Polymeric vesicles for corrosion control in reinforced mortar: Electrochemical behavior, steel surface analysis and bulk matrix properties

This study reports on the corrosion performance of reinforced mortar in the presence of polyethylene oxide-b-polystyrene (PEO113-b-PS780) vesicles (both “empty” and Ca-containing vesicles). The electrochemical response and microstructural/morphological observations of the steel reinforcement show that the admixed vesicles, especially the Ca-containing ones, increase the steel corrosion resistance. The responsible mechanisms are initially due to enhanced barrier effects, introduced from the presence of the vesicles themselves and are further (after corrosion initiation) related to calcium release from the Ca-containing vesicles, leading to a repair of the steel surface layer.

► Vesicles (especially Ca-containing one) increase corrosion resistance of the steel.
► The admixed vesicles lead to a surface layer with enhanced barrier properties.
► The plausible mechanisms related to calcium release from the vesicles are proposed.