Thermal conductivity and mechanical properties of epoxy vitrimer nanocomposites reinforced with graphene oxide

Abstract

Novel composite film materials were fabricated by thiol-epoxy click reaction in the presence of ≤ 1 wt.% graphene oxide (GO). SEM, X-ray diffraction, and FTIR techniques were used for comprehensive characterization of the composites' morphology and structure. The grafting of GO into the epoxy vitrimer network was confirmed. The effect of loadings of GO on the mechanical properties of composite films was examined. The tensile strength and Young's modulus of composite material increase by 69 and 46 %, respectively, with the addition of 0.5 wt.% GO. The flexibility of the composite films improved more than fourfold by adding 1.0 wt.% GO compared to the epoxy vitrimer network.The gas-microphone photoacoustic approach was applied for the thermal conductivity evaluation of the samples. The composites showed a maximum increase in thermal conductivity almost two times with the addition of 1.0 wt.% GO as compared to the polymer matrix.

Model Polyisoprene Vitrimers

“…In this regard, Leibler and co-workers discovered a new class of dynamic polymeric thermosets, coined by them vitrimers, using ester DCB (dynamic covalent bonds are reversible chemical bonds with intermediate bond dissociation energy, suitable for exchanges among several molecules) , as cross-links via transesterification reactions . This new class of materials shows unique properties such as self-healing, weldability, and recyclability, which could provide additional features to thermosets such as enhanced lifetime, sustainability, and liveability. , …”

“…7 This new class of materials shows unique properties such as self-healing, weldability, and recyclability, which could provide additional features to thermosets 6 such as enhanced lifetime, sustainability, and liveability. 1,8 Vitrimers are dynamic polymer materials that combine the properties of thermoplastics and thermosets. 9−12 These materials behave like viscoelastic liquids at high temperatures (glass-like fluidity) and show thermosetting behavior at low temperatures.…”