Improved lightning protection of carbon fiber reinforced polymer wind turbine blades: Epoxy/graphene oxide nanocomposites

Nanodielectric composites belong to a type of materials engineered for improved performance in several different fields. Advanced technology devices require a new class of materials, combining suitable electrical and thermal properties, as well as, mechanical performance and easy processing. In nanocomposites, a key parameter is the interaction between the matrix and the nanofiller. In the present work, the effect of filler load of graphene oxide (GO), on the thermal and electrical response of epoxy-based nanocomposites was investigated. The final goal of the project is to develop epoxy nanocomposite systems which will meet the requirements to be utilized as a matrix, in carbon fiber reinforced polymer (CFRP) wind turbine blades with improved lightning protection performance. It was found that a filler load of 3 wt% leads to percolation threshold. The dielectric spectroscopy results confirm the percolation and also show inert dipoles with increasing filler load. The high filler load leads also to lower impulse breakdown strength. The thermal response is affected by the oxygen-based groups of the GO. It was also found that the dispersion/exfoliation method used affects the response of the epoxy resin.