The history of industrial adhesives
Before we look at the adhesives available today, it’s useful to consider the origins of glue and how it has changed over time.
Signs of adhesive use date back thousands of years with organic glues – typically either tar-based (made from the bark of a birch tree, for example), or from the prolonged boiling of animal hides, hooves, and connective tissue – often found in pottery, utensils, weaponry, and before this, even in cave paintings.
It’s in the time of the Greeks and Romans, however, that adhesives became more advanced with animal glues being mixed with other substances to increase strength and performance; leading to glues being used in countless ways, including in construction, with adhesives used to set glass, and wall and ceiling tiles. Even in Greek mythology there is evidence of adhesive use, with Icarus using wax to attach his feathered wings before the inevitable melting when flying too close to the sun!
The Romans were also the first to use sealants – produced from beeswax – on their boats and ships.
Fast forward to the 1920s and the introduction of the first plastic polymer and synthetic adhesives were born; twenty years later, with the start of the Second World War, adhesives played an integral role in manufacturing wartime equipment, which in turn spurred the development of more sophisticated adhesives with the focus on improved flexibility, strength, cure time and temperature and chemical resistance.
In the last hundred years, new polymers and formulation technologies have expanded the number of synthetic adhesives available.
What is an industrial adhesive?
Although both organic and synthetic adhesives are available today, synthetic glues are the most widely used in industry – that said, concerns about the environment are helping to refocus the market on more sustainable bonding solutions that include renewable, natural materials.
Organic adhesives can be made from animal resources such as beeswax; vegetable starch from corn, potatoes, sugarcane, and wheat; as well as natural resins such as casein, a milk-based protein.
Whilst they have been replaced by synthetic products in many industries, they are still widely used in some applications – for example, starch-based adhesives are used for tube winding, bottle labelling, paper bags, and corrugated boxes and board.
Meanwhile, synthetic adhesives are derived from human-made polymers, and whilst they typically cost more, they offer stronger and more durable bonding with greater options for customisation.
Another way to define industrial adhesives is to categorise them by the type of cure – usually by reactive and non-reactive adhesives.
Reactive adhesives require a chemical reaction for an adhesive bond, and are often used for high-load, structural applications that include the bonding of metals, concrete, glass, plastics, and wood.
Examples include multi-part options – often combing a resin and a hardener/curing agent – that are mixed to create a bond, and single-part adhesives that require an external energy source such as UV light, heat, or moisture to form a bond.
Non-reactive adhesives include hot-melts, pressure sensitive adhesives, drying adhesives (solvent-based and dispersion adhesives), and contact adhesives; these glues do not need a chemical change to form a bond.
Hot-melt adhesives are thermoplastic-containing polymers that are applied in a molten state, which then solidify upon cooling, forming a bond. Widely used in the packaging industry – in applications as diverse as case and carton sealing, aseptic packaging, and coffee cup construction, as well as many other industries, hot melts are easy to apply and incredibly versatile.
Pressure sensitive adhesives work with the application of light pressure and can be designed to provide a temporary bond (decorating tapes, e-commerce tapes, skin contact patches, and dressings), or a permanent bond (safety labels, automotive interior trim and vibration, and insect traps).
Benefits of industrial adhesives for your business
In contrast to other fastening techniques, adhesives can bond a wide range of materials, limit the chances of bond failure by distributing stress across a joint more efficiently, as well as improve the aesthetic qualities of a product’s design.
Adhesives can also be formulated to meet the needs of an application; tailoring the viscosity and bond strength – amongst other performance qualities - to ensure the end product meets the needs of producers and customers alike.
Furthermore, manufacturing efficiency is enhanced by the ease with which adhesive applications can be automated as part of a production process; helping to reduce waste, lower costs, and boost production uptime.
How to choose the right industrial adhesive
Change of substrates, new production applications, poor performance, or moves towards greater sustainability; there can be many reasons why a business would want to switch adhesive and/or adhesive supplier.
To do this, a series of questions need to be answered to ensure the right adhesive is chosen:
- What is the application?
For example, is this a packaging product that runs on a fast production line.
- What substrates need to be bonded?
Does it include, for example, a high percentage of recycled material that may be difficult to bond.
- In what environment will the glue be used?
Is it a cold and wet setting such as a brewery, or a warm and humid environment as found in many tropical climates.
- Is the adhesive compatible with the stress it will be under?
Does it have the necessary adhesion.
- What open time and setting speed is required?
Is it a slow or fast production process.
- Is a particular product standard necessary?
For example, a food safety standard or vegan safe certificate.
This list is not exhaustive, just an example of some of the considerations when choosing a new adhesive.
Taking advantage of an industrial adhesive supplier’s expertise and knowledge is also incredibly important. Businesses should ask about their pre-and after-sales service – do they offer adhesive switchover support, for example – and are they able to customise adhesives, so the glue is to tailored to the specific application?
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For more information about industrial adhesives from Beardow Adams, and how they can support your business improve bonding efficiency and performance, contact us by sending an email to: marketing@beardowadams.com or visit the contact us page.