In the third week of July 2026, the bulk textile commodity price index sent a clear signal: a new round of divergence between synthetic and natural fibers is underway. Acrylonitrile led the rally with a 5.25% weekly gain, followed by polyester POY and FDY with increases above 3%, while raw silk was the only decliner, falling 0.14%.
Raw Material Divergence: Synthetics Surge, Natural Fibers Under Pressure
According to industry public data, out of 17 monitored textile commodities, 10 rose, 1 fell, and 6 remained flat. Among the gainers, acrylonitrile jumped from 9,850 yuan/ton to 10,366.67 yuan/ton, with a year-on-year increase of 31.50%, making it the most aggressive mover. The polyester filament yarn series strengthened across the board: POY, FDY, and DTY rose 3.21%, 3.09%, and 2.22% respectively, with year-on-year gains ranging from 18% to 26%. The nylon series also performed positively, with POY, DTY, and FDY up between 1.54% and 2.94%.
In contrast, natural fibers showed weakness. Raw silk edged down 0.14% for the week and posted a year-on-year decline of 10.58%, the largest drop among all categories. Cotton yarn 21S and 32S held steady, with year-on-year gains of only about 5.5%, far below synthetic fiber levels. Although cotton lint inched up 0.65%, its year-on-year increase of 13.33% lagged behind polyester and nylon.
Supply Chain Transmission Logic Behind the Price Hikes
The sharp rise in acrylonitrile is not an isolated event. As a key feedstock for acrylic fibers and ABS resin, its price volatility is closely tied to propylene supply dynamics. Recent international oil price fluctuations combined with plant maintenance have tightened propylene supply, quickly passing cost pressures downstream. The polyester rally was largely driven by PTA, which rose 1.49% for the week with a year-on-year surge of 27.71%, forming the core cost support for polyester. Polyester staple fiber also rose 1.96%, confirming the linkage effect within the polyester chain.
For buyers, this means cost pressure on synthetic fabrics is unlikely to ease soon. POY is up 23.97% year-on-year, and FDY up 26.40%, and these increases will eventually pass through to grey fabrics and finished textiles. Although nylon's year-on-year gains are between 10% and 16%, they are accumulating steadily.
In contrast, the weakness in the raw silk market deserves attention. A year-on-year decline of 10.58% suggests weak end-demand or increased substitution effects. The high-end positioning of silk products makes them vulnerable in a consumption downgrade trend, while advances in synthetic silk-like fabrics are eroding traditional silk market share.
Market Expectations and Procurement Strategy Adjustments
Based on this week's data, synthetic raw material prices are likely to remain elevated in Q3. If acrylonitrile's strength persists, it will drive up costs for acrylic and blended fabrics; polyester, supported by PTA, has limited room for correction. For factories relying on synthetic materials, it is advisable to lock in costs through forward contracts and avoid chasing spot prices.
For natural fibers, cotton yarn prices are flat but still show year-on-year gains of over 5%. With the new cotton harvest approaching, short-term fluctuations are expected. The downward trend in raw silk is unlikely to reverse quickly; silk buyers may adopt a wait-and-see approach and use the low price window for strategic replenishment.