Title High-Temperature Finishes/Sizings for Polyimide Matrix Composites
Source Proc. 51st Intl. SAMPE Symp. and Exhib
Year 2006
Author(s) Allred, R. E.; Hoyt Haight, A. E.; Wesson, S. P.
Abstract This study was undertaken to determine the feasibility of developing new high temperature sizings and finishes for bonding carbon fibers to an AFR-PE-4 polyimide matrix. Grafil 34-700 carbon fiber was selected for use in the study. Unsized fibers and those using either a solvent applied polyetherimide sizing or a reactive finish containing a polymer similar to AFR-PE-4 were processed into unidirectional AFR-PE-4 matrix composites and characterized and tested. Difficulties were encountered in processing the laminates to a uniform quality using compression molding. Volatiles were trapped in the center of all the laminates produced; however, well consolidated material away from the center was used for mechanical testing. Interface sensitive mechanical test results and failure surface analyses show that the laminates with all three types of fibers were well bonded at the interface with the laminate containing fibers with reactive finish being slightly better under room temperature, dry conditions. It is expected that moisture and thermal aging will further separate the interface effects with the reactive finish being superior because it forms chemical bonds at the interface between the carbon fibers and polyimide matrix.
Keywords interface, surface analysis, phenylethynyl imide, sizing, coupling agents, carbon fiber, high-temperature, composites, polyimide, AFR-PE-4, interface, reactive, thermal aging