Polyester staple fiber up 35.44% year-on-year. PTA up 59.46%. When two numbers like these sit in the same weekly price table, "rise and fall" no longer captures what is happening. The textile commodity data for week 39 of 2026 (September 28 to October 2) reveals a signal far more consequential than the headline weekly changes: the textile raw material market is undergoing a "K-shaped divergence," and the price gap between the upstream polyester chain and downstream cotton and regenerated cellulose fibers has widened to a level rarely seen in the past decade.
The Structural Fracture Behind the Numbers
Start with the weekly picture. Five textile commodities rose week-on-week, two declined, and the average change was a mere 0.07%. Polyester staple fiber led with a 0.64% gain, PTA followed at 0.46%, and raw silk, cotton yarn 32S, and cotton yarn 21S each edged up 0.14% to 0.20%. On the downside, acrylonitrile fell 0.46% and cotton slipped 0.07%. On its own, the week looks calm.
The year-on-year dimension tells a completely different story. Polyester staple fiber is up 35.44% YoY, PTA up 59.46%, and the three major polyester filament categories — POY, FDY, and DTY — are up 36.19%, 37.36%, and 31.11% respectively. Nylon POY has gained 38.88% YoY, and acrylonitrile is up 35.07%. This means the raw material costs across the polyester and polyamide chains have undergone a systematic elevation over the past year.
Meanwhile, cotton yarn 32S is up only 5.52% YoY, cotton yarn 21S up 6.04%, rayon yarn up 6.97%, viscose staple fiber up 11.13%, and raw silk has actually fallen 4.65%. The cotton and regenerated cellulose fiber segments have been left far behind the polyester chain.
Why Upstream-Downstream Transmission Has Broken Down
The root of this divergence lies not in the textile segment itself but in the differing cost transmission paths from upstream energy and chemicals. PTA and polyester staple fiber prices are highly elastic to crude oil and PX (paraxylene) movements. When the crude oil price center shifts upward, the polyester chain quickly passes cost pressure downstream. Cotton prices, by contrast, are shaped by planting area, weather, and reserve policies — their correlation with oil prices is far weaker than that of polyester.
For downstream factories, this means procurement strategies need recalibration. Spinning and filling enterprises that rely primarily on polyester staple fiber face sustained cost compression — a 35% YoY raw material increase is difficult to fully pass downstream through yarn price hikes. Cotton spinners, while facing milder raw material pressure, must contend with the risk of terminal orders being diverted to polyester substitutes.
Raw silk deserves separate attention. It rose just 0.20% week-on-week but fell 4.65% YoY, standing conspicuously isolated amid broad YoY gains across textile raw materials. Weak silk end-consumer demand, combined with exchange rate and tariff disruptions in export markets, has made raw silk the only textile raw material with negative YoY growth this week.
Practical Implications for Procurement and Export
Looking at industrial belt reactions, polyester plants in the Jiangsu-Zhejiang region have maintained high operating rates recently, but profit margins in downstream texturing and weaving have been visibly squeezed. Some small and medium-sized weavers have begun adjusting blend ratios, increasing cotton or viscose content to reduce dependence on polyester filament. If this substitution behavior persists, it could provide marginal support for cotton yarn and viscose staple fiber demand in Q4.
The export side is more directly affected. PTA's 59.46% YoY gain means export fabric quotes using polyester as a raw material face rigid upward pressure. Whether overseas buyers accept price increases depends on the pace of terminal retail recovery. If European and American orders fail to grow in tandem, intermediary traders will be forced to absorb part of the spread, further narrowing margins.