Why we need to use a concrete bonding agent? It is because the cement within a concrete mix doesn't contain any natural bonding agents – so when fresh concrete is added on top of an existing layer of concrete, the two won't join together. The new concrete will simply sit on top as a separate layer once cured. Bonding agent is known as a high solids, water-based emulsion admixture suitable for modifying Portland cement compositions. It is also designed to serves as a bonding agent between new and hardened concrete. With our Stringent Quality Control, Bond Ace products are tested by local SIRIM and complying EN standards.