SikaForce®-420 L20
Non sagging assembly adhesive
SikaForce®-420 L20 is a high viscous 2-component polyurethane adhesive for assembling sandwich panels and similar constructions of various materials. SikaForce®-420 L20 is tested according to FTP Code system and approved according to the IMO Marine Equipment Directives.
- Non sagging
- IMO approved
- Good gap filling properties
- Solvent free
PRODUCT BENEFITS
- Non sagging
- IMO approved
- Good gap filling properties
- Solvent free
Areas of Application
SikaForce®-420 L20 is used primarily for assembling of profiles and sandwich constructions of e.g. glass fiber reinforced plastic, wood, metal, ceramic materials and pre-treated plastic materials. 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 : 25 100 : 19 | |||
Viscosity (CQP029-4) | Rheometer, PP25, shear rate 10 s-1, d=1 mm mixed |
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Application temperature | 15 – 30 °C | ||||
Pot-life (CQP536-3) | 20 minutes A | ||||
Open time (CQP526-3) | 30 minutes A | ||||
Press time (CQP590-4) | 1 MPa | 60 minutes A | |||
Shore D hardness (CQP023-1 / ISO 48-4) | 77 B | ||||
Tensile strength (CQP543-1 / ISO 527) | 16 MPa B | ||||
Elongation at break (CQP543-1 / ISO 527) | 15 % B | ||||
Tensile lap-shear strength (CQP546-1 / ISO 4587) | 11 MPa B | ||||
Shelf life |
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CQP = Corporate Quality Procedure | A) 23 °C / 50 % r.h. | B) 12 weeks at 23 °C / 50 % r.h. |
CURE MECHANISM
The curing of SikaForce®-420 L20 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.
Application
Volume and positioning of the adhesive must be defined in a way, that the intended gap is sufficiently filled after joining the parts. The specific applied quantity and position must be determined by tests.
The procedure for manual application is as follows: Ensure that the A-component is stirred thoroughly to avoid any sediment or separation, taking care not to stir too vigorously as this may introduce air into the product. Add the B-component in the specified ratio and stir thoroughly, ensuring a homogeneous mixture is achieved.
Apply before reaching half of the pot-life and join parts together within the open time. Consider that, if mixed in larger amounts, the exothermic reaction can reduce the pot-life and open time significantly.
For automated applications, 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®-420 L20 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®-420 L20 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.
The lowest allowed temperature during transportation is -20 °C for max. 7 days.