SikaForce®-646 L2F
Foaming 2-component adhesive for panel bonding
SikaForce®-646 L2F is a fast curing, foaming 2-component polyurethane adhesive for bonding sandwich panels and similar constructions of various materials.
- Suitable for bead and spray application
- Low calorific value
- Low viscosity
- Foaming
PRODUCT BENEFITS
- Suitable for bead and spray application
- Low calorific value
- Low viscosity
- Foaming
Areas of Application
SikaForce®-646 L2F is used for bonding sandwich panels with A2 classification according to EN14509. The product is only suited for use on continuous production lines. This product is suitable for experienced professional users only. Tests with actual substrates and conditions have to be performed, ensuring adhesion and material compatibility.Product Details
Properties |
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Chemical base |
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Color (CQP001-1) |
mixed |
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Cure mechanism | Polyaddition | ||||
Density (uncured) |
mixed (calculated) |
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Solid content |
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Mixing ratio | by volume by weight | 100 : 42 100 : 35 | |||
Viscosity (CQP029-4) | Rheometer, PP25, shear rate 10 s-1, d=1 mm mixed (calculated) |
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Application temperature | 15 – 30 °C | ||||
Pot-life (CQP536-3) | 2 minutes A | ||||
Open time (CQP590-3) | 4 minutes A | ||||
Curing time (CQP590-3) | 8 minutes A | ||||
Gross calorific potential (EN ISO 1716) | 18.5 MJ/kg | ||||
Shelf life |
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CQP = Corporate Quality Procedure | A) 23 °C |
CURE MECHANISM
The curing of SikaForce®-646 L2F takes place by a chemical reaction of the two components. Higher temperatures speed up the curing process and lower slow it down.
CHEMICAL RESISTANCE
In case of chemical or thermal exposure, conduct project related testing.
Application
Surface preparation
Surfaces must be clean, dry and free from grease, oil, dust and contaminants. After the cleaning process, a physical or chemical pre-treatment might be required, depending on surface and type of material. The type of pre-treatment must be determined by tests.
During the curing process, carbon dioxide is released from the adhesive. If none of the substrates are porous, measures need to be taken to allow the carbon dioxide to escape.
Application
Typically a coat weight between 100 g/m2 and 250 g/m2 is applied, depending on the substrates to be bonded. The coat weight for a given substrate combination must be determined by tests. For A2 classified panels, the maximum coat weight must be determined by calculation according to EN14509.
For advice on selecting and setting up a suitable pump system, contact the System Engineering Department of Sika Industry.
Pressing
An adequate bonding pressure is necessary to obtain a voidless contact between the substrates and the adhesive. The specific pressure is, however, dependent on the core material and must be determined by tests. The pressure must always be below the maximum compressive strength of the core. After starting the press process, do not release the pressure until the press time has elapsed.
Removal
Uncured SikaForce®-646 L2F may be removed from tools and equipment with SikaForce®-096 Cleaner. Once cured, the material can only be removed mechanically.
Hands and exposed skin have to be washed immediately using hand wipes such as Sika® Cleaner-350H or a suitable industrial hand cleaner and water.
Do not use solvents on skin.
STORAGE CONDITIONS
SikaForce®-646 L2F has to be kept between 10 °C and 30 °C in a dry place. Do not expose it to direct sunlight or frost. After opening of the packaging, the content has to be protected against humidity.