dopados con colorantes resultan altamente atractivos como medio activo en láseres de estado sólido ya que permiten combinar las excelentes propiedades térmicas que presentan los vidrios inorgánicos con las excelentes propiedades ópticas que presentan los materiales polímeros. Mediante un proceso simultaneo de policondensación sol-gel y de polimerización de la parte orgánica (monómero vinílico ó acrílico con grupos OH), de forma que los grupos –OH del monómero orgánico participen también en el proceso de policondensación, hemos conseguido obtener monolitos válidos para su aplicación como láseres de colorante en estado sólido. Se ha llevado a cabo la síntesis y caracterización de nuevas matrices híbridas incorporando pirrometeno 567 como colorante láser (PM567); combinando polímeros de metacrilato de 2-hidroxietilo (HEMA) y copolímeros de HEMA y metacrilato de metilo (MMA) con diferentes proporciones en peso respecto al componente inorgánico (TEOS). Los primeros resultados obtenidos con estos nuevos materiales demuestran que la presencia de pequeñas proporciones de TEOS en copolímeros de p(HEMA/MMA 1/1) aumentan la estabilidad térmica del colorante mejorando significativamente su acción láser. De hecho, algunos de los resultados alcanzados con estos nuevos materiales mejoran, significativamente, las fotoestabilidades alcanzadas para el PM567 incorporado en otras matrices inorgánicas e híbridas, así como en muchas de las matrices orgánicas seleccionadas como hospedadores para este colorante.

Embedded channel waveguide Bragg gratings are fabricated in the Ormocer® hybrid polymers OrmoComp®, OrmoCore, and OrmoClad by employing a single writing step technique based on phase mask technology and KrF excimer laser irradiation. All waveguide Bragg gratings exhibit well-defined reflection peaks within the telecom wavelengths range with peak heights of up to 35 dB and −3 dB-bandwidths of down to 95 pm. Furthermore, the dependency of the fabricated embedded channel waveguide Bragg gratings on changes of the temperature and relative humidity are investigated. Here, we found that the Bragg grating in OrmoComp® is significantly influenced by humidity variations, while the Bragg gratings in OrmoCore and OrmoClad exhibit linear and considerably high temperature sensitivities of up to −250 pm/ ∘ C and a linear dependency on the relative humidity in the range of −9 pm/%.

[Display omitted] • A novel DVP hybrid polymer was prepared for adsorption of Pb(II). • The maximum adsorption capacity of DVP for Pb(II) reached 349.5 mg g−1. • The Pb(II) removal performance was little affected by increased hardness cations. • The synergistic adsorption mechanism of thioether and carboxyl groups was proposed. It is a challenging task to remove Pb(II) ions efficiently from wastewater containing high concentrations of hardness ions. In this study, a novel hybrid polymer (DVP) for selective adsorption of Pb(II) ions was successfully prepared via photopolymerization of vinyl-POSS and dimercaptosuccinic acid (DMSA). The chemical structure and composition of DVP were characterized by FTIR, XPS, SEM, TEM, XRD and TGA techniques. DVP exhibited high efficiency in removing Pb(II) from aqueous solutions with a maximum adsorption capacity of 349.5 mg g−1 at pH 4, exceeding lots of adsorbents reported in the literature. The adsorption performance of Pb(II) by DVP was found to fit the Freundlich isotherm well and its kinetics followed the Elovich model. Moreover, DVP showed selective adsorption of Pb(II) in the presence of high concentrations of Ca(II) and Mg(II) ions and could reduce Pb(II) in real lake water to 25 ppb at a DVP dose of 1 g L−1. Moreover, the adsorption process of DVP was endothermic in nature. The adsorption mechanism demonstrated that Pb(II) ions can be chelated with the thioether and carboxyl groups of DVP simultaneously, which was confirmed by spectroscopic analysis and DFT calculations. Good reusability in continuous fixed-bed column experiments suggested that DVP was an ideal candidate for the selective removal of Pb(II) ions from contaminated aquatic systems. [ABSTRACT FROM AUTHOR]

