Analysis of polymeric composite interphase regions with thermal atomic force microscopy

Previous work on the characterization of interphase regions in thermosettin g composite systems has focused on the inference of an interphase layer fro m effects noticed through macroscale mechanical and thermal testing. With t he development of atomic force microscopy and active thermal probes for thi s technique, it is now possible to examine material thermal properties on a much smaller scale. Variations in microscale thermal properties of an aero space-grade thermosetting resin system were evaluated for car;bon and glass fiber reinforcement, using the modulated local thermal analysis mode of a TA Instruments 2990 mu TA. The variations observed clearly demonstrate the presence of a soft interphase layer in the glass material and underline the importance of fiber-matrix interactions during the formation of the interp hase. (C) 2001 John Wiley & Sons, Inc. J Appl Polym Sci 80: 1643-1649, 2001 .