Microcapsules containing isophorone diisocyanate (IPDI) as healing agents for using in self-healing polymers have been successfully prepared via interfacial polymerization of polyurethane (PU). Microcapsules were manufactured using different polyols including 1,4-butandiol, 1,6-hexanediol and glycerol. The fabrication of PU prepolymer and microencapsulation of IPDI were proved by Fourier transform infrared (FTIR) and thermo-gravimetric analysis (TGA). High yields of IPDI/PU microcapsules were obtained using 1,4-butandiol and 1,6-hexanediol as polyol monomers as determined by TGA. Scanning electron microscopy (SEM) showed synthesis of smooth spherical microcapsules of 1.7 and 3 mu m in diameter using 1,4-butandiol and 1,6-hexanediol as polyol, respectively. (C) 2015 Elsevier B.V. All rights reserved.