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On February 18, Japanese company Toray announced a breakthrough in the chemical recycling of nylon 66. It is reported that this is a supercritical hydrolysis polymerization technique that can depolymerize nylon resin into its monomeric precursors in just a few minutes. It is estimated that Japan’s annual demand for nylon 66 is 100,000 tons, while the global demand is 1.3 million tons. The automotive industry is one of its largest downstream applications, including automotive textiles (such as airbags and tire cords) as well as plastic components (such as radiator tanks, cylinder head covers, and oil pans). One of the main factors driving Toray’s development of nylon depolymerization technology is the regulations regarding recycled plastics in the automotive industry. In 2023, the EU proposed regulations regarding end-of-life vehicles (ELV); these rules stipulate that new vehicles should contain at least 25% recycled plastic (PCR), of which 25% should come from recycled end-of-life vehicles. In other words, 6.25% of the plastic in new vehicles should originate from used cars. Perhaps due to overly strict requirements, the EU reduced it this year from the original 25% to 20%. However, in order to comply with increasingly strict regulations, starting last year, Honda, Nissan, Toyota, along with Mitsubishi and Toray, have collaborated on research into the recycling of plastics used in vehicles. One aspect of this effort involves requiring the collection of used nylon 66 airbags and their recycling into chemically recycled materials. Toray’s recent technological breakthrough essentially involves the development of a depolymerization technology for nylon 66, building upon its existing depolymerization technology for nylon 6. Regarding the depolymerization technology for nylon 6, Toray announced as early as September 2023 that it was collaborating with Honda to test supercritical hydrolysis polymerization technology for the chemical recycling of glass fiber-reinforced nylon 6 components recovered from end-of-life vehicles, claiming that it is possible to depolymerize used nylon 6 into caprolactam monomer in just a few dozen minutes. The depolymerization of nylon 66 requires chemical recycling, which involves recovering hexamethylenediamine (HMD) and adipic acid monomer (ADA). According to Toray, building on the technology for nylon 6, it evaluated the depolymerization reaction of nylon 66 in supercritical water and developed a proprietary technology to suppress side reactions, thereby enabling more efficient and effective recovery of these two monomers. Moreover, compared to petroleum-based raw materials, this technology can reduce carbon emissions by half. Tokyo Riko’s next step is to develop comprehensive nylon recycling technologies for nylon 6 and nylon 66, and to extend its chemical recycling technologies from clothing and automotive materials to other industrial applications. Recently, not only Toray has made breakthrough advances in the depolymerization of nylon, but INVISTA, a major player in the nylon industry, has also announced that it has obtained a patent for a process for the mechanical recycling of nylon. This process enables the production of higher-quality post-industrial recycled (PIR) materials, thereby improving the manufacturing of nylon 6,6. NVIDIA has also filed a second patent application relating to an ammonolysis process for converting post-consumer recycled materials of nylon 6,6 or nylon 6 into hexamethylenediamine and caprolactam.