T. Siva

Graphene ink as a corrosion inhibiting blanket for iron in an aggressive chloride environment

Corrosion resistance of iron (Fe) was achieved by coating it with a reduced graphene oxide ink. The Fe surface with the graphene oxide ink coating exhibited improved corrosion resistance in an aggressive chloride environment, which is attributed to the excellent barrier property of graphene. The advantage of this method is that graphene can be deposited by using a solution process that is easy, reproducible, and can be used to coat objects of any dimensions just like conventional paints or coatings.

Mesoporous silica based reservoir for the active protection of mild steel in an aggressive chloride ion environment

Spherical mesoporous silica (m-SiO2) with well-ordered pores was synthesized by a modified Stober method using CTAB micelles. The as-prepared silica was used as a reservoir to load a corrosion inhibitor. Steel samples that were coated with the inhibitor loaded silica reservoir exhibited improved corrosion resistance compared to the samples without the silica reservoir in an aggressive chloride environment. Localised electrochemical impedance spectroscopy (LEIS) and scanning vibrating electrode technique (SVET) data suggest that inhibitor release is triggered by the local corrosion phenomena, which leads to active protection of the metal.

A smart poly(aniline-formaldehyde) microcapsule based self-healing anticorrosive coating

The effectiveness of linseed oil and mercaptobenzothiazole (MBT) encapsulated poly(aniline-formaldehyde) [PAF] microcapsules was investigated for healing of cracks generated in paint/coatings. Microcapsules were prepared by in situ polymerization of aniline-formaldehyde resin to form a shell over the linseed oil and mercaptobenzothiazole. Characterizations of these capsules were studied by FTIR, TGA, and Scanning Electron Microscopy (SEM). EIS studies of the artificial defect area have shown that the coating containing microcapsules is able to protect steel in neutral media since the impedance values remained at 1.287 × 108 Ω cm2 even after 15 days exposure whereas the coatings without microcapsules lost their protection ability. The self healing ability of the coating containing microcapsules was studied by SVET.

Cationic surfactant assisted synthesis of poly o-methoxy aniline (PoMA) hollow spheres and their self healing performance

Hollow microspheres of poly(o-methoxy aniline) (PoMA) were prepared in a solution of cetyltrimethylammonium bromide (CTAB) using ammonium persulfate (APS) as oxidant. The morphology of the final polymers was characterized by scanning electron and transmission electron microscopic techniques. The microspheres are formed by polymer growth on preformed micelles. The presence of CTAB led to microspheres with a very regular size distribution. The polymer hollow spheres thus synthesized were characterized by FTIR, UV-Vis, TGA and XPS techniques. A study has been made on the corrosion protection performance of mild steel by an epoxy coating containing synthesized PoMA hollow spheres using EIS measurements in 3% NaCl solution. The self-healing ability of the coating was studied by scanning vibrating electrode technique (SVET).