In the last few decades, the development of structural health monitoring systems has attracted the interest of industry. Strain sensors based on carbon nanoparticles, such as carbon nanotubes, are increasingly being thought of as a realistic alternative to conventional sensors based on metallic and semiconducting materials, largely due to their superior electrical properties. The addition of carbon fillers to polymer matrices allows the formation of an electrical network that gives the material a high piezoresistivity. These doped polymer matrices can be manufactured in different forms, such as flexible sensors that can be attached on a substrate, conductive adhesives that can detect crack propagation along bonded joints, etc. Another possibility is to use these matrices in fiber-reinforced polymers for the detection of failure. In this case, the incorporation of carbon nanofiller could also be used in the creation of a coating on traditional fiber fabrics for strain/damage monitoring of the composite material. This Special Issue of Nanomaterials will attempt to cover the recent advances in carbon nanoparticles for strain and damage sensor applications, including the analysis of electrical conductivity and piezoresistivity of carbon nanoparticles/polymer nanocomposites, the relationship between them, the tunneling effect, sensitivity to different load modes, theoretical and numerical studies, etc.
Keywords: carbon nanoparticles; functional composites; strain sensor; damage detection; structural health monitoring; electrical properties.