Advanced battery anode materials and graphene additives provider Talga Resources Ltd commenced a commercial-scale trial of a Talga graphene-enhanced coating applied to a 33,000-ton container ship.

Believed to be the world’s largest single application of graphene, the 700m2 coating of the cargo vessel’s hull is part of the advanced testing of Talga’s functionalized graphene (Talphene) additive as a performance booster for existing commercial marine coatings.

The commercial-scale application follows completion of in-house development and patent-pending technology that successfully translates graphene’s exceptional mechanical properties into paint and coatings. The result is expected to be a range of environmental and economic benefits, which for marine applications such as shipping and offshore infrastructure includes improved corrosion resistance, decreased metallic paint loss into oceanic ecosystems and increased efficiency through lowering dry docking cycles.

The freshly coated ship is now at sea and over the coming 12-18 months, the Talphene-coated area will be evaluated in the harsh real-life conditions of global cargo shipping.

“The maritime coating sector is a very large market and well suited to use of our Talphene graphene additives for improved environmental and economic outcomes," Talga Managing Director Mark Thompson said. "Additionally, by successfully taking this new product from the laboratory to commercial- scale application on a 33,000-ton ship, being tested across global marine environments, we are showcasing our graphene’s real-world potential as a bulk industrial product.”

For maritime applications, Talga’s additive development has included multi-stage testing to optimize graphene loadings (i.e. quantities) and Talga’s patent-pending dispersion technology for epoxy based commercial primer coating systems.

Testing by Talga included industry accepted ASTM prescribed Salt Fog Test (ASTM B117) where steel panels coated with an epoxy primer containing Talphene additive showed improved corrosion protection performance compared to "state of the art" commercial systems currently used worldwide in large volumes.

Further evaluation included mechanical performance tests, carried out to ASTM standard by research organization The Welding Institute, as the coated surfaces of ships and maritime infrastructure are exposed to considerable abrasion and mechanical damage during service.

The results showed a significant improvement in primer performance, including greater adhesion to the substrate (by ~7%), greater interlayer adhesion to the subsequent (antifouling) coating systems (by ~14%) and consistent improvement in abrasion resistance.

These improvements in performance were a notable outcome for this optimized industry, indicating that graphene’s exceptional mechanical properties translated into the coating system and warranted commercial-scale trials.

Based on the successful lab results, plans were drawn up for a major commercial-scale application and sea trial. A 2-part epoxy-based commercial coating system was purchased (AkzoNobel Intershield 300) and mixed with the Talphene additive before dispatch to the ship management company for application during vessel dry-docking (carried out every ~5 years for ships this size).

The test areas along the ship’s starboard side, both below the waterline and above in contact wear sites, were blast cleaned to remove prior paint systems before the Talphene-enhanced primer coating was applied (next to a test reference coating without Talphene) in two coats, using manual spray systems.

A major challenge of the product development was to translate the positive lab-scale tests into practical, large-volume use by on-site commercial applicators. The successful application of the Talphene-enhanced coating without any adverse effect in terms of stability in resin, application, curing and surface features is a highly positive step forward in the commercialization process.

The test areas have been over-coated with the standard topcoats used on the rest of the vessel and marked to ensure identification during service. Periodic inspections will be carried out over the next 12-18 months to determine real-world performance.