Selfhealing composites

Abstract

Polymer composites used in structural applications are subjected to dynamic loads that can generate fatigue-induced microcracks. As these microcracks grow and merge, they lead to material failure, thereby reducing the service life of the component. To address this challenge, a promising strategy involves the development of smart self-healing polymers that, similar to biological systems, respond to damage by activating self-repair mechanisms, effectively enhancing the durability and lifespan of the material. This study investigates the interlaminar shear behavior of 5HS carbon fiber/epoxy composites containing varying amounts of the self-healing agent EMAA, processed via RTM. It examines the influence of agent content on mechanical performance and confirms, through thermal analysis, the feasibility of laminate fabrication, though particle dispersion may limit agent volume. ANOVA results show that EMAA content has a higher effect on mechanical response than internal dispersion. Weibull analysis indicates a linear decrease in shear strength with increased EMAA due to reduced stiffness from its ductile nature. Healing was most effective in interlaminar regions, achieving up to 62% recovery in shear strength, 106% in toughness, and 57% crack area reduction. Predictive modeling supports optimizing healing agent levels to meet design needs while reducing experimental effort and cost.