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Low ice adhesion strength coatings are only useful insofar as they remain on the surface of interest, and aircraft leading edges experience extreme environmental conditions during flight. Ensuring durability while maintaining performance – in this case, reduction of impact (i.e., accreted in-flight) ice adhesion strength – is critical to meeting the needs of the aviation industry and other commercial applications. To that end, NASA engineers investigated coating compositions comprised of epoxy resins, including aromatic and aliphatic resins, and aromatic diamine hardeners. Several nonreactive additives were incorporated and tested. The first was holey graphene, a unique nanomaterial made by partly oxidizing areas of graphene that already have defects. This creates high energy functionalities that result in good dispersion throughout the matrix, enabling the mechanical properties of graphene to be imparted throughout the coating. Secondly, micrometer-sized core-shell rubber particles were dispersed throughout the epoxy resin to increase toughness. Finally, a series of polyhedral oligomeric silsequixones (POSS) were used for mechanical reinforcement. Several different coating formulations were development and tested, each incorporating different relative amounts of additives, with good results. Thus, the coatings can be tailored to meet different application-specific requirements. NASA's coating formulations, with further development, may be suitable for in-flight (i.e., impact) ice adhesion reduction on aircraft leading edges and other platforms exposed to harsh environments.