Investigating on Release Behavior of pH-responding Melamine Formaldehyde Microcapsules

In this study, microcapsules with melamine formaldehyde as a shell and ethylene glycol as a core were synthesized by in-situ polymerization and the characteristics of these capsules were studied by Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). The pH-triggered release of phenolphthalein from the capsules was evidenced using UV-visible spectroscopy. The morphological study showed the microcapsules are of spherical nature with average diameter 5 μm. According to the results, with increasing pH value, the releasing rate of phenolphthalein from capsules increases. Therefore, the capsules are suitable for using in alkaline environments and can be a good candidate for reducing the rate of the corrosion because of a controlled release of a corrosion inhibitor, as demanded by the presence of the cathodic reactions.

Keywords:

Microcapsule , Poly (melamine-formaldehyde) , pH-triggered release