Nextstar 120 Structural Polyurethane Foam
Nextstar 120 Structural Reinforcement Polyurethane is the strongest injection polyurethane Structural Foams on the market. When repairing cracks with carbon fiber staples or Stitches # 120 can be injected in the crack instead of epoxy. When compared to using epoxy, the installer will use about one-third the amount of material, therefore, saving time and material costs. Only use #120 in structural repairs when used with carbon fiber to support repairs in tension. Nextstar 120 is a unique two-part hydrophobic in that it does not need any moisture to expand, therefore it is widely used in pipe penetration and dry crack repair.
- Expands two to six times its original volume.
- Used to repair cracks in conjunction with carbon fiber staples
- Packaged in Dual 22oz./300ml 1:1 dual-tube sets.
- Use with 3/8 X 24 static mixer Air-powered injection tool recommended
- 1 Nut and static mixer tube provided with each tube set.
120 Structural Foam |
NextStar 120 Structural Poly Foam |
Mixture Ratio 1:1 |
Technical Specifications |
Density (Core-Free Rise ASTM D-1622 12Lbs |
Low Temperature ASTM D-2126 |
Aging ( 20°F) (Shrinkage) <0% 1Day |
(Shrinkage) <0% 7Days |
Water Absorption None |
Shear Strength ASTM C-273 75 Psi |
Tensile Strength ASTM D-1623 300Psi |
Elongation ASTM D-1623 5% |
Viscosity 375 CPS |
% Solid 100 |
TDI Content 0% |
USDOT Shipping Data Unregulated Class 55
|
Packaged in Dual 300ML Tubes supplied with nut and Static Mixer.
Contractors with special pricing must Purchase retaining nut and static mixers separately.
Structural foam is used in situations where large voids are subject to some movement and as a result, a solid non-compressible product must be injected in the concrete void to stop compression forces from allowing the wall, floor, or concrete structure from moving. Structural foam is also commonly used to fill pipes and large voids in concrete. Generally, Epoxy is recommended as it has high strength and cannot be compressed with a good bond to the concrete itself. Epoxy, however, is the highest cost method and for some smaller structural cracks is the best option and reasonable given its advantages.
The 120 Structural Polyurethane foam is best used for wall cracks over ½ in or 1.5 cm when it is calculated that large volumes of epoxy would be needed and the cost of the repair at that point may not be feasible. The structural foam allows to reduce the volume needed by six times and will stop wall compression, however, does not have any tensile strength and this is the reason that carbon fiber straps, stitches, staples or fabric are used across the repair area to stop the area from pulling apart under load.
Using Structural 120 polyurethane foam with carbon fiber can result in a repair that is stronger than Epoxy by itself. In most cases, the repair cost of the fiber and the polyurethane would be less than Epoxy only for these types of large concrete cracks. Smaller cracks are still best repaired using Epoxy and standard polyurethane foam for leaking cracks.
Voids and pipe intrusions.
Nextstar 120 foam is excellent for filling in inside or outside pipes through walls with fast cure times this it very cost-effective.
Grouting large cracks or voids can also be accomplished with concrete-based products but suffers failure most times from poor bonding and may be crushed by the structural forces on it if the wrong type of cement grout is used. For most situations, we see this as a common method used simply because of the low cost and product availability. Should reinforcement be needed such as with carbon fiber or epoxy bonded rebar cement grout crack repair for cracks is a poor choice as it has a history of failing before other methods. Compression strength can be compromised with poor-quality aggregate added to the mixture as a fill or low ratio of cement to aggregate used. Structural grouting should only be used if enough volume is used to ensure proper strength and mixture and is the most economical and reasonable only because enough volume of material is used to sustain structural requirements. Cement Grouts however if used with carbon fiber may suffer shrinkage and affect the carbon placement or bond as the mixture cures. Common methods are to Epoxy bond re-bar into slabs or repair area before the new cement is placed to add reinforcement but may not work well with carbon fiber.
- When dispensing from the cartridge it is always best to keep the product flowing as stopping may cause the urethane to foam up and plug the mixer, and the need to replace the mixer.
- Warming the cartridge in advance may help accelerate the foaming action and if any water or moisture is present it will accelerate at a faster rate.
- Filling a large hole or void that goes through a wall can be accomplished by attaching plywood or other covers over the void anchoring to the concrete. Drill a hole in plywood only large enough for the mixer tip to enter and inject that way. Large pressures can build, and this is the reason for anchoring to the cover to the wall.
- It’s important to anticipate the amount you are injecting vs the void size. 120 polyurethane depending on temperature and moisture level can expand more than is expected. Sometimes the reaction will be delayed for up to 5 min or so. Injecting too much product will possibly cause uncontrolled expansion creating a mess and a waste of product.
- Should you be injecting into a large wall crack that extends into the bottom footing it is best to inject your first cartridge and wait approximately 5 minutes before continuing. This allows for foaming action to start and prevent drain out into the soil of the other injections.
- 120 foam cures fast enough that you can apply carbon fiber reinforcements as short as 10 minutes after injection.
- We guarantee the product in storage 1 year from purchase but can be tested by dispensing a small amount without a mixer into a disposable cup and mix with a stick by hand and if the polyurethane foams up and starts to set in at least 20 minutes it will be ok to use.
partially used tubes will not usually be usable after being stored as cross-contamination between cartridge sides is difficult to stop even when using a flow restrictor.
Links to the other Polyurethanes
NextStar 102 Dual Cartridge Polyurethane Standard use product
Koster 2N1 Dual Cartridge Polyurethane
NextStar 103 Dual Cartridge Foam For Larger Leaking Cracks
NextStar 100-800 High-Pressure Polyurethane used with Electric High-Pressure Pump or Manual Tool