A new thermally conductive thermoset composite has been developed. A hybrid organic-inorganic material composed of an epoxy resin crosslinked with a flexible diamine hardener, and a BN, was prepared by incorporating e...A new thermally conductive thermoset composite has been developed. A hybrid organic-inorganic material composed of an epoxy resin crosslinked with a flexible diamine hardener, and a BN, was prepared by incorporating epoxy structure units covalently into a BN via the sol-gel approach. The precursor was obtained by the reaction of DGEBA （diglycidyl ether of bisphenol A） with TEOS （tetraethyl orthosilicate）. The precursor was then hydrolyzed and co-condensated with tetraethyl orthosilicate which is covalently bond with the hydroxyl groups on the BN surface at room temperature to yield epoxy-BN hybrid sol-gel material. FTIR spectroscopy confirmed the formation of organic and inorganic network. The thermal conductivity as measured by thermal conductive analyzer showed an increase up to 0.4048 W/m.K, for a mixture containing 0.4 wt% of BN fillers in the epoxy matrix. Moreover, the optimum conditions for surface modification of BN particle were also investigated.展开更多
A kind of modified epoxy resins was obtained by condensation of epoxy resin with silicic acid tetraethyl ester（TEOS） and nano-SiO2. The reactions were performed with hydrochloric acid as a catalyst at 63 ℃. The str...A kind of modified epoxy resins was obtained by condensation of epoxy resin with silicic acid tetraethyl ester（TEOS） and nano-SiO2. The reactions were performed with hydrochloric acid as a catalyst at 63 ℃. The structure, thermal stability and morphological characteristics of the modified epoxy resins were studied through infrared spectra（FT-IR） analysis, thermogravimetric（TG） analysis and scanning electron microscopy respectively. It has been found from the IR and TG study that modified epoxy resins have greater thermal stability than epoxy resins, and its thermal stability has been improved by the formation of inter-crosslinked network structure. The modified epoxy resins exhibit heterogeneous morphology and heterogeneity increases with more TEOS feeding, which in turn confirms the formation of inter-crosslinked network structure in modified epoxy resins.展开更多
文摘A new thermally conductive thermoset composite has been developed. A hybrid organic-inorganic material composed of an epoxy resin crosslinked with a flexible diamine hardener, and a BN, was prepared by incorporating epoxy structure units covalently into a BN via the sol-gel approach. The precursor was obtained by the reaction of DGEBA （diglycidyl ether of bisphenol A） with TEOS （tetraethyl orthosilicate）. The precursor was then hydrolyzed and co-condensated with tetraethyl orthosilicate which is covalently bond with the hydroxyl groups on the BN surface at room temperature to yield epoxy-BN hybrid sol-gel material. FTIR spectroscopy confirmed the formation of organic and inorganic network. The thermal conductivity as measured by thermal conductive analyzer showed an increase up to 0.4048 W/m.K, for a mixture containing 0.4 wt% of BN fillers in the epoxy matrix. Moreover, the optimum conditions for surface modification of BN particle were also investigated.
文摘A kind of modified epoxy resins was obtained by condensation of epoxy resin with silicic acid tetraethyl ester（TEOS） and nano-SiO2. The reactions were performed with hydrochloric acid as a catalyst at 63 ℃. The structure, thermal stability and morphological characteristics of the modified epoxy resins were studied through infrared spectra（FT-IR） analysis, thermogravimetric（TG） analysis and scanning electron microscopy respectively. It has been found from the IR and TG study that modified epoxy resins have greater thermal stability than epoxy resins, and its thermal stability has been improved by the formation of inter-crosslinked network structure. The modified epoxy resins exhibit heterogeneous morphology and heterogeneity increases with more TEOS feeding, which in turn confirms the formation of inter-crosslinked network structure in modified epoxy resins.
