Sikaflex 221 Black 600 ml black, one-component adhesive, polyurethane sealant for metal, paint coatings, ceramics

Discounted product – Expiry date: 01/10/2025

Sikaflex-221 black 600 ml is a one-component, non-sag polyurethane sealant and adhesive designed for durable sealing and bonding of metals, painted substrates, ceramics and plastics. It cures by ambient moisture to form flexible, UV- and vibration-resistant joints that withstand corrosion and ageing.

Benefits and Unique Features

• One-component – ready to use, no mixing required
• Non-sag formulation – stays in place on vertical and overhead surfaces
• Minimal shrinkage (5 %) for precise, gap-filling joints
• Excellent ageing and UV resistance
• Sandable and paintable after full cure
• Meets EN 45545-2 R1/R7 HL3 for rail applications
• Low odour for improved working comfort

Properties and Applications

• Chemical base: one-component polyurethane
• Colour: black
• Density (uncured): 1.3 kg/l
• Application temperature: +5 °C to +40 °C
• Open time: 45 min at 23 °C/50 % RH
• Skin-over time: 60 min at 23 °C/50 % RH
• Shrinkage: 5 %
• Shore A hardness: 40
• Tensile strength: 1.8 MPa
• Elongation at break: 500 %
• Tear propagation resistance: 7 N/mm
• Service temperature: –50 °C to +90 °C (24 h), briefly +120 °C/+140 °C
• Applications: sealing and bonding of vehicle bodies, panels, rail cars, metals, ceramics and plastics

Technical Specifications

Instructions for Use

1. Ensure all substrates are clean, dry and free of grease, oil and dust.
2. Shake the cartridge thoroughly before use and fit into a caulking gun.
3. Apply at +5 °C to +40 °C; optimal performance at +15 °C to +25 °C.
4. Assemble parts within the open time (45 min) to achieve full adhesion.
5. Smooth the joint before skin-over time (60 min) using Sika Tooling Agent N or a soap-water solution.
6. Remove uncured sealant with Sika Remover-208; cured material must be removed mechanically.
7. Clean tools and skin with Sika Cleaner-350H and water immediately after use.

Storage Recommendations

Store in a cool, dry place at +5 °C to +25 °C, away from direct sunlight and frost. Keep container tightly closed in its original packaging.