Electromagnetic properties of graphene nanoplatelets/epoxy composites. (18th May 2016)

• Record Type: Journal Article
• Authors: Plyushch, A.; Macutkevic, J.; Kuzhir, P.; Banys, J.; Bychanok, Dz.; Lambin, Ph.; Bistarelli, S.; Cataldo, A.; Micciulla, F.; Bellucci, S.
• Is Part Of: Composites science and technology. Volume 128(2016)
• Page Start: 75
• Page End: 83
• Publication Date: 2016-05-18
• Subjects: Polymer-matrix composites (PMCs) -- Nano particles -- Electrical properties -- Thermal properties -- Annealing; Composite materials -- Periodicals; Composite materials; Fibrous composites; Periodicals; 620.118
• DOI: 10.1016/j.compscitech.2016.03.023
• Languages: English
• ISSNs: 0266-3538

Abstract

Abstract: Results of broadband dielectric spectroscopy of epoxy resin composites containing graphene nanoplatelets (GNP) are presented in a wide temperature range (25–500 K). The as-produced composites were heated at temperatures above the epoxy glass transition and subsequently cooled down to room temperature. This annealing was proved to be a simple but powerful process to improve significantly the electromagnetic properties of the GNP-based composites. The dc conductivity of epoxy filled with 4 wt% GNP is 68 times higher after annealing. Another benefit of the annealing is to lower substantially the percolation threshold, from 2.3 wt% for as-produced samples to 1.4 wt%. In composites above the percolation threshold, the electrical conductivity is the result of tunneling between GNP clusters. For a given GNP concentration, the tunnel barrier decreases after annealing.