LOCTITE 5188
Harmonization Code : 3506.91.90.99 | Prepared glues and other prepared adhesives, not elsewhere specified or included; products suitable for use as glues or adhesives, put up for retail sale as glues or adhesives, not exceeding a net weight of 1 kg ; Adhesives based on polymers of headings 3901 to 3913 or on rubber; Other ; Other

Main features
- Flexible Cured Sealing
- Strong Aluminum Adhesion
- High-Viscosity Placement Control
Product Description
LOCTITE® 5188™ is a single-component, medium-strength anaerobic form-in-place gasketing product for close-fitting rigid metal flange connections. It cures between mating metal surfaces in the absence of air and is particularly suited to aluminum substrates. The flexible formulation maintains flexibility after high-temperature exposure, tolerates minor oil contamination on flange surfaces, and provides resistance to low pressures immediately after assembly. Typical uses include sealing gearboxes, engine casings, and other rigid metal flanged assemblies.
Key features
- Flexible flange sealing: Maintains flexibility after exposure to elevated temperatures.
- Aluminum performance: Provides strong adhesion on close-fitting aluminum flange surfaces.
- One-component application: Requires no mixing and can be dispensed manually or with automated equipment.
TDS, SDS & Technical Documents
Technical Specifications
General Properties
Physical Properties
Thermal Properties
Mechanical Properties
Additional Information
As-supplied / before-processing properties
Typical properties of the uncured material; values are reference data rather than guaranteed product specifications.
| Property | Value | Unit | Method / condition |
|---|---|---|---|
| Technology | Acrylic | — | Uncured material |
| Chemical type | Dimethacrylate ester | — | Uncured material |
| Appearance | Red viscous product | — | Uncured material |
| Components | One component | — | No mixing required |
| Fluorescence | Positive | — | Under ultraviolet light |
| Specific gravity | 1.1 | — | At 25°C |
| Viscosity | 11,000–32,000 | mPa·s | Cone and plate, 25°C; PK 100, PK 1, 2° cone at 20 s⁻¹ |
After-processing / final-state properties
Typical cured-material properties depend on the stated cure schedule, substrate, specimen, and test method.
| Property | Value | Unit | Method / condition |
|---|---|---|---|
| Glass-transition temperature | 105 | °C | Typical cured-material property |
| Elongation at break | 186 | % | Typical cured-material property |
| Tensile strength at break | 4.24 | N/mm² | Typical cured-material property |
| Tensile modulus | 4.17 | N/mm² | Typical cured-material property |
| Lap-shear strength | 9.2 | N/mm² | Grit-blasted mild steel; cured 72 hours at 22°C |
| Lap-shear strength | 7.0 | N/mm² | Aluminum; cured 72 hours at 22°C |
| Lap-shear strength | 7.8 | N/mm² | Grit-blasted mild steel; cured 168 hours at 22°C |
| Lap-shear strength | 8.0 | N/mm² | Aluminum; cured 168 hours at 22°C |
| Maximum sealed induced gap | 0.25 | mm | Annular gasket on mild steel; tested to 1.3 MPa after curing |





















