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For expansion joints, precast panels, and structural connections requiring reliable elastomeric movement, PU25 Polyurethane Adhesive provides a highly flexible seal that accommodates up to 25% joint movement. Tested to AS/NZS 4020 for potable water contact and AS1530.3 for low ignitability, this medium-modulus sealant is suitable for sealing and adhering in interior, exterior, and below-waterline applications once cured.
PU25 Polyurethane Adhesive cures via reaction with atmospheric moisture to form a tough, permanently elastic, and dustproof joint seal. With a Shore A hardness of 25 after 14 days and a low modulus of elongation (0.4 MPa @ 100%), it absorbs joint stress across materials with differing thermal exposure coefficients without tearing or losing adhesion. The formulation incorporates biological resistance that inhibits mould and mildew growth in hot and humid environments, and it has passed accelerated UV and weathering exposure testing beyond ASTM C793-05 and ISO 11431 without chalking, cracking, or yellowing.
Suitable for perimeter sealing, connection joints, and structural bonding on these substrates:
To allow correct movement, design joints to a 2:1 width-to-depth ratio. Internal joints must have a minimum width and depth of 5mm. External joints must be a minimum of 10mm wide. The maximum joint width is 30mm, and the maximum depth is 15mm. Use a closed-cell backing rod 25% larger than the joint width to control depth and prevent three-sided adhesion.
Apply when substrate and air temperatures are between 5°C and 40°C. Concrete must be cured for a minimum of 28 days prior to application. Clean non-porous surfaces using a two-wipe process with Acetone or 100% White Spirits.
Adheseal PU25FC is a polyurethane sealant and adhesive for movement and connection joints. It is commonly used for perimeter sealing of windows, expansion joints in precast panels, and general construction or manufacturing where flexibility and strong adhesion are required.
Yes, once cured, Adheseal PU25FC is suitable for contact with potable water. It has been tested to AS/NZS 4020, confirming its safety for water intended for human consumption.
Adheseal PU25FC has a joint movement capability of ±25%. This high elasticity allows it to accommodate significant expansion and contraction without cracking or losing adhesion, as tested to ASTM C 719.
No, Adheseal PU25FC is not suitable for aquariums. It is also not recommended for internal swimming pool installations due to potential exposure to high levels of chlorine.
| Application | Key benefit | Primary trades |
|---|---|---|
| Perimeter sealing of windows and curtain walls | Forms a permanently elastic and dustproof seal with ±25% movement capability, resisting weathering and UV exposure. | Glaziers, Builders, Facade Installers |
| Expansion joints in precast/tilt-up panels, pavement, car parks, driveways | Accommodates significant structural movement while maintaining a waterproof, flexible joint, with proven long-term durability. | Concreters, Builders, Civil Contractors |
| Metal cladding and bolted lap joints | Provides excellent adhesion to most metals (including galvanised and powder-coated) and is non-corrosive, ensuring a robust and lasting bond. | Cladders, Sheet Metal Workers, Builders |
| Vehicular and marine manufacturing | Offers strong adhesion, high flexibility, and is suitable for below-waterline applications once cured, making it resistant to harsh conditions. | Marine Fabricators, Vehicle Manufacturers |
| General construction sealing and adhering | Fast curing (3mm/day), paintable, low ignitability (AS1530.3), and suitable for potable water contact (AS/NZS 4020) providing versatility and compliance. | Builders, Plumbers, Tilers, General Trades |
Correct joint design is critical for performance. Ensure all surfaces are sound, clean, dry, and free of all contaminants. Concrete must be cured for 28 days.
Maintain a 2:1 width-to-depth ratio. For external joints, minimum width should be 12mm. For internal, 5mm. Use masking tape for neat joint lines.
Insert Adhefoam open cell backer rod, sized 25% larger than the joint width, to control the sealant depth and critically, to prevent 3-sided adhesion.
For optimal, long-term adhesion and in all critical applications, priming is mandatory.
Apply one coat of Everflex Supaprime to concrete, render, brick, or timber.
After cleaning and abrading, apply Adheseal 50A Surface Prep to aluminium, powder coat, or PVC.
Apply sealant at temperatures between +5°C and +35°C. Cut nozzle at a 45° angle to the desired bead size.
