What Are the Different Types of Adhesives?

You know that stick of glue from kindergarten? That's an adhesive! How about that gum you used to plug a hole in your leaky pipe? It's gross, but that's also an adhesive. Turns out, we use these bonding substances more often than we might realize. They're a huge part of many things we rely on every day, from our cars to the roof over our heads!

Which types of adhesives are out there? How are they used? Stick here and get ready to form a bond with this useful material!

Our everyday life is inconceivable without self-adhering (tacky) materials or adhesives.

– Mikhail M. Feldstein, author of Innovations in Pressure-Sensitive Adhesive Products

What Are Adhesives?

At their most simple, adhesives are substances used for sticking objects or materials together. In scientific terms, those substances that are sticking together, regardless of what they are, become known as "substrates."

Think of a peanut butter and jelly sandwich. You could say the peanut butter and jelly is an adhesive for the two pieces of bread, the substrates.

Many adhesives are made for specific purposes, depending on the industry and the substrates that need to be bonded together. For instance, there might be a special glass adhesive for a car window, but a completely different one for a coffee table. Each has its own unique formula and is specifically designed for a particular need.

What's in an Adhesive?

Adhesives are most often made from polymers or resins, which are chemical structures that can eventually be recognized as plastics. However, that's not all that can be found in adhesives. They can also contain:

Animal Product
Acrylate
Acrylic
Copper
Epoxy
Grains
Graphite

Milk
Nickel
Nylon
Plants
Polyester
Acrylic
Oil

Polyurethane
Rubber/Latex
Silicone
Silver
Starch
Vegetables
Water

Think about going to the craft aisle and seeing all the different glues. No one is the same as the other, which is why you might use tacky glue for repairing a broken trophy but a glue stick for your kid's art project. The substances above work in the same way. One could be good for adhesives used in construction, while the other works better for stamps and envelopes. It just depends on the manufacturer and their need.

How Are Adhesives Classified?

Adhesives are often broken into two types, depending on how they're made. They are classified as either pressure sensitive or polymer-based, though there are also other classifications that include:

1. Anaerobic
2. Bismaleimides
3. Casein
4. Cyanoacrylate
5. Dextrin
6. Electrically conductive
7. Hot melt
8. Phenolic

9. Plastisol
10. Polyvinyl Acetate (PVA's)
11. Reactive
12. Solvent-Based
13. Thermoset
14. UV Curing
15. Water-Based

What Are Pressure Sensitive Adhesives?

Pressure sensitive adhesives consist of acrylics, rubber/latex, or silicone. They don't need a solvent, water, or heat to stick and can be applied with light pressure to paper, glass, wood, plastic, or metal.

Used for:

What Are Polymer-Based Adhesives?

Polymer adhesives are broken up into polyester, polyurethane, acrylate, and epoxies. Polymer-based adhesives are considered the best for bonding woods, but are actually used in many other industries.

Used for:

Ultimately, adhesives are classified based on whether they use a solvent, water, heat, or any combination of the three to stick to a surface. Here are the other ways they can be classified:

Anaerobic

You won't find any solvents used in anaerobic adhesives. They work best bonding metal together, typically in large machinery and other heavy duty equipment.

Bismaleimide

Bismaleimides are also referred to as BMI adhesives. They are used in electronic circuit boards, but also join metals, glass, ceramics, and some plastics.

Casein

This type of adhesive is made from milk protein. It's extremely strong, resistant to water, and has been used since ancient times to make musical instruments, bottles, furniture, and even aircraft!

Cyanoacrylate

Have you ever fixed something with Super Glue? Well, then you've used a cyanoacrylate adhesive! Cyanoacrylates react with moisture and work best for super gluing plastic or rubber objects.

Dextrin

If you've ever read a good book, then you've interacted with dextrin adhesives. This thin glue is made with starch and is used to hold the pages together in your favorite novel.

Electrically Conductive

If you need to repair your electronics, you'll likely use electrically conductive adhesives. This type of adhesive is known for being extremely durable and long-lasting.

Hot Melt

Hot melt adhesives are heated to melt and then cooled to solidify and bond materials. They're also referred to as polyamides and work best for woodworking projects, packaging, and trade show exhibits.

