POTENTIAL AMINOQUINONE INHIBITORS OF CE AND BMI/CARBON FIBER/ALUMINUM COMPOSITE GALVANIC DEGRADATION

摘要

Bismaleimide (BMI) and cyanate ester (CE) resins are susceptible to degradation by hydrolysis. The chemical conditions necessary to effect resin hydrolysis can be generated by galvanic activity induced in resin/carbon fiber/metal composite structures by salt water/air environments. The objective of this study was to identify resin additives that mitigate resin hydrolysis by mediating the production of chemically basic galvanic corrosion byproducts. A number of aminoquinone compounds were both synthesized and procured for testing as potential inhibitors of the galvanic degradation observed in CE and BMI resin/carbon fiber/aluminum composite structures. It was found that compounds that indicated redox activity in non-aqueous cyclic voltammetry testing, and were soluble in the resin matrix, provided levels of resin hydrolysis protection. This was shown in model CE composites with carbon fiber (70 percent by weight) under accelerated exposure conditions. The use of these inhibitors in certain aircraft composite structures could either alleviate the requirements for extensive structures overdesign or provide additional degradation protection.