SikaFlex-221 - Bonding and sealing sealant - Sika

SikaFlex-221 - Bonding and sealing sealant - Sika

Sikaflex-221 is a one-component polyurethane sealant adhesive that polymerizes under the action of atmospheric humidity to form a durable elastomer .
The performance of Sikaflex-221 has been validated for many years on in-service applications.

Features

• Single-component
• Flexible
• Faint odor
• Resistance to aging and weathering
• Non-corrosive
• Can be painted
• Can be sanded
• Good adhesion to a wide range of surfaces
• NSF approved for occasional food contact and contact with drinking water

Areas of application

Sikaflex-221 has a high bonding power on many substrates such as wood, metals, primers and paints (two-component), ceramics and plastics, for the creation of durable elastic sealing joints.

Application

1. Sikaflex-221 must be applied to dry, grease-free and dust-free surfaces.
2. Sikaflex-221 must be applied at a temperature between +5°C and +40°C.
   Optimum application temperature: +15°C to +25°C.
3. Sikaflex-221 is implemented using any application system for single-component products: manual or pneumatic guns (marketed by Sika) or pumping unit (for advice on pumping equipment consult your Sika technician).
4. The joints must be smoothed before the product has formed its skin.

Color

White, Steel Grey, Black and Brown.

Packaging

• 300 ml cartridge
• 400-pack
• 600 ml pouch

FAQ - Frequently Asked Questions

1. Is Sikaflex-221 suitable for outdoor use?
   Yes, it is resistant to weathering, humidity and climatic variations. It is perfectly suited for outdoor applications.
2. Can Sikaflex-221 be painted?
   Yes, after complete polymerization. It is recommended to perform a preliminary test to check compatibility with the paint being used.
3. Can it replace a structural adhesive?
   No, Sikaflex-221 is a versatile bonding sealant, but it is not intended for structural assemblies requiring specific mechanical performance.
4. What media does it adhere to?
   It adheres to many materials such as metal, wood, polyester, PVC and some plastics. A primer may be necessary depending on the surface.
5. How long does it take to dry?
   It forms a skin on the surface relatively quickly (depending on ambient conditions) and hardens progressively at a rate of about 3 mm per 24 hours.
6. Is it suitable for vibrations?
   Yes, it is specially designed to absorb vibrations and movements, making it ideal for vehicles and mobile structures.
7. Can it be used for a roof?
   It can be used for certain sealing work, but for specific roofing applications, it is advisable to check the manufacturer's technical recommendations.