Phenolic

Not only do phenolic adhesives bond metal with metal, but they also bond metal to wood. Since it withstands tough conditions, this is a good adhesive to use for a variety of projects. For instance, you may find it in the front door of your home or business.

Plastisol

These are modified versions of PVA's and require heat to harden. This adhesive is commonly used as a textile ink for screen printing and coating outdoor applications like roofs and furniture.

PVA's (Polyvinyl Acetate)

Your standard white glue is referred to as polyvinyl acetate or PVA. It's good for craft projects, but can also be used for projects that require more industrial strength.

Reactive

Be thankful for reactive adhesives. They are used to bond cell phones, computers, and even some medical devices.

Solvent-Based

If you remember anything about chemistry class, you might recall that a solvent is a liquid in which other materials dissolve to form a solution. This kind of adhesive is mixed with polymers and can be found in sticky notes.

Thermoset

Despite their name, thermoset adhesives may or may not need heat to cure. This adhesive is often used in construction since it's super strong and long-lasting.

UV Curing

It was the early 1960s when these adhesives were first on the market. Since then, they have grown rapidly and are now essential in the electronic, automotive, and medical fields.

Water-Based

Water-based adhesives have a similar texture to cement and are often used for decorative concrete. They can also be found in product packaging, bottling, and furniture building.

Keep in mind, the categories above are not all mutually exclusive. That means you can have an adhesive that's both UV curing and reactive or a plastisol that's also solvent-based. It all depends on how the adhesive is made.

Would you rather watch than read? Check out this video!

The Pros & Cons of Each Type of Adhesive

Now that you understand a little more about adhesives, let's dive into the different advantages and disadvantages of each. Your substrate is a key factor when it comes to the right adhesive for the job. However, there are still a few other general points to keep in mind.

Type

Pros

Cons

Anaerobic
Pros:
• Cures as quickly as 10 minutes
• Works best with metal objects
• No need for washers or gaskets
• Long shelf life
• Enhanced quality of finished product
• Removes corrosion
• Cost-effective
• Contain no solvents
Cons:
• Will not set with excessive liquid
• Speeding up the curing process decreases strength
Bismaleimide
Pros:
• Resistant to high temperatures
• Suitable for long-term exposure
• Paste is easy to mold
Cons:
• Takes several hours to cure
• Rigid design
• Doesn't create a strong bond
Casein
Pros:
• Moisture-resistant
• Long shelf life
Cons:
• Takes several hours to cure
• Rigid design
• Doesn't create a strong bond
Cyanoacrylate
Pros:
• Solidifies within seconds
• Versatile; bonds metals, plastics, rubbers, and glass
• Withstands high amounts of pressure
• Easy to handle
Cons:
• Less resistant to moisture
• Low heat resistance
• Rigid design
• May not fill spaces as well as other adhesives
• Short shelf life
• High cost
Dextrin
Pros:
• Heat and cold resistant
• Made quickly
Cons:
• Thin, frail finish
• Breaks down when exposed to water
Electrically Conductive
Pros:
• Contains no solvents
• Lead-free
• Cures rapidly at moderate temperatures
• Results in limited waste
• Free from air bubbles
• Durable
• Long shelf life
Cons:
• Breaks down when exposed to extreme temperatures
• May be slightly more expensive
Hot Melt
Pros:
• Versatile
• Affordable
• Moisture-resistant
• Strong
• Flexible
• Long shelf life
• Doesn't have to cure
• No loss of thickness when solidifying
Cons:
• Can only be applied with a hot enough temperature
• Difficult to handle
• Cures faster when the substrates are preheated
• Takes 24 hours to cure
Phenolic
Pros:
• Good for bonding metals together or metals with wood
• Maintains structural integrity and stability in severe conditions
Cons:
• Requires heat and pressure
• More expensive
Plastisol
Pros:
• Resilient and tough
• Easy to handle
• Fast production
• Easy waste disposable
Cons:
• Requires heat to harden
• Doesn't ever fully dry
Polymer
Pros:
• Dries clear
• Strong, permanent bond
• Versatile; used for glass, plastic, and wood
• Applied via brush, powder, or spray
Cons:
• Slightly difficult to handle
• Too much solvent will weaken the adhesive
• Cure time is at least 10 hours
Polyvinyl Acetate (PVA's)
Pros:
• Versatile and flexible
• Inexpensive
• Doesn't yellow over time
• No fumes
• Dries clear
Cons:
• Works best in an air-conditioned room
• Shorter shelf life
• Breaks down with water
Pressure Sensitive
Pros:
• Thin and light
• Bonds with substrates made from a variety of materials
• Super sticky
• Works with a variety of temperatures
• Safe and easy to install
• Provides sound and vibration control
Cons:
• Not sustainable with heavier objects
• Can be expensive, depending on the type
• May require special equipment for application
Reactive
Pros:
• Resistant to chemicals, heat, and moisture
• High bond strength
• Long-term durability
• Withstands severe environmental conditions
• Fast curing
Cons:
• Must be applied accurately and in proper volumes to be most effective
• Begins curing as soon as it's exposed
• May require dispensers or machinery for use
Solvent-Based
Pros:
• Applied via brush, roll, or spray
• Evaporates quickly
• Bonds immediately with the substrates
Cons:
• More expensive
• Flammable
• Releases emissions in the air during production
Thermoset
Pros:
• Super strong
• Used for heavier applications
• Long-term stability
Cons:
• Fairly expensive
• May need heavy machinery for application
• Cannot be melted again or reshaped
UV Curing
Pros:
• Low process temperatures
• Rapidly advancing as an adhesive
Cons:
• Requires UV light in order to function
• Expensive for smaller productions
Water-Based
Pros:
• Less expensive
• Flexible
• Sets quickly
• Strong
• Applied by either spray or roll
Cons:
• Breaks down when exposed to excess water or moisture
• Sometimes has a strong odor
• May irritate the user's skin

