Silicones: Overview
From skyscraper glazing to shampoo and solar panels
What this tab covers What the chemical is, how big its market is, what it is used for (with shares, volumes, why it wins and what could replace it), and its chain from raw material to end user. Ends with three things to remember.Silicones (polysiloxanes) have a silicon-oxygen backbone with methyl groups attached. They stay flexible from -50 C to over 200 C, repel water and insulate electricity, so they are hard to replace in sealants, EV and solar electronics, medical devices and cosmetics. Silicon metal reacts with methyl chloride to chlorosilanes, which are hydrolysed to siloxane (DMC) and built into polymers. World output is roughly 3-3.5 Mt of siloxane a year (2025, indicative), mostly in China. Chinese DMC fell to about CNY10,700/t in June 2025 (SMM), near cash cost, and Dow is closing its UK siloxanes plant in mid-2026.
Volume 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) Market value about $20 billion for finished silicone products (2025, indicative, industry estimates); DMC at about $1,500/t is the cheap end Growth about 4-6% a year (indicative), led by EVs, solar, electronics and construction in Asia USGS MCS 2026 via silicon tile; SMM, Jun 2025 (DMC price); volume and value indicativeKey uses
| Use | Share | Annual volume | Why this commodity | Alternatives |
|---|---|---|---|---|
| Construction (sealants, adhesives, coatings, water repellents) | 30% | about 1.0 Mtbasis | Silicone sealants bond glass and metal in curtain walls and windows and stay elastic for decades under sunlight. Structural glazing relies on them. indicative share, industry estimates | polyurethane and MS-polymer sealants acrylic sealants |
| Industrial processing and transport (gaskets, hoses, antifoams, lubricants) | 25% | about 0.8 Mtbasis | Silicone rubber parts survive engine and battery heat; silicone antifoams and release agents are used across chemicals, food, textiles and pulp. indicative share | EPDM and FKM rubbers mineral oil and polyether antifoams |
| Electrical, electronics and solar (encapsulants, thermal interface materials, insulators) | 20% | about 0.65 Mtbasis | Silicone gels and potting compounds protect power electronics, EV battery modules and LEDs; silicone sealants frame solar modules; silicone rubber high-voltage insulators resist pollution. indicative share | epoxy and polyurethane potting porcelain and glass insulators |
| Personal and household care | 15% | about 0.5 Mtbasis | Cyclosiloxanes and silicone fluids give shampoos, conditioners and skin creams a smooth, non-greasy feel. EU limits on D4, D5 and D6 are pushing reformulation. indicative share | hydrocarbon emollients plant oils isododecane |
| Healthcare and medical | 5% | about 0.16 Mtbasis | Biocompatible silicone rubber for catheters, tubing, implants and baby teats; simethicone in medicines. indicative share | polyurethane TPE latex |
| Other (paper release coatings, textiles, food contact) | 5% | about 0.16 Mtbasis | Silicone release coatings on labels and baking paper; textile softeners; bakeware. indicative share | fluorochemical and wax coatings |
From raw material to user
- Silicon metal World output about 4.6 Mt in 2025, China about 4.0 Mt (USGS MCS 2026 via silicon tile).
- Methyl chloride Made from methanol and HCl, with HCl recycled from hydrolysis; about 0.95 t methanol per t siloxane (stoichiometric with losses, indicative).
- Direct (Rochow-Müller) process Silicon powder reacts with methyl chloride over copper at about 280-300 C to methylchlorosilanes, about 80-90% dimethyldichlorosilane (indicative).
- Hydrolysis to siloxane (DMC) Dimethyldichlorosilane plus water gives cyclic siloxanes (D4, D5) and linear oligomers, traded as DMC.
- Polymers and formulations Fluids, gums for HTV rubber, liquid silicone rubber (LSR), RTV sealants, resins and silanes; sold at several times DMC price.
Made from (commodity table)
Si SiliconThree things to know
- China makes almost 80% of the world's silicon materials (USGS MCS 2026 via silicon tile) and most of its siloxane monomer, so Chinese DMC prices set the global floor.
- Chinese DMC traded at about CNY10,700/t in mid-June 2025, near cash cost, with operating rates expected near 70% (SMM).
- Dow is closing its Barry, UK basic siloxanes plant by mid-2026 as part of closures costing $630-790 million and affecting 800 jobs (ERJ, Jul 2025).