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Information × Registration Number 0212U002633, 0110U003467 , R & D reports Title Sol-gel synthesis of epoxy-siloxane composites and their resistance to thermooxidative destruction popup.stage_title Head Mykhalchuk Volodymyr Mykhajlovych, Registration Date 16-01-2012 Organization Donetsk National University popup.description2 Object of investigation - epoxy-silica nanocomposites synthesized via the sol-gel technology using anhydride curing or cationic polymerization of epoxy. The goal of the current stage of research is investigation of structure of epoxy-silica nanocomposites cured with anhydride or by cationic polymerization. Methods used - scanning electron microscopy, transmission electron microscopy, small-angle x-ray scattering, thermal mechanical analysis. Using the sol-gel method epoxy-silica nanocomposites of anhydride curing or cationic polymerization with silica content 0.5-10 wt.% were obtained. It was found that during the synthesis in polymer matrix of composites cured with acid anhydride fractal-type structure constructed from primary silica particles was formed. At silica concentration 1.5 wt.% the spatial cluster of silica particles was formed. If the silica sols were obtained in the absence of epoxy oligomer the silica particles were spatially regularized in composites matrix. It was established on model systems using IR-spectroscopy that kinetic chain transfer side reactions in composites of cationic polymerization can be avoided in two ways: by forming thin coating in order to provide free evaporation of hydroxyl-containing compounds, or by the exposure of liquid composition under vacuum before curing. It was shown by scanning electron microscopy that nanosized silica particles are formed when silica content in the system is 1 wt.%. The results of investigation can be proposed for development of novel polymer materials in Ukrainian state research institute of plastic masses, The Institute of Macromolecular chemistry of the NAS of Ukraine, Antonov ASTC etc. Product Description popup.authors Жильцова Світлана Віталіївна (без оплати) Леонова Наталя Геннадіївна (без оплати) Лига Рита Іванівна Лугова Ганна Олександрівна Михальчук Володимир Михайлович popup.nrat_date 2020-04-02 Close