When the application demands an adhesive or sealant that shrugs off abuse, resists picking, and holds fast through constant movement and vibration. Adheseal PU50FC delivers a high-strength, flexible bond that excels in aggressive environments, from public spaces to below-waterline marine installations. It's the choice for jobs where durability is non-negotiable.

Why this product exists

Adheseal PU50FC was formulated as an exceptionally tough, high-modulus (Shore A 45) elastomeric polyurethane. It provides robust anti-pick sealant properties for public buildings, schools, and prisons, where durability against tampering and abuse is critical. As a flexible structural adhesive, it meets the demands of construction, mechanical engineering, vehicular, and marine manufacturing, accommodating constant movement and vibration with impressive bond strength. This formulation ensures mechanical and abrasion resistance in the most demanding and aggressive environments, including suitability for below-waterline applications once cured.

The numbers that matter

  • Shore A 45 hardness: This high modulus means the sealant resists indentation and abrasion, crucial for anti-pick applications in high-traffic or vulnerable areas like schools and prisons. It also contributes to its robust performance on boat decks and in pavement joints.
  • ±25% joint movement capability: Despite its high hardness, PU50FC maintains excellent elasticity, allowing it to absorb movement and vibration without failure. This is vital for flexible structural bonds in construction elements, vehicular manufacturing, and facades, ensuring long-term integrity even under dynamic loads.
  • >700% elongation to break: This exceptional stretch capability provides a significant safety margin for accommodating unexpected joint movement or substrate shifts, far exceeding typical application requirements. It underpins the product's resilience in environments subject to thermal expansion, contraction, or structural flex.
  • 0.8 MPa modulus at 100% elongation: This value confirms the sealant's ability to resist deformation while still providing flexibility. It indicates a stiff, strong material that returns to its original shape, crucial for maintaining both structural integrity and a robust seal in demanding conditions.

What it's like to use

Prepare all surfaces to be structurally sound, dry, and free from contaminants. For impervious substrates, use the two-wipe process with a cleaner like Acetone or 100% White Spirits. Concrete must be cured for at least 28 days. Priming is recommended: use Adheseal 50A Surface Prep for non-porous materials like metals or plastics, and Everflex Supaprime for porous substrates like concrete or brick. Allow primers 30 minutes to 2 hours drying time.

Apply PU50FC between 5°C and 40°C. For sealant applications, cut the nozzle to a 45° angle and push the material firmly into the joint. For adhesive applications, cut the nozzle to a 90° angle, create a triangular bead, and compress the surfaces together to at least 2mm. Tool the joint with a moistened spatula within the 25-minute working time, before the 60-minute skin forms. Clean wet product and tools with Adheseal Xylene Solvent. Dried material requires mechanical removal, or white spirit solvent to soften it. For skin cleanup, use Adheseal Hand Wipes.

Where this product excels

  • Anti-pick sealing in public buildings and security-sensitive areas: Its high Shore A 45 hardness and abrasion resistance deter vandalism and picking in schools, prisons, and other public spaces.
  • Flexible structural bonding of construction elements: Ideal for demanding applications like XPS foam core reinforced sandwich panels, curtain walls, and facades, where a high-strength, flexible bond is required to accommodate movement and vibration.
  • Vehicular and marine manufacturing: Withstands constant movement and vibration, making it suitable for truck bodies, boats, and bonding solar panels to RV, caravan, and boat roofs. It is also proven for below-waterline applications once cured.
  • Pavement joints, car parks, and driveways: Maintains a waterproof, flexible joint with good tear and UV resistance, crucial for aggressive external environments and high-traffic areas.

How it fits in a real system

Adheseal PU50FC frequently serves as the final, robust sealant in critical concrete joint systems, particularly those exposed to water ingress or located below the water table. It is specified as the capping seal following the application of a hydrophilic primer such as Megapoxy H Epoxy Resin. This sequence ensures a fully sealed joint, where the primer addresses water migration within the concrete and PU50FC provides the durable, high-modulus, and abrasion-resistant outer barrier.

Choose this when

  • When the job demands an exceptionally tough, high-modulus sealant with anti-pick properties for public areas or security installations.
  • You need a flexible structural adhesive for construction elements, XPS panels, or facades that must accommodate constant movement and vibration.
  • The application is in vehicular or marine manufacturing, requiring a strong, durable bond suitable for demanding conditions or below-waterline exposure once cured.
  • You are sealing pavement joints, car parks, or driveways where high mechanical strength, abrasion resistance, and a waterproof, flexible joint are essential.
  • The project involves sealing concrete joints below the water table, typically as the final step after a hydrophilic primer.

Don't use this when

  • Not for: Internal swimming pool installations or areas with persistent high levels of chlorine. Use Adheseal PU25FC for general concrete expansion joints in these contexts.
  • Not for: Totally confined spaces, as the sealant requires atmospheric humidity to cure.
  • Not for: Aquariums or adhering mirrors.
  • Not for: Structural glazing applications. Refer to Adheseal's dedicated glazing sealants.
  • Not for: Untested composite panels. Adheseal recommends Hi-Flex Construction, subject to prior testing.
  • Not for: Some stone types without prior stain testing, or if discolouration on copper and brass is unacceptable.
  • Not for: Direct exposure to cleaning agents, solvents, or alcohol during curing, which may affect or discolour the sealant.
  • Not for: Application on bituminous, natural rubber, or EPDM rubber surfaces, or in conjunction with compounds that leach oils, plasticisers, or solvents.
  • Not for: Application when moisture-vapour transmission is emanating from the substrate or if air entrapment could cause bubbling.

Adheseal PU50FC has a low VOC content of 95 gm/lt, meeting European 2004/42/CE standards and aligning with "green star" environmental criteria, supporting sustainable building practices.