Alternative Resins for DoD Aircraft
Polyimide Resin-15 (PMR-15) is classified as a polymerized monomeric reactant and is used in the preparation of carbon fiber reinforced composites. It offers greater strength to weight in the extreme range of operating temperatures typically experienced by aircraft engine components. Methylene dianiline (MDA) is a component of PMR-15 that is a known carcinogen and liver toxin. This has generated concern with worker safety and occupational exposure hazards and the Occupational Safety and Health Administration (OSHA) is pursuing new standards and regulations for MDA exposure. Among the international communities, the European Union REACH organization has listed MDA as a substance of very high concern. Although the domestic and international communities are reconsidering MDA regulations, there is currently no legislation in place that addresses the replacement of PMR-15, MDA, or other alternatives.
SERDP has funded several research and development efforts on the topic of MDA alternatives as well as efforts aimed at sustainable PMR-15 alternatives. WP-2442 is a limited scope effort led by Dr. Jason Lincoln at Performance Polymer Solutions, Inc. that aims to develop a patented, low-toxicity polyimide to serve as a PMR-15 alternative. Dr. Teddy Keller ( WP-2440) and a project team at the U.S. Naval Research Laboratory are focusing on developing a new phthalonitrile based resin that will exceed MDA performance standards and serve as a low-cost MDA alternative. At the U.S. Army Research Laboratory, Dr. John La Scala and project team ( WP-2402) are working to identify an MDA replacement from petroleum-derived and renewable/bioderived monomers.