3M™ 2123 Removable Insulating Resin

3M™ 2123 Removable Insulating Resin, High-Performance Electrical Protection

The 3M™ 2123 Removable Insulating Resin effectively protects your electronic components against moisture, vibrations, and contaminants.

Its major advantage: it remains removable, which allows for circuit servicing without having to sacrifice everything.

Ideal for encapsulating electronic circuit boards, it offers durable, high-performance electrical insulation in demanding environments.

What is the 3M™ Scotchcast™ 2123 removable insulating resin?

The 3M™ Scotchcast™ 2123 is a two-component polyurethane potting resin designed to protect electrical connections and components against moisture, mechanical shock, and contaminants.

Its special feature: it remains removable after polymerization. Unlike conventional epoxy resin, the 2123 can be mechanically removed without destroying the encapsulated components.

This is a major asset for any application requiring maintenance, replacement, or subsequent inspection of the encapsulated elements.

Composition and polyurethane technology of the 3M™ 2123

The two-component polyurethane formula combines an isocyanate prepolymer and a polyol. Mixing them triggers a cross-linking reaction at room temperature, without requiring an oven or special equipment.

Once cured, the resin forms a flexible elastomer, not a rigid block. This flexibility absorbs vibrations and thermal expansion, which reduces mechanical stress on solder joints and wires.

Here is what this technology provides in practical terms:

• High dielectric strength, reliable electrical insulation for low-voltage applications
• Moisture resistance, effective protection in humid or outdoor environments
• Mechanical flexibility, no cracking under vibrations
• Removability, removal possible when cold without aggressive solvents

Feature	3M™ Scotchcast™ 2123 (polyurethane)	3M™ Scotchcast™ 2131 (epoxy)	3M™ Scotchcast™ 8 (rigid epoxy)
Technology	Two-component polyurethane	Two-component epoxy	Two-component epoxy
Flexibility after curing	Flexible elastomer	Semi-rigid	Rigid
Removable	Yes	No	No
Vibration resistance	Excellent	Good	Limited
Typical application	Junctions, serviceable enclosures	Permanent low-voltage potting	Permanent high-voltage potting

Technical properties and typical characteristics of 3M™ 2123 resin

The 3M™ 2123 removable insulating resin is a two-component epoxy resin designed for the encapsulation and protection of electronic and electrical components. Its special feature: it remains removable after polymerization, which distinguishes it from permanent potting resins.

Once polymerized, it offers excellent resistance to mechanical shock and vibrations. It effectively protects against moisture, dust, and common chemical contaminants.

Its high dielectric strength guarantees reliable electrical insulation, even in demanding environments. It is suitable for low- and medium-voltage applications.

The mixture is relatively fluid before setting, which facilitates filling complex cavities and fully coating circuit boards without air bubbles.

Typical characteristics:

• Chemical base: two-component epoxy
• Color after polymerization: translucent amber yellow
• Service temperature: generally -40 °C to +130 °C
• Volume resistivity: > 10¹⁴ Ω·cm
• Removability: possible by cutting or dissolution depending on the process
• Working time: approximately 30 to 60 minutes at 23 °C

Product	Type	Removable	Max. temperature	Typical usage
3M™ 2123	Two-component epoxy	✔ Yes	~130 °C	Electronic encapsulation, maintenance, prototyping
3M™ Scotchcast™ 2130	Two-component epoxy	✘ No	~155 °C	Permanent potting, medium-voltage cables
Electrolube ER2220	Two-component epoxy	✘ No	~120 °C	PCB encapsulation, common industrial use
Dow Sylgard™ 184	Two-component silicone	✔ Partial	~200 °C	Optics, sensors, high temperature

The removability criterion is decisive for applications requiring subsequent interventions on components. This is precisely where the 3M™ 2123 gains the advantage over definitive potting resins.

Applications and areas of use for 3M™ Scotchcast™ 2123 resin

The 3M™ Scotchcast™ 2123 removable insulating resin is designed to protect electrical components exposed to moisture, vibrations, and chemical contaminants.

Its removable nature distinguishes it from conventional epoxy resins: it can be removed mechanically without destroying the encapsulated components, which facilitates repairs and maintenance.

Protection of electrical connections and junction boxes

The 3M™ 2123 applies directly to junction boxes, cable splices, and low-voltage connectors. It forms a rigid yet extractable shell around sensitive elements.

