Epoxy coatings are generally packaged in two parts that are mixed prior to application. The two parts consist of 1) an epoxy resin which is cross-linked with 2) a co-reactant or hardener. Epoxy coatings are formulated based upon the performance requirements for the end product. When properly catalyzed and applied, epoxies produce a hard, chemical and solvent resistant finish. They are typically used on concrete and steel to give resistance to water, alkali and acids. It is the specific selection and combination of the epoxy component and the hardener component that determines the final characteristics and suitability of the epoxy coating for a given environment.

  

Key Issues to Consider During Selection and Use of Epoxies

Substrate Types

Steel, Concrete, etc. Is it suitable for the coating and the environmental exposure?

 

Surface Prep

Are the requirements adequate?  


Temperature/Variations

Normally above 55ºF for the first 72 hours of drying, and at least 5ºF above the dew point.

 

Humidity

Normally below 85% required.

 

Environmental Exposure

Is the coating suitable for the conditions it will be exposed to?

 

Performance Requirements

What performance characteristics will the coating be exposed to? (i.e. abrasion, flexibility, heat resistance, etc.)

 

Recoatability

Will it be required and within what time frame?

 

Application Methods

Is the coating designed for the specific method? (i.e. spray, brush, roll, squeegee/trowel)

 

Cost/Value Considerations

Cost per mil per square foot per year of life expectancy.

 

Film Build

Is the coating able to comply with the specifications?

 

Air

Movement It is very important to have fresh air circulating over the surface during drying.

 

Induction Time

Critical, especially during cold weather and high humidity.

 

Pot Life

Do not exceed. Coating may appear usable but will exhibit poor performance.

 

Aesthetics

Be aware that some epoxies yellow more than others. More noticeable in whites and off-whites.

 

Odor

Will odor be a concern in or around the application area? Solvent based, water-based, high solids epoxies.

  

 

Epoxy Coatings Sections

 

Epoxy Coatings Guide (.pdf)