This paper describes fabrication of conductive, highly adhesive silver (Ag) micropatterns on transparent flexible double-decker-shaped polysilsesquioxane (DDPSQ) film by a laser direct writing technique using a precursor film prepared from liquid-dispersed Ag nanoparticles. The laser-written Ag micropatterns have been characterized by optical microscopy, field-emission scanning electron microscopy, surface profilometry, and resistivity measurements. The line width of the Ag micropatterns can be flexibly controlled by changing the objective lens magnification and laser spot size. Using a ×100 objective lens and laser energy density of 170.50 kW/cm, Ag micropatterns with line width of about 4 μm have been achieved. The Ag micropatterns show excellent adherence to the DDPSQ surface as evaluated by Scotch-tape test. The resistivity of the Ag micropatterns has been determined to be 4.1 × 10 Ω cm using the two-point probe method, being almost comparable to that of bulk Ag (1.6 × 10 Ω cm). Thus, high-quality, narrow, homogeneous Ag microlines with high conductivity and adhesion can be produced under optimized laser scanning conditions. [ABSTRACT FROM AUTHOR]

The effect of graphene on the corrosion inhibition properties of a hybrid epoxy–ester–siloxane–urea polymer was investigated. The weight fraction of graphene was varied from 1 to 2 wt%. Direct current polarization (DCP) and electrochemical impedance spectroscopic (EIS) techniques were used to measure the polarization and coating resistance of the coated aluminum alloy substrate. The grapheme/hybrid polymer composite coatings showed much higher corrosion inhibition property when compared to the neat hybrid polymer coating. An increase in glass transition temperature and rubbery region modulus was also observed for composites containing 1–2 wt.% of graphene. A direct correlation between the rubbery plateau modulus of free standing composite thin films and corrosion resistance of the composite coatings was made, indicating that the corrosion protection mechanism is due to restriction of the polymer chain motion by graphene which causes a decrease in coating permeability. [ABSTRACT FROM AUTHOR]

Hybrid hydrogel materials derived from two types of polymethacrylates: rigid and flexible, crosslinked with methacryloxy-multifunctionalized polyhedral oligomeric silsesquioxane (M-POSS) were obtained in a photo-induced copolymerization process. The base monomers were 2-hydroxyethyl methacrylate (HEMA; forming a rigid polymer) and a mixture of oxyethylene glycol (di)methacrylates (forming an elastomer). Investigations included the kinetics of hybrid materials formation and selected physical and mechanical properties. The obtained results were discussed in terms of effects of H-bonding and viscosity of compositions before curing, additional crosslinking, the presence of POSS cage, M-POSS aggregation and rigidity/flexibility of the base polymer. It was found that physical factors (diffusion, tendency to aggregation) dominate over interactions between reacting molecules (H-bonding) during the formation of the hybrid polymer structure. Disorder in H-bonding in HEMA-based material is responsible for the appearance of the antiplasticization effect manifesting itself by the lowering of the T g value with simultaneous increase in the Young modulus. Antiplasticization behavior affects also thermal stability of the HEMA-based materials. In general, cross-linking of the rigid and elastomeric material with M-POSS gives quite different results; moreover, the HEMA-based materials show an exceptional behavior. The results presented are important indications in the selection of technological curing parameters in preparation of M-POSS-containing hydrogel materials. [ABSTRACT FROM AUTHOR]

In this study, a new ferrocenyldithiophosphonate functionalized; [ O-1-(4-phenyl)-1 H-pyrrole ferrocenyldithiophosphonate (TPFc)] monomer and its conductive copolymers with pyrrole and 4-(2,5-di(thiophen-2-yl)-1 H-pyrrol-1-yl)butane-1-amine were synthesized, characterized and their electrochromic properties were investigated. The spectroelectrochemical analyses demonstrated that the copolymer films reveal a reversible cycling with distinctive color changes in their reduced/oxidized forms. For the copolymer films P(TPFc- co-Py)/DCM, P(TPFc- co-Py)/CHCN and P(TPFc- co-TPA)/DCM, the maximum optical contrasts (ΔT %) were measured as 28, 12 and 27 % at 800, 900 and 900 nm, respectively. Spectroelectrochemical analysis also revealed that all copolymers prepared with TPFc have lower band gaps compared to those of corresponding polymers. [ABSTRACT FROM AUTHOR]

