Epoxy Floor Coverings

What is Epoxy?
Epoxy is a term used for a family of thermosetting resins that are capable of forming tight cross-linked polymer structures characterized by toughness, strong adhesion, and low skrinkage. Another great benefit of Epoxy is that it also forms a very strong film with excellent chemical resistance.

Epoxy coatings are used because of their outstanding chemical resistance, durability, low porosity and strong bond strength. There are two classes of epoxy polymers used as coatings: aromatic and aliphatic. Aromatic resins should not be used for exterior applications because they yellow and degrade over time. Aliphatic resins have good resistance to UV radiation and can be used on either interior or exterior applications.

Resins are also classified as solvent-based, emulsion, or 100% solids. The solvents in resins evaporate during the curing cycle, can be smelly for a period of time, and in some cases are a fire hazard (red label solvents are not allowed in most building applications). Emulsion resins contain primarily water as the carrier with small amounts of solvent. These materials are nonflammable, have much less odor, and are recommended for interior use. Resins that are 100% solids refer to the fact that all material in the resin is used in the curing phase and become solid epoxy.

The other type of resin that is becoming increasingly popular is emulsion VOC resin. It is water-based and can be purchased as a one- or two- part resin. Certain resins in this class of material can have good moisture vapor transmission (MVT) characteristics also.

These emulsion two part epoxies consist of a 'base' and a 'curing' agent. The two components are mixed in a certain ratio. A chemical reaction occurs between the two parts generating heat (exotherm) and hardening the mixture into an inert, hard 'plastic'. These epoxies are expensive, but there are ways to 'water down' the epoxies with less expensive solvents an/or non-solvent thinners. These cheaper, diluted epoxies do not perform as well as the more expensive, unaltered epoxies. Diluted epoxies are especially common with floor epoxies where pricing pressures are especially strong. To a degree you do get what you pay for. A common non-solvent thinner is a chemical known as nonyl phenol. It would be wise to review your epoxy's MSDS for references to nonyl phenol.