Today’s coatings used on military aircraft, tanks and transport vehicles meet all the services’ requirements of durability, stealth and performance. However, when it comes to chemical and biological threats, they sometimes soak up these agents like a sponge, potentially exposing military personnel to deadly hazards.
That’s why the scientists at the Defense Threat Reduction Agency’s Chemical and Biological Technologies Department (DTRA CB) are looking at establishing new standards to meet both emerging and established threats.
“Although our current crops of coating materials meet the current criteria, we feel that a new standard needs to be established,” explained Dr. Revell Phillips, manager, DTRA CB’s Coatings Program at Ft. Belvoir, Va. Phillips recently gathered approximately 40 to 50 government, academic and industry representatives from various backgrounds and disciplines in a coatings colloquium to talk about what the new standards should be. “This gave us a great opportunity to brainstorm and collaborate to come up with real-world solutions,” he said.
CARC – Chemical Agent Resistant Coatings
The chemical resistance standards for the Department of Defense’s Chemical Agent Resistant Coatings, or CARC, for tactical vehicles have been developed and used for the past 40 years. While the standards for many of CARCs characteristics have evolved over the years, those for decontamination and resistance have remain unchanged. Phillips hopes his research will deliver the required results to start implementing incremental changes to the standard within the next year. He points out that raising the bar incrementally for manufacturers makes the transition to a new crop of protective coatings more feasible and likely to succeed.
A similar approach was used to great success in reducing the amount of volatile organic compounds the coatings release while curing. He also pointed out that determining the correct tests to use is critical to getting the best results. Gathering the scientists together, as they did in the recent coatings colloquium, helped guarantee success. Incremental implementation will leverage the expertise of the coating industry by encouraging the individual coating manufacturers to use technology advances and internal research and expertise to improve the chemical agent resistance and the ability of chemical agents to be removed from military coatings. DTRA CB wants to protect the warfighter and stay ahead of emerging threats that the current standard of CARC typically absorbs.
HaMMER and Nanocomposite Coatings
To protect the warfighter, in addition to evolving the agent resistance standards for coatings, scientists working for DTRA CB are also conducting several programs, such as the Hazard Mitigation, Material, and Equipment Restoration (HaMMER) Advanced Technology Demonstration (ATD), omniphobic fluid repellent coatings, and nanocomposite coatings to protect warfighters from chemical and biological threats from certain agents.
HaMMER, a DTRA CB-funded program that has been demonstrated by soldiers on actual vehicles in field conditions, takes a tailored, all-hazards approach to mitigate current and emerging chemical and biological threats. Using a family-of-systems approach, HaMMER demonstrated the synergistic effects of a three-phased system utilizing strippable coatings, agent disclosure products and new decontaminants. HaMMER operational demonstrations began with applying an Akzo Nobel strippable coating to vehicles prior to entering the battlefield. During decontamination operations, a newly developed agent disclosure spray, that readily changes colors in the presence of agent, was applied to the coating to quickly locate areas of contamination. Crew members were then able to rapidly peel off the coating and/or apply decontaminants only to the contaminated areas without having to scrub the entire vehicle, significantly reducing labor, time and resources. The results were some of the lowest post-decontamination levels seen to date.
For omniphobic fluid repellent coatings, researchers are looking at a number of options from hardening the coatings with improved crosslinking, a process to build up a three-dimensional network at a molecular level to give the coating better structure, to using resistant additives much like a beefed up version of “scotch-guarding” a material. Working at the nanoparticle level, DTRA CB-funded research is now looking coating additives that would sequester and deactivate harmful agents.
“We believe that through these research efforts and the evolution of the agent resistance standard in collaboration with industry will help us get to coatings that are more easily and completely decontaminated, protecting warfighters faster, better and sooner,” said Phillips.
Source: DTRA press release, adapted.