Control and mitigation of MIC by silver species hosted in microporous materials

A. M. PEREYRA; MARIO S. MORENO; MARCIA SOARES LUTTERBACH; E. I. BASALDELLA

Río de Janeiro

Congreso; 21st INTERNATIONAL CORROSION CONGRESS & 8th INTERNATIONAL CORROSION MEETING; 2021

INTERCORR-ABRACO

This work introduces the use of nanostructured zeolite/silver composite as additive to provide biocidal properties to epoxy coating formulations. The zeolite network would stabilize the silver species at a nanometric level allowing long-lasting antibacterial activity. Silver nanoparticles dispersed onto micrometer-sized crystals of A-type zeolite were prepared by reduction methods applied to a Ag+-exchanged zeolite. TEM, XRD and UV-Vis analyses confirmed the presence of rounded crystalline nanoparticles, homogeneously dispersed on the outer surface of the zeolite crystals: Ag0 and Ag2O nanoparticles coexisting with non-crystalline clusters Agmn+ and silver cations hosted inside the porous structure. The microbiological activity against P. aeruginosa of polyamide epoxy coatings formulated with the nanocomposite was statistically measured by cell quantification. Inhibition halo was not observed. This fact suggests that, at the composite concentrations used, silver species leaching from the coating did not occur and the mechanism of inhibition should be exerted via direct contact of the coating with the bacterial cells. The coatings formulated with the silver composite could be effective for controlling the corrosive action caused by P. aeruginosa, minimizing the different reasons leading to corrosion.