Strait of Hormuz Tensions Return: Polyester Chain's Stress Response vs. Real Supply-Demand Dynamics

In July 2026, the re-blockade of the Strait of Hormuz triggered a dramatic shift in the polyester chain, from a prolonged downtrend to panic buying within days. Crude oil prices rose nearly 3% in a single week, with WTI returning to the $80 range. Polyester filament yarn prices increased consecutively on July 8 and 9, with some polyester plants issuing two price hikes in one day. While this rally was ignited by geopolitical tensions, the sustainability depends on supply-demand structures, inventory cycles, and end-user demand.

Background: How Geopolitical Shocks Transmit

On July 8, the US Central Command announced a series of strikes against Iran in response to attacks on commercial shipping. Subsequently, an Iranian naval air defense officer was killed in a US airstrike, and the Strait of Hormuz was re-closed. Unlike the earlier blockade in early 2026, a large number of oil tankers had already exited the strait before the closure, preventing an extreme short-term supply shortage. Oil prices did not spike to $100 as feared, but the emotional shock quickly rippled through the polyester chain.

The reaction was textbook: crude price volatility transmitted through PX and PTA to polyester filament within 48 hours. On July 8, the average polyester filament sales-to-production ratio surged to 361.9%, with the weekly average reaching 132.7%. Downstream weaving mills shifted from wait-and-see to concentrated stockpiling, reflecting deep memories of past raw material shortages.

Industry Impact: Supply Contraction vs. Weak Demand

The confidence behind this polyester price hike partly comes from active supply-side contraction. Current polyester filament capacity utilization stands at only 74.6%, far below last year's level. Upstream PTA and PX units are undergoing frequent maintenance, providing a floor for prices. However, downstream weaving mills face a different reality: June to July is a traditional off-season, with orders declining significantly and operating rates remaining low.

• Weaving mills are caught in a dilemma: running machines risks inventory accumulation, while idling them exposes them to future cost increases if raw material prices continue to rise.
• The volatile raw material prices in the first half of the year have already strained cash flows for many SMEs. Current restocking is more of a panic defense than a demand-driven replenishment.

This suggests that the recent sales explosion is a 'stress response' rather than a genuine demand recovery. If geopolitical tensions ease or oil prices retreat, polyester prices may face downward pressure.

Practical Advice

For Buyers - Avoid chasing the rally: Current prices already include a geopolitical premium. If the situation does not escalate, buying at the peak carries correction risk. Consider phased purchasing rather than large one-time orders. - Monitor inventory cycles: Mills with low raw material stocks can replenish to 2-3 weeks of usage, but avoid overstocking given persistent off-season weakness. - Lock in forward contracts: If geopolitical risks are expected to persist, negotiate partial forward price-lock agreements with suppliers to hedge against further increases.

For Exporters - Factor in currency and freight: Geopolitical conflicts can raise insurance premiums and shipping times. Add a 3-5% buffer for additional costs when quoting. - Proactive client communication: Inform overseas buyers about raw material cost volatility and seek price adjustment clauses in contracts to avoid bearing all margin erosion. - Diversify supply sources: Increase inquiries to other domestic polyester production regions (e.g., Fujian, Jiangsu) to reduce reliance on a single supplier area.