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The rapid progress in miniaturization and integration of semiconductor power devices has made heat dissipation a critical concern in the development of high‐performance semiconductor devices, thereby increasing the demands for the heat transfer efficiency of polymer composites. To address this issue, an efficient three‐dimensional (3D) heat conduction network structure is constructed in the polymer matrix by leveraging the mutual reaction of amino and epoxy groups on the surface of the filler treated by coupling during the melt mixing process, this approach leads to an enhancement in the thermal conductivity of the composites. First, the inert surfaces of graphene nanosheets (EX‐G) and carbon fibers (CF) are coated with polydopamine (PDA) to form active sites. Subsequently, the graphene (EX‐G), alumina (Al2O3), and carbon fiber (CF) are treated with an amine coupling agent (KH550) and epoxy coupling agent (KH560), respectively. Notably, at a filler content of 25 wt%, the thermal conductivity (TC) of the composites increases by approximately 282% compared to pure nylon 6. This research contributes novel insights into the field of thermally conductive polymer composites. Highlights: The surface of the EX‐G and CF covered by PDA generates active sites.Fillers reduce the interface thermal resistance through chemical bonds.Fillers surface reaction builds a 3D thermal conductive network.3D network structure can significantly improve the TC of composites.Only 25 wt% of hybrid fillers in a 282% increased TC of composites. [ABSTRACT FROM AUTHOR]

Ethylene‐vinyl acetate copolymer (EVA) has been widely used for packaging materials for decades. However, EVA was highly restricted due to the poor thermal stability and anti‐static performance. For enhancing thermal stability and anti‐static performances, a large number of additives were added to EVA, which seriously prejudice the processability and mechanical properties of the polymer. To address this problem, N‐doped reduced graphene oxide@Fe2O3 (RGF) was constructed as a heat and electronic conduction actor in EVA matrix in this work. As as‐prepared RGF composites shown, Fe2O3 particles well dispersed on the surface of RGO sheets, forming a point‐plane three‐dimensional structure. Therefore, the thermal conductivity and volume resistivity of the EVA composites reached 0.58 W/mK and 1.7 × 1010 ohm∙cm at 1.0 wt.% of RGF addition, which shows 284% folds increasement and 7 orders of magnitude decrement than neat EVA. Moreover, the storage modulus and thermal stability of EVA composites at 180°C were also improved. In sum, all those enhancements were attributed to the Fe2O3 particles well dispersed on RGO sheets, and amino groups from RGF provided mass of hydrogen bonds with EVA chains which provide more sites and path for heat and electronic conduction. In this work, RGF composites and its synthesis strategy show potential promising in the highly effective thermal and electrical exchange materials. [ABSTRACT FROM AUTHOR]

Polyaniline/MnO2/graphite felt (PMGF) composite, which can be used as a novel free-standing, flexible electrode for supercapacitors, was fabricated via a facile electrochemical method. Polyaniline/graphite felt (PANI/GF) electrode was prepared by electropolymerization of PANI onto the GF. Subsequently, manganese dioxide (MnO2) was electrodeposited on the surface of the PANI/GF electrode to prepare PMGF electrode. The microstructure and morphology of the as-prepared samples were characterized by Fourier transform infrared spectra, X-ray diffraction, scanning electron microscopy, and transmission electron microscopy. Specific surface area was examined using N2 adsorption/desorption test. Cyclic voltammogram, chronopotentiometry techniques and electrochemical impedance spectroscopy were introduced to investigate the electrochemical performance of the composites. The PMGF electrode exhibited specific capacitance as high as about 630 F g−1 at the current density of 0.5 A g−1, which is much higher than that of PANI/MnO2 composites reported previously. The high specific capacitance of PMGF may be attributed to the fact that the porous GF is a good conductive matrix for the dispersion of PANI/MnO2 and it can facilitate easy access of electrolytes to the electrode, which results in enhancement of the electrochemical performance of the composite. Moreover, the specific capacitance of PMGF is much larger than that of MnO2/GF (MGF), which may be ascribed to the participant of PANI, which contributes additional pseudocapacitance and electron transport path. POLYM. COMPOS., 34:819-824, 2013. © 2013 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

A novel conjugated polymer containing electron transport groups with high electron affinity, denoted POXD was synthesized upon polycondensation. The polymer was characterized by Fourier transform infrared (FTIR) spectra and 1H nuclear magnetic resonance (1H NMR) spectroscopy. Furthermore, the conjugated polymer/graphene (POXD/RGO) composite film was prepared, which was subsequently used as the support for the electrodeposition of platinum. The microstructure and morphology of the prepared samples were characterized by X-ray photoelectron spectroscopy (XPS) and field emission scanning electron microscopy (FE-SEM). The electrocatalytic activity for the oxidation of methanol was investigated through cyclic voltammogram method. The POXD/RGO composite film can facilitate the electrodeposition of Pt nanoparticles compared with graphene (RGO) support. The POXD/RGO/Pt composite exhibits more excellent electrocatalytic property for the oxidation of methanol, such as lower oxidation potential and higher current intensity, which might be attributed to the high electron affinity of the polymer and the interaction of the Pt nanoparticles with polymer. POLYM. COMPOS., 2012. © 2012 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]