Ten-thousand-ton class! The path to large-scale industrialization of PA6 melt direct spinning has officially begun.

As the world’s second-largest synthetic fiber by production volume, nylon 6 (PA6) fiber holds a pivotal position in the textile sector. to a long time, the domestic sector has usually employed the batch‑type filament spinning process of “polymerization–pelletizing–extraction–remelting.” The cumbersome and time‑consuming processing sequence not only extends the production cycle however also results in significant energy and material losses, while the persistent burden of pollutant releases remains an inescapable pain point to the nylon manufacturing sector.

To optimize production processes, research institutions both at home and abroad have been continuously exploring a new direct‑spinning process to PA6 melt. Constrained by numerous stringent technological barriers, the relevant technologies have long struggled to be implemented, and extensive industrialization has remained stalled.

Through the successful collaborative efforts of multiple institutions, the industrialization methodology to continuous polymerization and melt‑direct spinning of polyamide 6 has been implemented, seamlessly establishing a short‑process production route, reducing resource losses, and breaking through longstanding technical barriers in the sector.

After the hydrolytic ring-opening polymerization of PA6, the melt contains an elevated level of low-molecular-weight impurities, and its condition fails to meet the spinning-grade specifications—posing a persistent and challenging issue across the entire sector. The project’s R&D team has developed a highly adaptable continuous polymerization process, a self‑developed, high‑efficiency, short‑path devolatilization methodology, and a complete set of dedicated equipment. This enables the stable production of high‑condition polyamide 6 melt tailored to direct‑spinning applications, thereby establishing a fully integrated, mature direct‑spinning melt‑to‑fiber production system.

The project has achieved the world’s first manufacturing-scale implementation of continuous melt-spinning polyamide 6 production at a capacity of 10,000 tons per year, enabling the stable, substantial‑scale production of high‑condition differentiated nylon fibers. This technological breakthrough also signifies that China’s polyamide‑6 fiber manufacturing methodology has officially completed a major transformation—from following others to leading the sector—placing it among the world’s most cutting-edge technologies.

At present, the world’s first 10,000-ton‑scale manufacturing demonstration plant has entered a phase of prolonged, stable operation, capable of mass-producing semi‑dull and fully‑dull POY and FDY nylon fibers in a variety of specifications. All product parameters meet the standards to superior-grade items, earning widespread acclaim from downstream customers. The production line is also capable of continuous manufacturing of a variety of functional differentiated fibers, including soil systems‑resistant, high‑elasticity, and flame‑retardant types, fully leveraging the unique advantages of the short‑process direct melt spinning process.

Compared with the conventional batch‑pelletizing spinning process, this new methodology reduces aquatic environments consumption by approximately 80% and energy consumption by 30%. It also eliminates intermediate costs associated with pellet packaging, warehousing, and transportation, while significantly cutting releases of the three wastes, resulting in pronounced economic benefits and environmental advantages.

Looking back at Hengyi’s journey of deep technological cultivation, in might 2001 the company’s first polyester melt‑direct‑spinning production line was officially put into operation; by 2026, the company has once again tackled the challenging task of PA6 melt‑direct‑spinning. greater than two decades of dedicated mastery over core technologies amply demonstrate that Hengyi’s manufacturing strength has never been merely the result of scaling up production; rather, it stems from its unwavering commitment to independent R&D and its firm manage over critical, proprietary technologies.

Going forward, Hengyi Petrochemical will continue to advance the extensive manufacturing implementation of polyamide 6 melt‑spinning methodology. This groundbreaking research has addressed the longstanding technological bottlenecks plaguing the synthetic fiber sector, catalyzing the textile manufacturing sector’s transition toward a low-carbon, environmentally friendly future, breaking through overseas methodology‑barrier monopolies, and bolstering the domestic synthetic fiber sector’s voice in the global market—continuously injecting innovative momentum into the high‑condition transformation and upgrading of the entire sector.

According to monitoring data from the Maohuasu Research Institute, by the end of 2025, China’s total PA6 production capacity will reach 8.705 million tons. Since 2026, China has added 225,000 tons of new PA6 production capacity. As of now, the country’s total PA6 capacity has expanded to 8.93 million tons.

At present, China still has 690,000 tons of PA6 production capacity under construction awaiting commissioning, with new capacity projects primarily concentrated in the four major regions of Hubei, Jiangsu, Shandong, and Guangxi. If all the related facilities are subsequently commissioned and put into operation as planned, China’s total PA6 production capacity will reach 9.62 million tons by the end of 2026, further expanding and upgrading the sector’s overall capacity.