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11.
D.H. Kim J.H. Moon D.W. Lee Y.G. Shul 《Journal of Sol-Gel Science and Technology》2003,26(1-3):403-406
The acid catalyzed sol-gel reaction in the mixed binder system, 3-glycidoxypropyltrimethoxysilane (GPTS)/3-aminopropyltriethoxysilane (APTS) was investigated and one step and two step synthesis process were compared. Hydrolysis product was observed using the 1H, 13C NMR and Raman spectra. Especially, based on the Raman spectra, epoxy ring opening was observed, varying the ratio of GPTS to APTS. The two step process made clear sol, while the one step process resulted in a milky suspension. According to the Raman spectra, the epoxy ring opening reaction kinetics proceeded slower in the two step process than one step process. Throughout the two step process, it was possible to apply the binder for the coating of substrate. 相似文献
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The influence of humidity on the conductivity of graphite oxide (GO) films has been considered. Graphite oxide films of a 200–500 nm thickness become conductors to have a conductivity of 10?6 to 10?2 S/cm when humidity increases from 30 to 100%. Film morphology varies during the course of water diffusion. Ultraviolet light-mediated reduction of GO decreases the sensitivity to humidity until its complete disappearance. 相似文献
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Yu. M. Shul’ga V. N. Vasilets S. A. Baskakov M. A. Smirnov V. P. Tarasov V. I. Volkov G. A. Kichigina P. P. Kushch D. P. Kiryukhin 《High Energy Chemistry》2013,47(6):291-294
By solid-state magic angle-spinning nuclear magnetic resonance spectroscopy (NMR), differential scanning calorimetry (DSC), and IR spectroscopy, polytetrafluoroethylene (PTFE) samples obtained by low-temperature (T = ?196°C) postradiation polymerization of tetrafluoroethylene (C2F4) and C2F4 mixtures with a 3D graphene material formed by the microwave exfoliation of graphite oxide films (MEGO) have been investigated. It has been shown that the melting point of PTFE in the PTFE-MEGO composite is 332.5°C, which is 8.8°C above the melting point of pure PTFE obtained under the same conditions. According to the measured values of specific enthalpy of melting ΔH m (51.5 and 45.4 J/g), the degrees crystallinity (x c) of 0.63 and 0.55 have been calculated for the pure polymer and the composite, respectively. It has been also found that none of the PTFE-containing samples examined has terminal CF3 groups typical of PTFE prepared by conventional suspension polymerization. 相似文献
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Experimental approaches for evaluation of reactivity of phosphate raw material and obtaining additional information on its phase composition were suggested in view of physicochemical patterns of the phosphate raw material decomposition in a weakly acidic environment. 相似文献