The effect of silica-modified carbon nanotubes additive to alkyd enamel coating on adhesion, corrosion resistance and bonding of reinforcement with cement

In this paper, the effect of carbon nanotubes coated with silicon dioxide, used as a filler in alkyd enamel PF-115, on the adhesion strength of the modified alkyd enamel paint to steel reinforcement and on the adhesion of reinforcement coated with modified alkyd paint to concrete was investigated. The adhesive tape method (ASTM D3359 Standard) was used to study the adhesion strength. To test the effect of the corrosion resistance of the coating on the adhesion strength between the coated reinforcement and concrete, the samples were subjected to a preliminary accelerated corrosion process in a sodium chloride solution under the influence of a direct electric current of 0.5 A, after which pullout tests were carried out. The results showed that with an increase in the nanofiller content, the adhesion strength decreases insignificantly, and the force for pulling out reinforcement from concrete increases for the coated samples with an increase in the nanofiller concentration to 0.349 wt. %, after which it begins to decrease. The improvement in the overall corrosion resistance characteristics of the coating after the application of a modified alkyd enamel used as a protective coating for steel reinforcement containing carbon nanotubes with silica with a concentration of 0.349 wt. % was established.