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Abstract: The combination of metal nanostructures and pristine graphene with high quality is highly expected for many applications. A method for the large-scale production of metal nanoparticle (NP)/pristine graphene hybrid and its conductive polymer composites is presented, by a combinatorial process of noncovalent functionalization of defect-free pristine-graphene with Poly(amidoamine) (PAMAM) dendrimer and the homogenous attachment of metal NPs on graphene surface. Stable PAMAM functionalized graphene nanofluid is achieved when there is the absence of solvents. The graphene sheets in the hybrid preserve the intrinsic structure and homogenous dispersion. Silver NP (AgNP) decorated graphene hybrid with homogenous dispersion is realized by using PAMAM as stabilizing and also reducing agents through thermal reduction method. The hybrid is used as nanoscale filler to generate epoxy-based conductive composites for electrical interconnects due to the combined effects of the excellent electrical conductivity of high-quality pristine-graphene at low percolation threshold and enhanced contacts between the fillers by low temperature sintering of AgNPs. This method could lead to the large-scale production of graphene-based composites for a wide range of applications. [Copyright &y& Elsevier]

Abstract: 4-Aminobenzoyl-functionalized graphite is produced by the edge-functionalization of pristine graphite with 4-aminobenzoic acid via Friedel–Crafts acylation reaction. The edges of solid functionalized graphite are exfoliated with a high degree. The functionlization predominantly occurs at the edge region of graphite and the structure of pristine graphene in the interior basal planes is retained. The solid functionalized graphite is a promising precursor for the exfoliation into few layer graphene sheets in low boiling point solvents under ultrasonication. The functionalized graphene sheets are employed as nanoscale reinforcement to prepare epoxy-based conductive composite for electrical interconnects. The results show that the electrical conductivity of the composites with addition of 0.6wt% functionalized graphene has an increase of 31.3% and the shear strength of the composites simultaneously improves from 8.7MPa to 15.2MPa. The covalent interactions between graphene and epoxy matrix provided by terminal amino groups can maintain the excellent dispersion of graphene in the matrix, leading to a 3D network. The graphene sheets come in contact with microscale silver fillers, constructing effective electrical bridges between the fillers. The increased flexibility of epoxy network leads to the reinforcement of shear strength. This technique extends the application of graphene in the conductive composites for electrical interconnects. [Copyright &y& Elsevier]