Here at Anchor Fixings, we understand the importance of providing the most effective products and materials so everything runs smoothly on site. Epoxy resins are the best option if the installation is critical or structural.
We’ve put together this guide to epoxy chemical resins, including their many applications and benefits, to help you decide whether this is the best product for your fixing application. Here’s what you’ll find in this guide:
Epoxy is a type of chemical resin, which is the overall term for the different types of resin available. These include polyester resin, epoxy acrylate resin, vinylester resin and pure epoxy resin.
All of these have different applications so it’s important to make sure the resin you choose is the most appropriate for your application.
Epoxy resins are a group of prepolymers and polymers that contain epoxides, which react with the hardeners or curing agents added.
The chemical process that takes place is referred to as curing, where the previously soft epoxy is converted into a stiff material. This hardened epoxy is incredibly waterproof, which is why it is widely used in the production of coatings and waterproofing.
At Anchor Fixings, we stock the Buffalo brand of resins, which are manufactured to a consistently high specification. Among this range are two epoxy resins, Buffalo EPSF (Epoxy Acrylate) and Buffalo PUR (Pure Epoxy).
Buffalo EPSF Epoxy Acrylate
Buffalo EPSF is an epoxy acrylate designed as a fast-curing resin fixing anchor for high loads and medium loads and is particularly advantageous for fixings in damp environments or with chemical exposure.
It can be used with all grades of threaded rod and rebar and is also suitable for bolts, posts, studs and anchors. EPSF is great for use in both dry and wet concrete applications, including those that are load bearing.
Buffalo PUR Pure Epoxy
Buffalo PUR is a pure epoxy fixing resin designed for high load bearing applications in concrete. This product is solvent free with virtually no odour, making it safe for use in contained areas. It’s suitable for fixing rebar, threaded studs and anchors to install a massive variety of applications.
It can be used in any kind of solid substrate, for example, concrete, stone, granite, marble or brick. This resin has ETA, WRC and Fire Rated approvals.
Our Buffalo resins are independently tested and have the following certifications/approvals:
Epoxy chemical resin is particularly useful for anchoring applications. It’s used in areas where a higher strength fixing is required, or where a standard ‘manual’ fixing can’t be used.
Buffalo EPSF Epoxy Acrylate Applications:
- Used with all grades of threaded rod and rebar
- Suitable for bolts, posts, studs and anchors
- Used in concrete (both dry and wet), including load bearing applications
- European approval for use in masonry with nylon sleeves
- Good for confined spaces as it’s styrene free
- Can be used indoors as well
Buffalo PUR Pure Epoxy Applications:
- Ideal for diamond drilled holes due to maximum adhesion to smooth surfaces
- Great for rebar usage due to slower gelling action
- Suitable for areas of high chemical exposure (e.g. swimming pools)
- Can be used in wet holes or underwater
- designed for deep embedment and large diameter holes due to its zero shrinkage and longer working times
- For highest ultimate loads
- Can be used in granite, marble etc.
- Good for confined spaces as it’s styrene free
Epoxy resins are combined with a hardener or curing agent in order to achieve polymerisation. It then reacts with the hardener or curing agent and cures into a very strong adhesive, which is why it’s such a popular option for the building and construction industry. It’s imperative that it is mixed thoroughly to ensure an even cure.
Epoxy is thermosetting, which means that it cures depending on the surrounding temperature and once it is cured it cannot be uncured.
Tips for Epoxy Resin installation:
To gain maximum adhesion, ensure the drill hole is cleaned out and free from dust. This can be achieved using a blowout pump. If you have a number of chemical anchors to install, ensure you have all holes drilled, ready for applying resin.
The resin hardens quickly in the nozzle, therefore it is important to install all anchors within as short a timescale as possible.
You can use our chemical resin volume calculator to determine how much you will need for your task.
In the building, construction, manufacturing and engineering industries it’s crucial to use an adhesive that is strong and reliable. It may need to handle heavy loads and maintain structural integrity, and you’ll need a resin that has high bonding strength and resistance to external influences so that you prevent repairs being needed in the future.
Epoxy resin has the highest durability of all the resins, with a longer shelf life, water resistance and chemical resistance.
Let’s look at these properties in more detail:
1. Long shelf life
The resin component has a longer shelf life compared to other resins. This is because the hardener part in the resin is more active. Buffalo EPSF Epoxy Acrylate has a shelf life of 12 months from the manufacture date (Should be stored between +5˚C & +25˚C) and Buffalo PUR Pure Epoxy has a shelf life of 24 months from the manufacture date (Should be stored between +5˚C & +35˚C). This means you can keep the resin on hand for longer and you’ll spend less time and money purchasing more.
