Sikaflex 268 High-Performance Bonding and Sealing Sealant for Rail Applications

Sikaflex®-268 is a one-component polyurethane adhesive and sealant specially developed for the rail industry. It provides outstanding performance and long-term durability in glass bonding, assembly, and sealing applications. The curing process can be accelerated using Sika Booster and Sika PowerCure systems, allowing for optimized production and installation times.

Key Advantages

✔ Outstanding weather resistance
✔ Complies with EN 45545 R1/R7 HL3 fire safety requirements
✔ Resistant to a wide range of cleaning agents
✔ Fast curing when used with Sika Booster and PowerCure systems
✔ Solvent-free formulation for safer application
✔ Excellent application and tooling properties

Applications

Sikaflex®-268 is designed for demanding rail vehicle applications, including:

• Rail vehicle assembly
• Glass bonding
• Exterior sealing joints
• Repair and maintenance work

Note: Compatibility testing and manufacturer approval are recommended before use on substrates that may be susceptible to stress cracking.

Technical Specifications

Chemical Base:
One-component polyurethane

Curing Mechanism:
Moisture curing

Color:
Black

Density:
1.3 kg/L (uncured)

Skin Formation Time:
Approximately 60 minutes (23°C / 50% RH)

Open Time:
Approximately 40 minutes (23°C / 50% RH)

Volume Shrinkage:
1%

Shore A Hardness:
55 (ISO 48-4)

Tensile Strength:
6 MPa (ISO 527)

Elongation at Break:
500% (ISO 37)

Tear Resistance:
13 N/mm (ISO 34)

Lap Shear Strength:
4.5 MPa (ISO 4587)

Service Temperature:
-50°C to +90°C

Packaging Options

• 300 ml cartridge
• 600 ml foil pack
• 23 L pail
• 195 L drum

Application and Surface Preparation

• Surfaces must be clean, dry, and free from oil, grease, and contaminants.
• Recommended application temperature: +5°C to +40°C (ideal: 15°C to 25°C).
• A triangular bead application is recommended for optimal performance.
• Can be applied using manual, pneumatic, battery-powered, or pump-operated dispensing equipment.
• Tooling and finishing should be completed before skin formation begins.

Why Choose Sikaflex®-268?

Sikaflex®-268 is a high-performance polyurethane adhesive and sealant specifically engineered for the rail industry. Its exceptional durability, weather resistance, and compliance with EN 45545 make it a trusted solution for glass bonding, structural assembly, and sealing applications.

When combined with Sika Booster or PowerCure technology, curing times can be significantly reduced, helping manufacturers and maintenance teams improve productivity while maintaining reliable, long-lasting performance.