Soudaflex 40FC PU Sealant

Soudal Soudaflex 40FC High-Modulus Polyurethane Sealant & Adhesive

Soudal Soudaflex 40FC is a professional, single-component polyurethane construction sealant and adhesive developed for demanding bonding and sealing applications in the building, manufacturing and industrial sectors. Its high-modulus formulation provides strong mechanical performance, excellent adhesion to many common construction materials and permanent elasticity after curing.

Particularly suitable for concrete and metal applications, Soudaflex 40FC is used for sealing concrete floor joints, bonding roof tiles and creating strong elastic bonds in structures exposed to vibration and movement. Its polyurethane formulation also provides good resistance to UV exposure and many chemicals.

Available in 310ml cartridges and 600ml foil packs, Soudaflex 40FC is supplied in a range of colours to suit different construction and industrial applications.

Key Features and Benefits

• High-modulus polyurethane: Designed for applications requiring strong mechanical performance.
• Sealant and adhesive: Suitable for both joint sealing and elastic bonding.
• Permanently elastic: Remains flexible after curing.
• High bond strength: Provides excellent adhesion to many common construction materials.
• Concrete applications: Particularly suitable for concrete floor joints and construction sealing.
• Vibration-resistant bonding: Designed for strong elastic bonding in structures subject to vibration.
• Movement accommodation: Maximum permitted joint movement of ±20%.
• Good UV resistance: Suitable for many internal and external applications, subject to exposure conditions.
• Chemical resistance: Excellent resistance to many chemicals.
• Natural stone: Non-staining when used in accordance with the manufacturer's instructions.
• Paintable: Can be overpainted, subject to a compatibility test.
• Fast curing: Typical curing speed of approximately 3mm per 24 hours.
• Professional packaging: Available in 310ml cartridges and 600ml foil packs.

Suitable Applications

• Concrete floor joint sealing.
• Concrete wall and construction joint sealing.
• Shrinking joints in concrete floors.
• Expansion and connection joints within the specified movement limits.
• Elastic bonding in structures subject to vibration.
• Structural bonding applications in the construction industry.
• Bonding roof tiles.
• Metal bonding and sealing applications.
• Industrial manufacturing and assembly.
• General construction bonding and sealing.
• Industrial maintenance and repair applications.

Suitable Substrates

Soudaflex 40FC offers very good adhesion to many common building materials, including suitable:

• Concrete.
• Masonry.
• Metals.
• Steel.
• Aluminium.
• Polyester materials.
• Other suitable construction substrates.

Substrates must be rigid, clean, dry and free from dust and grease. Always carry out a preliminary adhesion and compatibility test on the actual materials before application.

Technical Information

Joint Dimensions

Correct joint dimensions are essential for sealant performance. Use an appropriate backing material where necessary to control sealant depth and prevent three-sided adhesion.

Substrate Preparation and Priming

For reliable adhesion, surfaces must be rigid, clean, dry and free from dust, grease and other contaminants.

• Porous substrates: Prime with Soudal Primer 100 where required.
• Non-porous substrates: Prepare using Soudal Surface Cleaner or the appropriate Soudal activator where required.
• Compatibility: Carry out preliminary adhesion and compatibility tests on the actual substrate.
• Existing coatings: Remove loose or unsuitable coatings and ensure the remaining surface is sound.

Application Instructions

• Apply using a suitable manual, pneumatic or battery-operated caulking gun.
• Ensure the joint is correctly prepared and dimensioned.
• Extrude the sealant evenly into the joint, avoiding trapped air.
• Finish with Soudal Finishing Solution before skin formation.
• Clean uncured material immediately using white spirit or Soudal Surface Cleaner.
• Allow the sealant to cure through exposure to atmospheric moisture.
• Repairs can be carried out using the same material, following the manufacturer's instructions.

Painting and Finishing

Soudaflex 40FC can be overpainted. However, because paint and varnish formulations vary, Soudal recommends carrying out a compatibility test before application. Some oxidative-drying paints may experience drying disturbances. The flexibility of the cured sealant should also be considered when selecting a paint finish.

Important Limitations

• Not suitable for polyethylene (PE), polypropylene (PP) or PTFE surfaces.
• Not suitable for bituminous substrates.
• Avoid contact with bitumen, tar and plasticiser-releasing materials such as EPDM, neoprene and butyl, as these may cause discolouration and loss of adhesion.
• Not suitable for use as a glazing sealant.
• Do not apply or allow to cure in the presence of uncured silicone sealants, alcohol or other solvent cleaners.
• Good UV resistance does not mean that colour will remain unchanged under all exposure conditions.
• Keep the area well ventilated during application and curing.

Storage and Shelf Life

The manufacturer states a shelf life of 12 months in unopened packaging when stored in a cool, dry place between +5°C and +25°C.

Frequently Asked Questions

1. What is Soudaflex 40FC used for?

Soudaflex 40FC is a polyurethane sealant and adhesive used for construction and industrial bonding and sealing. Typical applications include concrete floor joints, bonding roof tiles and elastic bonding in structures subject to vibration.

2. Is Soudaflex 40FC high or low modulus?

Soudaflex 40FC is a high-modulus polyurethane sealant and adhesive. It is designed for applications requiring strong mechanical performance and adhesion.

3. How much movement can Soudaflex 40FC accommodate?

The current manufacturer's technical data sheet specifies a maximum permitted joint movement of ±20%.

4. Can Soudaflex 40FC be used on concrete floors?

Yes. It is specifically identified by Soudal for sealing shrinking joints in concrete floors and other suitable concrete construction joints.

5. Does Soudaflex 40FC need a primer?

Porous surfaces should be primed with Soudal Primer 100. Non-porous surfaces may require preparation with Soudal Surface Cleaner or an appropriate activator, depending on the material.

6. Can Soudaflex 40FC be painted?

Yes. It can be overpainted, but a compatibility test is recommended because different paint and varnish formulations may react differently with the cured sealant.

7. How quickly does Soudaflex 40FC cure?

The manufacturer's technical data sheet gives a skin formation time of approximately 25 minutes and a curing speed of approximately 3mm per 24 hours. Actual times depend on temperature, humidity and substrate conditions.

8. Can Soudaflex 40FC be used on EPDM?

Contact with EPDM should be avoided. The manufacturer warns that plasticiser-releasing materials such as EPDM, neoprene and butyl can cause discolouration and loss of adhesion.

Technical Downloads

Refer to the latest manufacturer's technical documentation and safety information before application.

Supplied by Clever Shield Coatings UK

Clever Shield supplies Soudal construction sealants, polyurethane adhesives and specialist building products to trade professionals, contractors and customers throughout the UK.

Important: Clever Shield is a product supplier and does not provide project-specific construction, structural or waterproofing design or specification. Customers must assess substrate suitability, joint dimensions and application conditions and follow the manufacturer's current technical data sheet. Where compatibility or suitability is uncertain, obtain confirmation from Soudal or a suitably qualified design professional.