What’s the Difference Between Epoxy and Polyester Resins? A blog which educates users on the differences between these two epoxy products.

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What’s the Difference Between Epoxy and Polyester Resins?

Epoxy resins are different than other kinds of resin because they have a much stronger bond. They harden at room temperature and don’t require any help from outside sources to do so. Epoxies can also fill in larger gaps between materials because they are thicker, which means that you can use them on surfaces that may not be perfectly flat or smooth. An epoxy is probably what you need if your project requires a strong hold between two pieces or if you need to fill in a gap.

Polyester resins are commonly used with fiberglass, but they can be used by themselves as well. Because polyester resins do not have the same strong bonding qualities that epoxies do, they are often used with fillers to improve their strength. While polyester resins aren’t as strong as epoxies, they do have other qualities that make them unique. For example, polyesters aren’t affected by UV rays like epoxies are and can be worked on longer before they cure (approximately 20 minutes). Also, polyesters can be used to repair gel coats and plastics, whereas epoxies cannot. Polyesters also have a lower cost than epoxies.

Epoxy resins are the most cost-effective way to protect and enhance your flooring, but there are different types of epoxy available. It can be difficult to know which one is right for your needs. Two of the most common types of epoxy are Polyester and Epoxy.


Polyester resins are typically used in the marine industry because they are water resistant. They are also used in surfboards and fiberglass boats. Polyester is a cheaper alternative to epoxy resin, but it requires a catalyst to cure properly. Because it is more elastic than epoxy, it has some disadvantageous qualities including UV resistance and adhesion. Polyester resin will also yellow over time when exposed to the sun and discolor from exposure to gasoline.


Epoxies come in several forms and have many uses, from woodworking to flooring to crafts. They have high tensile strength and resist impact damage well. Epoxies have strong adhesive qualities and bond well with surfaces other than metal or plastic. Because they don’t require a catalyst, they do not shrink as much during the curing process and form a hard, durable surface that is resistant to chemicals, heat, cold, water and solvents. An epoxy-based

Epoxy and polyester resin are both used for woodworking, but what are the differences between the two? Epoxy is thinner than polyester resin and does not yellow as much when exposed to sunlight. It is also more heat-resistant and bonds better with wood, fiberglass, and some metals.

Polyester resin, on the other hand, is thicker than epoxy. This means polyester resin takes longer to soak into the wood grain. It also tends to cause more bubbles after application. Polyester resin is less expensive than epoxy and easier to find in local hardware stores. Because of its fast curing time, it is also better suited for projects that need a quick turnaround time.

I would recommend using epoxy especially if you want a high-quality finish. I used polyester resin for my first wooden surfboard project because it was cheaper and easier to find at my local hardware store.

Epoxy and polyester resins, while similar in nature, are very different. Both materials are thermosetting epoxies, meaning once the material is cured it cannot be remelted. Epoxy resin is a two-part system, consisting of a resin and a hardener. These two components are mixed and applied to a surface.

Polyester resin is one component and does not require the addition of a catalyst or hardener. Polyester resin is either catalyzed by adding MEKP (methyl ethyl ketone peroxide) or can be thickened with silica or aluminum powder.

Epoxy resins are most commonly used in boat building and repair due to their superior bonding ability. Polyester resins have traditionally been used in the construction of fiberglass parts such as auto bodies, boats and bathtubs due to their lower cost and ease of use. Epoxy resins are also used in the production of some carbon fibers and composite materials such as those used in aircraft wings.

Epoxy and polyester resins are the two most widely used resin compositions in the industry, but they have a lot of differences. So, what is the difference between epoxy and polyester resins?

Epoxy resin is more expensive than polyester resin. This is one of the main differences between these two products. Epoxy has a stronger bond than polyester resin and it’s also more resistant to heat. Epoxy is generally used for industrial purposes because it has better waterproofing properties. Polyester resin is cheaper, less toxic and easier to use than epoxy.

What Is Epoxy Resin?

Epoxy is a synthetic material that’s widely used in adhesives and coatings. Epoxies are thermosetting polymer materials that start as liquid but cure into solid plastic materials through a chemical reaction with a curing agent. Epoxies can be cured at room temperature or with heat. They’re highly durable, moisture-resistant and strong materials that can be applied to almost any surface, including metal, fiberglass, wood and concrete.

Epoxy has many uses in various industries, like construction, electronics and automotive repair. It’s also frequently used as an adhesive or as a coating for floors and

When starting a project involving epoxy, you will often find that there are two types available to choose from: polyester resin and epoxy resin. The differences between these resins are important to understand when determining which product is best for your project.

Polyester resin is the most commonly used resin for most fiberglass boat building. It is also used for laminating, bonding, coating and casting with glass fibers, carbon fibers and aramid fibers. Polyester resins have a relatively low cost and are easy to use as well as having excellent mechanical properties over a wide temperature range. The main disadvantage of polyester resins is that they are sensitive to moisture during the curing process which can lead to poor quality parts if care isn’t taken. Another disadvantage of polyester resins is that they contain styrene which has been classified as a possible carcinogen by the EPA, OSHA and IARC. These disadvantages make polyester resins inappropriate for certain applications such as potable water tanks where contact with water is expected or applications where health concerns are an issue.

Epoxy resins on the other hand offer excellent chemical resistance and adhesive qualities while not being sensitive to moisture during the curing process. Epoxies also offer a much longer pot life (

Epoxy and polyester resins are commonly used in a wide range of consumer and industrial products. Historically, epoxy resins have been the more expensive of the two materials but have a higher performance profile. This has led to their use in more demanding applications such as aircraft, wind turbines, bridge building and electronic encapsulation. Epoxies also offer better chemical resistance than polyesters, making them ideal for paints and coatings. The lower cost of polyester resins has historically made them the material of choice for general purpose consumer products such as boats, bathtubs, showers and countertops, as well as industrial products such as tanks, piping systems and outdoor furniture

More recently however, the price differential between epoxy and polyester resins has narrowed due to changes in manufacturing processes which have reduced epoxy resin production costs. This has led to a significant increase in the use of epoxies in lower-end applications such as boat building where they are now displacing traditional fiberglass-polyester composites.

The types of epoxy and polyester resins offered by Clear Casting Resins are:

Epoxy Resin – Polyurethane Resin

Clear Casting Resin – Clear Coating Epoxy

Polyester Laminating Resin

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