Epoxy resin is celebrated for its remarkable strength and glass-like clarity, often drawing comparisons to glass due to its translucent appearance.

However, beyond looks, how does epoxy resin compare to glass in terms of other properties? Glass is known for its fragility; does epoxy resin exhibit similar characteristics?

In this article, we'll take a look at the differences between epoxy and glass, particularly focusing on their strengths and how each material responds to various types of stress without yielding or fracturing.

Is Resin Brittle Like Glass?

No, epoxy resin does not shatter like glass does.

Glass, known for its brittleness, fractures abruptly and sharply when broken. In contrast, epoxy resin is a plastic polymer that generally exhibits more flexibility and less brittleness.

Once epoxy resin has cured, it becomes a solid material capable of enduring some degree of bending or flexing without breaking. When applied to a surface, the incredible durability of epoxy enhances the overall resilience of the substrate it has bonded to.

However, it is important to note that epoxy can still crack or chip under certain conditions, particularly if the pour is thin or if mistakes were made during the mixing or pouring phases.

Subpar Epoxy Resin Can Be a Major Issue

Low-quality resin, which are often found on 3rd party marketplaces like Amazon and eBay, may be more brittle and prone to cracking. Although these cracks can sometimes resemble shattering, especially if the resin is stressed or struck with significant force, it typically does not break as dramatically or hazardously as glass.

For the most part, while epoxy resin can experience cracking or chipping in specific situations, it does not shatter in the same manner as glass. This is due to its inherent material properties, which provide greater flexibility and resistance to sudden breaking.

So Epoxy Isn't Brittle Like Glass, But It Is Transparent Like Glass. Why?

The answer to this gets more and more technical the closer you get to the truth. We'll try to give a basic overview.

Light Can Be Absorbed by Electrons

As light attempts to pass through a material, the subatomic particles within the material try to absorb it. However, they can only absorb light at certain frequencies. If the light doesn’t match these frequencies, it will pass through the material without being absorbed.

Similarly, the components of epoxy, like those of glass, do not absorb the wavelengths that constitute visible light, allowing light to pass through unobstructed.

The Quality of the Epoxy Affects Its Transparency

The clarity of cured epoxy resin stems from its purity and the absence of impurities or colorants in its basic makeup. High-quality epoxy resins are meticulously produced to reduce any cloudiness or discoloration, ensuring that the final product is as transparent as possible. Additionally, the smooth and even surface of cured epoxy helps minimize the scattering of light, allowing it to transmit similarly to glass.

It's worth acknoledging, however, that while epoxy resin is naturally transparent, its clarity is influenced by several factors. These factors include the quality of the resin, the precision of the mixing ratio between the resin and hardener, and the conditions under which it cures. Any variation in these aspects can introduce bubbles, haziness, or cloudiness, compromising the resin's glass-like transparency.

In the end, with its inherent properties, epoxy resin has become an excellent option for applications requiring a clear, glass-like appearance, such as in encapsulations, coatings, and artistic projects, but it offers the added advantage of not being as brittle as glass.

All Materials Have Weaknesses, So What Are Epoxy's?

Epoxy may be incredibly resilient to shattering, but it's not impervious to all other forms of stress and damage. Two weaknesses epoxy has are to consistent UV radiation and to powerful solvents.

Let's go over them.

Weakness #1: UV Radiation

UV radiation is a common vulnerability among plastics and polymers, including epoxy, which is one of the many polymers that are affected by it.

Sunlight is the primary source of UV radiation. While the earth's ozone layer absorbs much of the harmful UV radiation from the sun, a significant amount still penetrates the atmosphere, affecting both epoxy resin (and people!).

Regular exposure to UV radiation can lead to the gradual yellowing of epoxy. Additionally, if the epoxy is of lower quality, it may also become more brittle or start to develop internal cracks.

Avoiding the Issue

There are a few methods you can employ to protect your epoxy from sunlight damage.

One effective strategy is to provide physical shelter for your epoxy-coated items. This is particularly useful if you want to maintain a clear finish on outdoor projects. Positioning your project under an overhang, in a shaded spot, or beneath a protective covering can significantly help preserve the appearance of your epoxy finish. For indoor projects, direct sunlight exposure is usually less of a concern, as they are often shielded from direct sunlight.

Another option is to incorporate epoxy powder pigments into your resin. These pigments are derived from mica minerals, known for their insolubility and reflectiveness. Once processed into a fine powder and mixed into the epoxy resin, these pigments help reflect UV radiation away from the resin, minimizing or even preventing the yellowing effects often caused by UV exposure.

Weakness #2: Powerful Solvents

Another vulnerability of epoxy is its sensitivity to potent solvents. Powerful chemicals, such as lacquer thinner and acetone, can soften or dissolve epoxy resin.

While these chemicals are sometimes used intentionally to repair a damaged epoxy finish or to completely remove epoxy when necessary, there are far simpler and safer methods for cleaning epoxy surfaces.

Epoxy's Glasslike Appearance Does Not Diminish Its Incredible Strength

Ultimately, epoxy resin is undeniably an incredibly resilient material. At first glance, it might resemble glass with its clear, highly transparent finish, yet it is much stronger and significantly less brittle.

This resilience makes epoxy an outstanding choice for sealing a variety of surface materials. Whether it's wood, granite, marble, laminate, or something else, all substrates greatly benefit from a protective epoxy resin coating. Moreover, epoxy is easier to maintain compared to many other sealants, adding to its practicality as a protective finish.

Primaloc Epoxy: Premium Epoxy for Premium Results

With our premium Bar & Table Top Epoxy and our Deep Pour Epoxy, Primaloc gets the job done. Our epoxy resins are premium-grade, with high performance in every category, including:

• Unmatched Strength: A Primaloc finish won't buckle, even under high pressure.
• Long-Lasting Resilience: Primaloc epoxy lasts for many years with minimal care, and can endure high-traffic environments with ease.
• A Crystal-Clear Coating: With its pristine, transparent appearance, looking at a cured Primaloc coating is like peering through a window.

Epoxy resin can be beautiful, strong, and long-lasting—which is why you shouldn't compromise on quality. With Primaloc Epoxy Resin, you get the ultimate finish in durability and visual appeal.

Protect your surfaces by giving them a rock-solid epoxy finish. Choose strong. Choose reliable. Choose Primaloc.