LOCTITE AA 3381
Harmonization Code : 3907.30.00.40 | Epoxy Mold Compounds containing by weight more than 70 % silicon dioxide

Main features
- Fast 365 nm Light Fixturing
- High-Elongation Glass Joint Sealing
- Dissimilar Rigid-Substrate Bonding
Product Description
LOCTITE AA 3381 is a one-component, medium-viscosity acrylated urethane adhesive for UV-light bonding, potting, and sealing. The translucent colorless liquid requires no mixing and is intended primarily for glass-to-metal joints exposed to thermal cycling and environmental conditions. It also bonds dissimilar rigid substrates and reaches fixture strength in 15 seconds or less under the specified 365 nm light conditions. The cured material combines Shore A hardness of at least 72 with 330% elongation. Block-shear performance is characterized for glass-to-glass, glass-to-steel, glass-to-aluminum, and polycarbonate assemblies. Applications include disposable medical-device assembly.
Key features
- Glass-to-Metal Joint Sealing: The product is intended for potting and sealing glass-to-metal joints exposed to thermal cycling and environmental conditions.
- High-Elongation Cure: The cured material provides 330% elongation with Shore A hardness of at least 72.
- Fast 365 nm Fixture: Fixture strength develops in 15 seconds or less under the listed 365 nm light conditions.
Applications / Suitable for
- Potting and sealing glass-to-metal joints
- Bonding dissimilar rigid substrates
- Disposable medical-device assembly
TDS, SDS & Technical Documents
Technical Specifications
General Properties
Physical Properties
Chemical Properties
Mechanical Properties
Electrical Properties
Additional Information
As-supplied / before-processing properties
Typical values for the uncured or as-supplied product unless otherwise noted.
| Property | Value | Unit | Method / condition |
|---|---|---|---|
| Appearance | Translucent colorless | - | Uncured |
| Specific gravity | 1.08 | - | 25 deg C |
| Viscosity | 3,600 to 6,600 | mPa s | Brookfield RVT, spindle 4, 20 rpm, 25 deg C |
After-processing / final-state properties
Typical values for the cured product under the listed methods and conditions.
| Property | Value | Unit | Method / condition |
|---|---|---|---|
| Shore hardness | >=72 | Durometer A | ISO 868; cured 30 seconds at 100 mW/cm^2 and 365 nm, D bulb |
| Elongation at break | 330 | % | ISO 527-3; same cure |
| Tensile strength at break | 7.91 | N/mm^2 | ISO 527-3; same cure |
| Tensile modulus | 18.6 | N/mm^2 | ISO 527-3; same cure |
| Dielectric breakdown strength | 37 | kV/mm | IEC 60243-1; same cure |
| Block shear strength | 4.2 | N/mm^2 | ISO 13445; glass to glass; 0.127 mm gap; same cure |
| Block shear strength | 3.5 | N/mm^2 | ISO 13445; glass to steel; 0.127 mm gap; same cure |





















