Epoxy resin matrix integrating epoxy‐polydimethylsiloxane based self‐healing microcapsules: Healing efficiency, mechanical and thermal stability

Abstract

AbstractEnvironmental factors such as climate change, temperature fluctuations, and mechanical forces hinder long‐term space, transportation, and research missions due to structural damage. We report an innovative system to overcome this problem. The self‐healing structure under examination is an epoxy as a polymeric matrix, which includes microcapsules embedded with epoxy‐polydimethylsiloxane (PDMS), as a healing agent, separately combined by microcapsules embedded with triethylenetetramine (TETA) as a hardener or curing agent. Scanning electron microscopy confirmed the presence and size of the microcapsules. It was shown that the rough appearance of microcapsules improves mechanical bonding. The diameter of microcapsules varied between 40 and 200 μm, with an average diameter of ~100 μm. The information of microcapsules and their structures were scrutinized through Fourier transformed infrared spectroscopy for chemical structure confirmation. It was determined that epoxy‐PDMS practical liquids have been effectively encapsulated. The thermal performance of the microcapsules was investigated utilizing thermogravimetric analysis. The results showed that the microcapsules have thermal stability up to 220°C without degradation and decomposition. Additionally, the flexural test was used to evaluate the samples manually scratched with blade and compared with the pure epoxy sample. The results showed the sample containing 15% microcapsules has 105% recovery efficiency after 55 h.