The Waterborne Symposium

Abstract
Factors Affecting Sealer Performance on Concrete
Co-author: Gary Johnson

It is often assumed that solventbased sealers give better performance than waterborne formulations on concrete because the solventbased sealers are assumed to penetrate better into the concrete matrix.  In practice, it can be difficult to measure actual penetration of a sealer into concrete as dyes and colorants used to highlight the sealer may show different migration properties than the polymeric binder.  Confocal Raman spectroscopy mapping has been used to map the penetration depth of solventbased, 100% solids, and waterborne sealers that employ acrylic and epoxy binders.  This mapping shows that neither solventbased nor waterborne formulations showed any significant penetration into the concrete substrate beyond the first few microns of the open surface.  A study was also conducted using a model waterborne acrylic sealer formulation to determine whether additives might influence the penetration of the sealer into the concrete and other factors that could affect the performance of the waterborne coating.  This work has shown that the addition of anti-foaming, coalescing surfactants can improve the protective properties of the coating by improving air release and increasing film network formation at the concrete surface.