Like many other industries, the coatings industry has experienced considerable growth and development over the years. The emergence of new technologies, new processes, new materials and new skills has greatly expanded the application range of various paints and coatings, enabling them to adapt to the rapidly changing needs of consumers.
Graphene is a material that is revolutionizing the way we formulate paints. Since its introduction in 2004, this material has attracted great attention from many professionals, especially those in the field of materials science. Scientists in the paint industry have found ways to use graphene as an additive to enhance the performance of various paint technologies. This material has become especially important in modern high performance and demanding industries where coatings are required to consistently deliver exceptional performance in challenging and aggressive environments.
What is graphene?
Graphene is an allotrope (another physical variant or form) of carbon. It is essentially a single layer of carbon atoms arranged in a hexagonal lattice. Imagine a flat hexagonal network of interconnected carbon atoms (Figure 1). Graphene's two-dimensional single-layer geometry makes it an infinitely large molecule, only one atom thick. Stacked graphene layers held together by weak bonds form the molecular structure of graphite, one of the common allotropes of carbon.
While scientists knew of the existence of this one-atom-thick 2D material, it had never been extracted under laboratory conditions. Then in 2004, two researchers at the University of Manchester, Professor Andre Geim and Professor Kostya Novoselov, developed the technique to successfully isolate individual graphene layers.
Graphene has many remarkable and unconventional properties. Over 200 times stronger than steel, thinner, lighter , and one of the man-made materials that are more thermally and electrically conductive.
How is graphene used in paints?
One of the more effective ways to harness the power of graphene is to use it as an additive (that is, to combine it with other materials) to enhance the performance of existing products; in this case, paints and coatings.
Past paint formulations have traditionally employed inorganic filler materials to modify the properties of polymeric paints. It is well known that popular nanoscale coating additives mainly composed of layered clays, nanotubes, and spherical silica nanoparticles exhibit relatively poor compatibility when mixed with organic polymer resins; thus further modification of the filler's surface is required , to improve the filler/matrix interaction.
The carbon-based composition and enhanced compatibility of graphene make it a viable filler for organic polymers. Therefore, graphene nanosheets, nanoplates, and oxides have been extensively studied as fillers in various types of coating formulations.
One of the main uses of graphene coatings is corrosion protection. Graphene helps prevent corrosion through a defense mechanism called barrier protection. During this physicochemical protection process, the graphene in the coating acts as an impermeable layer that prevents air, moisture and salts (in some environments) from coming into contact with the underlying steel substrate; thereby blocking the electrochemical reactions that initiate corrosion. This type of protection is mainly due to the hydrophobic (hydrophobic) properties of graphene.
Figure 2. Results of ASTM G85 adhesion testing conducted by Applied Graphene Materials, Inc., demonstrating enhanced performance of graphene coatings compared to control samples.
While recent research has mainly focused on the use of graphene and graphene composites as a means of corrosion protection, the scope of research on graphene coatings and their application as additives is very diverse and opens up a wide variety of enhancements and potential applications. possibility.
Research has shown that when combined with compounds that provide galvanic protection, such as zinc-rich primers, the barrier protection provided by graphene complements the sacrificial zinc layer, resulting in extraordinary coating formulations capable of extending the life of substrate products life. Furthermore, while standard anti-corrosion coatings need to be applied in relatively thick layers, graphene can provide adequate barrier protection and can be applied in much smaller thicknesses.
Uses of Graphene Coatings
Graphene's extraordinary strength and negligible weight are ideal for a wide variety of coating formulations in industries where durability, weight and water resistance are of paramount importance. These surfaces may include ship hulls, pressure vessels, pot/pan liners and glass surfaces. Substrates that require reliable protection from aggressive chemicals, fire, moisture, corrosion and UV degradation can also benefit from the properties of graphene coatings. Industries that may be exposed to these types of harsh environments include aerospace, electrical, alternative energy and specialty chemical industries.
Some advantages of using graphene coating formulations include but are not limited to:
a. Excellent substrate adhesion
b. Excellent outer coating properties
c. Reduce maintenance costs
d. Extended maintenance intervals
e. Improve corrosion resistance under corrosive conditions
in conclusion
The advent of graphene coatings and composites has already left its mark on numerous industries with its superior performance over conventional protective coatings and its wide range of application possibilities. While this type of coating is still classified as an emerging technology, its multifunctional properties, including enhanced durability, electrical conductivity, chemical resistance, and corrosion resistance, make graphene a promising technology with market potential. Highly good coating additive.
