You might have seen videos on Facebook, Instagram, or YouTube about how to make epoxy tables, coasters, or other art projects. But ever wondered what epoxy is?
Epoxy is a type of plastic, a thermosetting polymer. They are known for their exceptional strength, durability, and versatility. It is used as an adhesive or sealant. When two components epoxy resin and hardener are mixed, a chemical reaction occurs between the two, and when applied/poured on a surface, it creates a rigid structure that cannot be melted and reshaped. This irreversible hardening process distinguishes it from thermoplastics, which can be repeatedly melted and reformed. They are highly resistant to many chemicals, including solvents, acids, and alkalis, making them suitable for harsh environments. They have a low molecular weight and exhibit low shrinkage during cure (1%-5%).
Application:
- Polyester epoxies are used as powder coatings for washers, driers, and other “white goods”.
- Fusion Bonded Epoxy Powder Coatings (FBE) are extensively used for corrosion protection of steel pipes and fittings used in the oil and gas industry, potable water transmission pipelines (steel), and concrete reinforcing rebar.
- Widely used as primers to improve the adhesion of automotive and marine paints, especially on metal surfaces where corrosion (rusting) resistance is important.
- Metal cans and containers are often coated with epoxy to prevent rusting, especially for foods like tomatoes that are acidic.
- Used for decorative flooring applications such as terrazzo flooring, chip flooring, and colored aggregate flooring.
Limitations
- When working with uncured resin, a person should be careful, as touching uncured resin with bare hands can lead to skin irritation, potentially including rashes or even allergic reactions. Prolonged or repeated exposure can cause more serious issues like dermatitis, and the fumes can also irritate the respiratory system.
- Change in color, known as yellowing, is a common phenomenon for epoxy materials (even when not exposed to UV radiation) and is often of concern in art and conservation applications.
- Epoxy is generally not biodegradable, but there have been recent advancements in creating recyclable and self-healing epoxy materials, addressing concerns about the environmental impact of thermosets.
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