The History of Adhesives; Why The Future of Adhesives is going back to its Roots

Adhesives have been used for ages. Literally, ages. Today, you may recognise the adhesives used for DIY use such as super glue. Or the glue used to bond your phone together. Or even the glue used to bond parts of your car.

Or, maybe you didn't know of these items before. 

I can almost guarantee you didn't know that the use of glue stretched all the way back to the Egyptians. There are also examples of glue used for ancient tools and hunting weapons.

Adhesives have a fascinating history. You just don't know it yet.

Here at Forgeway, we manufacture adhesives. Our products range from structural adhesives to sealants. And with over 25 years of experience manufacturing these products, we wanted to take a look back through history to see where it all started. 

In this article, we analyse the early use of adhesives. We also analyse how they rapidly evolved during the world wars. Finally, we will look to the future of bonding and pose the question, does the future of adhesives need to look back to its roots?

Introduction to adhesives and bonding

In case you didn't know, an adhesive is any non-metallic substance used to bind two or more items together. It is used to prevent the items from separating.

There are, of course, many different types of adhesives. These days, the vast majority of the adhesives we use are formulated with synthetic polymers.

However, you can also find natural-based formulations made from tree resins, animal parts (yes horse bones), and bitumen.

Despite the different variations, all adhesives have the same goal. Bond items together. That's what they have been doing throughout history. We anticipate they will continue to do so as we head into the future.

The use of Adhesives throughout History

There are countless studies on the history of adhesives. They go into great detail about how adhesives have been used through each of the ages.

We aren't going to go into the same level of detail.

Instead, we are going to highlight some of the more fascinating use cases over millennia.

Scientists have apparently dated some of the earliest glues to more than 200,000 years ago. These glues were made from a birch pitch and were used to create weapons and tools.

Years of continued adhesive use followed for various purposes like statues, pottery repair, and decorating human skulls. Lovely.

By the time we arrive at the Egyptians, there was a wider range of glues available. Animal by-products like bones, hair, and even blood as well as various vegetables and plants were being used to create glue-like materials.

The Egyptians used adhesives to help create some of Tutankhamun's treasures as well as his tomb. A few millennia down the road, the Romans used glue to bond together shields, weapons, and military equipment.

The Greeks from a similar period were also very familiar with glue. In fact, the Greek word Kolla means glue. Its origin derives from the word Kollops which is the thick skin around the necks of cattle used to make glue.

As a result, several languages around Europe use this as their root word. (Colla in Italian and Colle in French both mean glue). English words like collagen and protocol also derive from the original Greek word.

Most scholars and academics widely document that the use of adhesives and bonding declined after the fall of the Roman empire. The same documents suggest that widespread adhesive use didn't pick up again until the 17th century.

However, several sources indicate this assumption isn't entirely accurate. Several artists heavily used adhesives in their work between these periods.

There was also the small matter of the Mongol Empire. Genghis Khan's fearsome army heavily used glue in their bow and arrow construction. Even Shakespeare made a few references to 'glue' in his plays.

But, it wasn't until the 17th and 18th centuries that widespread adhesive use became documented. World-famous furniture manufacturers used glue in their designs.

There was also an interesting development a few decades earlier. In 1632, the Court of Aldermen settled a centuries-long dispute. One of the biggest points of contention was the use of glue in furniture making.

As a result, only The Joiners were allowed to use glue in bed-stead construction. The Carpenters had to settle and 'only' use nails.

You might be surprised to learn that the debate between glue and nails (or any mechanical fixings) still rages today.

From the 18th to 19th and even early 20th century, adhesives were almost entirely made from the same natural ingredients used for thousands of years.

Although the development of these natural-based adhesives had improved dramatically, it was the breakthrough of Synthetic Polymer-based adhesives around 1925 that changed the landscape of adhesives and bonding forever.

Why World War 2 helped Trigger the Industrialisation of Adhesives

As we alluded to in the previous section, around 1925 marked a significant shift in adhesive base chemistry. Before that, aircraft and some automobile manufacturers used various natural products such as casein glue and collagen glue which is made from milk and animal bones.

Believe it or not, if passengers could smell a distinct smell like off-milk, it was an indication the adhesive was close to failure. That was if it hadn't already failed.

It's also why the stereotype about 'Horses being sent to the glue factory' exists. This sign from around World War One is a perfect example.

Leading up to World War Two, there were two main synthetic-polymer-based adhesives. Firstly Phenol-formaldehyde up until 1930. After which Urea-formaldehyde became more popular.

Norman De Bruyne helped pioneer the use of these Urea-formaldehyde (UF) glues. In 1937, the RAF approved one of his adhesives called Aerolite. Today, this adhesive is still a standard wood-working adhesive.

When war broke out in 1939, the next few years would see many breakthroughs for bonding. Here, we highlight the three most significant discoveries.