We report the fabrication of silicon oxycarbide (SiOC) ceramics with high surface area and porosity and a hierarchical pore structure. They have been synthesized using polymer blends that consist of allyl hydridopolycarbosilane (AHPCS) and hydridopolycarbosilane (HPCS) as the precursors. Layered double hydroxides (LDHs), modified by sodium dodecylbenzenesulfonate (SDBS), a common surfactant, are used as a sacrificial template, and a simple impregnation technique is employed to enable the polymer precursor to penetrate into the LDH structure. Various characterization methods, such as XRD, XPS, and SEM-EDX, are used to verify that the ceramics that are produced are SiOC materials. A key aspect of the fabrication process is the use of pre-ceramic polymer blends that are capable of producing ceramics with an interconnected porous space. Air calcination of the as-prepared SiOC ceramic removes any free carbon that is present, but preserves the pore structure of the material. The SEM images indicate that the materials' internal pore structure consists of well-aligned, slit-like pores. Nitrogen sorption measurements demonstrate that the material fabricated from polymer blend AHPCS/HPCS = 2:1 has surface areas as high as 811.7 m 2 /g, total pore volume as large as 0.80 cm 3 /g with considerable fractions of micro- and mesopores. The synthesis method that we have developed uses low-cost pre-ceramic polymer precursors and templates and generates porous SiOC ceramics with high surface area, interconnected pore space with a multi-modal pore size distribution, and high-temperature stability. As such, the technique may be considered as a convenient and cost-effective approach for the fabrication of a wide class of porous materials for such applications as catalysis, gas adsorption/separation under harsh conditions, and biomedical device uses, etc. [ABSTRACT FROM AUTHOR]

An organic-inorganic hybrid polymer, composed of poly(methylsilsesquioxane) (PMSSQ) and poly(4-vinyl benzaldehyde) (PStCHO), is prepared by reversible addition-fragmentation chain transfer (RAFT) polymerization of 4-vinyl benzaldehyde (StCHO) using a macro-chain transfer agent (CTA) based on PMSSQ. The obtained PMSSQ-PStCHO is spin-coated on substrates such as silicon wafers or copper plates to afford aldehyde-functionalized surfaces. Successful Kabachnik-Fields post-polymerization modification (KF-PMR) of the aldehyde-functionalized surfaces is conducted with amines and dialkyl phosphonates, and characterized by surface analysis techniques including IR, energy-dispersive X-ray (EDX), and X-ray photoelectron spectroscopy (XPS) measurements, documenting the installation of α-amino phosphonates onto surfaces with practically quantitative conversion of aldehydes. In addition, the generated α-amino phosphonates are successfully deprotected to afford the corresponding α-amino phosphonic acids on surfaces, which make this route a reliable tool-enabling surface functionalization with α-amino phosphonic acids. [ABSTRACT FROM AUTHOR]

Novel cost efficient high barrier envelopes are developed for vacuum insulation panels. In order to fulfil the required maximum oxygen permeability (at 23 °C and 50% relative humidity (RH)) of 1 × 10 −14 m 3 (STP) m −2 day −1 Pa −1 and water vapour transmission rate (at 23 °C and 85% → 0% RH) of 1 × 10 −6 kg m −2 day −1 , hybrid polymeric (ORMOCER ® ) and aluminium barrier layers are combined. Using roll-to-roll processes, these materials are deposited from the liquid or gas phase on top of a poly(ethylene terephthalate) substrate film. The low adhesion strength observed between aluminium and ORMOCER ® layers is significantly increased by the deposition of an additional aluminium oxide layer between the two materials. The lamination of a polyethylene or polypropylene sealing film does not weaken the adhesion strength. The resulting barrier structure has reached an oxygen permeability of lower than 5 × 10 −14 m 3 (STP) m −2 day −1 Pa −1 (at 37 °C and 30% RH). Electrochemical impedance spectroscopy gives evidence for a possible penetration of the ORMOCER ® lacquer into the aluminium oxide layer (synergistic effect), which explains the improved adhesion and barrier performance due to the aluminium oxide layer. [ABSTRACT FROM AUTHOR]

