Guide to Bonding Agents

See Bonding Agents for information on individual products

Types of bonding agents:

Epoxy: Generally considered the best for high bond strength and stress transfer. (Dayton Superior J-58)
Non-reemulsifiable: Generally an acrylic latex emulsion. (Dayton Superior J-40)
Reemulsifiable: Generally a polyvinyl acetate (PVA) emulsion. (Dayton Superior J-41 or J-42)

Always use a non-reemulsifiable or epoxy bonding agent when the application is outside or anywhere it frequently comes in contact with moisture.

Use a reemulsifiable bonding agent only when the application is inside or not routinely exposed to moisture. These types of bonding agents can lose bond and fail if exposed to moisture over a period of time. These bonding agents can be allowed to dry to the touch and then rewet when the concrete or mortar is applied, providing more "open" or working time for the applicator.

Epoxy bonding agents and some non reemulsifiable bonding agents must not be allowed to totally dry to the touch before the concrete or mortar is applied. If this happens, the bonding agent can become a bondbreaker and the bond will fail. If the bonding agent dries before the concrete/mortar is placed, the bonding agent must be lightly abraded, solvent wiped, then reapplied.

Acrylic latex emulsion and PVA emulsions can be mixed with Portland cement to create a scrub coat for use as a bonding agent. This is quite common and, when used, they should be scrubbed into the concrete with brushes immediately before applying the topping or patching material.

Acrylic latex emulsions and PVA emulsions are also used as additives for cementitious products such as patching compounds, grouts, mortars, etc. As an additive, these products not only promote a strong bond, but they also improve the long-term durability, flexural and tensile strengths and resistance to cracking of the finished product.