What is a coating?
A coating is a covering that is applied to the surface of an object. The purpose of applying the coating may be decorative, functional, or both. Coatings are ubiquitous and can be found on walls, furniture, on all sorts of wires and printed circuits, the outside of houses and cars, and much more. In addition, the decorative duties of coatings span quite a broad spectrum.
Decorative coatings are mainly used for their color, texture or other visual property. Functional coatings are applied to change the surface properties of the substrate, such as adhesion, wettability, corrosion resistance, wear resistance and more. In some cases, the coating adds an entirely new property such as a magnetic response or electrical conductivity and forms an essential part of the finished product.
Coatings may be used in various processes, that are roughly divided into: vapor deposition, spraying, chemical and electrochemical techniques, roll-to-roll coating processes and other, less prominent techniques.
What is graphene?
Graphene is a two dimensional layer of carbon atoms, arranged in the form of a honeycomb lattice. It is touted as a “miracle material” because it is endowed with an abundance of astonishing traits - this thin, one atom thick substance is the lightest, strongest, thinnest material known to man, as well as the best heat and electricity conductor ever discovered - and the list does not end there. Graphene is the subject of relentless research and is thought to be able to revolutionize whole industries, as researchers work on many different kinds of graphene-based materials - each one with unique qualities and purpose.
Graphene for coatings
The vast selection of extraordinary properties that graphene possesses can open the door to many interesting types of coatings, paints, inks and more. Graphene's high resistivity can make for durable coatings that do not crack and are resistant to water and oil; its excellent electrical and thermal conductivity can be used to make various conductive paints, and a strong barrier effect can contribute to extraordinary anti-oxidant, scratch-resistant and anti-UVA coatings.
Graphene enables a wide array of functional coatings and paints, for many possible applications. Among these can be high performance adhesives enabled by graphene's high adhesion property, anti-bacterial coatings, solar paints (capable of absorbing solar energy and transmitting it), paints that provide isolation for houses, anti-rust coatings, anti-fog paints and UV ray blockers, non-stick coatings for various domestic applications (like frying pans and countertops) and even a much-hyped possibility (currently under scientific examination) of a coating that turns a regular wall into a screen.
Commercial activity
Graphene-enhanced products are yet to reach widespread commercialization. Nonetheless, given graphene’s impressive array of properties and the vigorous R&D that is taking place, graphene-enhanced coatings should not be too far away.
The Sixth Element Materials, a Chinese company that focuses on R&D, mass production and sales of graphene and related materials, showcased its graphene-zinc anti-corrosion primer used for offshore wind power tower, that can come at a competitive price compared with zinc rich epoxy primer.
Garmor, the University of Central Florida spin-off formed to develop a new graphene oxide flakes production process, has developed graphene oxide-based coatings useful for limiting UV radiation damage to sensors and polymers. Garmor's transparent GO-films are reportedly derived from a commercially-viable and scalable process that can be readily implemented with minimal constraints.
Four layers of GO coating on polycarbonate
The Spain-based Graphenano announced the launch of a graphene-based series of paints and coatings called Graphenstone in 2014. These are said to be very strong and also acts as a protective layer against environmental damage. Graphenstone is made from a graphene powder and limestone powder.
The British Electro Conductive Products released a sprayable transparent conductive coating based on a CNT and graphene platelets (GNP) hybrid material. TBA are targeting the food, electronics, pharmaceuticals and petrochemicals markets.The new ATEX-compliant product is available as a clear, anti-static aerosol, and it should also be available as bulk paint. Its application will safeguard electronic equipment used in explosive environments and bring it up to European standards.
Further reading
The latest graphene coating news:
On SP Nano’s cutting-edge graphene and CNT dispersion technology
This is a sponsored post by SP Nano
Israel-based SP Nano developed a unique dispersion technology based on a genetically engineered exceptionally stable protein that is highly suitable for carbon nanoparticles (CNPs) dispersion, including graphene, CNTs and carbon black.
Following years of intensive R&D, SP Nano is now offering its dispersions to application developers. This is the first time that carbon nanomaterials can “truly” be dispersed and achieve cutting-edge performance across a wide range of applications.
SP Nano’s dispersions are now being applied to a wide range of applications, such as
- Coatings (textiles, surfaces, powders, etc.)
- Dispersions in matrices (resins, polymers, etc.)
- Liquid formulations (coolants, inks, slurries, etc.)
Gerdau Graphene unveils anti-abrasive graphene-enhanced architectural paint
Gerdau Graphene has announced that it has created a new water-based graphene-enhanced architectural paint that is significantly more durable and resistant to abrasion than traditional paints. The new paint could be used on concrete, cement, metal, and asphalt, such as on sidewalks, bicycle lanes, garages, staircases, sports courts, and a wide array of commercial and industrial areas.
Its parent company, Gerdau, reportedly began applying the new paint to its factory floors in March, making it the world’s first large-scale use of a water-based graphene-enhanced architectural paint. The company is already selling its proprietary graphene additives as development prototypes to major paint producers in the Americas.
Sparc Technologies announces progress in commercialization of graphene coatings
Sparc Technologies has reported that significant progress is being made on the way to a successful commercialization of its graphene additive coating products.
Sparc has addressed the issue of graphene's tendency of re-agglomeration, that makes achieving homogeneous dispersions more challenging. Sparc's developments could benefit not only coatings companies, but also companies involved in composite materials.
Zentek announces opening of its industrial scale ZenGUARD production facility
Zentek has announced that it will be opening its industrial scale ZenGUARD™ antimicrobial production facility in Guelph, Ontario on June 17th, 2022. This facility is claimed by Zentek to be one of the largest nanomaterials-based manufacturing facilities in the world.
“The opening of this facility is an important milestone for our company as it represents our successful journey from the lab, through regulatory and now to industrial commercialization. I would like to personally thank all our employees and vendor partners who put in considerable time and effort to make this happen,” said Greg Fenton, CEO of Zentek. “We’re now ready to begin meeting the growing interest and demand for our ZenGUARD™ coating.”
Researchers discover unique water-repellent graphene
Researchers at the Harvey Mudd College in the U.S have made an unexpected discovery that holds exciting potential for creating robust water-repellent coatings using gas-phase-synthesized graphene (GSG) and other nanomaterials.
Last summer, the researchers were working on two projects: A National Science Foundation-funded project characterizing nanocomposites and a project supported by the College’s Rasmussen Summer Research fund that involved using graphene to separate oil from water. “While working on these projects, the students discovered that water droplets falling on our graphene powder were easily sliding off and bouncing from it,” says Albert Dato, author of the paper. “This was a completely unexpected result since we weren’t even looking into this phenomenon called superhydrophobicity.”