AMC Develops Greener Smoother Coating for Ships and is Rigorously Testing in Europe and Asia
Advanced Marine Coatings has developed a marine coating that enables vessels to slice through oceans more speedily. AMC, which specialises in nano modified coating systems, has harnessed breakthrough nano-science and a patented dispersion technology to make a type of paint with exceptional abrasion resistance and smoothness. These products, trade-named Green Ocean Coatings, are being rigorously tested in Europe and Asia, and could make a significant difference to ships’ speed and fuel consumption. This innovation will bring cost savings for ship owners and positive effects for the environment.
In mid-2009, AMC subjected Green Ocean Coatings to the ultimate trial – applying it to large areas of the subsea and top side of an LNG (liquefied natural gas) tanker. The ship, Berge Arzew, operated by leading gas marine transportation provider BW Gas, is the first vessel to test the anti-fouling version of Green Ocean Coatings. Initial monitoring has been positive, and helpful in further development of the new technology.
AMC has recently launched Green Ocean Coatings and has been applying its nano strengthened coatings on several more vessels in cooperation with BW. It has also recently started on a coating that targets seismic vessels and their streamers.
“We are experiencing keen interest for our line of marine coatings due to the promising test results and our ability to deliver a solution that meets our customers’ requirements,” says Erik Staubo, Managing Director, AMC.
How it started
In 2006, the company experimented with a nano-modified epoxy coating formulation applied on a speed boat. Preliminary tests showed that the coating made a difference of several knots in terms of the speed, compared to traditional anti-fouling paints. Over the next three years, AMC continued to improve the formula. Subsequent tests on different types of boats with depths of up to 40 meters demonstrated an increase in speed of 6 to 10%, or a corresponding reduction in fuel consumption.
The small but formidable development team of five, who together have chalked up 120 years of experience in polymers, were determined to refine the entire coating process.
After trying several application methods such as brush, roller and component spray, the team concluded that the traditional 1-component spray method works very well and the modern 2-component spray method gives even better results.
Paal Skybak, R&D Director, AMC, says: “We want to deliver the greatest value to users, not only by developing an economical and ecologically friendly coating, but also by advising on the best way to apply it.”
How it works
The secret to the coating lies in the carbon nano tubes (CNT) which are evenly distributed in a liquid resin. The tubes reduce viscosity and work as a tough reinforcement to the coating. German company Bayer MaterialScience, one of the world’s largest polymer companies, supplied the tubes under the trade name Baytubes.
"This is the first application of Baytubes in marine coatings to our knowledge ", says Dr. Raul Pires, head of Global Activities for Nanotubes and Nanotechnology Products at Bayer MaterialScience. The coatings are suitable for new vessels and for subsequent repair and maintenance coatings.
Bayer’s CNT are delivered in the form of lumps or agglomerates, which are normally difficult to disperse in liquids. With a patented Finnish technology, these lumps can be dissolved into separate tubes spread evenly throughout the epoxy system.
AMC went on to partner with the Finnish firm Amroy Oy and has obtained worldwide exclusivity to use this technology in marine coating systems.
Skybak adds: “This is an ideal partnership. It has formed the foundation for developing several subsea and topside marine protective coatings with properties superior to those of traditionally reinforced epoxy coating systems.”
Why it is better
The nano tubes are approximately 20 nanometres in diameter and several hundred nanometres long. Spreading out 20 grams of CNT will yield an area as large as the surface of a soccer stadium. Therefore a small addition of these super strong, tiny carbon tubes will improve the abrasion resistance by at least 100% compared to traditional, solvent borne epoxy systems.
Carbon tube reinforcement is also beneficial for fatigue and dynamic mechanical properties. Most surfaces on a ship are exposed to vibrations and continuous movements. In ballast tanks, moving steel surfaces, combined with rapid temperature changes and salt water, challenges the adhesion properties and wear resistance of the protective coating. The tubes provide a stable, flexible coating surface without having to compromise on other mechanical properties including wear resistance and adhesion to a steel surface.
The familiar UV-stabilizing effect usually associated with carbon black has also been achieved by modifying epoxy with nano carbon tubes. AMC’s Green Ocean Coatings can withstand long term exposure to the African sun with less yellowing, compared to traditional epoxy coatings. This has been confirmed in weathering tests on location and in labs.
Green Ocean Coatings do not contain any thinner. The solvent-free products result in pore-free and sleek surfaces after curing. In addition to its good adhesion properties and pore-free nature, the barrier properties of the nano reinforced coatings are superior. Therefore both deck and hull coatings based on AMC’s research have shown convincing results.
By modifying the binder systems with other polymers and nano particles, the friction and hydrophobic properties have been optimized in applications where the coatings are exposed to extreme wear and abrasion as well as dirt- and chemical attacks. Hydrophobic modified surfaces are very dirt repellent and development work to obtain a so-called “Lotus Effect” is promising. The Lotus Effect refers to the very high water repellency and self-cleaning property exhibited by the leaves of the lotus flower in nature.
High quality anti-foul coatings are in high demand. After the removal of tin-based anti-foul biocides in international shipping in 2003, new systems have proven to be less effective in many waters. Therefore, anti-foul coatings with superior wear resistance, which can be scrubbed, have grown in popularity during the last years. Here the AMC subsea programme shows superior properties to traditional 2-component systems. By combining new biocide technology and existing nano technology, AMC expects to obtain superior performance in this niche field.
Since 2006, a station to test new anti-fouling systems for the Green Ocean Coatings has been in operation in the Oslo fjord area. New test stations have been set up both in Europe and in Asia, where cooperation with the National University of Singapore is boosting AMC’s research efforts.
The long Norwegian winters make the water too cold for testing of new coating formulations. This has meant that in the past AMC's tests can be carried out only for 3 to 4 months of the year in the Oslo fjord area. In search of a warmer, tropical test bed, AMC sought assistance from the National University of Singapore. Testing in Singaporean waters allows AMC to accelerate its innovation process for new anti-fouling technology.
How it is evolving
To accelerate this development, AMC and its partners are cooperating with notable Norwegian research institute SINTEF to participate jointly in an EU 7 research programme under the name MUST (http://sintef.org/Projectweb/MUST), where an extensive network has been established. MUST involves participation from several other large European institutes and reputable industry leaders like Daimler, Fiat, EADS, Chemetal, and SIKA. MUST aims to develop new nano container technology for inhibition of corrosion and for anti-fouling prevention.
Green Ocean Coatings is widely regarded to have vast potential and AMC receives sponsorship for it through a development programme funded by Innovation Norway and the Norwegian Research Council. In cooperation with the Norwegian coastal passenger ferry company, Torghatten Nord AS, several types of Green Ocean Coatings have been applied by Norwegian ship yards on ferries and tested since 2007 with promising results.
The hard coats modified with biocides or foul release systems have resulted in superior friction properties in water with reduced drag and fuel consumption. Green Ocean Coatings also reduces the emissions of CO2, NOX and other gaseous pollutants. With its myriad of advantages, the development of Green Ocean Coatings has become the highest priority for AMC.
For further information, please log on to www.amcoat.no