The self‐healing material under investigation is a diglycidyl ether of bisphenol A (DGEBA) epoxy matrix, which incorporates microcapsules filled with amine‐functionalized polydimethylsiloxane (PDMS‐a), as a new healing agent, combined with microcapsules filled with triethylenetetramine (TETA). The fracture toughness (KIC) and healing efficiency of these systems were measured using tapered double‐cantilever beam specimens. Fractographic analysis shows the rupture of microcapsules and release of the healing agent, inducing a change in the mirror‐like fracture plane morphology of neat epoxy and healing of cracks. It was also observed that PDMS‐a reduces the stiffness of the epoxy matrix, resulting in greater energy release rate (UIC) values. The values of self‐healing efficiency for systems healed for 48 h at room temperature varied from 0.82 to 1.0 (η, from KIC values) and from 1.0 to 1.4 (η’, considering UIC values). Specimens healed at 80°C containing 2.5 wt% of microcapsules filled with PDMS‐a and TETA achieved η = 1.1 and η’ = 2.0, indicating a highly efficient self‐healing process. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47627.