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In this research project, the hexagonal boron nitride@(silver/copper) (h-BN@(Ag/Cu)) hybrids are successfully synthesized through a jointly decorated two-step process in this work. First, the copper nanoparticles (CuNPs) are decorated on h-BN flakes by reducing copper ions (Cu2+). Subsequently, h-BN@(Ag/Cu) hybrids are fabricated via silver nanoparticles (AgNPs) deposition on the surface of hexagonal boron nitride@copper (h-BN@Cu) flakes. The obtained h-BN@(Ag/Cu) hybrids serve as loading fillers to substantially boost the thermal conductivity of poly(dimethylsiloxane) (PDMS). The thermal conductivity of as-prepared h-BN@(Ag/Cu)/PDMS composite reaches 1.5645 W m−1 K−1 at 25 vol% filler loading. Furthermore, the electrical properties of these composites are comprehensively investigated. Additionally, the mechanism of h-BN@(Ag/Cu) hybrids for thermal conductivity improvement are demonstrated utilizing Fogg's model. This work may provide valuable insight and information for the design and construction of high-performance thermally conductive materials in the future. [Display omitted] [ABSTRACT FROM AUTHOR]

As microelectronic technology advances, electronic devices have become faster and smaller. The electromagnetic radiation has negative effects on electronic device operation, how to eliminate the electromagnetic radiation has attracted much attention. Copper foil is the most commonly used and effective material for reducing electromagnetic radiation. In practical applications, it is necessary to use adhesive to fix it onto the surface of electronic devices. In this work, an integrated electromagnetic shielding material (AgPs/TPU@Cu hybrid film) was designed and prepared by a facile way, in which the mixture of silver particles (AgPs) and thermoplastic polyurethane (TPU) was cured to form a AgPs/TPU composite film on the surface of copper foil (Cu) by a one-pot heating press processing. The horizontal and vertical electrical resistances of AgPs/TPU composite film decreased to 0.2 Ω and 0.47 Ω at the AgPs loading of 38 wt%, respectively, and the corresponding thermal conductivity reached 0.81 W m−1 K−1. Moreover, the AgPs/TPU@Cu hybrid film at the AgPs loading of 38 wt% exhibited the maximum electromagnetic interference shielding effectiveness (EMI SE) value of 105 dB. This work provides valuable information about EMI shielding technologies for practical electronic applications. [ABSTRACT FROM AUTHOR]

With the development of modern science and technology, the coatings with the single function of anti-corrosion have failed to cover the special requirements in various practical applications. Particularly, the good heat dissipation effect of anti-corrosive coatings is highly demanded in some devices like electrical machinery, heat exchanger and printed circuit board. Here, a facile, eco-friendly, low-cost method is developed to fabricate thermally conductive and anti-corrosive composite coatings by mixing fillers (including boron nitride (BN) and graphene nanoplatelet (GNP)), polyvinyl pyrrolidone (PVP) and waterborne epoxy resin (WER). The hybridization of BN and GNP is used to provide more barriers to delay the penetration of corrosive medium and construct a denser heat conduction network in the composite coatings. PVP is selected as the compatibilizer to further improve the anti-corrosion and thermal conductivity of composite coatings. The effects of filler types and contents on the anti-corrosive and thermally conductive properties are researched. At the loading of 30 wt% BN and 0.5 wt% GNP, the BN@GNP/PVP/WER coating reaches the optimizing anti-corrosive ability, where the |Z| value holds around 6.5 × 109 Ω cm2 after soaking in the corrosive medium for 7 days, and the I corr and E corr values are 1.9 × 10−9 A/cm2 and -0.62742 V, respectively. Meanwhile, this coating displays great heat conduction with the thermal conductivity of 0.87 W/mK at about 30 wt% filler loading. Moreover, the electrical properties and hydrophilicity of coatings at different filler formulations are studied. It is worth noting that the higher electrical conductivity of the coatings at higher GNP content may accelerate the corrosion rate. This study provides a simple route for the design and manufacture of highly anti-corrosive and heat-conducting composite coatings, which exhibits great potential application in next-generation electronic packaging and devices. [ABSTRACT FROM AUTHOR]