When water adsorbing particles are hybridized into urethane foam, the height of water adsorption and the water-holding capacity are both increased. Using this effect, we can use the hybrid urethane foam as "artificial soil". If adsorptive capacity is given to the particles, e.g., for specific ions, the artificial soil inherits this property. If the adsorbency is specific for nitric acid, plants can use the adsorbed nitrogen of nitric acid as fertilizer. Nitrate-nitrogen is one of the pollutants in water. In this research, we investigate artificial soils with a hybrid material that adsorbs nitric acid, i.e. it can adsorb nitrate ions. As a result, we show that hybrid urethane foam can adsorb nitrate ions. In addition, we grew plants in such artificial soils, and showed that plants could use the adsorbed nitrate-nitrogen as fertilizer. If control of hardness of hybrid artificial soil, determintion of suitable amount of adsorbent and base materials other than urethane foam can be achieved, we can obtain hybrid artificial soils with encouraging properties for the growth of plants. [ABSTRACT FROM AUTHOR]

The present contribution provides a strategy to enhance the dielectric constant of polyethylene by chemical modification while not overly compromising its large band gap. Isolated polyethylene chains are considered and the CH2 motifs in the backbone are allowed to be substituted by a number of Group 14 motifs, including SiF2, SiCl2, GeF2, GeCl2, SnF2, and SnCl2, in a systematic, progressive, and exhaustive combinatorial manner. Our results indicate that consecutive SnF2 or GeF2 motifs in the polyethylene backbone are most desirable, which can lead to systems with dielectric constant as high as 47. [ABSTRACT FROM AUTHOR]

In this study, hybrid polyacrylic acid and Schizochytrium sp. microalgae (PAA/Schizo) microgels were synthesized by inverse emulsion assisted by ultrasound using the cell wall fraction as crosslinker. Physicochemical characterization of PAA/Schizo microgels revealed polymeric spherical particles (288 ± 39 nm) and were deemed stable and negatively charged. The produced microgels are not inherently toxic as cell viability was sustained above 80% when mice splenocytes were exposed to concentrations ranging 10-900 µg/mL. PAA/Schizo microgels were evaluated as antigen delivery nanovehicle by adsorbing bovine serum albumin (BSA); with a loading efficiency of 72% and loading capacity of 362 µg/mg. Overall, intranasally-immunized BALB/c mice showed null IgG or IgA responses against PAA/Schizo microgel-BSA, whereas soluble BSA induced significant humoral responses in systemic and mucosal compartments. Splenocytes proliferation assay upon BSA stimulus revealed positive CD4+ T cells-proliferation response in PAA/Schizo microgels-BSA group. Thus, PAA/Schizo microgels constitute functional antigen delivery vehicles of simple and ecofriendly synthesis. Moreover, the use of cell wall fraction as cross-linker agent provides an alternative use for the generation of high-value products using residual algae biomass from the oil industry. Our data suggests that the PAA/Schizo microgels are potential antigen delivery vehicles for immunotherapy development.

Abstract: Over the last decade, significant advances have been made toward the development of practical, tunable solid state dye lasers, which resulted in improved lasing efficiency with reduced dye photodegradation. To achieve this goal, a “chemical” approach was followed, where attention was focused onto the particular dye/host interaction and compatibility, specifically choosing already existing hosts for a given dye, synthesizing new dyes and/or matrices, or chemically modifying existing ones. Nevertheless, this approach was limited by a single fact learnt from the experience: there is no universal matrix which optimizes the efficiency and photostability of all dyes. This limitation could be overcome by following a “physical” approach, where the emission properties of the active medium are tailored by means of physical and structural modifications of the dye host. Following this approach, in this paper recent theoretical and experimental work is reviewed where it is demonstrated that following a simultaneous “physical” and “chemical” approach to tailor the emission properties of the host materials for solid state dye lasers, may lead, under specific circumstances, to the improvement of both the laser efficiency and photostability. In particular, it is demonstrated that optical scattering is not always detrimental either to conventional bulk lasers (laser rods or colloidal suspensions) or to integrated devices, but may give place, on the contrary, to dramatic improvements in the laser operation of organic (hybrid) laser rods, and to alternative ways of obtaining laser light from integrated devices based on the phenomenon of coherent random lasing, where feedback is provided by light scattering in an appropriate medium, without the need to manufacture complex periodic structures in the substrate. The processing and pumping flexibility of these materials, together with their low cost and capability of efficient emission across the whole visible spectrum makes them very attractive for the fabrication and development of coherent light sources suitable for integration in optoelectronic and disposable spectroscopic and sensing devices. [Copyright &y& Elsevier]

