Structural micromechanical characterization of the interphase region between two thermoset resins

Janssens de Bisthoven, Yann-Alex [UCL] Coulon, B. [UCL] Voleppe, Quentin [UCL] Sclavons, Michel [UCL] Magnin, Delphine [UCL] Debleser, R. [UCL] Ballout, Wael [UCL] Morelle, Xavier [UCL] Lani, Frédéric [UCL] Bailly, Christian [UCL] Pardoen, Thomas [UCL]

The local interactions at the interface between two thermoset resins are investigated using microscopic, chemical and micromechanical characterization techniques. The novelty of this work lies in the combination of physico-chemical measurement techniques to investigate polymer interfaces. The characterization techniques include scanning electron microscopy, Raman spectroscopy and nano-indentation. The results allow a quantitative analysis of the concentration profile in the interface region. The observation of the interfacial area by Transmission Electron Microscopy also highlights a gradient of morphological structure. This morphological gradient can be correlated to the concentration profile obtained by the other techniques. Based on the analyses, an estimated interphase length of 800 μm is found for the resins studied in this paper. The concentration gradient in resin/prepreg model systems could only be measured by energy dispersive X-ray microscopy. In this case, the length of the interphase was reduced to 500μm.