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Carbon-based nanomaterials have captured significant interest in academics for decades. Recently, graphene has been found to be a promising nanomaterial. In this study, novel functionalized graphene oxide nanoflakes (FGONs) were successfully synthesized using silane coupling agents via a chemical approach and used as a reinforcement in cyanate ester (CE)/bismaleimide (BMI) copolymers. The curing mechanism and thermal properties of the FGONs/CE/BMI nanocomposites were investigated by Fourier transform infrared spectroscopy, differential scanning calorimetry, and thermogravimetry. The results show that the addition of FGONs not only catalyzed the entire curing process but also increased the thermal stability of the nanocomposites. The flexural and impact strengths reached optimum values of 110 MPa and 10.98 kJ m−2 with a load of 1.0 wt% FGONs, respectively. Moreover, the glass transition temperature and dielectric properties of the nanocomposites were lower than those of the CE/BMI copolymer. [ABSTRACT FROM AUTHOR]

Abstract: Polypyrrole-coated hollow Zn2SnO4 boxes (hollow Zn2SnO4@PPY nanocomposites) had been prepared by a microemulsion polymerization. The structural, morphological and electrochemical properties were methodically investigated by means of XRD, TGA, BJH (pore size distribution analysis), SEM, TEM, and electrochemical measurements. Results show that the hollow Zn2SnO4 boxes with the uniform and cube like structure are coated by PPY. Electrochemical measurement suggests that hollow Zn2SnO4@PPY composites exhibit better cycling properties and lower initial irreversible capacities as anode materials for lithium-ion batteries. At a current density of 60mA/g in the voltage about 0.01–3.0V, the first discharge–charge capacities of hollow Zn2SnO4@PPY composites are 1105.2mAh/g and 556mAh/g. After 50 cycles, a specific charge capacity of 478.4mAh/g remained and the coulombic efficiency reaches 98.2%, revealing better capacity retention compared with hollow Zn2SnO4 boxes. [Copyright &y& Elsevier]