Microencapsulation of Isophorone Diisocyanate With Silica Shell

Abstract

In several studies, Isophorone diisocyanate (IPDI), a monomeric aliphatic diisocyanate, has been microencapsulated with various polymeric shells for self-healing purposes in polymer-based materials. In this study, for the first time, isophorone diisocyanate was microencapsulated with silica shell via interfacial polycondensation of a silica precursor (TEOS). The shell materials of the IPDI-loaded microcapsules reported in the literature are polymeric (organic). It is known from the literature that silica shell can chemically and physically bonded to cementitious matrices, allowing the microcapsules to remain stable for years without deterioration. Essential parameters such as the amounts of core material (IPDI), shell-forming material, and surfactant as well as the stirring speeds were investigated through yield, optical microscopy, SEM, TGA, and FTIR analyses. Promising results were obtained in the process of microencapsulation of isophorone diisocyanate with silica shell. The optimum core material/shell-forming material, oil phase/aqueous phase, and surfactant/oil ratios were found to be 1.0, 0.18, and 0.08, respectively.