LOCTITE EA 3981
Harmonization Code : 5906100000 | Adhesive tape of a width not exceeding 20cm
Main features
- One-Component No-Mix Adhesive
- Heat Cure as Low as 100 deg C
- Disposable-Needle/Syringe/Lancet Cannula Bonding
Product Description
LOCTITE® EA 3981 is a one-component, heat-cure epoxy adhesive developed for assembling disposable medical devices. The translucent, slightly amber liquid requires no mixing and fluoresces under ultraviolet light to support inspection during production. It cures at temperatures as low as 100°C and bonds plastics, metals, and glass. The product is specifically designed for bonding stainless steel cannulae into hubs, syringes, and lancets used in needle assemblies. Its combination of rapid thermal curing, adhesion across multiple substrate types, and resistance to environmental exposure supports high-speed medical-device assembly processes.
Key features
- One-component epoxy: Requires no mixing before application, simplifying material preparation and dispensing.
- Rapid heat cure: Cures at temperatures as low as 100°C, with documented cure schedules for production processing.
- UV fluorescence: Produces a positive response under ultraviolet light to support adhesive-presence inspection.
Applications / Suitable for
- Bonding stainless steel cannulae into plastic hubs
- Needle, syringe, and lancet assemblies
- Assembly of disposable medical devices
- Bonding plastics, metals, and glass
TDS, SDS & Technical Documents
Technical Specifications
General Properties
Physical Properties
Mechanical Properties
Chemical Properties
Additional Information
As-supplied / before-processing properties
Typical properties of the adhesive before heat curing.
| Property | Value | Unit | Method / condition |
|---|---|---|---|
| Technology | Epoxy | — | As supplied |
| Components | One component | — | Requires no mixing |
| Appearance | Translucent, slightly amber liquid | — | Uncured material |
| Fluorescence | Positive | — | Under UV light |
| Specific gravity | 1.14 | — | At 25°C |
| Viscosity | 4,000–6,000 | mPa·s (cP) | Brookfield SSA-RVT, 25°C; spindle 14, 50 rpm |
| Optimal storage temperature | 2–8 | °C | Store unopened in a dry location |
After-processing / final-state properties
Typical properties of the heat-cured adhesive under the stated cure and test conditions.
| Property | Value | Unit | Method / condition |
|---|---|---|---|
| Shore hardness | ≥70 | Durometer D | ISO 868; cured 30 minutes at 120°C |
| Glass transition temperature | 56 | °C | ASTM E 228; cured 30 minutes at 125°C |
| Coefficient of thermal expansion, below Tg | 62 × 10-6 | K-1 | ISO 11359-2; cured 30 minutes at 125°C |
| Coefficient of thermal expansion, above Tg | 193 × 10-6 | K-1 | ISO 11359-2; cured 30 minutes at 125°C |
| Elongation at break | 2.98 | % | ISO 527-3; cured 30 minutes at 125°C |
| Tensile strength | 62 | N/mm² | ISO 527-3; cured 30 minutes at 125°C; 8,970 psi |
| Tensile modulus | 2,383 | N/mm² | ISO 527-3; cured 30 minutes at 125°C; 345,500 psi |
| Lap shear strength | ≥13.8 | N/mm² | Etched aluminum, 0.125 mm gap; cured 30 minutes at 120°C; ≥2,000 psi |
