Epoxy Paints and Coatings.
Epoxy Oilserv Nigeria Limited Supplies high quality range of epoxy paints and Coatings, epoxy paints and epoxy floor coatings, (we apply epoxy floor coatings also) coatings are generally packaged in two parts that are mixed prior to application.
Chemistry of Epoxy Paints and epoxy floor Coatings
The two parts consist of 1) an epoxy resin that is cross-linked with 2) a co-reactant or hardener. Epoxy paints and 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
Steel, Concrete, etc. Is it suitable for the coating and the environmental exposure?
Are the requirements adequate?
Normally above 55ºF for the first 72 hours of drying, and at least 5ºF above the dew point.
Normally below 85% required.
Is the coating suitable for the conditions it will be exposed to?
What performance characteristics will the coating be exposed to? (i.e. abrasion, flexibility, heat resistance, etc.)
Will it be required and within what time frame?
Application Methods of Epoxy Paints and epoxy floor Coatings
Is the coating designed for the specific method? (i.e. spray, brush, roll, squeegee/trowel)
Cost per mil per square foot per year of life expectancy.
Is the coating able to comply with the specifications?
Movement It is very important to have fresh air circulating over the surface during drying.
Critical, especially during cold weather and high humidity.
Do not exceed. Coating may appear usable but will exhibit poor performance.
Be aware that some epoxies yellow more than others. More noticeable in whites and off-whites.
Will odor be a concern in or around the application area? Solvent based, water-based, high solids epoxies.
Literature Of Epoxy paints and Coatings
Epoxy paints and coatings are used because they offer outstanding chemical and water resistance, are extremely durable and have excellent adhesion to a variety of substrates. They are two-pack paints which mean they consist of two components (a base and a curing agent) which must be mixed together in the right ratios prior to application.
One disadvantage of epoxy based products is that they have a poor resistance to ultra-violet light. In real terms this means that if left in direct sunlight for long periods epoxy products yellow and a white residue will form on the paint surface- a process known as chalking. This is purely a cosmetic issue and does not interfere with the chemistry of the paint, but can easily be avoided by over-coating the epoxy with a suitable topcoat.
As mentioned previously, epoxy products consist of two components that must be mixed together prior to application.
Once the components have been combined they must be applied within a specified time limit- this is known as pot life. Pot life can vary from anything from a couple of minutes to several hours and is heavily dependent on temperature. Once the pot life has been exceeded the epoxy will be too hard and viscous for application to continue.
The best time to re-coat epoxy is before the first coat is fully cured (this varies between products), within 48 hours as a general rule. This ensures that the coats will form a chemical bond as well as a physical bond to each other.
An issue to be aware of when applying epoxys are that they are liable to a phenomenon known as “amine blush”. This is more common during application by airless spray and occurs when the amine molecules in the epoxy react with moisture and carbon dioxide in the air. The result is a white, waxy coating on the paint surface that hinders adhesion of subsequent coats. Amine blush can be prevented by including an induction period (leaving the combined mixture for a short period before application), and by avoiding application in humid conditions or conditions close to the dew point.
The addition of solvents (also known as thinners) to epoxy products is not strictly necessary however in certain conditions can aid application. Extra solvents will allow the product to flow out better, and will aid penetration into substrates such as wood and concrete.
If you have any questions regarding Epoxy Oilserv Limited range of epoxy paints and epoxy floor coatings please contact us.