Here are the main areas of application:

• Automotive industry: protection of wire harnesses and connectors exposed to the elements
• Outdoor lighting: sealing of junction boxes in humid environments
• Telecommunications: encapsulation of buried or aerial cable splices
• Railway industry: insulation of connections subject to vibrations
• Renewable energies: protection of photovoltaic and wind power connections

Unlike permanent epoxy resins like the 3M™ Scotchcast™ 2130, the 2123 remains removable when cold, without solvent or heat. This is a decisive advantage for installations requiring regular intervention.

Product	Type	Removable	Rigidity	Typical usage
3M™ Scotchcast™ 2123	Polyurethane	✔ Yes	Semi-rigid	Low-voltage junctions, frequent maintenance
3M™ Scotchcast™ 2130	Epoxy	✘ No	Rigid	Permanent encapsulation, harsh environments
3M™ Scotchcast™ 4411	Polyurethane	✔ Yes	Flexible	Flexible cables, mobile connectors

3M™ 2123 removable resin vs. other insulating resins: comparison table

The 3M™ 2123 removable insulating resin clearly stands out from conventional epoxy or polyurethane resins. Its main advantage: it remains removable after polymerization, which simplifies maintenance and repair operations.

Here is a direct comparison with the most common insulating resins on the market.

Feature	3M™ 2123	Epoxy resin (e.g., 3M™ Scotchcast 2131)	Polyurethane resin (e.g., Electrolube UR5528)
Removable	Yes	No	No
Rigidity after setting	Flexible to semi-rigid	Rigid	Flexible
Dielectric strength	High	Very high	High
Moisture resistance	Good	Excellent	Very good
Ease of repair	Excellent	Low (destructive)	Low to medium
Typical applications	Prototyping, maintenance, small series	Definitive encapsulation, high voltage	Consumer electronics, vibrations

The 3M™ Scotchcast 2131 offers superior insulation for definitive applications. But as soon as any subsequent intervention is anticipated, the 2123 remains the logical choice.

In summary, the 3M™ 2123 is ideal when reversibility takes precedence over rigidity. It avoids sacrificing a component to gain access to a circuit.

Implementation and tips for using the 3M™ 2123 resin

The 3M™ 2123 removable insulating resin applies directly to the electronic components and connections to be protected. Its viscosity is suitable for application with a brush, a syringe, or by partial immersion.

Before any application, the surface must be clean, dry, and degreased. Any trace of moisture or residual solder flux can compromise adhesion and insulating performance.

The 3M™ 2123 resin polymerizes at room temperature. The complete drying time varies according to the thickness of the applied layer and ambient conditions (temperature, humidity). A thin layer dries faster and offers better penetration in complex zones.

Its main asset: it remains removable. Unlike a conventional epoxy resin, it can be removed mechanically or with the help of a suitable solvent, without destroying the component. This facilitates maintenance and rework operations.

Some best practices to remember:

• Apply in thin, successive layers rather than in a single thick layer
• Work in a ventilated environment
• Protect areas not concerned before application
• Respect the drying time between two layers
• Store the product away from heat and humidity

At Dagobert Industrie, we recommend this product for interventions on electronic boards, connection terminals, and assemblies requiring temporary or reversible protection.

FAQ - 3M™ Scotchcast™ 2123 removable insulating resin

1. What distinguishes the Scotchcast™ 2123 from a conventional epoxy resin?

The 3M™ Scotchcast™ 2123 is a removable polyurethane resin, unlike epoxy resins which polymerize irreversibly. Once cured, it can be removed mechanically without destroying the encapsulated component.

2. In what cases is this resin used?

It is used for coating and protecting electrical connections: junction boxes, cable splices, sensors, electronic boards exposed to moisture or vibrations. It is suitable for both workshop and field use.

3. Is the resin really removable after hardening?

Yes. The flexibility of the polyurethane allows the resin to be cut or torn off without damaging the conductors. This is the key advantage over rigid resins: an intervention or repair remains possible after encapsulation.

4. What are the electrical performances of the Scotchcast™ 2123?

The resin offers high dielectric strength and excellent resistance to moisture, fluids, and common chemical agents. It is suitable for low-voltage applications up to 600 V.

5. How is the resin prepared and applied?

The Scotchcast™ 2123 comes in a pre-mixed two-component kit. Simply mix the two components, pour into the mold or directly onto the connection, then let it harden at room temperature. No special equipment is required.

6. At Dagobert Industrie, for which sectors do you recommend this product?

At Dagobert Industrie, we recommend it mainly for industry, renewable energies, rail transport, and outdoor installations. Everywhere where the maintainability of electrical equipment is an unavoidable constraint.