As you can see, no adhesive is designed the same way. Each one has a unique chemical makeup and different properties. The right one for the job can be determined by considering budget, turnaround time, and the substrates that need to be bonded together.

Which Industries Use Adhesives?

Almost every industry can use adhesives in some capacity. However, there are a few that couldn't function or exist without them. This material has contributed to many essentials we use almost every day.

Arts & Crafts
Automotive
Construction
Dental

Food
Interior Design
Medical
Promotional Products

Art & Crafts

Creative genius would be impossible without adhesives! How else can you build a diorama of the solar system for your kid's science fair?

Automotive

Many car parts are held together thanks to adhesives. You can find them everywhere from body work to the sweet emblem on a fancy BMW.

Construction

Landmarks like the Eiffel Tower or Golden Gate Bridge wouldn't exist without adhesives. Aside from bolts, screws, gussets, and other finishes, this is what helps each piece stick together.

Dental

While it may seem strange, some adhesives can be found in your mouth. They are often used for braces or dental restoration procedures.

Food

Bags of potato chips, bottled drinks, and many other delicious snacks are sealed with adhesives. If the bag is hard to open, that just means the adhesive is really doing its job!

Interior Design

You will find adhesives in some furniture and wallpapers. Ultimately, these decorative touches are what help create that "home sweet home" feeling.

Medical

Bandages, gauze, and other medical essentials are designed with adhesives. That's why it hurts so much when you have to peel off a Band-Aid®.

Promotional Products

Popular advertising giveaways like PopSockets™ and cell phone wallets rely on adhesives to work. These logoed gifts tend to stick in people's minds.

An Adhesive for Every Occasion

Of course, you don't need to be a business or work in an industrial setting to benefit from adhesives. There are many on the market that are sold over-the-counter at Home Depot or Menards and can be used in basic home repairs and other household projects. It just depends on what you're looking for and how much you have to spend!

The Bottom Line

Adhesives have a long history of use in a variety of industries. Every one is designed a bit differently and has a particular place where it can be used to its full potential. Take the time to really understand the difference before starting your next project!

Alyssa Mertes

amertes@qualitylogoproducts.com

866-312-5646 x 277

Alyssa is the Lead Copywriter at Quality Logo Products. As a promo expert, she's uncovered the world's first custom tote bag, interviewed the guy behind rock band ACDC's logo, and had a piece published by the Advertising Specialty Institute, a leader in the promotional products industry.

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