Numerous military aircraft, shipboard surfaces, ground vehicles and related support equipment require durable coating systems to protect the underlying asset against a multitude of stringent environmental conditions. These coatings must provide good chemical and corrosion resistance, excellent adhesion to the substrate and meet many other metrics outlined in MIL-DTL-53039, MIL-DTL-64159 and MIL-PRF85285 Type IV. The majority of approved protective coatings that meet these metrics are polyurethane-based resins that contain hazardous isocyanates. Newer polysiloxane chemistries are free of isocyanates during application and cure, however still utilize isocyanates during their synthesis, leading to an overall detrimental lifecycle impact. A drastic reduction in isocyanates and hazardous air pollutants will lead to significant environmental and occupational safety improvements, as well as reduced coating lifecycle costs and regulatory burden.

The objective of this limited scope project is to develop new polyurethane coatings based on fully non-isocyanate chemistry. This will be accomplished by synthesizing polyurethane (PU) oligomers using non-isocyanate chemistry having reactive functional end groups that can undergo rapid curing under ambient conditions. The PU resin synthetic route will result in high-performance resins that will enable advanced topcoat formulation for military application at ambient temperature and cure. The project team will explore selected isocyanate (NCO)-free PU chemistries and develop baseline topcoat formulations for performance evaluation per MIL-DTL-53039, MIL-DTL-64159 and MIL-PRF-85285, thereby facilitating a possible larger scope follow-on SERDP project focused on coating optimization, scale-up, and transition to Department of Defense (DoD) agencies.

Luna Labs is teamed with Prof. Dean Webster at North Dakota State University to develop new polyurethane coatings based on fully non-isocyanate chemistry. This will be accomplished by synthesizing PU oligomers using non-isocyanate chemistry having reactive functional end groups that can undergo rapid curing under ambient conditions. The PU resin synthesis route will result in high performance resins that will enable advanced topcoat formulation for military application at ambient temperature and cure. This is unique and distinct in that prior non-NCO resins and coating technology either 1) utilize NCO during initial resin synthesis, 2) require ultraviolet curing, or 3) require elevated temperature during the coating application process – a significant logistical burden and increased cost for military systems.

With a successful technology, the return-on-investment for SERDP and the DoD agencies (e.g. Army, Air Force, etc.) in terms of lowered sustainment and environmental costs associated with isocyanate PU coatings will be significant. This is associated with the immense quantity of aircraft, ground vehicles, support structures/equipment, and numerous other critical DoD assets that have traditionally used PU coating systems for environmental protection. Other commercial markets include the energy and infrastructure market, industrial and manufacturing markets, space and hypersonics, commercial aircraft and helicopters, and numerous other opportunities across literally almost every industry. The application market is thus extremely widespread for the technology. Luna will leverage existing internal contacts for collaboration with the U.S. Army, U.S. Air Force, U.S. Navy, aircraft and ship maintenance depots, Prime integrators, and coating manufacturers to facilitate DoD transition.