Next Generation Chrome-Free Flexible Aircraft Primer

ABSTRACT: Coatings on large aircraft undergo significant flexure, creating corrosion sites at seams and fasteners due to the formation of paint bridges on the substrate. Current coatings in use are based on polysulfide chemistry, contain chrome inhibitors, and do not consistently meet flexibility requirements of MIL-PRF-32239A. Luna will develop a next generation chrome-free flexible primer based on a unique hybrid resin chemistry that has been demonstrated via previous Luna efforts to offer epoxy-type rapid reactivity and good adhesion combined with excellent erosion, flexibility, weathering, and chemical resistance typical of polyurethane systems. The primer will be formulated to consistently meet 60% GE reverse impact requirements both pre- and post-Xenon arc testing, and will utilize high performance non-chrome based inhibitors. The final primer will be compatible with existing non-chrome pretreatments and topcoats already on the market to enable a a complete non-chrome aircraft outer mold line. The primer will below-VOC and non-HAPS to ensure compliance with EHS regulations.; BENEFIT: The nonchrome flexible primer will benefit the safety of Air Force and DoD personnel, commercial industry, and the environment.Because of increasingly strict regulations, demand for more environmentally friendly coatings, specifically chrome-free coatings, will continue to grow.The military has taken the lead in demanding complete chrome replacement and greener coating technologies, and the demand for greener coatings is growing in the commercial sector, too.Lunas nonchrome flexible primer is positioned to meet both demands for corrosion control and environmental acceptance.The coating will find use across the Air Force on large airframes such as the KC-46, C-17, C-130, or LRSB where high mechanical flexure has historically resulted in coating system failure. Reductions in corrosion across these structures will result in greater operational readiness and reduced sustainment costs over the platform life.Other commercial applications include numerous DoD aircraft anda wide variety of civilian passenger and transport aircraft.