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Preprint (submitted version) of the article:Molecular Engineering of MnII Diamine Diketonate Precursors for the Vapor Deposition of Manganese Oxide Nanostructuresby:C. Maccato, L. Bigiani, G. Carraro, A. Gasparotto, R. Seraglia, J. Kim, A. Devi, G. Tabacchi, E. Fois, G. Pace, V. Di Noto, D. Barreca, To be cited as:Chem. Eur. J. 2017, 23, 17954-17963DOI: 10.1002/chem.201703423supporting data are available at the links below

Polybenzimidazoles (PBIs) are among the polymers of choice to prepare membranes for high temperature polymer fuel cells. Poly-2,2′(2,6-pyridine) -5,5′-bibenzimidazole (PBI5N), doped with H3PO4, and acid-doped PBI5N containing 10 wt% of imidazole-functionalized silica membranes were studied with thermogravimetric analysis, differential scanning calorimetry, dynamic-mechanical analysis, infrared spectroscopy, and broadband electric spectroscopy to examine the structure-property relationships. Key results show that: (1) doped PBI5N membranes show thermal decomposition starting at 120 °C, while pristine PBI5N is stable up to 300 °C; (2) the presence of filler increases the acid uptake and decreases the crystallinity of PBI5N; (3) the addition of phosphoric acid reduces the mechanical properties of the membrane, while the addition of filler has the opposite effect; (4) acid-doped membranes have conductivity values on the order of 10 -2-10-3 S cm-1; and (5) membranes exhibit a Vogel-Tamman-Fulcher (VTF) type proton conduction mechanism, where proton hopping is coupled with the segmental motion of the polymer chain. Infrared spectroscopy combined with DFT quantum mechanical calculations was used to assign the experimental spectrum of PBI5N

Hyper-cross-linked resins stemming from a gel-type poly-chloromethylated poly(styrene-co-divinylbenzene) resin (GT) have been investigated by a multi-methodological approach based on elemental analysis, scanning electron microscopy, X-ray microanalysis, and solvent absorption. The hyper-cross-linking of the parent resin was accomplished by Friedel-Crafts alkylation of the phenyl rings of the resins with the chloromethyl groups. This produced a permanent pore system comprising both micropores (

The current state of the art of polymer electrolytes for application in low-temperature fuel cells consists in perfluorinated ionomers such as Nafion®, Aquivion®, Aciplex® and others. In these materials, the fluorocarbon backbone chain is functionalized by perfluoroetheral chains tipped with acid -SO3H groups. The resulting systems are characterized by a very good proton conductivity and an excellent chemical and electrochemical stability. However, perfluorinated ionomers have a series of important drawbacks, including: (a) a relatively high permeability to reagents; (b) a very high production cost; (c) the necessity of a high hydration degree to conduct protons efficiently; and (d) the difficulty to operate at temperatures higher than 80-90°C. In order to overcome these problems, one solution is to replace the perfluorinated ionomers with other proton-conducting electrolytes. Two of the most promising systems are: (a) sulphonated polyaromatic membranes such as sulfonated polyetherether ketone (SPEEK); and (b) polybenzimidazole (PBI)-based systems doped with a mineral acid such as H3PO4 or H2SO4. SPEEK is cheap, its sulfonation degree (DS) can be controlled easily during the preparation of the material and has a very low permeability to the reagents. For these reasons, SPEEK is particularly suitable for applications in fuel cell systems fed with alcohols. On the other hand, PBI-based systems doped with mineral acids are known to conduct protons in anhydrous conditions up to a very high temperature (T ? 250-280°C). Thus, several fundamental and technological problems arising during the engineering of the final fuel cell power plant can be successfully solved. In this work, the electric properties of a few representatives of both families of protonconducting polymer electrolytes are investigated in detail. In particular, it is studied the effect of increasing DS on the electric properties of SPEEK, and how the conductivity of poly-2,2'(2,6-pyridine)-5,5'-bibenzimidazole (PBI5N) is affected by doping with H3PO4 and 10wt% of imidazole-functionalized silica. The electric properties of the materials are investigated by broadband electric spectroscopy (BES) in the frequency and temperature ranges of 10-2 Hz to 10 MHz and 5 to 155°C, respectively. The analysis of the real and imaginary components of the electric conductivity and permittivity spectra allows to rationalize the mechanism of proton conduction in terms ofrelaxation events and multiple interfacial polarization events. The comparison of all the results determined on both families of materials allows to study the interplay between the chemical composition of the materials and their electrical properties, also evidencing the presence of multiple phases in the investigated systems.