Siloxane-based polymer was synthesized through hydrosilylation of the 1,3,5,7-tetramethylcyclotetrasiloxane (TMCS) and 1,3-divinyltetramethylsiloxane (DTMS). Controlling the hydrosilylation reaction by varying the feeding ratio with the total monomer concentration, chemically-soluble siloxane-based polymer was obtained, which allowed film preparation as well as further incorporation of functional groups through the hydrosilylation reaction. The incorporation of 9-vinylanthracene was succesfully carried out by reacting Si-H groups of the TMCS−DTMS polymer with the vinyl-terminated anthracene derivative. Structural and thermal properties of the polymer were evaluated using NMR, GPC, FT−IR and flourecence spectroscopy. [ABSTRACT FROM AUTHOR]

Abstract: In this paper we describe the synthesis, characterization and proton conductivity of azole-substituted cyclic and polymeric phosphazenes. All of the cyclic compounds HTCP, OTCP and polymer, PVTP were fully characterized by elemental analysis, FT-IR, 1H, 13C and 31P NMR spectroscopy. Thermal properties of newly synthesized compounds were investigated with TGA&DSC and the anhydrous proton conductivity was measured by impedance spectroscopy at selected temperatures. It was found that, maximum proton conductivity of 0.043 S cm−1 was obtained for PVTP, which is doped with trifluoromethane sulfonic acid, at 150 °C without decomposition. The cyclic derivative HTCP has been obtained as triclinic crystals in P − 1 space group with two water molecules in asymmetric unit. The X-ray structural characterization result supported that the proton transfer has been ensured by Grotthuss mechanism. [Copyright &y& Elsevier]

Hybrid materials with superior structural and functional properties can be obtained by incorporating nanofillers into polymer matrices. Polyhedral oligomeric silsesquioxane (POSS) nanoparticles have attracted much attention recently due to their nanometer size, the ease of which these particles can be incorporated into polymeric materials and the unique capability to reinforce polymers. We review here the state of POSS-containing polymer nanocomposites. We discuss the influence of the incorporation of POSS into polymer matrices via chemical cross-linking or physical blending on the structure of nanocomposites, as affected by surface functional groups, and the POSS concentration. [ABSTRACT FROM AUTHOR]

Abstract: The removal of C.I. Reactive Blue 19 dye at initial concentration of 1000mg/L was studied using iron scrap process and coagulation/flocculation by a novel synthesized Al(OH)3–PAM inorganic–organic hybrid polymer. A novel synthesized Al(OH)3–PAM was prepared using a redox initiation system while (NH4)2S2O8 and NaHSO3 were used to initiate the polymerization at 50°C in aqueous medium. The Al(OH)3–PAM was characterized using FT-IR spectroscopy, TEM, and XRD. pH of dye solution and Al(OH)3–PAM dosage have been studied while COD reduction and color removal in different settling times were investigated. The results show that 26% of (COD) content and 45% of color have been removed by iron scrap process. Meanwhile 90% of the color and 82% of COD have been removed by Al(OH)3–PAM hybrid polymer in an optimum dosage of 700mg/L and optimum effective pH between pH of 5–6. [Copyright &y& Elsevier]

Abstract: With its potential to produce stackable solids for backfill (land reclamation) and the highest quality and quantity of water (filtrate) for recycle, filtration for treating mature fine tailings (MFT) using an in-house synthesized, organic–inorganic hybrid polymer (flocculant), Al-PAM, as a filtration aid was developed and tested on a MFT from oil sands operations. After proper dilution of the MFT from 30wt% to 10wt% solids, Al-PAM was found to be an effective filtration aid. A two-step process: Al-PAM flocculation and thickening of diluted MFT, followed by filtration of thickener underflow to produce a stackable filter cake and virtually solids-free filtrate was found to be the most appealing. This study clearly showed that Al-PAM assisted filtration is a viable solution to reduce the inventory of MFT and associated liability while maximizing recovery (recycle) of process-affected water. [Copyright &y& Elsevier]

