Mechanically robust, electrically and thermally conductive graphene-based epoxy adhesives

Abstract

This study develops a facile approach to fabricate adhesives consists of epoxy and cost-effective graphene platelets (GnPs). Morphology, mechanical properties, electrical and thermal conductivity, and adhesive toughness of epoxy/GnP nanocomposite were investigated. Significant improvements in mechanical properties of epoxy/GnP nanocomposites were achieved at low GnP loading of merely 0.5 vol%; for example, Young's modulus, fracture toughness (K 1C) and energy release rate (G 1C) increased by 71%, 133% and 190%, respectively compared to neat epoxy. Percolation threshold of electrical conductivity is recorded at 0.58 vol% and thermal conductivity of 2.13 W m À1 K À1 at 6 vol% showing 4 folds enhancements. The lap shear strength of epoxy/ GnP nanocomposite adhesive improved from 10.7 MPa for neat epoxy to 13.57 MPa at 0.375 vol% GnPs. The concluded results are superior to other composites or adhesives at similar fractions of fillers such as single-walled carbon nanotubes, multi-walled carbon nanotubes or graphene oxide. The study promises that GnPs are ideal candidate to achieve multifunctional epoxy adhesives.

A highly flexible, electrically conductive, and mechanically robust graphene/epoxy composite film for its self‐damage detection

“…Graphene has attracted a great attention for fabrication of flexible electronics devices/sensors because of its outstanding properties such as ultra‐high toughness, high elasticity, high electron mobility, and transparency and high electrical conductivity . Compared with CNTs, graphene provide lower cost in fabrication in the epoxy composites . Graphene platelets (GnPs) have been introduced recently with enormous advantages for fabrication of flexible sensors, including great structural sturdiness, high C/O proportion resulting in immensely increased electrical conductivity, offering solid foundation for piezoresistive sensors, and cost‐effectiveness .…”

Synergistic effect of graphene and carbon nanotube on lap shear strength and electrical conductivity of epoxy adhesives

“…However, the strength of the epoxy‐based adhesive joints is low in comparison with bolted, riveted, and welded joints . Developing mechanically robust and electrically and thermally conductive adhesives is of great interest in many industries including electronics, aerospace, and automotive. Mechanical strength, and electrical and thermal properties of epoxy adhesives can be improved by the addition of carbon nanomaterials such as carbon nanotubes (CNTs) and graphene, owing to their excellent mechanical and physical properties, and their high aspect ratio …”

Mixed Carbon Nanomaterial/Epoxy Resin for Electrically Conductive Adhesives

“…They are able to establish a percolation network at low nanoparticle contents, while enhancing the mechanical properties [7]. Meng et al [8] reached electrical percolation for epoxy/graphite nanoplatelets (GnP) at approximately 1.2 wt.% GnP, reaching a maximum electrical conductivity of 10 −3 S/m and thermal conductivity of 0.33 W/m•K at approximately 4 wt.% of GnP. Li et al reported a percolation threshold of 1.2 wt.% for epoxy/functionalized graphene composites [9].…”