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Four platinum(II) complexes of general formula [PtCl(g1-C9H7)L2] [where L2 is 1,2-bis(diphenylphosphino) ethane (dppe) 1 or cycloocta-1,5-diene (cod) 3] and [PtCl2L2] (where L2 is dppe 2 or cod 4) were studied. Inhibition growth assays on human tumor cell lines evidenced for 1 and 3 an antiproliferative effect and, interestingly, the cytotoxic effect exerted by 1 is similar to that of cisplatin. Electrochemical and NMR measurements allowed us to determine the structural and redox properties. Investigation of the mechanism of action responsible for the cytotoxicity demonstrated a weak capacity of interacting with DNA. Some experiments performed on rat liver mitochondria indicate that 1 acts as an inducer of the mitochondrial permeability transition, thus leading to the release of proapoptotic factors, such as cytochrome c and apoptosis-inducing factor

The present paper reports a quantitative investigation on the binding of aluminum to human serum albumin. Equilibrium dialysis and a general thermodyanamic approach have been used to determine the binding parameters. Two aluminum binding sites have been identified on the albumin molecule, involving sites with single or double occupancy models. The binding properties of these two distinct sites appear to undergo reciprocal influences, suggesting a possible interaction between the corresponding protein moieties. Both coordination modes proceed from weak interactions, as shown by the binding energies calculated.

The presence of inorganic moieties in polymers greatly expands the range of their properties and applications and at the same time overcomes some of the disadvantages of conventional polymer chemistry, such as low temperature hardness and brittleness, photochemical instability, or low electric conductivity. In this framework, the cluster Zr4O2(OMe)(12) (OMe = methacrylate) (Zr4), was prepared starting from zirconium butoxide and an excess of methacrylic acid. Inorganic-organic hybrid materials were then synthesized by radical-initiated copolymerization of Zr4 and methylmethacrylate in benzene with different molar ratios. Glassy, highly transparent hybrid polymers were obtained. The thermal behavior, the composition and the structure of the polymers were investigated by elemental analysis, thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), infrared spectroscopy (IR), C-13 MAS NMR, X-ray photoelectron spectroscopy (XPS), and inductively coupled plasma atomic emission spectrometry (ICP-AES). The spectroscopic data show that the clusters crosslink the poly(methylmethacrylate) (PMMA) chains and that the oxometallate complexes are completely incorporated into the hybrid materials. Compared with the undoped polymer, the hybrid polymers have enhanced thermal properties and a characteristic dielectric behavior.

Radical polymerization of methyl methacrylate with 0.5-2 mol% of the (meth)acrylate-substituted oxozirconium and oxotitanium clusters Zr-6(OH)(4)O-4(OMc)(12) (OMc = methacrylate), Zr4O2(OMc)12, Ti6O4(OEt)(8)(OMc)(8) and Ti4O2(OPri)(6)(OAcr)(6) (OAcr = acrylate) results in an efficient cross-linking of the organic polymers, The obtained inorganic-organic hybrid polymers exhibit a higher thermal stability due to inhibited depolymerization reactions. Contrary to undoped poly(methyl methacrylate), the cluster cross-link-ed polymers are insoluble but swell in organic solvents. The solvent uptake upon swelling decreases with an increasing amount of polymerized cluster. The impedance spectra of PMMA doped with various proportions of Zr4O2(OMc)12 show that the capacitance of the polymers decreases with an increasing proportion of the cluster. The polymer doped with 2 mol% of Zr4O2(OMc)12 shows an increase in conductivity to 0.9(.)10(-7) S(.)cm(-1) at 74 degreesC