3M™ 3789 Hot Melt Adhesive

3M 3789 Hot Melt Adhesive: High-performance adhesive for industrial applications

The 3M 3789 hot melt adhesive is a versatile, high-performance adhesive designed for demanding industrial environments. It offers a fast set time and excellent mechanical strength on a wide range of materials.

Compatible with 3M hot melt applicators, it applies easily to plastics, wood, textiles, and metals. Its high adhesive strength ensures durable bonds, even under stress.

Ideal for both mass production and point repairs, the 3789 is a reliable standard in industrial workshops.

Presentation of the 3M 3789 hot melt adhesive

The 3M 3789 hot melt adhesive is a versatile adhesive designed for demanding industrial applications. It comes in the form of a solid stick that is melted and then applied hot via a compatible hot melt gun.

Its strong point: fast and solid adhesion on a wide range of materials. Wood, plastics, foams, fabrics, cardboard, light metals, it covers most bonding needs in workshops or production.

Composition and technology of the 3789 adhesive

3M 3789 is formulated based on ethylene vinyl acetate (EVA), a thermoplastic resin recognized for its flexibility and mechanical strength after cooling.

This EVA chemistry gives it an application temperature of around 190 °C, a short open time, and a fast set time. Ideal for sustained production rates.

It also offers good resistance to shocks and vibrations, which distinguishes it from cyanoacrylate or epoxy adhesives in environments subject to repeated mechanical stress.

• Chemical base: EVA (ethylene vinyl acetate)
• Application temperature: ~190 °C
• Setting: fast (a few seconds)
• Compatible substrates: wood, cardboard, plastics, foams, textiles, light metals
• Resistance: shocks, vibrations, moderate traction

Product	Manufacturer	Chemical base	Application temp.	Strengths	Typical use
3M 3789	3M	EVA	~190 °C	Versatility, fast setting, good mechanical strength	General industry, packaging, assembly
3M 3748	3M	EVA	~177 °C	Lower temperature, suitable for heat-sensitive materials	Foams, delicate textiles
Tec Bond 261	Power Adhesives	Polyolefin	~200 °C	Excellent moisture resistance	Outdoor applications, damp wood
Henkel Technomelt PA 6208	Henkel	Polyamide	~210 °C	High thermal and chemical resistance	Automotive, electronics

Technical properties and characteristics of the 3M 3789

The 3M 3789 is a polyolefin hot melt adhesive formulated for demanding industrial applications. It comes in the form of sticks compatible with standard hot melt guns.

Its application temperature is around 190 °C, with a high softening point that guarantees good performance in hot service conditions. The open time is short, which favors sustained production rates.

It offers excellent adhesion on polyolefins (PP, PE), materials known to be difficult to bond without surface treatment. This is one of its distinctive assets compared to standard EVA adhesives.

The 3789 is highly resistant to light oils and greases, making it suitable for industrial environments where surface contamination is frequent.

Characteristic	3M 3789 (Polyolefin)	3M 3762 (EVA)	3M 3748 (High-perf EVA)
Chemical base	Polyolefin	EVA	EVA
PP/PE adhesion	Excellent	Low	Low
Application temperature	~190 °C	~177 °C	~177 °C
Grease resistance	Good	Average	Average
Typical uses	Automotive, PP packaging, electronics	Cardboard, wood, textile	General assembly, paper

The translucent natural color of the bead allows for a neat finish on visible assemblies. The cured joint remains flexible at low temperatures, preventing cracking in cold environments.

Applications and materials compatible with the 3M 3789 hot melt adhesive

The 3M 3789 hot melt adhesive is a versatile polyolefin-based adhesive. It adheres to a wide range of materials, including low surface energy surfaces that most adhesives struggle to bond to.

This is what distinguishes it from standard EVA-based hot melt adhesives. Where EVA fails on polypropylene or polyethylene, the 3789 holds.

Compatible materials:

• Polypropylene (PP) and polyethylene (PE)
• Wood, cardboard, paper
• Foams and textiles
• Metal (steel, aluminum)
• Certain rigid plastics (ABS, PVC)

Typical applications:

• Assembly of plastic parts in the automotive industry
• Fixing of foams and interior trim
• Product packaging on difficult substrates
• Assembly of components in consumer electronics
• Bonding of panels and profiles in cabinetry

The 3789 is used with a standard hot melt glue gun compatible with 12 mm diameter sticks. Implementation is fast and does not require specific surface preparation in most cases.