Abstract: Long-wavelength (660–740nm) coherent random lasing (RL) in slab waveguides consisting of poly(2-hydroxyethyl methacrylate) (pHEMA) incorporating silsesquioxane nanoparticles (POSS) doped with the red-emitting dyes LDS722 and LDS730 is presented. Energy transfer from a donor dye is used to overcome the inherent low pump (532nm) absorption of these dyes and to enhance the lasing efficiency of the samples. Rhodamine 6G is used as donor for LDS722 and Sulforhodamine B as donor for LDS730, in donor/acceptor molar proportions 3.3/6.6 and 1/9, respectively. RL emission spectral fingerprints and thresholds are studied in depth and insights into the RL characteristics are obtained from the Power Fourier Transforms of the emission spectra. Finally, photostabilities of LDS722 and, for the first time, of LDS730 doped into polymer slab waveguides are assessed. [Copyright &y& Elsevier]

Abstract: Iron oxide modified polyglycidyl methacrylate graft copolymer (PGMA) hybrid adsorbent (PGMAFe), have been synthesized and characterized; and their use in Cr(VI) removal was studied. The adsorption capacities were determined at different pH values. The results showed the adsorption efficiency was highly pH dependent. Cr(VI) adsorption data were well fitted with the Freundlich adsorption isotherm model. The maximum Cr(VI) adsorption capacities of PGMA and PGMAFe sorbents were obtained at pH 4 as 132.5 and 162.9mg/g, respectively. The results of the kinetic experiments showed that Cr(VI) adsorption onto both sorbents followed the pseudo-second-order kinetic model. A series of column experiments were carried out to determine the breakthrough curves. The column was regenerated by eluting Cr(VI) with NaOH (10%, w/v) solution. [Copyright &y& Elsevier]

A route to a large variety of functionalized POSS compounds by a two-step procedure has been developed. Up-scaling to high volume industrial applications is feasible. In the first step, an amino-functionalized silane such as 3-aminopropyltriethoxy silane is converted to amino-functionalized POSS (amine-POSS) by a sol-gel process. In the second step, the amine groups of amine-POSS are converted by state-of-the-art amine chemistry. A large number of reactants including carboxylic acids, esters, anhydrides, isocyanates, carbonates, epoxides, and acrylates as well as reactants suitable for nucleophilic substitution can be applied. Conversion of an amine-POSS with hexanoic acid leads to an amide-POSS. Amine chemistry can usually be performed under mild conditions, which suppresses degradation and/or cross-linking reactions of the amine-POSS during the conversion. MALDI-TOF mass spectroscopy and dynamic light scattering (particle size: 3-6 nm) have been applied to prove the conversion of an amine-POSS to an amide-POSS. H-NMR and TGA-MS prove the presence of amide-POSS and its thermal stability. Gas barrier properties of nanocomposite coatings based on functionalized POSS are characterized. [ABSTRACT FROM AUTHOR]

Abstract: A straight-forward fabrication process was developed for hybrid layered molds consisting of a flexible metal plate as a mechanical support covered with a sol–gel layer with a nanostructured surface relief. The bendable stamp was tested under high speed roll-to-roll (R2R) manufacturing condition. A sufficient stamp lifetime was found, since no structural degradation was observed after a continuous imprint of more than 40m. Thus, it is shown that hybrid molds are good and inexpensive alternatives to electroplated shims usually used in R2R embossing. [Copyright &y& Elsevier]

