Sikaflex -252 Elastic 1-Component PU Bonding Adhesive for Vehicle Assembly
An elastic 1-component polyurethane adhesive especially designed for bonding large components in vehicle assembly. Bonds well to a variety of substrates such as coated metal, GRP, ceramic materials and plastics.
Professional Use — Suitable for experienced professional users only. Tests with the actual substrates — particularly plastics prone to stress cracking — and site conditions must be conducted to confirm adhesion and material compatibility before full application.
P.O Box 2806, Industrial Area 15, Sharjah UAE — expert coordination, authentic supply, site-ready delivery.
What is Sikaflex-252?
Sikaflex-252 is an elastic, 1-component polyurethane adhesive especially designed for bonding large components in vehicle assembly. It bonds well to a variety of substrates such as coated metal, GRP, ceramic materials and plastics, and is suitable for assemblies subject to dynamic stresses.
Ideal substrates include timber, metals — particularly aluminium (including anodised components), sheet steel (including phosphated, chromated and galvanised components), metal primers and 2-component paint coatings — ceramic materials and plastics. It cures on exposure to atmospheric moisture to form a durable, elastic, vibration-damping joint. Suitable for experienced professional users only; test with the actual substrates, particularly plastics prone to stress cracking, before use.
Bonds To
Key Benefits
- Bonds a wide variety of substrates — works with coated metal, GRP, ceramic materials and plastics as an excellent adhesive.
- Withstands high dynamic stresses — handles high stresses and shocks without breaking the bond.
- Good gap-filling — fills uneven spaces between parts to create a secure seal.
- Can be painted — suitable for visible joints, giving a clean finish.
- Vibration-damping — absorbs vibration and reduces noise in vehicles and structures.
- Electrically non-conductive — prevents galvanic corrosion between dissimilar metals.
Cured Mechanical Properties
Chemical & Physical Properties
| Base Chemistry | 1-component polyurethane |
| Colour | Black, White, Grey |
| Cure Mechanism | Moisture |
| Density (uncured) | 1.2 kg/l (depending on colour) |
| Non-Sag Properties | Good |
| Application Temperature | 10 – 35 °C (ambient) |
| Skin Time | 40 minutes A |
| Open Time | 35 minutes A |
| Shore A Hardness | 50 |
| Tear Propagation Resistance | 7 N/mm |
| Shelf Life | 12 months B |
A — 23 °C / 50 % r.h. · B — Storage below 25 °C.
Curing Speed
| 30 °C / 80% r.h. | 4–5 mm after day 1, up to 10 mm after 2–3 days |
| 23 °C / 50% r.h. | 2–3 mm after day 1, up to 8 mm after 4–5 days |
| 10 °C / 50% r.h. | 1 mm after day 1, up to 8 mm after 10 days |
Pack Sizes & Chemical Resistance
| Pack Sizes | Cartridge (300 ml), Unipack (400 ml & 600 ml), Pail (23 L), Drum (195 L) |
| Good Resistance | Fresh water, seawater, diluted acids & caustic solutions |
| Temporary Resistance | Fuels, mineral oils, vegetable & animal fats/oils |
Application Guide
Follow these steps for reliable bonding and elastic sealing with Sikaflex-252. The optimum temperature for both substrate and adhesive is between 15 °C and 25 °C. Always refer to the current Sika Product Data Sheet.
Surface Preparation
Surfaces must be clean, dry and free from grease, oil and dust, and should be treated according to the specific nature of the substrate — correct preparation is crucial for a long-lasting bond. Use the appropriate Sika primer/activator for the substrate where required.
Application
The product can be processed within its stated ambient application range (10–35 °C), with the understanding that reactivity and application properties change with temperature; the optimum is 15–25 °C for both substrate and adhesive. Bring the product down to ambient temperature before use, as its viscosity increases in the cold. Apply in a triangular bead profile to achieve a uniform bondline thickness, using manual, pneumatic or dispensing equipment such as electric-driven piston guns or pumps.
Tooling & Finishing
Tool and finish the sealant before a skin forms over the surface. Sika Tooling Agent N is recommended; any alternative brands should be tested before application for compatibility and suitability.
Overpainting
Painting is possible after skin formation. Where the paint requires a baking process, ensure the sealant is fully cured first. Paints such as 1C-PUR and 2C-Acrylic based systems are usually suitable — conduct preliminary trials under the actual manufacturing conditions to confirm.
Removal
Cured product can be removed physically. Uncured product can be removed using Sika Remover-208 or an alternative suitable solvent.
Chemical Resistance
Once cured, Sikaflex-252 offers general resistance to fresh water, seawater, diluted acids and caustic solutions, with temporary resistance to fuels, mineral oils and vegetable or animal fats and oils. See the Cautions below for chemicals it does not resist.
Open Time in Heat
Parts must always be joined within the open time — the UAE's hot, humid climate shortens it. Never bring bonding parts together once the adhesive has formed a skin.
Chemical Limitations
Not resistant to certain chemicals — organic acids, glycolic alcohol, concentrated mineral acids, caustic solutions or solvents. Avoid exposure to these in service.
Skin Contact
If hands or skin are exposed, clean immediately with hand wipes (Sika Cleaner-350H recommended) or a suitable industrial hand cleaner and water. Never use solvents on the skin.
Paint Elasticity
Paints have lower elasticity than the sealant, which could lead to cracking of the paint over the joint area. Select a flexible paint system where movement is expected.
Related Products
Sikaflex-252 sits within Sika's polyurethane assembly-adhesive range and works with Sika primers and activators for reliable bonding. Explore the related products below. All stocked by Highway BMT.