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Nana Amponsah Kyeremateng Frederic Dumur Philippe Knauth Brigitte Pecquenard Thierry Djenizian 《Comptes Rendus Chimie》2013,16(1):80-88
The electrochemical synthesis of a copolymer electrolyte (PEO-PMMA) into titania nanotubes is described and studied. Compared with the electrochemical systems based on solid electrolytes deposited by top-down techniques, the copolymer/titania nanotube material reveals high electrochemical performance, opening new perspectives for the fabrication of 3D all-solid-state microbatteries. 相似文献
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Stephen M. June Philippe Bissel Timothy E. Long 《Journal of polymer science. Part A, Polymer chemistry》2012,50(18):3797-3805
Copper(I) catalyzed azide‐alkyne 1,3‐Huisgen cycloaddition reaction afforded the synthesis of triazole‐containing polyesters and segmented block copolyesters at moderate temperatures. Triazole‐containing homopolyesters exhibited significantly increased (~40 °C) glass transition temperatures (Tg) relative to high temperature, melt synthesis of polyesters with analogous structures. Quantitative synthesis of azido‐terminated poly(propylene glycol) (PPG) allowed for the preparation of segmented polyesters, which exhibited increased solubility and mechanical ductility relative to triazole‐containing homopolyesters. Differential scanning calorimetry demonstrated a soft segment (SS) Tg near ?60 °C for the segmented polyesters, consistent with microphase separation. Tensile testing revealed Young's moduli ranging from 7 to 133 MPa as a function of hard segment (HS) content, and stress at break values approached 10 MPa for 50 wt % HS segmented click polyesters. Dynamic mechanical analysis demonstrated an increased rubbery plateau modulus with increased HS content, and the Tg's of both the SS and HS did not vary with composition, confirming microphase separation. Atomic force microscopy also indicated microphase separated and semicrystalline morphologies for the segmented click polyesters. This is the first report detailing the preparation of segmented copolyesters using click chemistry for the formation of ductile membranes with excellent thermomechanical response. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012 相似文献
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Jean-Christophe Loudet Philippe Poulin 《Journal of Dispersion Science and Technology》2013,34(1-3):143-154
We review recent findings about the behavior of emulsions made of droplets suspended in liquid crystalline materials. By contrast to classical emulsions, which are usually made of isotropic oils and water, liquid crystal emulsions exhibit a variety of structures result in the ordering of the continuous phase. The droplets induce the formation of topological defects and distortions that lead to strong and anisotropic elastic forces between the particles. These elastic forces govern the stability and the ordering of the particles. This is observed in aqueous emulsions as well as in non-aqueous emulsions obtained from phase separation phenomena. It is shown that phase separations in liquid crystals can lead to the formation of highly ordered arrays of uniformly sized droplets. More generally, ordered structures seen in liquid crystal emulsions are of interest as examples of topologicallv-controlled organizations; they are also of potential practical importance as a novel way to control both the stability and the structures of colloidal particles. 相似文献
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Hanna Ayoub Virginie LAIR Sophie Griveau Philippe Brunswick Fethi Bedioui Michel Cassir 《Electroanalysis》2012,24(6):1324-1333
An electrochemical sensor detects the risk of diabetes and prediabetes; low potentials are applied to nickel electrodes and electrical responses are measured. Although the contact of nickel with skin is short, the risk of allergical reactions cannot be discarded. SS 304L, with lower Ni content, was tested in carbonate buffer solutions containing chloride, lactate and urea to investigate its sensitivity to different parameters in sweat and compare it to nickel. The results show that SS 304L is a suitable material for the assessment of sudomotor dysfunction due to its high capacity to detect the deviation in Cl? concentration. Sensitivity of SS 304L to Cl? is much higher than for nickel. 相似文献