Self-Healing of Epoxy-Loaded Halloysite Nanotubes/Polysulfone Nanocomposite Membrane

Self-healing composites are smart materials that can be fabricated through the dispersion of tubular nanofillers loaded with appropriate healing agents in a polymeric matrix. In this study, polysulfone (PSf) containing epoxy-loaded halloysite nanotubes (e-HNTs) were successfully fabricated via non-induced phase separation (NIPS) method at varying concentrations. Fourier Transform Spectroscopy (FTIR) analysis showed that epoxy (healing agent) and amine (hardener) were successfully loaded into the lumen of the HNT through the observed functional groups of the epoxy system along the HNT spectrum. The tensile strength of the loaded membranes compared to their unloaded counterpart slightly decreased due to the possible embrittlement of the unreacted epoxy. However, the membranes with epoxy-loaded HNTs garnered lower wettability on average due to the hydrophobic character of the epoxy system, which is a preferable trait for smart coatings. The self-healing capability of the membranes with 5% filler (loaded and unloaded) was investigated by scratch test and Scanning Electron Microscopy (SEM). The result revealed a high tendency of healing for the epoxy-infused nanocomposite film.