Product Data Sheet

Sikaflex®-291 is a versatile one-component polyurethane adhesive and sealant developed specifically for marine construction and repair applications. Designed to create durable, flexible, and vibration-resistant seals, it is widely used for interior and exterior marine sealing, light-duty bonding, and general-purpose assembly tasks.

This moisture-curing marine sealant bonds reliably to many common boat-building materials, including wood, fiberglass, metals, painted surfaces, ceramic materials, and plastics such as GRP. Its elastic formulation helps absorb movement, vibration, and thermal expansion, making it ideal for harsh marine environments exposed to water, weather, and mechanical stress.

Sikaflex®-291 offers excellent weathering and aging resistance while remaining easy to apply with smooth, non-sag performance. Once cured, it can be sanded and painted for a clean, professional finish. The product also provides good resistance to fresh water, seawater, and many common marine conditions, helping ensure long-lasting performance above and below the waterline.

Key Features

• Marine-grade polyurethane adhesive and sealant
• Flexible, vibration-resistant sealing performance
• Excellent adhesion to wood, fiberglass, metal, and painted surfaces
• Resistant to weathering, seawater, and aging
• Non-sag, easy-to-apply formulation
• Paintable and sandable after curing
• Suitable for interior and exterior marine applications
• Ideal for sealing joints, fittings, and light-duty bonding