| Carbon nanomaterials have been a hot research in materials science,the discovery of graphene caused an interests of researchers.Graphene is widely used in microwave absorption,lithium battery,solar cells,polymer composites,catalyst and sensor,et al.,due to its excellent physical and chemical performance.Graphene filled in polymers is an important direction in numerous research fields.However,graphene is hard to disperse evenly in polymer and is prone to reunite due to the size effect of graphene,which affects the performance of polymer composites.Therefore,the graphene material modification has become a hot research focus.The purpose of this paper is to prepare a kind of silane coupling agent(KH-560)to modify graphene and synthesis a graphene-zinc oxide micro-sphere binary composites.With cyanate ester resin as a polymer matrix and the functional graphene and the graphene-zinc oxide micro-sphere compound filled in the matrix via a solution blending method,the mechanical properties,dielectric properties and thermal stability properties of functionalized graphene/cyanate resin composites are investigated.Based on the topic,the main research contents and research results of this paper are as follows:1.In this thesis the preparation procedure of functionalized graphene/cyanate ester(FGNs/CE)composite was prepared and the integrated properties of the FGNs/CE composite were investigated.The structure and elements composition of silane coupling agent modified graphene and the mechanical properties,thermal stability properties of the FGNs/CE composite were analysed.It showed that the cured temperature of FGNs/CE composite decreased with the increase of functionalized graphene(FGNs)content in the whole curing process due to the FGNs as a catalyst in the FGNs/CE composite.Compared to the virgin cyanate ester resin,the Tmax,Tc and crystallinity of the FGNs/CE composite were decreased.When the content of FGNs was 3 wt.%,the mechanical properties of the FGNs/CE composite achieved the best and the thermal stability of the FGNs/CE composite increased as well.2.The preparation and comprehensive properties of functionalized graphene(FGNs)and functionalized graphene oxide(FGONs)filled in cyanate ester/epoxy copolymer matrix were investigated.The content of FGNs on the effect on the integrated properties of functionalized graphene/cyanate ester/epoxy(FGNs/CE/EP)composites was analysised.When the content of FGNs was 2.0 wt.%,the flexural and impact strength of FGNs/CE/EP composites achieved the best,were 170.8 MPa and 15.5kJ/m~2,respectively,the dielectric and thermal properties of FGNs/CE/EP composites were improved.We also discussed different content of epoxy resin on the effect of functionalized graphene oxide/cyanate ester/epoxy FGONs/CE/EP composites,founding that the mechanical properties of FGONs/CE/EP composites enhanced by introducing epoxy resin,the impact and flexural strength were 1.41 times and 1.72times compared to the virgin cyanate ester resin,respectively.When the content of epoxy resin was 40 wt.%,the storage modulus of FGONs/CE/EP composites was minimum.Compared to the virgin CE resin,the glass transition temperature(Tg)and thermal stability of FGONs/CE/EP composites were decreased.3.The preparation and comprehensive properties of functionalized graphene oxide/cyanate ester/bismaleimide(FGONs/CE/BMI)composites and graphene-zinc oxide/cyanate ester/bismaleimide(RGO-ZnO/CE/BMI)composites were studied.We analysed the structure and phase composition of graphene-zinc oxide(RGO-ZnO)compound and morphology,mechanical properties and thermal stability of FGONs/CE/BMI and RGO-ZnO/CE/BMI composites,founding that the introduction of FGONs improved the mechanical properties of FGONs/CE/BMI composites,when the content of FGONs was 1.0 wt.%,the flexural and impact strengths of FGONs/CE/BMI composite reached 110 MPa and 10.98 kJ/m~2,respectively.Compared to the pure CE resin,the dielectric properties of FGONs/CE/BMI composite were low.The thermal stability of FGONs/CE/BMI composite was good with the content of FGONs increased.When the content of RGO-ZnO was 1.0 wt.%,the flexural and impact strengths of RGO-Zn O/CE/BMI composite reached the optimum values,which were 110 MPa and 10.98 kJ/m~2,respectively.However,high content of RGO-ZnO compound was easy to aggregate in RGO-Zn O/CE/BMI composite.Compared to CE/BMI copolymer,the thermal stability of RGO-ZnO/CE/BMI composite was good.4.High volume content of multiwalled carbon nanotube(MWCNTs),functionalized graphene(GNs)and boron nitride(hBN)particles filled in cyanate ester resin matrix were prepared,the thermal conductivity,electrical conductivity and thermal properties of CE/MWCNTs?CE/GNs?CE/MWCNTs/GNs?hBN/CE and GNs/hBN/CE were investigated.It showed that the thermal conductivity of synergy effect of MWCNTs and GNs?GNs and hBN on CE/MWCNTs/GNs and GNs/hBN/CE composites were good than the thermal conductivity of single MWCNTs,GNs and hBN filling in cyanate ester resin.As GNs/CE for example,GNs/CE composite has excellent electrical conductivity and thermal stability due to excellent electrical conductivity and heat resistant of GNs.5.High FGNs volume content of FGNs/CE/CF composites was prepared with a presoak method and the thermal conductivity,electrical conductivity,mechanical and thermal properties of FGNs/CE/CF composites were investigated.The flexural strength and interlaminar shear strength(ILSS)rose in the first stage,and then decreased with the volume content of FGNs increased.The thermal conductivity of FGNs/CE/CF composite was 5.10 W/m K,the electrical conductivity of FGNs/CE/CF composite in 0°direction improved due to the composition effect between FGNs and CE/CF composites. |
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