Key takeaways
- Every commodity-polymer price is built from three layers — feedstock, monomer, and resin — and the layer that moved tells you whether a price change will hold or reverse.
- Feedstock: naphtha tracks crude oil, ethane tracks Henry Hub gas; when crude rises and gas doesn't, ethane-based US Gulf/GCC resin undercuts naphtha-based Asia and Europe.
- Monomer (ethylene/propylene) spikes during cracker turnarounds and resin follows 3–6 weeks later; resin price = monomer + a polymerisation spread (~$80–200/t in commodity PE).
- Diagnose the move: resin alone = demand-driven, lasts quarters; feedstock up but monomer flat = a price step is coming; monomer up but feedstock flat = a turnaround that will partly reverse.
When a buyer asks why polyethylene moved up forty dollars last week, the answer is almost never "resin demand." It is one of three upstream layers, and the layer that moved tells you whether the move will hold or whether it will reverse inside a month.
Most of the world’s polyethylene and polypropylene starts from naphtha cracking or, in North America and the Middle East, from ethane and propane cracking. Naphtha is a refinery cut, so its price tracks crude oil with a refinery margin layered on. Ethane is a natural-gas cut, so its price tracks the Henry Hub gas market.
When crude rises and gas does not, the spread between naphtha-based polyethylene (Asia, Europe) and ethane-based polyethylene (US Gulf Coast, GCC) widens. That is why North American producers usually undercut Asian producers in cost terms, and why the export volumes from those origins move opposite to the spread.
Cracking produces ethylene and propylene. Those monomers are themselves traded commodities, with their own price benchmarks (Asian Contract Price for ethylene, MOPJ for naphtha-derived monomers, Mt Belvieu for US ethane-derived). When monomer is short — because a major cracker is in turnaround — monomer prices rise faster than feedstock, and downstream resin follows three to six weeks later.
Resin is the layer the buyer actually transacts in. Resin price is monomer plus a polymerisation margin (the resin spread). When demand is strong the spread widens; when producers are competing for orders it narrows. In commodity polyethylene the spread typically runs $80–$200 per tonne. In specialty grades it can be five times that.
If feedstock is stable and monomer is stable but resin is moving, the move is demand-driven and likely to last several quarters. If feedstock is moving but monomer is stable, the change has not yet been passed through and a price step is coming. If monomer is moving but feedstock is not, somebody upstream is in turnaround and the move will partly reverse when the unit restarts.
OmniaStrata’s pricing intelligence pulls all three layers daily. We do not publish a daily price index — the public ones (ICIS, Platts, Argus) cover that better than we could — but we use them in every active negotiation to tell a buyer why an offer moved, which is more useful than telling them how much it moved.
Pricing also interacts with origin geography. The GCC region’s ethane advantage is a structural cost feature, not a market one — it is why Saudi and Qatari volumes anchor the global polyethylene cost curve.
Frequently asked
Questions on the desk
How is the price of polyethylene determined?
From three stacked layers: feedstock (naphtha or ethane), monomer (ethylene/propylene), and resin (monomer plus a polymerisation spread). The resin layer is what a buyer transacts, but feedstock and monomer drive most of the movement.
Why is US and Middle East polyethylene cheaper than Asian?
Because of feedstock. US Gulf Coast and GCC producers crack ethane (a natural-gas cut tracking Henry Hub), the cheapest commercial PE feedstock, while Asia and Europe crack naphtha (a refinery cut tracking crude). When crude is high relative to gas, the ethane-based producers undercut on cost.
What is the resin spread?
The polymerisation margin added on top of monomer cost. It widens when demand is strong and narrows when producers compete for orders — typically $80–200 per tonne in commodity polyethylene, and up to five times that in specialty grades.
Will a polymer price increase last?
It depends which layer moved. If resin moves while feedstock and monomer are stable, the move is demand-driven and likely to last quarters. If feedstock moved but monomer hasn't, a price step is still coming. If monomer moved but feedstock didn't, a cracker is in turnaround and the move will partly reverse on restart.
General market commentary from the OmniaStrata desk, provided for information only. It is not legal, financial, tax, or trading advice, and it is not an offer or a commitment to any terms. Figures such as price ranges, spreads, financing costs, and credit periods are illustrative market context, not OmniaStrata's rates or terms. Actual contract terms — including price, payment instrument, credit, insurance, and Incoterms — are agreed in writing on a per-transaction basis and at OmniaStrata's discretion. Market conditions change; figures reflect the publication date.