Sikaflex®-591
Multifunctional sealant for marine applications
Sikaflex®-591 is a sealant based on Sika’s Silane Terminated Polymer (STP) technology. With it’s excellent resistance against the harsh maritime weathering conditions it can be used for a wide range of applications. Sikaflex®-591 exceeds common environmental and safety standards and sets a new benchmark from an ecological point of view. Sikaflex®-591 meets the low spread flame requirements (FTP Code Part 5) set out by the International Maritime Organization (IMO).
- IMO approved
- Exceeds EH&S standards
- Free of isocyanate, solvents, PVC, phthalates and tin catalysts
- Highly elastic
- Excellent weathering stability
- Very good processing and tooling characteristics
- Bonds well to a wide variety of marine substrates
PRODUCT BENEFITS
- IMO approved
- Exceeds EH&S standards
- Free of isocyanate, solvents, PVC, phthalates and tin catalysts
- Highly elastic
- Excellent weathering stability
- Very good processing and tooling characteristics
- Bonds well to a wide variety of marine substrates
Areas of Application
Sikaflex®-591 is a multipurpose sealant designed for marine applications. It is suitable for elastic, vibration-resistant joint seals and for a wide variety of interior and exterior sealing applications.Sikaflex®-591 bonds well to substrates commonly used in the marine industry. Sikaflex®-591 is not suitable for applications with teak wood and plastics that are prone to stress cracking (e.g. PMMA, PC, etc.). This product is suitable for experienced professional users only. Test with actual substrates and conditions have to be performed ensuring adhesion and material compatibility.
Product Details
| Chemical base | Silane Terminated Polymer | |
| Color (CQP001-1) | White, Black, Grey, Brown | |
| Cure mechanism | Moisture-curing | |
| Density (uncured) | 1.5 kg/l | |
| Non-sag properties | Very good | |
| Application temperature | 5 ─ 40 °C | |
| Skin time (CQP019-1) | 35 minutes A | |
| Open time (CQP526-1) | 20 minutes A | |
| Curing speed (CQP049-1) | (see diagram) | |
| Shrinkage (CQP014-1) | 1 % | |
| Shore A hardness (CQP023-1 / ISO 48-4) | 45 | |
| Tensile strength (CQP036-1 / ISO 527) | 2.2 MPa | |
| Elongation at break (CQP036-1 / ISO 527) | 500 % | |
| Tear propagation resistance (CQP045-1 / ISO 34) | 15 N/mm | |
| Service temperature (CQP513-1) | -50 ─ 80 °C | |
| Shelf life | 12 months B |
| CQP = Corporate Quality Procedure | A) 23 °C / 50 % r. h. | B) storage below 25 °C |
CURE MECHANISM
Sikaflex®-591 cures by reaction with atmospheric moisture. At low temperatures the water content of the air is generally lower and the curing reaction proceeds somewhat slower (see diagram 1).
Diagram 1: Curing speed Sikaflex®-591
CHEMICAL RESISTANCE
Sikaflex®-591 is generally resistant to fresh water, seawater, diluted acids and diluted caustic solutions; temporarily resistant to fuels, mineral oils, vegetable and animal fats and oils; not resistant to organic acids, glycolic alcohol, concentrated mineral acids and caustic solutions or solvents.
Application
METHOD OF APPLICATION
Surface preparation
Surfaces must be clean, dry and free from grease, oil and dust.
Surface treatment depends on the specific nature of the substrates and is crucial for a long lasting bond. Suggestions for surface preparation may be found on the current edition of the appropriate Sika® Pre-treatment Chart. Consider that these suggestions are based on experience and have in any case to be verified by tests on original substrates.
Application
Sikaflex®-591 can be processed between 5 °C and 40 °C but changes in reactivity and application properties have to be considered. The optimum temperature for substrate and sealant is between 15 °C and 25 °C. Sikaflex®-591 can be processed with hand, pneumatic or electric driven piston guns.
In case Sikaflex®-591 could get in contact with polyurethane ensure that those products are cured or wait at least 24 hours prior to seal.
Tooling and finishing
Tooling and finishing must be carried out within the skin time of the product. It is recommended using Sika® Tooling Agent N. Other finishing agents must be tested for suitability and compatibility prior the use.
Removal
Uncured Sikaflex®-591 can be removed from tools and equipment with Sika® Remover-208 or another suitable solvent. Once cured, the material can only be removed mechanically.
Hands and exposed skin have to be washed immediately using hand wipes such as Sika® Cleaner-350H or a suitable industrial hand cleaner and water. Do not use solvents on skin!
FAQ
You will find different variations and materials for rub rails such as GRP, paints, wood and moulded PVC, etc. Therefore a good surface preparation is key. Products needed depending on the rub rail material to be bonded.
To ensure a good final result follow the advice given in the pre-treatment chart. Common product for rub rail bonding is our assembly adhesive for marine Sikaflex®-292i or the STP based marine sealant Sikaflex®-591.
For further details read our application guidelines and our pre-treatment chart.
Winches, windlasses are subject to high mechanical stresses, fans, hatches and hatch covers to low stresses. To make sure your fittings are sealed strongly we recommend the following:
Bedding and sealing of fittings subject to high mechanical stresses
Deck fittings such as chain plates, winches and guide rollers must absorb very high dynamic stresses. For this purpose, a high-performance product, Sikaflex®-292i, our assembly adhesive, should be used in conjunction with additional mechanical fixings.
Bedding and sealing of fittings subject to minimal mechanical stresses
Deck fittings, such as ventilators and cover strips, need to be waterproofed but are not subject to high tensile or torsion stresses.
These fittings can be effectively bedded and sealed with only Sikaflex®-291i or if the joint remains visible and is exposed to weathering, then use Sikaflex®-591 or Sikaflex®-295 UV.
Check pre-treatment chart for surface preparation of substrates prior to application and follow application steps according to application guidelines.
For further details read our application guidelines and our pre-treatment chart.