EXPERIMENTATION FOR FLEXURAL STRENGTH AND FRACTURE TOUGHNESS ON CARBON AND GLASS FIBER SELF-HEALING COMPOSITES WITH BISPHENOL A DIGLYCIDYL ETHER AND AMINE MICROCAPSULES

Abstract

The present study investigates self-healing ability of carbon/E-glass fibers composites based on microcapsule approach under flexural and fracture loading. The proposed self-healing fiber reinforced composite constitutes epoxy resin (Lapox ARL-136+AH-126), unidirectional carbon, and E-glass fibers with different orientations such as 0°, 45°, and 90°, microcapsules of BADGE (monomer) and amine with AH-319 hardener as curing agent are embedded. The self-healing ability of the developed composites at different healing time (5, 6, and 7 days) and comparison of recovered flexural strength for carbon/E-glass fiber along different orientations are studied. On day 7 the healing efficiencies obtained are 61.89, 61.20, 78.30% and 64.50, 68.55, 82.77% for carbon/E-glass fiber orientation along 0°, 45°, 90° composite, respectively. By knowing the drawbacks of microcapsule-based system and to reduce the healing time, experimentally fracture properties in mode I, II, mixed-mode conditions, and efficiencies based on extrinsic approach are evaluated. Optimum healing efficiencies obtained in mode I for carbon/E-glass fiber orientation along 45° are 103.51 and 84.16%, respectively. Similarly in mode II for carbon fiber along 0° and E-glass fiber along 45°, obtained efficiencies are 130.32 and 84.48%, respectively. And, in mixed mode for carbon fiber along 90° and E-glass fiber along 45° obtained efficiencies are 232.78 and 119.23%, respectively. Optimum fracture toughness of healed is 75% as compared to virgin samples. The results show that the self-healing composites may provide excellent mechanical and fracture properties towards a wide range of structural applications.