# Silicones

Silicon-oxygen polymers sold as sealants, rubbers, fluids and resins for buildings, electronics, solar and cars; made from silicon metal, mostly in China.

Source page: https://www.materialinsights.org/chemicals/silicones/

Pseudo-commodities · Rubbers & elastomers · No. 60

- Single chemical
- Feedstock: Minerals and salts
- about 3-3.5 Mt of siloxane a year (2025, indicative, basis: silicon metal output of 4.6 Mt (USGS MCS 2026) with roughly a third going to silicones at about 0.44 t Si per t siloxane)
- 7.5 t CO₂e per t
- HS 391000
 Pseudo-commodities · Rubbers & elastomers · Foundation · Matter

The sealant holding a glass tower's windows starts as silicon metal, and China makes about 70% of the world's siloxane.

Chart: Illustration: Silicones

##### Where it comes from

Chart: Map of where it comes from

Powdered silicon metal reacts with methyl chloride over a copper catalyst at about 280-300 C. The chlorosilanes are hydrolysed into siloxane and built into polymers.

##### Three things to know

1. Silicones stay flexible from about -50 C to over 200 C, which makes them hard to replace in seals and electronics.
2. Chinese siloxane traded at about CNY 10,700 a tonne in mid-June 2025, close to cash cost.
3. Dow is closing its Barry plant in the UK by mid-2026, part of closures costing $630-790 million.

##### The journey

1. 1 **Silicon metal**About 4.6 Mt made worldwide, 2025
2. 2 **Methyl chloride**From methanol and recycled HCl
3. 3 **Direct process**Silicon plus methyl chloride over copper
4. 4 **Siloxane (DMC)**Chlorosilanes hydrolysed with water
5. 5 **Formulations**Fluids, rubbers, sealants, resins

##### Go deeper pick a tab to open it in full

## Other sections

- [Overview](https://www.materialinsights.org/chemicals/silicones/overview/index.md)
- [Correlation](https://www.materialinsights.org/chemicals/silicones/correlation/index.md)
- [Production route](https://www.materialinsights.org/chemicals/silicones/routes/index.md)
- [Production](https://www.materialinsights.org/chemicals/silicones/production/index.md)
- [Feedstocks](https://www.materialinsights.org/chemicals/silicones/feedstocks/index.md)
- [Cycles](https://www.materialinsights.org/chemicals/silicones/cycles/index.md)
- [Trading](https://www.materialinsights.org/chemicals/silicones/trading/index.md)
- [Movement](https://www.materialinsights.org/chemicals/silicones/movement/index.md)
- [Regulation](https://www.materialinsights.org/chemicals/silicones/regulation/index.md)
- [Characteristics](https://www.materialinsights.org/chemicals/silicones/characteristics/index.md)
- [Emissions](https://www.materialinsights.org/chemicals/silicones/emissions/index.md)
- [Relationships](https://www.materialinsights.org/chemicals/silicones/links/index.md)