Biodegradation of Polymeric Coatings and Composites
Final rept. 1 Mar 95-28 Feb 98
DAYTON UNIV OH RESEARCH INST
Pagination or Media Count:
Air Force structures are susceptible to corrosion under normal service conditions. Many of these metallic and polymeric structures can be protected against corrosion by organic coatings. However, routine maintenance, special mission requirements, and the ever-increasing life-cycle requirements of these aircraft structures necessitate periodic stripping of these coatings. The application, stripping, and disposal of these coatings cause a substantial environmental pollution problem for the Air Force. Current metal primers utilized by the U.S. Air Force contain chromates to inhibit corrosion of the underlying metal. These chromates are both highly toxic and carcinogenic and pose a severe health risk to personnel involved in their application, stripping, and disposal. The health risks are of particular concern during the stripping and disposal processes prior to refinishing the metal surfaces. Environmentally-friendly nonchromate replacement primers have historically performed poorly with respect to corrosion inhibition. Microorganisms have been shown to both initiate and accelerate corrosion in many environments. The aim of this study was to investigate the interaction of chromates with microorganisms in an environment not traditionally associated with biologically-enhanced corrosion and to determine it the corrosion inhibiting action of the chromate pigment might be due, in part, to its action as a biocide. The results of this investigation provide some guidance in the search for environmentally-benign chromate replacements.
- Properties of Metals and Alloys
- Environmental Health and Safety