Sikasil® WT-485
Sikasil® WT-485 is a 2-component, high-modulus, neutral-curing structural silicone adhesive for structural bonding of insulating glass units into window frames and for back-bedding applications. Sikasil® WT-485 builds up its high mechanical strength and adhesion within a short period of time.
- Meets requirements of RAL-GZ 716/1
- Fast-curing for automated industrial processes
- Excellent adhesion to a wide variety of substrates
- Outstanding UV and weathering resistance
- Very good mechanical properties
- Good gap-filling capabilities
- Remains flexible over a wide temperature range
- Long-term durability
PRODUCT BENEFITS
- Meets requirements of RAL-GZ 716/1
- Fast-curing for automated industrial processes
- Excellent adhesion to a wide variety of substrates
- Outstanding UV and weathering resistance
- Very good mechanical properties
- Good gap-filling capabilities
- Remains flexible over a wide temperature range
- Long-term durability
Areas of Application
Sikasil® WT-485 has a wide adhesion range on many substrates such as glass, (coated) metal, wood, PVC and many other substrates. In combination with its good mechanical properties, especially the high modulus of elasticity, this makes the adhesive most suitable for structural bonding of insulating glass units into window frames and for back-bedding applications. Sikasil® WT-485 is especially designed for automated bonding of structural adhesive joints. It is further suitable for highly demanding industrial bonding and sealing applications. This product is only suitable for professional experienced users. Tests with actual substrates and conditions have to be performed ensuring adhesion and material compatibilityProduct Details
| Properties |
| ||||
| Chemical base | 2-component silicone | ||||
| Color (CQP001-1) |
mixed |
| |||
| Cure mechanism | Polycondensation | ||||
| Cure type | Neutral | ||||
| Density (uncured) |
mixed |
| |||
| Mixing ratio | A:B by volume A:B by weight | 10:1 13:1 | |||
| Viscosity (CQP029-6) |
| ||||
| Consistency | Paste | ||||
| Application temperature | ambient | 5 ─ 40 °C | |||
| Snap time (CQP554-1) | 12 minutes A, B | ||||
| Tack free time (CQP019-3) | 40 minutes A | ||||
| Shore A hardness (CQP023-1 / ISO 48-4) | 45 | ||||
| Tensile strength (CQP036-1 / ISO 527) | 2.1 MPa | ||||
| 100 % modulus (CQP036-1 / ISO 527) | 1.2 MPa | ||||
| Elongation at break (CQP036-1 / ISO 527) | 240 % | ||||
| Tear propagation resistance (CQP045-1 / ISO 34) | 7 N/mm | ||||
| Service temperature (CQP513-1) | -40 ─ 150 °C | ||||
| Shelf life |
|
| CQP = Corporate Quality Procedure | A) 23 °C / 50 % r. h. |
| B) The Snap time can increase add. 6 min. with component B at the end of shelf life | C) storage below 25 °C |
CURE MECHANISM
Sikasil® WT-485 starts to cure immediately after mixing the two components.
The speed of the reaction depends mainly on the temperature, i.e. the higher the temperature the faster the curing process. Heating above 50 °C could lead to bubble formation and is therefore not allowed.
The mixer open time, i. e. the time the material can remain in the mixer without flushing or extrusion of product, is significantly shorter than the snap time indicated above.
Application
Surface preparation
Surfaces must be clean, dry and free from grease, oil and dust. Surface treatment depends on the specific nature of the substrates and is crucial for a long lasting bond.
Application
The optimum temperature for substrate and sealant is between 15 °C and 25 °C.
Before processing Sikasil® WT-485 both components have to be mixed homogeneously and air-bubble-free in the correct ratio as indicated with an accuracy of ± 10 %. Most commercially available metering and mixing equipment are suitable. For advice on selecting and setting up a suitable pump system, contact the System Engineering Department of Sika Industry.
Consider that the B-component is moisture-sensitive and must therefore only be exposed briefly to air.
Joints must be properly dimensioned.
Basis for calculation of the necessary joint dimensions are the technical values of the adhesive and the adjacent building materials, the exposure of the building elements, their construction and size as well as external loads.
Tooling and finishing
Tooling and finishing must be carried out within the snap time of the adhesive.
When tooling freshly applied Sikasil® WT-485, press the adhesive to the joint flanks to get a good wetting of the bonding surface. No tooling agents must be used.
Removal
Uncured Sikasil® WT-485 may be re-moved from tools and equipment with Sika® Remover-208 or another suitable solvent. Once cured, the material can only be removed mechanically.
Re-usable, usually metallic, static mixer can be cleaned with Sika® Mixer Cleaner.
Hands and exposed skin have to be washed immediately using hand wipes such as Sika® Cleaner-350H cleaning towels or a suitable industrial hand cleaner and water. Do not use solvents on skin.
Overpainting
Sikasil® WT-485 cannot be overpainted.
Application limits
Recommended solution from Sika for structural glazing and window bonding are usually compatible to each other. These solutions consist of products such as Sikasil® SG, IG, WS and WT series. For specific information regarding compatibility between various Sikasil® products and other Sika products contact the Technical Department of Sika Industry.
To exclude materials influencing Sikasil® WT-485, all materials such as gaskets, setting blocks, sealants etc., in direct and indirect contact have to be approved by Sika in advance.
Where two or more different reactive sealants are used, allow the first to cure completely before applying the next one.
The above mentioned Sika process materials may only be used in structural glazing or window bonding applications after a detailed examination and written approval of the corresponding project details by Sika Industry.