HYBRID-PARTICULATE COMPOSITES BASED ON AN EPOXY MATRIX, A REACTIVE RUBBER, AND GLASS-BEADS - MORPHOLOGY, VISCOELASTIC, AND MECHANICAL-PROPERTIES

The deformation and fracture behaviors of hybrid-particulate epoxy com posites have been examined. These materials were based on a DGEBA/DDA matrix with various volume fractions of glass beads and different rubb er contents. Young's modulus, yield stress, dynamic mechanical spectra , and fracture energy have been determined at room temperature. The Ke rner model fits well the Young's modulus for the hybrid complexes with various glass bead contents. The analysis of the relaxation peak reco rded from viscoelastic measurements allow us to discuss the influence of the introduction of the glass beads on the mobility of macromolecul ar chains and the characteristics of the rubber-separated phase. The f racture energy displays a strong improvement and a synergism effect du e to the presence of both kinds of particules. The toughening mechanis ms were discussed. (C) 1993 John Wiley & Sons, Inc.