Abstract: A ferric chloride–polyacrylamide inorganic–organic hybrid polymer has been synthesized using a ferric chloride/polyacrylamide ratio of 1:1 via free radical solution polymerization. A redox initiation system - (NH4)2S2O8 and NaHSO3 was used to initiate the polymerization at 50°C in aqueous medium. The ferric chloride–polyacrylamide hybrid polymer was characterized using Fourier transform infrared (FT-IR) spectrometer to determine their functional groups in the hybrid polymer chain. The FeCl3-PAM hybrid polymer was tested for flocculating activities on kaolin suspension and Terasil Red R dye wastewater. Parameters such as solution pH and FeCl3-PAM hybrid polymer dosage have been studied. One-way ANOVA shows that pH has a significant impact (p <0.05) in flocculating both kaolin suspension and Terasil Red R wastewater. The results show a minimum dosage of 2mg/L is able to remove more than 99% of turbidity in kaolin suspension at pH 2. FeCl3-PAM hybrid polymer also shows its capability in flocculating Terasil Red R dye wastewater. It is able to reduce 89% of COD and 99% of colour at pH 5 using 500mg/L of dosage. [ABSTRACT FROM AUTHOR]

Abstract: One of the major scientific and technological challenges for the production of flexible organic electronic devices is the device protection against atmospheric molecule permeation, which causes corrosion reducing its operation and lifetime. In this work, Spectroscopic Ellipsometry has been implemented to investigate the influence of silicon dioxide nanoparticles on the optical properties of hybrid polymers. The spectra analysis revealed valuable information about the electronic and vibrational response as well as the cross-linking mechanisms of these materials. The correlation of the optical properties with the synthesis parameters and the barrier response will contribute towards their optimization in order to be used as high barrier coatings for flexible organic electronics applications. [Copyright &y& Elsevier]

We computed by a tight binding calculation taking into account hybridization, the total electronic energy of different connectivities (amorphous, fractal and linear) of (Si−(CH3)2) n−(OSiO) p(OH) q. We found that the total electronic energy of the amorphous connectivity was the smallest as a function of the number of atoms contained by the hybrid polymer. As the total electronic energy is linked to the stability, we may say that the connectivity of such hybrid polymer has the highest stability for the amorphous connectivity. [ABSTRACT FROM AUTHOR]

Abstract: This paper describes fabrication of silver (Ag) micropatterns on a double-decker-shaped polysilsesquioxane (DDPSQ) hybrid film by laser-induced pyrolysis (LIP) of a film prepared from liquid-dispersed Ag nanoparticles. The line width of Ag micropatterns fabricated by LIP can be controlled flexibly by changing the numerical aperture (NA) value of an objective lens and the focusing point. By changing NA value of an objective lens, line widths of Ag micropatterns can be varied flexibly from 75 μm to 5 μm. The Ag micropatterns show an excellent adherence to DDPSQ surface as evaluated by adhesive tape test. The resistivity of the Ag micropattern is determined to be 4.3×10−6 Ω cm, which is comparable to that of bulk Ag (1.6×10−6 Ω cm). [Copyright &y& Elsevier]

Abstract: Hybrid (inorganic–organic) polymer materials deposited onto flexible polymeric substrates can provide sufficient barrier response against oxygen and water vapor penetration. In the case that they are combined with inorganic oxide layers (e.g. SiO x , AlO x ) in multilayered structures onto flexible polymeric substrates, they can achieve barrier values for oxygen and water vapor below 10−3 cm3 m−2 d−1 bar−1 and 10−3 gm−2 d−1, respectively. The in depth knowledge of their optical properties can provide significant insights on their structure and it will contribute towards the optimization of their barrier response. In this work, Spectroscopic Ellipsometry from the infrared to the visible–ultraviolet has been implemented for the investigation of the influence of silicon dioxide nanoparticles, which have been added in the hybrid material during its synthesis, in order to strengthen the inorganic–organic network, on the optical properties of hybrid polymers. The performed analysis revealed valuable information about the electronic and vibrational response as well as the crosslinking mechanisms of these materials. The correlation of the optical properties with the synthesis parameters and the barrier response will contribute towards their optimization in order to be widely used as ultra high barrier materials for flexible organic electronics. [Copyright &y& Elsevier]

