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Information × Registration Number 0214U002502, 0113U001532 , R & D reports Title Epoxy-metal-oxide composites obtained via the sol-gel method and protective coatings on their base. popup.stage_title Head Mykhalchuk Volodymyr Mykhajlovych, Registration Date 13-01-2014 Organization Donetsk National University popup.description2 Object of investigation - epoxy-silica composites synthesized via the sol-gel technology using anhydride curing or cationic polymerization of epoxy. The goal is establishment of regularities of aggregative-stable systems formation at all stages of composite materials obtaining, and structural and morphological features of the synthesized composites depending on the composition, the sol formation conditions and method of epoxy matrix curing. Methods - scanning electron microscopy, transmission electron microscopy, photocolorimetry, small angle X-ray scattering, chemical analysis, gravimetry, thermomechanical and differential thermomechanical analysis, IR spectroscopy, viscosymetry. Methods of aggregative and sedymentative stable compositions obtaining and synthesis of structurally homogeneous epoxy-silica composites of anhydride curing containing 0.5-3.0 wt% of silica particles (SP) and nanocomposites of cationic polymerization of hot and cold curing (SP contants is 10 wt%) utilizing sol-gel method were developed. The relationsheep between composition and conditions of epoxy-silica composites formation and their structural and morphological features was established. It was shown that during the synthesis fractal structures consisting of primary silica particles with the size of 4-10 nm are formed in the polymeric matrix. As siloxane component content in the polymer matrix increases consolidation of SP take place. Sol formation in the absence of epoxy resin leads to larger particles formation due to the deepening of hydrolytic polycondensation ethoxysylanes. At filler concentration of 1.5 wt% in the composite the spatial cluster of silica nanoparticles is formed. Sol formation conducted in the absence of epoxy oligomer was observed spatial periodicity in SP arrangement in epoxy matrix. It was shown that the size of silica particles in the composites of cationic polymerization with the filler content 1 wt % varies from 80-120 nm to 400 nm. They possess defective structure and form a transition layer at the boundary with the polymeric matrix. Nature of particles was confirmed by the results of X-ray elemental analysis. It was stablished that unmodified epoxy polymers and composites possess microglobularic structure. The results of investigation can be proposed for development of novel polymer materials at the 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 Лига Рита Іванівна Лугова Ганна Олександрівна Михальчук Володимир Михайлович popup.nrat_date 2020-04-02 Close