Multifunctional coatings based on GNP/epoxy systems: Strain sensing mechanisms and Joule's heating capabilities for de-icing applications

Abstract

Multifunctional coatings based on a GNP/epoxy system have been manufactured and their strain sensing and Joule’s heating capabilities for anti-icing and de-icing applications have been explored. It has been observed that an increase in the GNP content induces a detriment on the gauge factor (from 5.75 at 8% to 2.49 at 12%) due to a lower interparticle distance between nanoparticles, being less sensitive. However, in any case, the GF values at bending conditions are significantly above conventional metallic gauges (which is around 2). On the other hand, the resistive heating is more efficient when increasing the GNP content, as expected, due to a higher number of conducting pathways that allows a more efficient Joule’s heating effect. However, and due to the heterogeneity present at 12% GNP samples due to the much higher viscosity of the mixture during the dispersion process, the 10% ones were selected for a de-icing proof of concept, proving that the ice completely melts after 5 min of applying 200 V. Therefore, the proposed GNP coatings show an outstanding capability for both strain sensing and de-icing purposes by resistive heating, being useful for a wide range of applications.