Propylene oxide: Overview
How a small molecule fills the world's mattresses
How a small molecule fills the world's mattresses 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.Propylene oxide (PO, C3H6O) is a volatile, flammable liquid made by oxidising propylene. Unlike ethylene oxide, it cannot be made by direct air oxidation at scale, so producers use chlorine (chlorohydrin), organic hydroperoxides that create styrene or tert-butanol co-products, or hydrogen peroxide (HPPO). About two-thirds goes into polyether polyols for polyurethane foams in mattresses, furniture, cars and insulation. China has built capacity fast, to about 9.3 Mt a year by end-2025, turning a former import market into a glut.
Volume about 12 Mt produced a year (2025, indicative: about 16 Mt capacity x about 75%) Market value about $13-14 billion a year (indicative: about 12 Mt x about $1,100/t, 2025 Asian levels) Growth about 3-4% a year, led by polyurethanes in Asia (indicative) Mysteel Jun 2025 (China capacity); Alchempro Nov 2025 (price); global totals indicativeKey uses
| Use | Share | Annual volume | Why this commodity | Alternatives |
|---|---|---|---|---|
| Polyether polyols (polyurethanes) | 65% | about 7.8 Mtbasis | PO's ring opens with glycerine or sugar starters to build long polyether chains, which react with MDI or TDI to make flexible and rigid PU foams. No other monomer gives the same mix of flexibility, cost and water resistance. indicative (basis: industry splits) | bio-polyols from castor or soy oil recycled polyols from foam glycolysis |
| Propylene glycol (MPG) | 20% | about 2.4 Mtbasis | Hydrating PO gives a low-toxicity glycol for unsaturated polyester resins, food, pharma, cosmetics, de-icing and safer antifreeze. indicative | bio-MPG from glycerine hydrogenolysis (ADM, Oleon) |
| Propylene glycol ethers | 6% | about 0.7 Mtbasis | Low-toxicity solvents for coatings, inks and cleaners, replacing ethylene glycol ethers. indicative | ethylene glycol ethers esters |
| Other: polycarbonate polyols, allyl alcohol, PO-EO surfactants, fumigation | 9% | about 1.1 Mtbasis | Smaller uses including block copolymer surfactants and 1,4-butanediol via allyl alcohol. indicative (remainder) | various |
From raw material to user
- Propylene About 0.75-0.8 t propylene per t PO (indicative).
- Oxidant Chlorine (about 1.4 t per t PO in chlorohydrin), ethylbenzene or isobutane hydroperoxide, cumene hydroperoxide, or about 0.6 t hydrogen peroxide (100% basis) in HPPO (indicative).
- Epoxidation Titanium silicalite catalysts in HPPO give over 95% selectivity with water as the only by-product (indicative).
- Polyols and glycols Polyol plants are usually built beside PO units because PO is hazardous to ship.
- Polyurethanes Polyols are combined with MDI or TDI at foam makers.
Made from (commodity table)
Oil Crude oilThree things to know
- China's PO capacity was expected to reach about 9.3 Mt/yr by end-2025 after 1.54 Mt/yr of new units from June 2025 (Mysteel).
- PO prices in Asia fell about 23% from May 2024 to June 2025, to about $1.0/kg, then recovered to about $1.13/kg in October 2025 (Alchempro).
- The old chlorohydrin route uses about 1.4 t chlorine per t PO and makes about 40 t of salty wastewater per t, which is why China is phasing it out (indicative).