Smart Coatings with Carbon Nanoparticles

Abstract

Smart coatings based on polymer matrix doped with carbon nanoparticles, such as carbon nanotubes or graphene, are being widely studied. The addition of carbon nanofillers into organic coatings usually enhances their performance, increasing their barrier properties, corrosion resistance, hardness, and wear strength. Moreover, the developed composites provide a new generation of protective organic coatings, being able to intelligently respond to damage or external stimuli. Carbon nanoparticles induce new functionalities to polymer coatings, most of them related to the higher electrical conductivity of nanocomposite due to the formation of percolation network. These coatings can be used as strain sensors and gauges, based on the variation of their electrical resistance (structural health monitoring, SHM). In addition, they act as self-heaters by the application of electrical voltage associated to resistive heating by Joule effect. This opens new potential applications, particularly deicing and defogging coatings. Superhydrophobic and self-cleaning coatings are inspired from lotus effect, designing micro-and nanoscaled hierarchical surfaces. Coatings with self-healable polymer matrix are able to repair surface damages. Other relevant smart capabilities of these new coatings are flame retardant, lubricating, stimuli-chromism, and antibacterial activity, among others.

Graphene nanoplatelet, multiwall carbon nanotube, and hybrid multiwall carbon nanotube–graphene nanoplatelet epoxy nanocomposites as strain sensing coatings

“…The first result was expected, since it has been reported that MWCNTbased strain sensors have generally limited sensitivity. 13,66,67 Sensitivity is much higher in low density network since fewer parallel conduction pathways contribute to the electrical conductivity. 64 In this work, the MWCNT network at 1% wt loading is quite dense; therefore, the applied strain does not greatly affect the CNT-to-CNT pathways resulting in low sensitivity.…”

Sustainable Coatings on Metallic Alloys as a Nowadays Challenge

“…Smart coatings based on the polymer matrix doped with carbon nanomaterials, such as carbon nanotubes or graphene, enhance their performance, increasing their barrier properties, corrosion resistance, hardness, and wear strength [151][152][153][154][155]. This is a new generation of protective organic coatings, capable to respond intelligently to damage or external stimuli.…”