POLYMER CEMENT MORTAR IN REPAIR ACTION ON CORROSION RATES

Tânia Dias, Orlando Pereira, Elsa Pereira and Maria Sofia Ribeiro

ABSTRACT

The action of styrene-butadiene and acrylic-styrene polymer modifiers on the corrosion rate of steel embedded in carbonated cement mortar were evaluated by corrosion current intensity measurements in wetting-drying cycles. The results of polymer cement mortars were compared with those of an unmodified cement mortar and discussed. These results were additionally confronted with the air content, water absorption, resistance to carbonation and electrical resistivity. The microstructure of the corrosion products was characterised by scanning electron microscopy and energy dispersive X-ray analysis. Results confirmed a noticeable reduction in the corrosion rate of steel rebars embedded in carbonated PCMs comparatively to unmodified CM.

KEYWORDS: Polymer cement mortar; Polymer dispersion; Corrosion; Carbonation; Repair mortar.