Langmuir, Vol.35, No.24, 7871-7878, 2019
Dispersion of Poly(urea-formaldehyde)-Based Microcapsules for Self-Healing and Anticorrosion Applications
An effective dispersant, oleyl phosphate (OP), for the dispersion of poly(urea-formaldehyde)-based micro capsules in a typical epoxy coating material is proposed. Based on electron microscopy observations and rheological and mechanical characterizations, it is observed that the addition of merely 0.5 wt % of OP is sufficient to obtain good dispersion of the microcapsules in the epoxy. In the self healing and anticorrosion experiments, a microcapsule content of at least 15 wt % is required to efficiently restore the epoxy matrix and provide corrosion protection to underlying low carbon steel when the particles are not dispersed; however, the amount of microcapsules required to obtain good self healing and anticorrosion efficiencies can be greatly reduced to only 5 wt % when the microcapsules are dispersed by OP.