Glue. That useful adhesive that got you through countless art projects in school and fixed many broken items without your parents ever finding out (They probably know by the way!)
When you think of glue, you probably don’t immediately think that it’s flammable. Glue and flames. That’s a strange combination that isn’t seen that often. However, on certain occasions, glue substances and high heat sources may meet.
Maybe you’re doing a DIY project and need to use a torch near some adhesive. If so, you will need to know if the glue is flammable or not and whether it is safe to mix the two.
We all work with glue at some point so it is important to know how safe you are around it. When using water-based glues, these are not generally flammable.
However, they can still burn if exposed to direct flames or high temperatures. Other adhesives such as superglues (Cyanoacrylate), rubber cement, model glues, and spray glues are somewhat more flammable.
You must understand what kind of glue you are working with and how dangerous it could be if it became exposed to a naked flame or high heat. Today, we are going to discuss how flammable different types of glue can be so you can continue your projects in complete safety.
What are the different types of glue?
There are a wide range of different glue types available. Each of these have unique properties that see them behave under certain conditions in different ways.
While many of these glues are not used by the average person on a day-to-day basis, some are actually pretty common in office or home environments.
Some of these glues are:
- Fabric adhesives such as PVA (Poly Vinyl Acetate) - This glue is typically used to bond fabrics together.
- Epoxy - This is a two-part resin. When two objects are combined, this glue forms a significantly strong bond.
- Hot glue - Here is a glue that is made from polymers. These must be melted to work properly.
- Glue sticks - Often used by children, glue sticks don’t form hard bonds and are completely non-toxic.
- PSA (Pressure Sensitive Adhesive) - This glue is a set of compounds that cure when under a certain amount of pressure.
- Polyurethane - A glue that is polymer-based and requires tight clamping to cure effectively.
- Super glue - Also known as cyanoacrylate adhesive in industrial circles, these glues are non-water-based and set extremely quickly, forming an ultra-strong bond.
- Spray adhesives - Simple contact adhesives, this glue is sprayed onto surfaces before bonding.
- Wood glue (yellow) - Here is another water-based adhesive. It sets very quickly with up to three different types that all have distinct properties.
- White craft glue - Practically non-toxic, this is a water-based glue that is easy to clean up and regularly used by children.
When we consider different glues, we can see that not all have the same flammable properties as the next. Take epoxy resin, for example. This is not very flammable once it has cured. However, prior to mixing and curing, the chemical agents within this resin can be quite flammable.
That being said, here are some of the most common glues you will work with and whether they are flammable or not:
Flammable or not?
Gorilla glue is a type of super glue. And as a liquid, it is very combustible. Therefore, you should never smoke cigarettes when you’re using or near Gorilla Glue. Ideally, it should only be used outdoors or in a well-ventilated space.
This will prevent any combustible fumes from building up as you work with the glue.
As with many types of glues, Gorilla Glue is not flammable when it is dry or cured. This is because the flammable components within glues have usually evaporated once it has dried so it is no longer flammable.
However, just because it isn’t deemed flammable doesn’t mean it will not burn.
There are a few versions of Elmer’s glue. When considering the white form that is often used in schools, then this is not flammable.
On the other hand, clear Elmer’s glue can be flammable but only once it has dried out. Because it is water-based, it is not considered flammable when in its liquid form so it will not burn under normal circumstances.
This frequently used adhesive is not flammable. PVA glue emits zero fumes meaning it is also non-toxic and safe to use. Nonetheless, PVA glue can still burn. Under the right amount of high heat, it can become flammable.
All forms of super glues are flammable when in their liquid states. They also emit fumes that can be flammable too. Under the right conditions, just a small drop of super glue can ignite other materials such as cotton.
This is because of the curing process. As the glue dries, an exothermic reaction occurs meaning that heat is created. More heat equals a higher chance of ignition.
Wood glue is regularly used in DIY projects and is relatively non-flammable. It also emits very little fumes which means it is pretty safe to use indoors and in enclosed spaces.
However, as with most materials, wood glue can burn. Certain toxic materials have been found in wood glues over recent years which can be dangerous when set alight. If you need to burn wood glue, make sure that it is done away from others so the toxic smoke isn’t breathed in by anyone.
You’ll be pleased and relieved to know that most school glues, as well as glue sticks, are not flammable. Instead, they are better at extinguishing flames due to their water base.
Nonetheless, you should read the labeling on the side of all glues to ensure they are safe to use around high temperatures and flames.
Keep children far away from sources of flames because other elements can also be combustible as well as glue.
This solvent is flammable and toxic but only before it dries. Once it is dry, nail glue is safe. However, various nail glues can emit harsh fumes although most of these are usually latex-based.
Other than that, nail glue contains different chemicals that can cause a thermal burn on your skin once they react with cotton.
Does glue catch on fire?
If any materials become hot enough, they can eventually catch on fire. However, this doesn’t technically mean it is flammable. As you can see above, different types of glues have unique properties which can make them flammable or non-flammable.
Glue is more complicated when we ask if it can catch on fire because of the many types of glues and the chemical properties within them. Also, these chemicals alter before and after curing (drying).
While some glues are flammable when in their liquid state, others are flammable when dry. However, the latter is less common.
So, glue can catch on fire depending on the environment and temperatures but, as with most materials, it depends on the chemical properties that make up the substance.
What types of glues are not flammable?
In general, any water-based glues are not flammable as well as certain plastic glues such as PVA. Although these glues are considered non-flammable, we highly recommend reading the packaging of different adhesives before use.
This is the best and safest way to find out if they can be used safely. Remember, some glues emit toxic fumes so you must take all safety precautions beforehand so you and others around you do not become unwell.
While most everyday glues are not flammable, many forms of adhesives can emit toxic fumes once they are heated. However, some types of glues are highly flammable but it depends on whether they have cured or not and the properties they possess.
Always take precautions and assume that the glue you are using is flammable. That way, you and others will always be safer around different adhesives.