The Strait of Hormuz is central to Asian energy security. Several major Asian economies rely on the Middle East for more than half of their oil consumption . For petrochemicals, the immediate choke point was naphtha — a key feedstock for plastics and olefin production. Before the conflict, nearly 1.2 million barrels of naphtha transited the strait daily, meeting 60-70% of Asia's import needs .
For Chinese petrochemical producers, the initial impact was negative. In April 2026, producers supplying textile and plastics factories cut operations to their lowest seasonal level in three years as feedstock costs rose and demand weakened . Several major makers of purified terephthalic acid (PTA) — including one of the largest, Hengli Petrochemical Co. — took units offline, removing about 20% of national capacity. The industry's operating rate dropped as low as 68% .
Yet the broader dynamic favored China. The country's petrochemical sector had been dealing with severe overcapacity before the war even began. In October 2025, China's Ministry of Industry summoned petrochemical firms to address overproduction and what Beijing called "involution" — intense internal competition that erodes profit margins . The government identified 15 products at clear risk of oversupply, including polyvinyl chloride (PVC), polypropylene (PP), and polyethylene (PE) .
China had built seven massive petrochemical hubs over the previous decade, surpassing the United States as the biggest producer of ethylene and polyethylene . Its ethylene capacity reached an estimated 66 million metric tons per year in 2025, with another 32 million tons forecast to come online between 2023 and 2028 . Between 2024 and 2025, more than 10 million metric tons per year of ethylene capacity was added, and further additions of 6.3 million and 6.8 million tons were scheduled for 2026 and 2027 respectively .
That pre-existing overcapacity became a strategic asset when the Hormuz crisis hit. As the rest of Asia experienced supply disruptions in March 2026, China emerged as a major exporter, leveraging diversified logistics and land-based feedstock supply such as coal-to-olefins (CTO) production . Chinese producers had both the physical capacity to increase output and the commercial incentive to find export buyers, as domestic demand was already weak .
By mid-2026, multiple reports concluded that China had emerged as a relative winner from the Hormuz crisis. The New York Times reported that China had largely sidestepped the most severe repercussions of the conflict, avoiding the inflation surges and economic turmoil impacting many other countries . The consulting firm The Asia Group concluded that China was "the clearest strategic beneficiary" of the crisis .
In petrochemicals specifically, China's surplus capacity allowed it to fill supply gaps across Asia. The country banned oil-product exports, putting pressure on neighbors that depended on its refineries for essential fuels, while simultaneously offering to help alleviate their fuel shortages — a dynamic that simultaneously strengthened China's leverage and opened export channels for its plastics, polymers, and olefins .
S&P Global noted that the Middle East war turned 2026 from a projected year of petrochemical surplus into one of the most severe supply crises the industry has seen . For China, that meant its excess capacity — a problem the government had been struggling to solve — suddenly became a competitive advantage.
As of late June 2026, the United States had reached a deal with Iran to halt attacks, according to U.S. officials . The key variable is whether the Strait of Hormuz fully reopens and how quickly.
If the strait reopens and a peace deal holds: Middle Eastern energy flows would likely normalize, reducing the crisis-driven advantage China gained from regional disruption . However, a reopening of Hormuz might not lead China to swiftly revert to its previous oil acquisition rates from the Persian Gulf . The export channels to Southeast Asia could prove partly durable, especially where buyers shifted suppliers during the disruption, but price competition would intensify if Middle Eastern and Northeast Asian supply normalizes. China's fundamental overcapacity problem also remains — the government was already trying to address it before the crisis, and progress has been slow .
If the peace deal fails and the strait stays closed: China's position as a regional supplier would likely strengthen further, as its influence in Asia was already growing while neighboring countries faced fuel shortages . The longer the disruption lasts, the more China's relative advantage could harden into lasting market share, especially if competitors in Japan, South Korea, India, and Southeast Asia remain exposed to Middle Eastern energy flows .
The bottom line: reopening the strait would reduce China's crisis-driven margin advantage, but it would not necessarily reverse the export shift. China's petrochemical overcapacity predates the war, and the Hormuz crisis mainly accelerated a push into foreign markets that excess capacity had already made inevitable . The region's petrochemical trade flows have been reshaped — and may not snap back to their pre-2026 pattern even after peace returns.