Hold the gun at a 45° angle and push the sealant ahead of the nozzle. This ensures the sealant is forced firmly into the joint and prevents air entrapment, which can cause bubbles.
Tool the sealant with a moistened spatula to create a smooth, concave finish. This ensures good contact with the joint sides for maximum adhesion.
DANGER
May cause an allergic skin reaction. May cause allergy or asthma symptoms or breathing difficulties if inhaled.
Wear protective clothing, gloves (Nitrile Rubber recommended for intermittent contact), apron, and safety glasses. If inhalation risk exists, wear an organic vapour/particulate respirator meeting AS/NZS 1715 and AS/NZS 1716 requirements.
Ensure adequate ventilation to maintain air concentrations below exposure standards. Use only in well-ventilated areas. Avoid generating and inhaling dusts.
Store in dry and cool conditions between 10ºC and 35ºC. Shelf life is 12 months in original packaging. Dispose of contents/container in accordance with local, regional, national, and international regulations, preferably in an incinerator for hazardous waste.
Proper surface preparation and correct primer selection are critical for achieving optimal adhesion and long-term joint performance with Adheseal PU25FC.
Examples include concrete, aerated concrete, cement-based renders, mortars, and bricks.
Surface prep: Surfaces must be structurally sound, dry, and free of dust, loose material, oils, and other contaminants. Concrete needs at least 28 days to cure.
Primer: Required. Prime surfaces using Everflex Supaprime, applied by brush. Allow a minimum of 30 minutes and a maximum of 2 hours for solvent evaporation before applying the sealant.
Examples include aluminium, stainless steel, galvanised surfaces, powder-coated metals, PVC, and glazed tiles.
Surface prep: Slightly roughen the surface with a fine abrasive pad. Ensure surfaces are clean and free of oils, grease, and other contaminants. For impervious substrates, use the two-wipe process with Acetone or 100% White Spirits, changing cloths frequently.
Primer: Optional, but recommended for optimal long-term adhesion. Pre-treat using Adheseal 50A surface prep applied with a clean cloth. Allow a minimum of 30 minutes and a maximum of 2 hours for solvent evaporation before applying the sealant. An adhesion test is advised for metals like copper, brass, titanium-zinc, and plastics such as PVC.
| Property | Value |
|---|---|
| Product Type | Polyurethane |
| Curing System | Moisture |
| Cure Time Rate | 3 mm / 24 Hours |
| Density (Black) | 1.15 g/cm3 |
| Density (Others) | 1.16 ± 0.02 g/cm3 |
| Shore A Hardness | 25 (after 14 days) |
| Joint Movement Capability | ± 25% |
| Tear Strength (ISO 34) | 6.5 N/mm |
| Elongation to Break (ISO 8339) | > 400% |
| Modulus Elongation (ISO 8339) | 0.4 MPa @ 100% |
| Application Temperature | +5°C to +35°C |
| Service Temperature | -40ºC to +80ºC |
| Working Time | 25 min @ 23ºC & 50% RH |
| Skinning Time | 60 min @ 23ºC & 50% RH |
| VOC (ISOLEMFI 50134C Mono) | < 1.5 g/l |
| VOC (European 2004/42/CE) | 95 g/l |
| Shelf Life | 12 months in original packaging |
| Storage Temperature | Cool Dry between 10ºC and 35ºC |
| UV Resistance (500h) | Good |
| Chemical Resistance | Excellent for water, detergent solutions, moderately diluted acids & alkalis, petrol & oil for short periods |
| Sealant Classification (ISO 11600) | Type F Class 25 LM |
| Accelerated Testing UV & Weathering | No chalking, no cracks or yellowing (beyond ASTM C793-05, ISO11431 & ISO EN 14187-8) |
| AS1530.3 Test Report 23-000124 AWTA | Ignitability Index 0, Spread of Flame Index 0, Heat Evolved Index 0, Smoke Developed Index 0-1 |
| Colors | Black, White, Concrete Grey |
| Packaging | 600ml Foil Sausage, 310ml Cartridge |
Here are some common examples on where Adheseal PU25 Polyurethane Adhesive used by our customers.
