What Are Structural Adhesives?
Structural adhesives are high-strength bonding materials that exhibit exceptional load-bearing capabilities when fully cured. 3MTM structural adhesives come in many varieties, which are organized by chemistry family. Each family offers unique performance characteristics, including durability, flexibility, fast bonding times, and more.
Due to their excellent strength, weather resistance, and other benefits, structural adhesives are often used as an alternative to mechanical fasteners. This eliminates the holes and visible protrusions that mechanical fasteners cause, creating a smooth, aesthetically pleasing joint with an evenly distributed stress load.
Common Adhesive Types
Structural adhesives deliver a wide range of performance capabilities, which vary based on type. Polyurethane, epoxy, and acrylic adhesives are some of the most commonly used varieties. Learn more about their key characteristics below.
Polyurethane
3M’s polyurethane adhesives, also referred to as PUR adhesives, deliver structural strength with hot melt speed for a range of applications. They are highly resistant to vibration, impacts, and extreme temperatures, but are sensitive to moisture in their uncured state. PUR adhesives are compatible with most plastics as well as rubber, concrete, and wood. The adhesive hardens in as little as 2 to 120 minutes, resulting in a flexible bond. Since the curing process generates small amounts of carbon dioxide, small bubbles may be present throughout the bond line.
Epoxy
Out of all the types of structural bonding products, epoxy adhesives offer the highest strength and durability. They are highly resistant to weather, extreme temperatures, and solvents. 3M epoxy structural adhesives are available in two types: a traditional two-part variety that requires mixing and a one-part heat-cured variety. In general, epoxy adhesives are compatible with wood, concrete, metal, as well as some plastics and rubbers. One-part, heat-cured epoxy is used in metal-to-metal bonding applications, while 3M two-part epoxies are compatible with other substrates.
Acrylics
3M acrylic adhesives are two-part adhesives that are easy to use and offer high impact resistance. While their bond strength is not as high as epoxy products, acrylic adhesives cure faster, have a long shelf life, and bond many materials, including metals, plastics, and painted surfaces. Unlike many other types of structural adhesives, acrylics tolerate unprepared or oily surfaces well, eliminating most prep work. 3M’s new line of acrylic adhesives are low odor, fast curing, and offer improved impact resistance.
Benefits of 3M Structural Adhesives
3M structural adhesives deliver a wide range of performance capabilities, with benefits extending far beyond strength alone. In addition to their user-friendly packaging and easy-to-use applicators, these products offer numerous additional advantages, including:
- Eliminate the cost and labor associated with mechanical fastening methods
- Achieve uniform weight distribution
- Safely bond dissimilar substrate materials
- Fill large gaps between parts
- Create more lightweight assemblies
Key Applications of 3M Structural Adhesives
Structural adhesives from 3M are trusted by many of the world’s most demanding industries. Some of the most common applications include:
- Aerospace. Structural adhesives create more lightweight, corrosion-resistant aerospace assemblies. They are often used to join metal and composite aircraft structural parts.
- Automotive. Chassis components, body panels, and interior parts can all be joined by structural adhesives, reducing vehicle weight and improving fuel efficiency.
- Construction. The construction industry relies on structural adhesives to bond glass, metal, and other materials. They can be used to bond ceramic tiles, masonry, panels, doors, and much more.
- Electronics. Due to their superior vibration resistance and structural stability, structural adhesives are used in PCB manufacturing, device housings, and much more.
- Renewable energy. The strong, weather-resistant bonds that structural adhesives create are ideal for assembling wind turbine blades and solar panels.
3M Structural Adhesives
Integral Products carries a full range of 3M structural adhesive products, with solutions that include:
- 3M™ Scotch-Weld™ EC-2214 Epoxy Adhesives. This one-part epoxy paste is designed for metal-to-metal bonding as well as high-temperature plastics, including polyester, phenolics, and fiberglass-reinforced plastic. It comes in several formulas, including regular, high-density, high-temperature, and a newly formulated high-temperature version.
- 3M™ Scotch-Seal™ 1252 Tamper-Proof Sealants. Scotch-Seal 1252 is a one-part, quick-drying formula intended for application over adjustable or removable parts. After curing, any break in the seal indicates that movement or tampering has occurred. This product is frequently used in the electronics and aerospace industries to protect settings and equipment calibrations. It is also used during product assembly to ensure components are not accidentally accessed or adjusted. Within 20 seconds of application, Scotch-Seal 1252 is ready to accept ink from an inspector’s approval stamp.
- 3M™ Scotch-Weld™ EC-2216 Epoxy Adhesives. This two-part epoxy adhesive cures at room temperature, delivering high shear and peel strength. Scotch-Weld EC-2216 adhesive is certified for aerospace and aircraft applications. It comes in colors that include white, gray, amber, and translucent.
- 3M™ Scotch-Weld™ EC-2615 B/A and B/A LW (Long Work Life) Epoxy Adhesives. These 2-component epoxy adhesives cure at room temperature, creating a resilient, impact-resistant bond. EC-2615 epoxy adhesives are compatible with many metal and plastic substrates.
- 3M™ Scotch-Weld™ EC-3333 B/A Epoxy Adhesives. EC-333 B/A is a two-part epoxy adhesive with a 20-minute curing time, which allows fit adjustments to be carefully made before setting. This adhesive cures at room temperature or with heat and adheres well to plastic and metal substrates.
- 3M™ Scotch-Weld™ EC-3587 Structural Adhesives. This two-part polyurethane adhesive offers excellent adhesion to metal and plastic substrates. It cures at room temperature or with heat, forming a resilient, impact-resistant bond. EC-3587 is suitable for structural adhesive applications as well as in fairing compound and void filler applications.
- 3M™ Scotch-Weld™ DP8610NS Flexible Acrylic Adhesives. A low-odor, non-flammable acrylic adhesive with spacer beads to control bond line thickness and high tensile elongation (200%) at break. Its non-sag formula resists running, cures at room temperature, and is ideal for bonding metals, plastics, and composites where vibration resistance and flexibility are critical.
- 3M™ Scotch-Weld™ DP810 Low Odor Acrylic Adhesives. A two-part, 1:1 mix ratio adhesive that provides tough, durable bonds with less odor than traditional acrylics. It delivers excellent shear and peel strength, good impact resistance, and bonds quickly to metals, ceramics, rubbers, plastics, and wood with minimal surface preparation.
3M Structural Adhesives at Integral Products
As a trusted supplier of 3M adhesives, Integral Products offers fast access to the high-performance solutions that demanding industries depend on. Our 3M structural adhesive products support a wide variety of applications, including aerospace, construction, electronics, and more. Integral Products is ISO 9001:2015 certified and offers just-in-time distribution to businesses of any size.
If you have any questions about our products or services, contact our team for assistance. 3M’s innovative structural adhesives are designed to make bonding applications faster, more reliable, and more cost-effective. Experience all of the benefits for yourself by requesting a quote today.