The Silicone Gel 840 is a 2-component (Platinum) Poly-Addition molding silicone that cures at room temperature to a clear colorless gel. The silicones are very fluid after mixing. The silicone can take on a very faint yellowish glow over time at temperatures above 30°C, but will remain transparent.
Due to the gel shape you can still reach the measuring pins of the electronics, after which the gel (if you work carefully) closes again sufficiently against moisture.
The very good fluidity ensures good self-venting.
- Very clear
- Extremely fluid
- Gel like
- Self venting
- Suitable for potting
Technical data
- Mixing ratio: A:B = 1:1
- Processing time (pot life) at 22°C: 80 minutes
- Functional cross-linking at 20°C: after 24 hours
- Fully cured at 20°C: after 2 days
- Viscosity at 22°C: 125 cSt
- Color: clear
- Penetration: 60mm x 10 -1
- Dielectric value: 15 kV/mm
- Volume resistance: 3X10 15 Ohm.cm
- Density: 0.94 g/cm³
Note: Pot life / de-mould time is strongly dependent on temperature! At a higher temperature, the processing time and de-molding time become shorter.
Processing
The Silicone gel 840 can be easily mixed by hand or by machine. Mix the A and B components carefully and in the specified ratio (100 parts A and 100 parts B by weight). Process the mixture within the pot life and wait with demoulding until the whole has hardened completely. You can possibly speed up the curing process by placing the whole in an oven. Please note that air bubbles will have less time to escape in that case.
Extra information
The trapping of air bubbles can best be prevented by applying a vacuum to the silicone immediately after mixing. To avoid air bubbles, stir the A and B component well but slowly without engulfing air. It is best to make a “figure-8” movement.
You can color the silicone intensely or permanently with silicone dye.
The silicone can get a very weak yellowish haze at higher temperatures. However, for most potting applications this won't hurt.
Note: This is an addition silicone. These silicones can be poisoned by sulfur, nitrogen, amino compounds and metal salts. If you are not sure whether the products you use (including gloves, spatulas and cups) contain these ingredients, do a small test first. These substances are found in many latex gloves, some plastilines, lacquers and adhesives, condensation silicones, 1-component silicone sealants, natural rubbers and 3D printing material (especially stereolithography). If you still want to use this, you will have to put on a protective layer of poly vinyl alcohol.
shelf life
Provided that the silicone is stored in closed packaging, cool and frost-free, the shelf life is at least one year.
Safety requirements
If you frequently work with the silicone, it is recommended to wear gloves during processing and to ventilate the area well. For safety instructions, please refer to the safety data sheet.
Further important safety information
H-Code hazard statements
H315 - Causes skin irritation
H319 - Causes serious eye irritation
H361f - Suspected of damaging fertility
H226 - Flammable liquid and vapour
P-Code Precautions
P201 - Obtain special instructions before use
P202 - Do not handle until all safety precautions have been read and understood
P210 - Keep away from heat/sparks/open flames/hot surfaces. - Do not smoke
P281 - Use personal protective equipment as necessary
P308 + P313 - IF exposed or concerned: Get medical advice/attention
P370 + P378 - In case of fire: Use dry soda ash to extinguish
Documentation
information sheet Silicone Addition Gel 840 Clear
EN - Safety data sheet Silicone addition Gel 840 Clear A component.pdf
EN - Safety data sheet Silicone addition Gel 840 Clear B component.pdf
