Zentek Presents Icephobic Coating Tech Update
Zentek Ltd., a Canadian development and commercialization company, has recently provided an update on testing results for its icephobic coating technology.
The carbon-based, nanotechnology-enhanced coating was first announced last year and has shown “excellent” results in previous testing. The company’s latest update includes results from its rain and sand erosion testing, moving the coating one step closer to wind turbine and drone use.
About the Coating
Zentek announced the development of its new carbon-based, nanotechnology-enhanced icephobic coating in November.
Tests for adhesion strength required to dislodge ice from surfaces were conducted with a third-party lab, with the coating reportedly demonstrating an adhesion strength consistently around 20 kilopascals. Zentek reported at the time that the typical ice adhesion strength of a bare aluminum alloy is about 500 kilopascals, while a classified icephobic surface must be less than 100 kilopascals, with the coating having a 96% improvement over aluminum and 80% improvement over the 100 kPa threshold.
“We continue to actively develop new nanotechnology-enabled applications in high-impact areas, which, in this case, has the potential to significantly increase safety for vehicles such as drones, aircraft, ocean vessels, wind turbines and other applications where, in cold weather climates, there is the potential for ice to accrete on surfaces, causing hazardous breakdowns in function,” said Greg Fenton, Zentek CEO, at the time.
“Our mission continues to be to develop innovative nanotechnologies that improve people’s lives – and while our focus is primarily on nanotechnology-enabled healthcare solutions – we are also making breakthroughs that substantially contribute in other industries that may result in vital steps forward to ensure public safety and enhance sustainability.”
At the time, Zentek announced plans to include the coating, which includes graphene, in flight testing under real world ice-forming weather conditions over the winter. In addition, the company also planned to test if the coating was an effective passive method to de-ice drone propellers to fly safely in all-weather operations.
The company had also filed a provisional patent for the technology last August with the United States Patent and Trademark Office and started to explore partnership opportunities.
Earlier this year, in March, Zentek reported the results of testing conducted on its icephobic coating, including real-world testing, drone testing and accelerated age testing.
According to the company’s release, the icephobic coating had “excellent” results in three rounds of testing, including laboratory tests, real-world flights and applications related to drone operations in adverse weather. To test practical application against ice for drone and wind turbine markets, the coating also underwent UV weathering testing.
For the real-world testing, Zentek supplied samples of the coating on test pieces to be attached to research aircraft. These pieces are reportedly undergoing flight trials to target adverse weather environments.
Video footage of the coating performance has shown “positive” results. The coating reportedly demonstrated effective deicing and anti-icing under significant icing conditions.
To test its efficiency with drones, Zentek’s icephobic coating was applied to propellers typically used on drones to test low ice adhesion in applications where external forces can be used to remove ice from a surface.
These coated propellers reportedly demonstrated higher thrust can be maintained compared to noncoated propellers. These results were due to the ability to shed ice that forms on the blades that would otherwise degrade their aerodynamic properties.
Additionally, Zentek believes this demonstrates proof concept that drones can extend their operational temperature range, critical in freezing climates, by using its icephobic coating on propellers.
Finally, to test accelerated aging, the company exposed coated samples to UV weathering for 1,000 hours, approximately two years’ worth of sun damage in typical Canadian weather. After this exposure, the samples were tested in an icing wind tunnel under dynamic conditions.
These samples reportedly demonstrated “significant” retention of their icephobicity. Zentek explains that this suggests good durability under normal environmental conditions as well.
According to the newest update on the technology, Zentek has successfully completed sand erosion testing at the National Research Council in Ottawa, as well as rain erosion testing at the Anti-icing Materials International Laboratory (AMIL).
“These results, when taken with the strong performance under accelerated ageing announced March 14, 2022, demonstrate that the company’s icephobic technology is durable in adverse conditions for both wind turbine and drone industries, where Zentek is currently maintaining its focus,” wrote the company.
The sand erosion testing reportedly demonstrated “medium” to “good” performance at a high speed of 540 kilometers (335.5 miles) per hour.
Additionally, the rain erosion testing demonstrated “good” performance at 160 kmh and 320 kmh. Zentek reports that these speeds are exemplary of which the leading edge of wind turbine blade tips are exposed.
AMIL is also testing the performance of the icephobic coating on a small wind turbine in an indoor controlled environment.
“We are very happy with both the performance and durability test results for our icephobic coating and look forward to continued testing and demonstration of our technology,” said Fenton. “Ice accretion is a significant problem in the drone and wind turbine industries with few robust solutions currently available.
“We believe our patent-pending technology may be a new innovative approach to addressing a significant global need and look forward to continued discussions with drone and wind turbine market participants who see value in potentially more effective icephobic technologies.”
The company reports that it has filed a full patent application with the Patent Cooperation Treaty, the international patent office, on Aug. 2. The patent application, for Nanomaterial-Enhanced Elastomer for Passive Ice Accretion Prevention, will be published about six months from the date of filing.
This marks the beginning of the 12-month national phase for Zentek to apply directly in each country of interest.