Encapsulation of linseed oil and linseed oil based alkyd resin by urea formaldehyde shell for self-healing systems

The superiority of the present systems as Linseed oil and its alkyd resin evolves from the utilization of the environmentally friendliness thanks to their film formation by auto-oxidation. The encapsulation of healing agents by means of in-situ polymerization of urea formaldehyde has been studied with the parameters as the amount of surfactant and the rate of stirring. The experimental design has been modeled by using Response Surface Method to investigate the effect of surfactant (poly(vinyl alcohol), PVA) amount and stirring rate effect on the microcapsules (MC) size. Optical microscopy has been utilized to follow the reaction and size change of MCs. The chemical structure, thermal properties and capsule morphology has been illuminated by using FTIR spectroscopy, TGA and SEM analysis, respectively. The capsules obtained have had 51 and 56 μm diameter at high levels of the parameters (60 ml PVA, 1500 rpm stirring rate) and 97 and 261 μm diameter at low levels of the parameters (20 ml PVA, 800 rpm stirring rate) for LO and LO-Alkyd respectively.