Glue helped the Mosquito Plane Project get off the ground

As war raged and technology advanced, the need for a lighter, faster, and more manoeuvrable fighter plane increased. Enter the De Havilland Mosquito. It was influential in helping Britain dominate the skies.

Its unprecedented wood-based design was impossible without Urea-formaldehyde adhesives. Norman De Bruyne helped De Havilland develop the Mosquito into a lethal weapon.

President Roosevelt approved the use of the first Duct Tape

There were already tapes in existence during the war. Applications across the frontline used Scotch-branded tapes. In 1943, President Roosevelt approved the use of an innovative tape that was very strong and could be easily torn to the correct size.

This tape was extremely useful. It helped the military instantly repair equipment, weapons, and vehicles. 

After the war, this tape would go on to be very popular in the construction industry for repairing ducts. The product 'Duct Tape' was born. It's now the Duct Tape we all know and love. All thanks to President Roosevelt; kind of.

A Scientist accidentally discovered Super Glue

Everyone knows super glue. The small tube of glue you still have lying around in a random cupboard which has probably cured up and can’t be used anymore? Guilty...

Well, the discovery of this iconic glue was entirely an accident.

In 1942, a gentleman named Dr Harry Coover was researching a new compound called cyanoacrylates. He envisaged it could be used for creating crystal clear gun sights.

This compound was crystal clear, incredibly durable, and cheap to formulate. However, it was far too sticky to work with so they didn’t take this discovery any further. 

Over 10 years later, Coover picked up the project where he left off and created a super sticky glue that could cure in 9-10 seconds. He then packaged the glue into small containers and put them on the shelf in stores as Eastman 910, “The Superglue”.

It’s the exact same base chemistry that you still use today to fix lampshades and chair legs (or whatever you use super glue for).

Why the Aerospace Industry Pioneered the Use of Adhesives

There are many factors behind the exponential increase in adhesive use.

The De Havilland Mosquito was one of the first aircraft to significantly use adhesives. Norman De Bruyne, who pushed the RAF to approve the Aerolite adhesive in 1937, was instrumental in this Mosquito project.

In 1942, he developed a product called Redux (stands for Research at Duxford). This adhesive could reach strengths of up to 15MPa which we would qualify as a structural adhesive.

A few months later, The Ministry approved Redux for use in aircraft construction. But before the RAF could use them, the army used this product to bond clutch plates in tanks and increased the lifespan tenfold.

It wasn't until the end of the war that the first structurally bonded aircraft parts took to the skies; The De Havilland Hornet.

Following the war, De Havilland and De Bruyne continued to be the pioneers of bonding and adhesives. Several De Havilland planes pushed the use of structural adhesives to the limits.

Even the infamous De Havilland Comet, revolutionary at launch, was designed with an extensively bonded structure. However, due to cost-saving efforts, they used rivets instead.

This replacement was one of the main reasons why the Comet catastrophically failed.

It was around this time (the 1950s) that epoxy adhesives started to take a stronghold in the adhesive industry. Due to the bad publicity associated with the Comet, the Redux brand took a hit and epoxy adhesives took their place.

Epoxy adhesives could boast very high strengths. The main downside was the brittle nature which could cause the adhesive to crack when exposed to impact or vibrations.

In the 1970's, the most important breakthrough came when rubber modifiers were added to the base chemistry. This drastically improved impact and fatigue resistance.

This led to the Boeing 727. It was almost entirely bonded with epoxy adhesives. To this day, many modern aircraft are using adhesives to use composite materials instead of metal to reduce weight and increase efficiency.

Other industries were much slower on the uptake. Automotive manufacturers used adhesives sparingly for minor parts of their design. The sports industry was slightly more proactive such as skis switching to a bonded design.

But in general, it is the Aerospace industry has made the most of using adhesives and bonding in their design. They are largely responsible for the majority of the major advancements with adhesives.

What does the future hold for adhesives?

All of these breakthroughs. All of the brave decisions. All of the hard work. It's led us to today. The world as we know it wouldn't be possible without adhesives.

And we would argue the future is also heavily reliant on adhesives. But what does that future look like? What are the adhesives of tomorrow?

Ironically, the adhesives of tomorrow are tantalisingly similar to the adhesives of yesterday. The same adhesives that helped build the key components of early civilisations are looking like the adhesives that will help build future civilisations.

As we all become more aware of our environmental impact, the manufacturing world is increasingly looking at 'green adhesive solutions'. Adhesives that use natural and renewable ingredients for their base formulations.

There's a hint of poetic justice. After centuries and millennia of using natural ingredients to create adhesives, it has taken just 100 years to realise that synthetic adhesives aren't the answer. 

Whilst synthetic ingredients have taken adhesives and bonding to new heights (literally), it's the same natural ingredients used by our ancestors that will bond the foundations of our future.