Polymer composites with electrical insulation and high thermal conductivity are in high demand in the electronics industry. The application potential of electronics material mainly depends on its mechanical properties. In this work, the silver nanoparticles (AgNPs) modified siloxane/graphene nanoplatelet core-shell hybrid (Ag@SiO/GNP) is synthesized through a two-step process. First, hydrolysis-condensation of TEOS and MPS is performed on the surface of pre-treated GNP. Subsequently, AgNPs are decorated on SiO/GNP core-shell hybrids to obtain Ag@SiO/GNP core-shell hybrid. The as-prepared hybrids serve as fillers of epoxy resin (EPR) to prepare Ag@SiO/GNP/EPR composite with high thermal conductivity (1.03W·m−1·K−1, which is 457.2% higher than pure EPR) and good electrical insulation (>1010Ω) at 1 wt% fillers loading. The hydrolysis-condensation of TEOS and saline coupling agent can decline the electrical conductivity of carbon-based materials efficiently, otherwise, the core-shell hybrids can be modified further based on the existing functional groups. The Ag@SiO/GNP/EPR composites exhibit excellent mechanical properties. The mechanism for thermal conductivity improvement of the composites prepared with these core-shell hybrids is demonstrated in detail. [ABSTRACT FROM AUTHOR]

In this work, a new kind of double layers modified alumina-based hybrid (silver@copper@alumina (Ag@Cu@Al 2 O 3) hybrid) was successfully synthesized through the two-step layer-by-layer process. First, copper (Cu) nanoparticles were assembled onto alumina (Al 2 O 3) particles by reduction of Cu2+. Second, Ag@Cu@Al 2 O 3 hybrids were assembled via Ag deposition on the surface of Cu@Al 2 O 3 particles. The obtained Ag@Cu@Al 2 O 3 hybrids served as thermally conductive fillers to greatly boost the thermal conductivity of poly (dimethylsiloxane) (PDMS). The thermal conductivity reached 1.465 W m−1 K−1 at 85 wt% filler loading. The thermal conductivity of PDMS matrix was increased more than 7 times by the addition of Ag@Cu@Al 2 O 3 hybrid, which was much higher than single layer modified alumina-based hybrids (Ag@Al 2 O 3 and Cu@Al 2 O 3 hybrids) and virgin Al 2 O 3 particle. The effect of double layers modified filler, single layer modified filler and virgin filler on the thermal conductivity of PDMS matrix was discussed in detail and the mechanism of these fillers for improving thermal conductivity was studied through Foygel's thermal conduction model. Otherwise, electric, mechanical and thermal properties of Ag@Cu@Al 2 O 3 /PDMS composites were also further tested and analyzed. [ABSTRACT FROM AUTHOR]

A battery of siloxane (SiO)/multi-walled carbon nanotube (MWCT) core-shell hybrids are successfully fabricated by encapsulating MWCTs with siloxanes via the hydrolysis-condensation reaction. First, MWCT is treated by the surfactant to improve the surface polarity. Then, the hydrolysis-condensation reaction of tetraethoxysilane (TEOS) and different saline coupling agents is performed on the surface of MWCTs to achieve various core-shell hybrids. These hybrids serve as fillers of epoxy resin (EPR) to prepare high-performance thermally conductive, electrically insulating and strength-enhanced composites at low fillers loadings. The SiO/MWCT/EPR composite possesses high thermal conductivity (0.55 W m−1 K−1, which is 196.7% higher than pure EPR) and excellent electrical insulation (>1012 Ω) at 1 wt% filler loading. The thermal conductivity improvement mechanism for these composites containing SiO/MWCT core-shell hybrids is demonstrated in detail. Moreover, the siloxane encapsulation route for MWCTs significantly declines their electrical conductivity, which greatly upgrades the practical value of as-prepared thermal conductivity composites. [Display omitted] • Siloxane/carbon nanotube core-shell hybrid is successfully fabricated via the hydrolysis-condensation reaction. • The EPR composites with SiO/MWCT core-shell hybrid fillers possess high thermal conductivity (0.55 W m−1 K−1). • The EPR/SiO/MWCT composite shows excellent electrical insulation (>1012 Ω) at 1 wt% filler loading. • This research provides a practical avenue for producing conductive and electrically insulating materials. [ABSTRACT FROM AUTHOR]