Advanced Corrosion Resistant Coating Systems for Preservation of Aerospace and Infrastructure Systems Used in Military and Commercial Applications

ABSTRACT: A new knowledge-based approach is proposed to mitigate the corrosion of metallic surfaces. The approach is based on the rational design of molecular coating materials based on a new class of phthalocyanines. While these materials resemble fluorinated polymers in their capacity to prevent the intrusion of moisture associated waterborne ions and the diffusion of oxygen to the metallic surface, they also exhibit additional beneficial properties unavailable to fluorinated polymers. Characteristically, all residual C-H bonds of classical phthalocyanines are replaced by C-F bonds via the inclusion of perfluoroalkyl groups insuring a high thermal and chemical stability of the materials. The molecules are designed to bind metal ions. The combination of metal ions and the extremely electron withdrawing perfluoroalkyl groups results in the suppression of oxidation (electron loss) and adhesion to metal surfaces via the formation of bonds between the metal center of the proposed molecules and the oxo groups (precursors to rust) present on metal surface exposed to the environment. Taken together the above features insure water repelling (high hydrophobicity) as well as electrochemical suppression of the deleterious effects of oxygen. In addition the coatings resist acids (acid rain) and other harsh chemicals due to the exclusive presence of C-F bonds. BENEFIT: An added feature is the facile manipulation of molecular structures aimed at introducing intermolecular interactions via stacking that will enhance the cohesion of films and possibly their adhesion to metallic surfaces. A wide battery of solutions and solid-state experimental techniques will provide insights at both molecular and solid state (film) level, while additional tests to be performed in collaboration with the corrosion group at the US Army Research Development and Engineering Center (ARDEC), Picatinny Arsenal, NJ will reveal corrosion important prop-erties such as surface energy (hydrophobicity). The experimental effort will be supported by a detailed computational analysis. The target molecules will be investigated using computational chemistry methods designed to complement the experimental results and to predict properties that will enhance the corrosion resistance of these materials. At a molecular level, several properties have been recognized in the corrosion literature as contributing to overall stability of molecules: 1) electron density distribution and atomic charge; 2) energy of the highest occupied and lowest unoccupied molecular orbitals; 3) per-manent dipole moment and polarizability; and 4) total (internal, potential and kinetic) energy. Inasmuch as the target materials represent a new class of corrosion inhibitors, computational methods will be used to probe specific properties of the fluorinated phthalocyanines. As these phthalocyanine materials will be applied as surface coatings on solid materials, their bulk and thin film properties will be examined by classical molecular dynamics. The synergistic interactions between theory and experiment will insure a solid scientific base for the proposed explorato-ry development of a new type of corrosion resistant coating, as well as for future optimization and development efforts. Porter Scientific Incorporated (PSI) is a North Carolina based American Indian woman owned 8(a) HUBZone small business with a distinguished award winning track record of providing environmental consulting services, and of supporting research and development. PSI also provides information technology and facility support services to a variety of clients including the United States Departments of Defense and Transportation, the Environmental Protec-tion Agency (EPA), national commercial entities and local governments and municipalities. Anticipated Benefits: Protection of metallic surfaces is an ongoing economic burden and impairs service delivery in military and commercial environments. For aerospace and infrastructure applications, this project engages exploratory devel-opment of a corrosion resistant coating that will substantially reduce the military systems annual direct cost of cor-rosion which is presently estimated at $20 billion. The corrosion resistant coating will have substantial national de-fense relevance in reducing equipment downtime (during corrosion repair); increasing military readiness; improving equipment and systems integrity while potentially saving lives. The feasibility and potential impact of the proposed coatings are substantial. Potential Commercial Applications: A corrosion resistant coating represents incredible opportunities to expand product life and reduce industry cost in maintenance, repair and replacement. Applications include the homes we live in, the offices we work in, the transportation we utilize, the recreation activities we engage in, and the utensils we use while dining. The commer-cialization of a polymer that extends the half-life of mineral based devices maximizes limited resources of our planet. Product manufacturers improve service delivery by providing consumers with goods that require less direct and indi-rect cost of implementation. The global economy benefits when resources currently used for product sustainability can be directed to other solutions, innovations or efforts. The corrosion resistant coating will spawn opportunities throughout all forces in the Department of Defense. Additionally, the insoluble polymer has the potential for cookware, gaskets, bearings, electrical insulators, recreational and commercial nautical and air transport systems. From cruise ships to lawn chairs to buffet serving utensils - any dimension of user life that includes corrosion of surfaces may be dramatically impacted by expanding life of actual utilities while reducing industry cost in maintenance, repair and product replacement. Key Personnel: Dr. Freda Porter, PSI CEO and President, holds a Ph.D. from Duke University in Applied Mathematics special-izing in Numerical Modeling. Dr. Porter has been involved in Groundwater Contamination research with EPA and Noise Modeling and Simulation research with NASA Langley Research Center. Current initiatives of the corporation include environmental sustainability and green energy topics but focus on military and commercial applications that improve quality of life worldwide. Operating since 1997, PSI has employed skilled personnel working within and establishing innovations to industry standards in Environmental Consulting, Environmental Investigations, Assessments, Remediation and Cleanup, Pollution Prevention, Regulatory Compliance, Water, Sewer and Solid Waste Project Management, Database Management, Information Technology, Education and Outreach, and capitalization of projects. The corporation has been successfully engaged in projects improving manufacturing processes, equipment and systems at the environ-mental level. While primary operations exist in North Carolina, PSI has provided government contracting to numerous clients in AR, AZ, CA, FL, GA, MS, NJ, PA, SC, SD, TN, TX and VA, serving more than 20% of the United States. Twenty two employees of PSI have corporate headquarters in Pembroke, North Carolina in a 21,000 square foot facility ad-jacent to The University of North Carolina at Pembroke. PSI has a bonding aggregate of $8 million, a line of credit of $1 million, and a Secret Level Facility Security Clearance. Professor Sergiu M. Gorun will serve as Principal Investigator. Dr. Gorun holds a Ph. D. from MIT and is ac-tively engaged in research areas that include novel materials aimed at constructing catalytic artificial enzymes and the design of solid-state structures using molecules lacking C-H bonds, robust metal-organic materials for chemically and biologically active low-energy surfaces. He is currently a part-time Research Professor in the Department of Chemistry and Biochemistry at Seton Hall University, NJ. Professor Stephen P. Kelty is a distinguished collaborator on this research. Dr. Kelty is currently the Chair of the Department of Chemistry and Biochemistry at Seton Hall University and the Director of the University Center for Computational Research. His current interests focus on Theoretical Chemistry. Significant support for the project will be provided by the US Army. ARDEC scientists have been engaged in research with Professor Gorun since 2005 and have committed to insure surface science and related corrosion test-ing of the new coatings. A letter of support from the US Army appears in Section 5.