YJS-640 poly addition cured rtv-2 silicone for cement mold making
Category: Concrete Casting silicone  Publish Time: 2018-08-07 10:34 
YJS-640 is a two-component 1:1 Mix addition (platinum) cured RTV silicone rubber which cures at room temperature. YJS-640 is is hard and not very flexible, with a 40A Shore hardness.
1. Description
YJS-640 is a two-component 1:1 Mix addition (platinum) cured RTV silicone rubber which cures at room temperature. YJS-640 is is hard and not very flexible, with a 40A Shore hardness. It is firm enough to hold heavy concrete parts yet still has flexibility for demold. A good option for making molds to cast concrete, urethane foam and other resins.
This silicone is recommended for repetitive production of intricate shapes cast in epoxy or urethane resins. It is also used for potting electronic components and protecting sensitive assemblies against shock and vibration.

2.Features of YJS-640 platinum cure silicone
-Amazing fluidity and easy to operate
-Platinum-based, food
-grade silicone (environmental friendly, odorless and non-toxic)
-Delicate design available
-Mixing ration: 1:1, easy to mix
-Easy de-molding
-Excellent tension and tear strength
-High performance in duplication-Shrinkage is almost zero (below 0.1)
-Excellent resistance to weather, temperature, aging, acid and aging-proofing.
-High resistance to high temperature and aging(resist -60℃ to 250℃) 

3. Technical datasheet

Typical general characteristics Inspection Method Value
Product data (Catalyzed A+B) YJS-640
Hardness Shore A 40±2
Mix Ratio A:B 1:1/10:1
Color / translucent
Pot life 25 °C (77F) 30-40
Curing time 25 °C (77F) 3-4
Mixed viscosity mPa.s 9000±1000
Tear-strength kg/cm 12±2
Tensile-strength M.pa 6.0±1.0
Elongation % 450±50
Shrinkage % 0.1

 4.Using instructions 

1. Place a plastic container on a small scale, making sure to zero out the weight on the scale. Note: use a container that, during rise under vacuum in Step 5, will allow for material to expand to 4-5 times its resting volume.
2. Pour catalyst into the plastic container, noting weight of material poured.
3. In the same container, pour an equal weight of base on top of the catalyst (e.g., 100 grams of catalyst and 100 grams base). Note: within a 5% weight variance, the end result is not altered.
4. With a clean, dry mixing spatula, mix energetically until the color of the product is homogeneous. Note: working time begins at this step. Mixing should take no longer than 1-2 minutes.
5. Place container under vacuum and vacuum until material bubbles and rises. Release vacuum and repeat until bubbles are removed. Vacuuming should take no longer than 3-4 minutes.
6. From a height of approximately 30 cm, pour the mixed silicone into the mold frame. Maintain the pouring stream in the same spot so as to minimize introduction of air bubbles into the mold.
7. Allow the mold to sit, undisturbed, for at least 4 hours to ensure the silicone is fully cured.
8. Remove the mold from the frame.
9. Cut around the pattern carefully to release it from the silicone rubber mold.

Part A: a non-toxic and odorless liquid with translucent color and platinum inside.
Part B: a non-toxic and odorless liquid with translucent color.
ATT: We can do any curing time as your requirements.

When stored at or below 32°C (89.6°F) in the original unopened containers, YJS-6 series Silicone have a usable life of 12 months.

1kg/drum; 5kg/drum;10kg/drum; 20kg/drum;25kg/drum;200kg/drum.

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QQ  Shirley Wu