2. Superior bonding properties
Epoxy resins can be a more expensive option compared to resin glue or other chemical resins, however, their excellent bonding capabilities surpass all other types of adhesive. The Buffalo PUR resin benefits from zero shrinkage, which maintains the ultimate bond strength.
3. Chemical resistant
Epoxy resins possess higher chemical resistance to common products like acids, alcohol, diesel and oils when compared to other types of resin, hence it’s capable of withstanding extreme conditions.
4. Heat resistant
The strength of epoxy adhesives is degraded at temperatures above 350°F (177 °C), which means it has impressive heat resistance. This is a great benefit, as it’s unlikely that the resin will have to encounter temperatures high enough to affect it. The result is a resin that’s extremely long-lasting and durable.
5. Styrene free with low odour
The Buffalo epoxy resins are designed without styrene, hence they are low-odour and great for use in confined areas.
Resins will react differently depending on the environment, and temperature is a key parameter for the gelling and curing times you can expect. The below examples for Buffalo EPSF and PUR are based on a temperature of 15°C.
Buffalo EPSF Epoxy Acrylate:
Gelling (working) time = 8 minutes
Minimum curing time = 60 minutes (dry concrete) and 120 minutes (wet concrete).
Buffalo PUR Pure Epoxy:
Gelling (working) time = 60 minutes
Minimum curing time = 300 minutes
The longer working time of Pure Epoxy makes it suitable for deeper and larger diameter fixings.
Epoxy resin provides one of the strongest bonds and is considered one of the strongest of all types of adhesives. Not only this, but it’s also excellent at protecting materials such as metal, wood, steel, concrete, glass and some plastics.
The impressive compressive, flexural and peel strength of epoxy resins make them the ideal choice for the building and construction industry.
This is the epoxy’s ability to handle weight, which is especially important if the resin is going to be under heavy loads or used as a structural adhesive.
High loads are possible with Buffalo EPSF, with a compressive strength of 45 N/mm2 and even more so with Buffalo PUR with an impressive compressive strength of 82.48 N/mm2 (test method EN ISO 604 / ASTM 695).
Flexural strength (bend strength)
This refers to the bending strength, which is the epoxy’s ability to resist deformation under a load. Buffalo EPSF has a flexural strength of 15.4 N/mm2 (test method EN ISO 178 / ASTM 790) and Buffalo PUR has a flexural strength of 41.64 N/mm2 (test method EN ISO 178 / ASTM 795).
The high flexural strength of epoxy resins means that once they are cured they will stay in place and will not warp or bend.
This refers to the epoxy’s adhesive bond strength ie. the material’s ability to resist forces that can pull or peel it apart at a predetermined angle and rate.
If an adhesive has a very high peel strength they have a fantastic bond, making it flexible enough to withstand cracking. High peel strength epoxides provide excellent physical strength properties, toughness and resistance to vibration, impact and shock.
Modern health and safety laws dictate that is essential to be aware of the risks and hazards of the products and chemicals you are required to work with. In its liquid form, epoxy resin can irritate the skin and eyes and can be the cause of toxic eczema or allergic contact dermatitis.
When epoxy fumes are inhaled they can affect the nose, throat and lungs, causing irritation, and being exposed to epoxy resin repetitively can result in sensitisation and asthma.
According to Health and Safety Executive, 12,000 lung disease deaths each year are estimated to be linked to harmful chemical exposures at work, so it is imperative to wear personal protective equipment (PPE) such as gloves, glasses and especially respiratory masks to reduce your chances of injury or illness in the workplace.
At Anchor Fixings, we stock a variety of chemical resins from the Buffalo resin range. Buffalo resins have been specifically been designed to provide for all applications and sectors of construction and benefit from a clear colour coded selection criteria, which makes it easy to select the resin that is best for your application.
They are supported by the many approvals required by the construction industry to meet international standards, giving you 100% peace of mind in product performance and regulatory compliance.
We’re often asked our advice on what type of resin is required, the quantity of resin required and whether certification is available. We can specify which resin to use and if a particular brand has been specified we will advise on the more cost effective solution. We can supply certification as required.
We can also provide an estimation of quantity required for each individual project using our Resin Calculator.
Get in touch with our fast and friendly team for more information and pricing, or place an order through our enquiry basket. We can deliver it straight to your site if you’re too busy to collect, plus any orders over £100 will even receive free sweets on us!
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This article was written by Anchor Fixings Director Andy Walker.
Using experience and knowledge gained over the last number of years and working closely with Resin manufacturers, we are in a well established position to offer advice on which resin is suitable for your application.