LOCTITE 438
Harmonization Code : 3907.30.00.40 | Epoxy Mold Compounds containing by weight more than 70 % silicon dioxide
Main features
- Black Rubber-Toughened Bonding
- Enhanced Shock and Peel Resistance
- Low-Viscosity Multi-Material Assembly
Product Description
LOCTITE 438 is a black, one-part, low-viscosity, rubber-toughened ethyl cyanoacrylate instant adhesive for bonding metals, plastics, rubbers, and selected porous materials. Its black color makes adhesive placement visible, while the toughened formulation combines increased flexibility and peel strength with resistance to shock. A viscosity of 100 to 250 mPa s supports thin bondlines and rapid wetting. Fixture time ranges from under 5 seconds on nitrile rubber and balsa wood to 30 to 60 seconds on common metal substrates under the specified conditions.
Key features
- Black visible bondline: The black liquid provides clear visual contrast for adhesive placement and cured bond identification.
- Rubber-toughened performance: Increased flexibility and peel strength are combined with enhanced resistance to shock.
- Low-viscosity multi-material cure: A 100 to 250 mPa s viscosity supports rapid bonding across tested metals, plastics, rubbers, and porous materials.
Applications / Suitable for
- Visible black bonding of metals and plastics
- Shock- and peel-resistant rubber bonding
- Bonding selected wood, paper, leather, and fabric
TDS, SDS & Technical Documents
Technical Specifications
General Properties
Thermal Properties
Physical Properties
Mechanical Properties
Electrical Properties
Curing Conditions
Additional Information
As-supplied / before-processing properties
Typical values for the product before cure, application, or assembly.
| Property | Value | Unit | Method / condition |
|---|---|---|---|
| Appearance | Black liquid | - | Uncured |
| Chemical type | Ethyl cyanoacrylate | - | As supplied |
| Components | One part | - | No mixing required |
| Specific gravity | 1.1 | - | 25 deg C |
| Viscosity | 100 to 250 | mPa s | Cone and plate, 25 deg C, shear rate 1,000 s^-1 |
| Cure mechanism | Humidity | - | Atmospheric moisture |
After-processing / final-state properties
Typical values for the cured or installed product under the listed conditions.
| Property | Value | Unit | Method / condition |
|---|---|---|---|
| Fixture time, nitrile rubber | <5 | s | 22 deg C, 50% RH; time to 0.1 N/mm^2 shear strength |
| Fixture time, ABS | 10 to 20 | s | 22 deg C, 50% RH; time to 0.1 N/mm^2 shear strength |
| Fixture time, aluminum | <=60 | s | Isopropanol-wiped aluminum, 22 deg C, 50% RH |
| Glass transition temperature | 130 | deg C | ISO 11359-2; cured 24 h at 22 deg C |
| Lap shear strength, grit-blasted steel | 19 | N/mm^2 | ISO 4587; cured 24 h at 22 deg C |
| 180-degree peel strength, grit-blasted steel | 4 | N/mm | ISO 8510-2; cured 48 h at 22 deg C |
| Side impact resistance, aluminum | >=4 | J | Cured 24 h at 22 deg C |
