You’re rushing out the door for work when you realize you forgot to pack your children’s lunches. Frantically, you scribble ‘PLEASE FEED KIDS’ on a sticky note and slap it onto the fridge for your unsuspecting partner to find.
Using a sticky note is a simple example of creating an adhesive bond, but what exactly are adhesive bonds, and how are they used in modern applications?
Strouse processes adhesive tapes on our machines daily and constantly tries new combinations of adhesives and liners to achieve maximum effectiveness on all our custom parts.
We’ll review the definition of adhesive bonding and a list of examples to help you understand how the process works and how you can select effective adhesive materials for your projects.
What is Adhesive Bonding?
Adhesive bonding is the process of joining multiple objects or surfaces using an adhesive material.
Think back to our initial example of a sticky note:
When your fingers press the adhesive side of the sticky note against the refrigerator, its low surface energy creates loose bonds between molecules, allowing them to seep into the solid yet microscopically textured surface of the fridge and form adhesive bonds.
Rubbing the edge of the sticky note allows it to stick more effectively. Applying force to an adhesive bond presses the molecules deeper into the surface, A.K.A., the substrate, and allows its molecules to interlock with your adhesive.
The molecules of your adhesive are similar, which allows them to stick to themselves (cohesion), but introducing a new surface causes the different molecules to attract toward one another (adhesion). The strength of the adhesive depends on its unique viscosity, or ability to flow or spread, and its surface energy.
ADHESIVE BONDING SOLUTIONS
Adhesive bonding solutions can join the internal or external components of a product.
When it comes to building a product, your intended location, function, and geometry will help determine which adhesive bonding solution is ideal for your part’s intended design and purpose.
Possible adhesive bonding solutions include glue, epoxy, and Pressure Sensitive Adhesive (PSA), which can all form bonds between different surfaces. The final choice between them depends on which traits you prioritize.
MECHANICAL FASTENERS AS AN ALTERNATIVE
As you already know, adhesive bonding isn’t the only way to combine two surfaces: mechanical fasteners (bolts, screws, rivets, and more) often serve the same function of holding parts together as an adhesive bond.
Mechanical fasteners are often applicable during heavy-duty applications where there’s a need for future maintenance or the potential threat of experiencing sudden movement.
However, fasteners weigh more than other bonding solutions, and often rely on puncturing a material's surface, making them an aesthetically unappealing choice.
5 Examples of Adhesive Bonding
It’s challenging to understand the type of high-strength bonds we’re discussing when you’re used to using adhesives like painter’s tape.
The following list explains a few bonding examples we’ve collaborated on to help you understand how adhesive bonds function, ranging from higher- to lower-strength adhesion, depending on the part application.
1. FIXING AUTOMOTIVE TRIM TO A PAINTED SURFACE
Automotive trim is thin, lightweight, and designed to fit onto and into the seams of cars to differentiate between models. Your trim requires considerable adhesive strength to withstand the daily tribulations of weather and the road.
The car trim, typically plastic-based, can be laminated with an adhesive on one side to help it stick to the painted surface of your bumper, side panels, or car doors.
Creating an adhesive bond eliminates the possibility of dirt or contaminants between the surface and the trim while also making a more aesthetically pleasing look.
2. BONDING SOLAR PANELS TO A FRAME
Solar panels must withstand tumultuous winds and other turbulent weather conditions that pose a risk to their functionality.
In a solar panel system, wind can make its way between the roof and the panels themselves, causing them to lift up and detach from the racking system. Establishing powerful adhesive bonding connections between the solar array structure and the panels themselves helps reduce the chance of critical damage during heavy weather conditions.
3. SEALING ELECTRICAL BOXES
Although users can seal electrical boxes using various methods, such as mechanical fasteners, you still want to keep as much moisture out of an electrical box as possible.
The internal attachments of an electrical box are vulnerable to water damage, and fasteners such as screws leave tiny gaps and corrode over time, risking leakage.
Fixing electrical box covers in place using high-strength tapes not only holds the box itself together but also seals out dirt and moisture. A strong adhesive bond between panels will create a tight seal to protect the breaker wiring and other electrical components.
4. VIBRATION AND SOUND DAMPENING PARTS
Vibration and sound dampening tools are applicable to multiple industries, including manufacturing, aerospace, and automotive. There are two main methods of establishing adhesive bonds for vibration and sound prevention:
- The first strategy is to use foam and other materials with shock- and sound-absorption capabilities to create vibration and sound dampening gaskets or other pieces
- Another method you can use is putting down larger pads to absorb vibration and sound using attachment methods like tape along the edges to ensure the absorption material makes contact with the surface of the wall or floor
In the past, Strouse collaborated with Toyota to find better ways to connect bulky foam pieces within the interior of the vehicle's doors. These pads cushioned other parts to prevent them from rattling around and making excessive sound.
5. STICKING A MONITOR TO A PATIENT’S SKIN
Medical monitors, such as glucose monitors, often attach directly to a patient’s skin, which requires an adhesive that can establish a firm bond without discomfort.
Forming an adhesive bond against the skin can pose other unique challenges. For instance, some monitors have additional attachments, making them heavier, while others are smaller, lightweight, and relatively easy to manage.
Whether intended for cosmetic or medical purposes, stick to skin adhesives must be chosen with the proper care and go through any needed validation and verification before being produced by a manufacturer.
Is Adhesive Bonding Right for My Product?
Adhesive bonding is a single process that encompasses multiple solutions.
You might be looking for a highly-rigid, relatively inexpensive solution, in which case mechanical fasteners could be right for you. However, if glue, epoxy, or pressure sensitive adhesives can bond the objects or surfaces you need, they’re worth considering for your custom product.
When you hear adhesive, are you picturing rolls of tape? Instead, you might want to learn how adhesive material gets cut into durable, long-lasting parts for a wide variety of applications.
Rather than using adhesive tape rolls, modern manufacturers often collaborate with flexible material converters like Strouse to transform rolls of tape into die cut adhesives.
If you’re designing a custom product, you’ll want to consider adhesives with the right shape and material to match the substrates with which you intend to create adhesive bonds.
Learn more about die cutting and take the first step towards proofing your product for its intended application.