New hybrid poly(phenylenemethylene) with functionalized polyhedral oligomeric silsesquioxanes (PPM-POSS) and poly(phenylenemethylene) with benzyl moieties (PPM-Benzyl) were prepared by the reaction of POSS-DMP or Benzyl-DMP and paraformaldehyde, respectively. The synthesized polymers could be well characterized by ¹H NMR, ET-IR, DSC, TGA, and EDS. This type of hybrid poly(phenylenemethylene) containing side-chain-tethered POSS pendant units consists of a linear rigid-rod poly(phenylenemethylene) in the main chain and POSS branches as inorganic parts attached to the main chain. This particular molecular architecture of hybrid PPM-POSS possesses the higher thermal decomposition and no glass transition temperatures relative to those of PPM-Benzyl with no POSS units. Furthermore, PPM-POSS shows very uniform distribution of spherical particles with a mean diameter 100 nm, while PPM-Benzyl shows uneven and large spherical particles with 1-5 μm size, as evidenced by scanning electron microscopy studies. [ABSTRACT FROM AUTHOR]

Abstract: Inorganic–organic hybrid polymers were prepared by co-polymerization of styrene or methyl methacrylate in the presence of small proportions of the cluster Zr4O2(methacrylate)12. The thermal properties of the hybrid polymers were improved by the cluster-crosslinking. Variation of the reaction conditions had little influence on the thermal properties, although the gelation times were clearly influenced. The cluster-crosslinks were completely and selectively degraded by means of acetylacetone. This allowed the unique possibility of determining the number average molecular weights and polydispersities of the organic polymers which were initially interconnected by the clusters. [Copyright &y& Elsevier]

Abstract: Inorganic–organic hybrid materials were prepared by step-wise free radical polymerization of styrene in the presence of zirconium oxo clusters of the general compositions Zr6O4(OH)4(carboxylate)12 (carboxylate=5-norbornene-2-carboxylate or isobutyrate/methacrylate) and Zr12O8(OH)8(carboxylate)24 (carboxylate=acetate/propionate, vinylacetate, or acetate/methacrylate). Clusters with non-polymerizable ligands resulted in cluster/polystyrene blends which were soluble in toluene, whereas clusters with polymerizable ligands gave cluster-crosslinked, swellable polymers for which solvent uptake correlated with the functionality of the corresponding cluster. The onset temperatures of thermal decomposition and the glass transition temperatures of all cluster-containing polymers were higher than that of neat polystyrene, independent of whether the clusters were crosslinking or blended into the polymer. [Copyright &y& Elsevier]

Abstract: Barrier films deposited on flexible substrates are indispensable for a lot of applications. These are, for example, flexible displays based on LCD or OLED devices, flexible solar modules, materials for thermal insulation (e.g., vacuum insulated panels) or food packaging. The abovementioned applications already reveal very different requirements of barrier properties. Barrier films for food packaging for example can be produced with a single evaporated film, whereas the encapsulation of LCDs or OLED devices on flexible substrates is more sophisticated. In general, the approach of a complex multilayer system is used to fulfil the requirements for these ultrabarrier applications. In addition to their barrier properties, these multilayer systems also have to exhibit high transparency for many applications. In this case, a layer system can be used, that is based on sputtered Al2O3 layers, which are separated by different types of intermediate smoothing layers. This paper describes the concept and development of the Fraunhofer PolO alliance (www.polo.fhg.de) with regard to ultrabarriers for different applications. The barrier improvement of sputtered Al2O3 films deposited in a roll to roll process is analyzed. Further, the lacquering of inorganic organic hybrid polymers (Ormocers®) is described and synergetic effects from the use of the hybrid polymers in combination with sputtered Al2O3 films are discussed. Finally the assembly of an all flexible OLED test device is described, showing the suitability of complex multilayer systems for ultrabarrier applications. [Copyright &y& Elsevier]

Abstract: Well defined oligo(phenylene vinylene) grafted polymers known as oligo(phenylene vinylene)–poly(methylstyrene) hybrids have been developed using a step-wise synthetic protocol, where the length of the OPV can be controlled systematically to achieve specific optoelectronic properties. The process allows the structural modification of attached OPV at a molecular level either by varying the chain length or by changing functionalities. The step-wise generation of OPV chains on the backbone of a highly soluble polymer ensures solubilization in a variety of solvents and also the exhibition of interesting optical properties. [Copyright &y& Elsevier]