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.
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.
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.
The latest graphene coating news:
James Briggs set to launch graphene-enhanced paint primer following collaboration with Applied Graphene Materials
Applied Graphene Materials has a longstanding collaboration with James Briggs, one of Europe’s largest consumer chemicals companies, to develop graphene-based anti-corrosive coatings. Now, an announcement has come out regarding the fruit of this collaboration - a range of graphene-enhanced anti-corrosive vehicle paint primer is set to launch in the next few months.
James Briggs (JBL) has reportedly prepared its first commercial batch in preparation for full product launch. "JBL has successfully completed its first production batch which is a significant milestone for commercial realization".
Versarien has announced that it has signed a Memorandum of Understanding ("MOU") with China Tiesiju Civil Engineering Group Co Ltd. ("CTCE"), a subsidiary of China Railway Group Limited ("CRG").
CRG is one of the world's largest construction and engineering contractors and is listed on the Shanghai and Hong Kong Stock Exchanges. CTCE is specifically focused on railway, bridge, tunnel and highway infrastructure engineering. It is active in China and overseas, including in Asia, Africa, Latin America and the Middle East.
water technology company G2O recently announced a £1.035 million investment in a round led by private equity firm Maven Capital Partners, and plans to sign collaborative partnerships with suppliers and enter global markets to expand customer reach.
Maven Capital Partners, one of the UK’s most active private equity firms, has led a £1.035 million investment in Manchester-headquartered water treatment technology business. A total of £600,000 has been provided by Maven funds, which includes a £400,000 investment from NPIF – Maven Equity Finance, which is part of the Northern Powerhouse Investment Fund and a £200,000 investment from the Finance Durham Fund, both managed by Maven. The additional £435,000 is from a number of private individual investors.
Scientists from The University of Manchester have combined graphene with the natural fiber jute, to create graphene-strengthened natural jute fiber composites. The team explains that this could lead to the manufacturing of high-performance and environmentally friendly natural fiber composites that could replace their synthetic counterparts in major manufacturing areas, like the automotive industry, ship building, durable wind turbine blades and more.
It could also boost the farming economies of countries such as Bangladesh, India, and China – where the jute material is mainly produced – the researchers from The University of Manchester claim. Jute is extracted from the bark of the white jute plant (Corchorus capsularis) and is a 100% bio-degradable, recyclable and environmentally friendly natural fiber. It is also the second most produced natural fiber in the world – after cotton – and is at least 50% cheaper than flax and other similar natural fibers.
Graphene oxide and alginate combine to create new ‘smart’ material with potential biomedical, environmental uses
Researchers at Brown University, the University of Wisconsin and the National University of Singapore have developed a way of reinforcing hydrogel materials made from alginate, a natural material derived from seaweeds that’s currently used in a variety of biomedical applications, by incorporating graphene oxide into its structure.
This produces a material that can be 3D printed into structures that are stiffer and more fracture resistant than alginate alone - an important achievement as alginate tends to be fragile and thus hard to work with. Furthermore, the material is also capable of becoming stiffer or softer in response to different chemical treatments, meaning it could be used to make “smart” materials that are able to react to their surroundings in real time. In addition, alginate-GO retains alginate’s ability to repel oils, giving the new material potential as an anti-fouling coating.