Epoxy vs Polyester Resin: Which Is Better For My Project?

Resin is a vital component in fibreglass projects, acting as a strong and reliable binding solution that holds the glass fibres together. Therefore, choosing the right resin for your next project can be the difference between a long-lasting and hardwearing finish or one that gradually disintegrates over time.

Epoxy resin and polyester resin are among the industry's most popular resins - and the ones that you need to consider most during your latest project. However, both come with their own individual advantages, unique properties and compelling characteristics to weigh up before you decide which is better: epoxy resin or polyester resin?

Whether you're making iridescent resin art and jewellery or you're in the marine, boat building or floor coating trade, resin either serves an aesthetic or a practical purpose as its primary function. You can either create vibrant decorative pieces such as a wide range of resin artwork, including resin coffee tables, pendants, coasters, keychains, trays and household ornaments.

Alternatively, resins can be employed more generally to seal cracks, create waterproof flooring and bolster concrete, or to complete repair, bonding and barrier work in construction projects. Resin is also used in the marine industry to coat, seal, fill and bond a range of materials very effectively.

There are a multitude of vital qualities that pour out from both epoxy and polyester resin. On the one hand, there's strength, chemical resistance and high adherence. On the other, there's cost-effectiveness, fast-curing and easy-to-use attributes that you'll want to weigh up. So, which resin is better for your project?

In our latest blog, Fibreglass Supplies will compare epoxy resin and polyester resin so you can make an informed decision before you click buy. From budget-conscious projects and jobs that require a quick turnaround to the purest of hobbyist pursuits, discover which resin is the very best for you today.

Advantages Of Epoxy Resin

• High Strength & Hardwearing - Epoxy resin will form an impressively strong, impact-resistant and low breakage bond that is superior to polyester resin.
• Astonishing Adhesion - Forms a very powerful bond with a reliable structural hold on a wide range of materials, including wood, metal, glass, stone, concrete and composites.
• High-Gloss & High-Clarity - Produces a high-gloss and crystal clear finish to add stunning aesthetic appeal in resin art, jewellery, furniture and homeware projects. Why not add a lasting colour pigment to your resin to create unique and creative visual styles with Fibreglass Supplies today?
• Brilliant Water & Moisture Resistance - The waterproof properties of epoxy resin will create a solid seal against water ingress to protect your project from deteriorating. These qualities also transfer well into the marine and boating industry.
• Corrosion & Chemical Resistance - Does your project involve exposure to chemicals, oils, solvents or even acids? Epoxy resin is ideal for industrial coatings, floorings and protective linings.
• Slow Curing Time - Great if you're working on a difficult project that requires a long working time. After mixing epoxy, there's a prolonged period of time where it will remain workable and malleable. If you want to avoid mistakes or need more flexibility in longer-term projects, choose epoxy today.
• Dimensionally Stable - Epoxy resin cures with little shrinkage which therefore makes it suitable for very precise moulds, casting and laminations.
• Heat & Impact Resistance - Won't break down easily under reasonable heat and high-impact exposure. Ideal for the aeroplane or automotive industries.

Advantages Of Polyester Resin

• Simple Sanding & Shaping - Once fully cured, it's much easier and simpler to shape and sand polyester resin than epoxy. This makes it ideal for removing any imperfections that may have formed during the curing process.
• Solid UV Resistance - Polyester resin is more UV resistant than epoxy owing to its chemical structure, and also less prone to yellowing and discolouration. This makes polyester resin less vulnerable to degradation caused by sun exposure.
• Decent Fibreglass Adhesion - Forms a good quality bond to existing fibreglass surfaces when properly prepared.
• Cost-Effective - If you're looking for a more affordable choice than epoxy resin, then polyester will be your best option. Ideal if you're looking to cut costs or your project is more limited by budgetary restrictions.
• Quick Curing Time - Suitable for fast, simple and straightforward projects. Polyester resin is ideal for any job that has a fast turnaround as it sets and hardens quickly when compared to slower-curing epoxy resins.
• Cracking & Shrinking Resistance - Holds its shape well with low shrinkage once cured. This improves the strength profile of polyester resin and it can even be combined with fibreglass fibres for additional reinforcement.

Epoxy Or Polyester Resin - Which Is Better?

The most suitable resin for you will ultimately be determined by your project requirements. If you need high-performance properties and a premium-grade finish then epoxy resin will usually do the job. Epoxy resin is much stronger and more long-lasting than polyester resin which makes it far more suited to structural work, repair jobs and harsh environments. However, polyester resin is less expensive but faster to cure and easier to sand and shape - all properties that align with more straightforward applications or larger-scale projects. Browse our complete Resins range at Fibreglass Supplies today!