Expansion Joint Sealant – BPU SEAL 2K

BPU SEAL 2K – Self-Leveling Polyurethane Expansion Joint Sealant

This two-component polyurethane joint sealant is designed to accommodate structural movement while providing durable, flexible sealing. Its cold-applied, self-leveling formulation is suitable for horizontal expansion joints exposed to mechanical stress and various environmental conditions.

Advantages

• Fast-curing, two-component formulation.
• Self-leveling consistency for easy application in horizontal joints.
• Cold-applied without the need for heating equipment.
• Maintains flexibility across a wide temperature range, from -40°C to +86°C.
• Good adhesion to compatible substrates with appropriate surface preparation.
• High elasticity and resistance to tensile stress, tearing and abrasion.
• Good resistance to various chemical exposures.
• Accommodates joint movement while maintaining a continuous seal.
• No thinning is normally required.

Applications

Suitable for sealing horizontal expansion and movement joints in:

• Building expansion joints.
• Parking garages and parking areas.
• Industrial floors and facilities.
• Loading and unloading bays.
• Terminal ramps and hangars.
• Infrastructure projects.
• Airport pavement joints, subject to project specifications.
• Sewage and drainage structures, where compatible with service conditions.

The sealant can be used on properly prepared concrete, stone, marble and other compatible construction substrates.

Surface Preparation

Joint surfaces must be clean, sound and free from dust, oil, grease, fuel residues, paraffin, formwork release agents, cement laitance, loose particles and other contaminants that could affect adhesion.

Where appropriate, clean the substrate using high-pressure water and allow it to dry completely. Repair damaged joint edges before applying the primer or sealant.

Priming

Select a compatible primer according to the substrate type and condition:

• Absorbent substrates: DF PUR Primer 1K or DF PUR Primer 2K, as appropriate.
• Hard concrete and other suitable prepared surfaces: DFC 100 Epoxy Primer, where specified.

Follow the relevant primer's application instructions and curing requirements before sealing the joint.

Mixing Instructions

Condition unopened containers at room temperature, preferably between 15°C and 25°C, for approximately 24 hours before application.

Mix the components thoroughly using a low-speed mechanical mixer at approximately 300 rpm with a suitable mixing paddle. Combine Components A and B according to the verified mixing ratio and continue mixing until a uniform consistency is achieved.

The prepared material has a pot life of approximately 30–45 minutes at 20°C and should be applied immediately after mixing.

Application Procedure

1. Prepare the joint by cleaning, repairing and priming the substrate as required. Apply masking tape along both joint edges to ensure a neat finish.
2. Insert a suitably sized polyethylene backer rod into the joint to control the sealant depth. A width-to-depth ratio of approximately 2:1 is recommended, subject to the specified joint design.
3. Pour the mixed sealant into the prepared joint, ensuring continuous contact with both opposing joint faces.
4. Prevent three-sided adhesion by ensuring the sealant does not bond to the bottom of the joint. The backer rod acts as a bond breaker and allows the sealant to accommodate movement.
5. Level and finish the surface using a suitable spatula or finishing tool. Carefully remove the masking tape before the material begins to cure.
6. Protect the applied sealant from water, rainfall, contamination and mechanical stress until sufficiently cured.

Curing time may be shorter at higher temperatures and longer in cold weather.

Safety Precautions

• Keep flammable materials and ignition sources away from the application area.
• Do not smoke during application.
• Ensure adequate ventilation, particularly in enclosed spaces.
• Wear suitable protective gloves, safety goggles and other required personal protective equipment.
• Avoid direct contact with skin and eyes.
• In case of eye contact, rinse immediately with plenty of clean water and seek medical advice.
• Consult the Safety Data Sheet (SDS) for detailed handling and safety information.
• Keep out of reach of children.
• Professional application is recommended.

Storage Conditions

Store in the original, unopened packaging in a dry environment at temperatures between 5°C and 25°C.

SHELF LIFE: 12 months under the recommended storage conditions.

Consumption

Material consumption depends on the width, depth and total length of the joint.

For accurate quantity calculations, determine the required sealant volume per linear meter based on the joint dimensions and allow for application losses.

Technical Specifications

Note: Technical values are based on laboratory conditions and may vary depending on temperature, relative humidity and application conditions.