SYLGARD 182 Silicone Elastomer
Two-part encapsulant · US · manufacturer-sourced
How long does DOWSIL (Dow) SYLGARD 182 Silicone Elastomer take to cure?
Short answer
Cast-and-demold plan
Gel, demold and full cure are separate days
- Mix the Two-part encapsulant to ratio and pour
- Wait for the demold time
- Sand or finish after full cure
This product’s stated stages Quoted at 77°F
- Working time ends8 hours
- Full cure2 weeks
Worth noticing: Working time is only 8 hours; the next stated stage, full cure, is 2 weeks.
Common mistake: Demolding early and leaving a soft, tacky casting that never fully hardens.
Project stage ladder
Demolding, handling, finishing and final use may occur at different times
For electronics potting and encapsulation, identify which stage the stated cure 14 days milestone actually unlocks. Earlier handling does not prove final cure.
Time demold and cure
Your countdown
Stated times
- Working time ends8 hours
- Full cure14 days
From DOWSIL (Dow) data sheet · checked 2026-10-25. Anything not listed isn’t stated by the manufacturer.
Manufacturer website: dow.com
Conditions & fine print
- Stated conditions: 77°F (25°C)
- Pot life and cure times shorten in warm rooms and with larger batches. Follow the current data sheet and mixing instructions.
- Region US. Formulas can differ between countries; check your container.
- Working time ends: At 25°C.
- Full cure: At 25°C. At 100°C it is 75 minutes, at 125°C 30 minutes and at 150°C 20 minutes.
- Entered from the cited manufacturer documentation. Check the current label for the exact formula and region. Report outdated information
- Actual results depend on preparation, thickness, ventilation, temperature, humidity, mixing and substrate.
Confirm this is your product
Closely named formulas, colors and regional versions can use different times. Match these details to your container before starting a countdown.
- Exact listing
- DOWSIL (Dow) SYLGARD 182 Silicone Elastomer
- Variant
- Two-part encapsulant
- Region
- US
- Listed use
- electronics potting, encapsulation
- Timed stages recorded
- tooling, full cure
- Source checked
- 2026-10-25
Documentation: Technical data sheet copy · Form 11-1251-01 B, 2018
Condition attached to the stated time: At 25°C.
About this product
A slower cousin of 184 with a longer working time, 8 hours against more than 2, and a room-temperature cure of 336 hours, which is two full weeks. Heat gets it down to 75 minutes at 100°C.
Using this specific product
DOWSIL (Dow) SYLGARD 182 Silicone Elastomer is listed here as the Two-part encapsulant version for electronics potting and encapsulation. For casting resin, the useful question is not simply whether the surface looks finished—it is whether the exact next-action milestone shown above has been reached.
Before you start
- Confirm the package says Two-part encapsulant; related versions can use different timing.
- For electronics potting and encapsulation, pay particular attention to accurate mixing, mold material, mass and room temperature.
- At 25°C. At 25°C. At 100°C it is 75 minutes, at 125°C 30 minutes and at 150°C 20 minutes.
How to check readiness
Check the casting itself for flex or tack before demolding. The data sheet lists a working time of 8 hours. Reserve full cure for demanding use, chemicals, washing, immersion or load—not merely gentle handling.
Avoid this mistake
Demold time is not necessarily full mechanical cure.
Compare with similar products
- Compare with Smooth-On EpoxAcast 690Full cure: 7 days there, 14 days here.
- Compare with TotalBoat MakerPoxy Crystal Clear Artist's Resin by Jess CrowFull cure: 5–7 days there, 14 days here.
Questions
How long does this product take to cure?
DOWSIL (Dow) states: The data sheet lists a working time of 8 hours. Conditions: At 25°C.. The data sheet lists a cure time of 336 hours. Conditions: At 25°C. At 100°C it is 75 minutes, at 125°C 30 minutes and at 150°C 20 minutes.. These are the manufacturer’s stated times, not a guarantee.
How long does Sylgard 182 take to cure at room temperature?
The sheet lists 336 hours at 25°C, which is 14 days. Heat curing takes 75 minutes at 100°C, 30 minutes at 125°C or 20 minutes at 150°C.
How long do I have to work with this product?
DOWSIL (Dow) states: The data sheet lists a working time of 8 hours. Conditions: At 25°C.. These are the manufacturer’s stated times, not a guarantee.
What affects how long this product takes to dry or cure?
Pot life and cure times shorten in warm rooms and with larger batches. Follow the current data sheet and mixing instructions. Follow the product label for your conditions.