Product	Manufacturer	Chemical base	PP/PE adhesion	Thermal resistance	Primary use
3M 3789	3M	Polyolefin	✔ Excellent	Up to ~82 °C	Low-energy plastics, automotive, packaging
3M 3762	3M	EVA	✘ Limited	Up to ~66 °C	Wood, cardboard, general use
Henkel Technomelt PA 6792	Henkel	Polyamide	✔ Good	Up to ~150 °C	High-temperature applications, metal
Bostik HM 4601	Bostik	EVA	✘ Low	Up to ~70 °C	Packaging, cardboard, paper

Comparison: the 3M 3789 versus other hot melt adhesives on the market

The 3M 3789 is a versatile copolymer-based hot melt adhesive. It stands out for its high adhesion on a wide range of substrates: plastics, metals, wood, textiles, and foams.

Compared to competing benchmarks like the Bostik H9100 or the Henkel Technomelt PA 6792, it offers a better balance between flexibility and heat resistance.

Product	Manufacturer	Chemical base	Application temp.	Thermal resistance	Strengths
3M 3789	3M	EVA Copolymer	190 °C	Up to 60 °C	Versatility, multi-substrate adhesion
Bostik H9100	Bostik	EVA	180 °C	Up to 50 °C	Good cost/performance ratio on cardboard
Technomelt PA 6792	Henkel	Polyamide	210 °C	Up to 120 °C	High thermal resistance, demanding applications
3M 3748	3M	EVA Copolymer	177 °C	Up to 50 °C	Ideal for heat-sensitive materials

Henkel's Technomelt PA 6792 goes higher in temperature, but it requires a high-temperature gun and costs more. The 3M 3789 remains easier to implement on a daily basis.

Compared to the 3M 3748, its little sister at 3M, the 3789 displays better final thermal resistance and reinforced adhesion on difficult substrates like polypropylene.

In summary, the 3M 3789 is the ideal choice when looking for a reliable, easy-to-use hot melt adhesive compatible with varied substrates, without needing extreme temperature performance.

Usage tips and best practices for the 3M 3789 adhesive

The 3M 3789 hot melt adhesive is applied with a hot glue gun compatible with standard 12 mm nozzles. Before any application, verify that the gun has reached the proper temperature.

Clean and degrease the surfaces to be bonded thoroughly. A clean and dry substrate ensures optimal adhesion and prevents premature detachment.

Apply the adhesive in a steady bead, then assemble the parts quickly. The open time is short: allow for just a few seconds before the adhesive begins to set.

Maintain light pressure on the assembly during solidification. The final strength is reached in a few minutes at room temperature.

Application temperatures and safety precautions

The 3789 is a high-temperature adhesive: the melting point is around 190 °C. Use only a gun adapted for high-temperature adhesives.

Avoid any contact of the molten adhesive with the skin. Wear heat-resistant gloves and work in a well-ventilated space to limit exposure to vapors.

Never leave the gun heating for long periods without use: the adhesive may degrade and lose its properties. Turn off the gun or switch to standby mode between applications.

Store adhesive sticks away from moisture and high temperatures. Proper storage preserves adhesive performance over the long term.

FAQ - 3M 3789 Hot Melt Adhesive

1. At what temperatures can the 3M 3789 adhesive be used?

The 3M 3789 hot melt adhesive is applied at a melting temperature of approximately 190 °C with an adapted glue gun.

It then resists service temperatures up to approximately 80 °C once the joint has solidified.

2. On which materials does the 3789 adhere?

It bonds effectively on a broad spectrum: wood, cardboard, plastics, textiles, foams, ceramics, and light metals.

Its excellent wetting properties allow it to hold even on slightly porous or irregular surfaces.

3. What is the difference between the 3M 3789 and the 3M 3762?

The 3M 3762 is an all-purpose adhesive with lower viscosity, ideal for light assemblies and delicate materials.

The 3M 3789 offers higher viscosity and superior mechanical strength, making it suited for demanding industrial applications.

4. Is the 3M 3789 compatible with all 3M glue guns?

3M 3789 adhesive sticks are available in 12 mm and 43 mm diameters. Therefore, you need a gun adapted to the correct caliber.

At Dagobert Industrie, we offer compatible 3M guns to ensure optimal application.

5. What is the open time of the 3M 3789 adhesive?

The open time, meaning the window available to position the parts before solidification, is approximately 20 to 40 seconds.

This is sufficient for most industrial assemblies, but positioning should be prepared beforehand for large surfaces.

6. Is the 3789 resistant to humidity?

Yes. Once polymerized, the joint shows good resistance to ambient humidity and water splashes.

However, for prolonged immersion or a very aggressive environment, a structural epoxy or polyurethane adhesive will be more suitable.