Fiber Finishes for Improving Galvanic Resistance of Imide-Based Composites

摘要

The objective of this program is the development and demonstration of galvaniccorrosion resistant carbon/BMI composites through the use of reactive finishes to form coatings that isolate the carbon fibers from the BMI matrix. A family of novel reactive coupling agents was formulated into based phenolic finishes for carbon and graphite fibers that will subsequently react with the fiber and matrix resin during processing to form chemical bonds at the interface and in the interphase. In this process, each fiber is coated uniformly with the phenolic finish and bonded to the finish before the BMI prepregging process. The finish serves to isolate the carbon fibers from the BMI matrix and interrupts the galvanic cell. The addition of reactive finishes to fiber surfaces serves the dual purposes of protection of the fiber during handling and alteration of the interphase in the cured composite. The surface protection aspect of finishes will become even more critical as composites technology focuses on the use of 3-D braids and weaves for development of low cost composite processes, such as transfer molding. The reactive finish approach will provide a cost efficient means of improving galvanic corrosion resistance in composites with an BMI formulation.