Megaseal Pu2
Two Part Highly Flexible Polyurethane Sealant
MEGASEAL PU2 is a two-part, flexible polyurethane sealant designed for both horizontal and vertical joint applications. Offering exceptional resistance to weather, abrasion, and chemicals, MEGASEAL PU2 forms a strong, elastic seal that can accommodate ±25% joint movement. It bonds effectively to concrete, masonry, stone, and metals, often without priming. Available in both self-levelling and thixotropic paste versions, it suits a wide range of construction needs. MEGASEAL PU2 is ideal for heavy-duty environments such as parking decks, industrial floors, bridges, and facade expansion joints where flexibility and strength are critical.
Technical data:
- Color/Appearance : grey, white, beige liquid
- Movement Capability : 25%
- Temperature of Application : 5°C to 35°C
- Service Temperature : -5°C to 80°C
- Cure time : 2 mm / 24 hours
- Consumption : depends on joint size
- Packaging: : Pouring grade (4 lit kit) , Gun grade (2.5 lit kit)
How to Apply Megaseal Pu2
Megaseal PU2 is mixed on site and applied into a clean, dry joint with backer rod or bond breaker in place.
- Prepare the joint. Joint side surfaces must be dry, smooth, clean and free from dust, laitance or loose materials; use compressed air or a wire brush. New concrete or cementitious surfaces must be cured with moisture content not exceeding 4%, and edge defects repaired with MATEX repair products.
- Mask and prime. Apply masking tape to the joint sides before priming. Primer is not required on sound, clean, totally dry joints. Where needed, use Megaprime on porous and Megaprime SP on non-porous surfaces, applied thinly to both joint faces before the backer rod, and allowed to become tack free.
- Install backing. Pack the joint filler or backer rod tightly; the backer rod diameter should be at least 20% larger, but not greater than 33%, than the joint width. Use polyethylene bond breaker tape in construction or contraction joints, or where depth does not allow a backer rod.
- Mix. Homogenize Part A (base) with a low speed mixer for one minute, then slowly add Part B (hardener) while mixing. Mix at 200-300 rpm for 2-3 minutes to a homogeneous, lump-free mix, scraping the sides and keeping the blade in the material. For pouring grade, let it rest 3 minutes and knock the container sides with a wooden spatula to release air.
- Apply. Pour the mixed product from the pail directly into the joint (pouring grade), filling continuously without gaps. Allow it to settle and remove excess from the joint sides.
- Tool and remove tape. Tool the surface to a smooth finish without soapy water or other liquids, and remove the masking tape immediately after finishing, before the sealant cures.
- Clean tools. Clean tools immediately with Armosolvent. Hardened material can only be removed mechanically.
Summary of the method in the Megaseal Pu2 Technical Data Sheet. Always follow the full TDS on site.
Standards & Test Methods
| Standard | Title | Referenced for |
|---|
| ASTM C920 | Standard Specification for Elastomeric Joint Sealants | Type M, Grade P & NS |
| ASTM D412 | Standard Test Methods for Vulcanized Rubber and Thermoplastic Elastomers—Tension | Tensile strength and elongation |
| ASTM D2240 | Standard Test Method for Rubber Property—Durometer Hardness | Shore A hardness |
| ASTM C157 | Standard Test Method for Length Change of Hardened Hydraulic-Cement Mortar and Concrete | Shrinkage |
| ASTM D395 | Standard Test Methods for Rubber Property—Compression Set | Compression set |
Standards and test methods as referenced in the Megaseal Pu2 Technical Data Sheet. Values in the TDS are typical laboratory results under standard conditions.
Frequently Asked Questions
What is the pot life of Megaseal PU2?
Megaseal PU2 has a pot life of 90 minutes at 25°C. Cure time is 2 mm per 24 hours.
What joint widths can Megaseal PU2 be used for?
Megaseal PU2 accommodates ±25% movement in joints 6 to 35 mm wide. Width should be twice the depth for joints over 13 mm, and equal to depth for joints under 13 mm.
Which grades and pack sizes of Megaseal PU2 are available?
Megaseal PU2 PG (self-levelling pouring grade, for horizontal joints) comes in a 4 liter two-part kit. Megaseal PU2 GG (gun grade, for vertical joints) comes in a 2.5 liter two-part kit.
What surfaces can Megaseal PU2 be applied to?
The TDS lists concrete, masonry, aluminum, granite and marble, in uses such as car park, expansion and control joints, precast and curtain wall joints, and industrial floors with truck or forklift traffic.
What is the service temperature and shelf life of Megaseal PU2?
Service temperature is -5°C to +80°C. Shelf life is 12 months from production in unopened original packing, stored dry, away from direct sunlight, at no more than 25°C.
