Toray Industries, Inc., announced today a breakthrough in recycling nylon 66. The company recently deployed a proprietary depolymerization technology using subcritical water (see note 1) to depolymerize this resin uniformly and efficiently in just minutes, and recover it as a raw monomer material.

Demand for nylon 66 is estimated at 100,000 metric tons annually in Japan and 1.3 million tons worldwide. Its high heat resistance and strength make it essential for automotive and industrial applications. These include automotive textiles such as airbags and tire cords, and plastic components such as radiator tanks, cylinder head covers, and oil pans. Tighter recycling regulations for automotive and other plastics in Japan have made it mandatory to collect used nylon 66-based airbags, making it a promising material for chemical recycling.

Chemical-recycled nylon 6 (note 2) for which demonstration efforts are underway, entails recovering a monomer called caprolactam. Contrastingly, the process for chemical-recycled nylon 66 requires recovering hexamethylenediamine and adipic acid monomers. Toray drew on its expertise in nylon 6 chemical-recycled technology to assess the depolymerization reaction of nylon 66 in subcritical water. It developed a proprietary technology to suppress side reactions, making it possible to efficiently recover high yields of those two monomers and regenerate nylon 66 through repolymerization. Using Toray’s technology to make nylon 66 should halve carbon dioxide emissions compared with production from petroleum-based sources.

Toray looks to initially target automotive materials, establishing technologies to separate other materials in such used equipment as airbags, and technologies to depolymerize nylon 66 and separate and refine monomers. By 2025, the company plans to set up a framework to verify quality and evaluate customers through sample work. It will prepare for full-fledged mass production in around 2030, when stricter plastic recycling regulations are enacted.

The company will develop a comprehensive nylon recycling technologies for both nylon 6 and nylon 66. It plans to broaden its chemical-recycled technologies beyond apparel and automotive materials to other industrial applications to help create a circular economy and contribute to carbon neutrality.

One goal of the Toray Group Sustainability Vision for 2050 is to contribute to a world where resources are sustainably managed. The company will keep undertaking R&D to realize a sustainable, recycling-oriented society, as part of ongoing efforts to realize its corporate philosophy of “contributing to society through the creation of new value with innovative ideas, technologies and products.”