Toray Industries has developed what it believes is the industry’s first solvent-based recycling technology capable of recovering polyphenylene sulfide (PPS) from waste materials — potentially opening a new route for recycling a high-performance plastic used in automotive and electrical applications.

 

Unlike conventional chemical recycling methods that break plastics down into monomers, Toray’s process selectively dissolves and separates PPS while preserving the polymer itself. The approach is designed to remove impurities more efficiently because it avoids the need to decompose the material.

 

PPS is a super-engineering plastic prized for its exceptional heat and chemical resistance. Demand is rising, particularly for automotive components and electrical and electronic parts. But recycling PPS from end-of-life products has remained challenging, with contaminants difficult to remove and few effective recycling technologies available.

 

The challenge is rooted in PPS’s chemical resistance: virtually no solvents can dissolve the material.

 

Toray says it overcame that barrier by drawing on decades of PPS manufacturing expertise. Its technology selectively dissolves and crystallizes PPS from waste materials, separating out glass fibers and other impurities in the process.

 

The recycled PPS retains the same molecular weight and melting point as virgin PPS, according to the company.

 

A preliminary Toray study also indicates that PPS recycled through the new technology may produce lower cradle-to-gate greenhouse gas emissions than the company’s virgin PPS. Toray is continuing demonstration testing to verify the potential emissions reductions.

 

The company has now moved beyond the initial study and is scaling up the technology through a fiscal 2024 project backed by Japan’s Ministry of Economy, Trade and Industry, titled “Support for enhancing the resilience and autonomy of circular economy systems through industry-government-academia collaboration.”

 

Toray is targeting commercial supply around 2030.

 

The company plans to work with partners across the automotive, recycling and other industries to build a resource-circulation system covering the full chain — from collecting PPS-containing waste to putting recycled PPS back into use.