Extrusion International 5-2026

56 Extrusion International 5/2026 RECYCLING Mix of Technologies Required to Recycle Engineering Plastics A mix of recycling technologies is necessary to ensure that a broad variety of plastics can be recycled. Unlike high-volume commodity plastics such as the polyole- ns used in packaging, specialty plastics often require recycling technologies tailored to their speci c proper - ties and applications. This applies, for example, to com- pounded polyole ns, polyurethanes and polyamides. These materials are designed for demanding uses, such as automotive applications, where standard plastics of- ten do not provide the required performance. This is the subject of a recent article by BASF researchers in the prestigious U.S. academic journal Accounts of Materials Research. Achieving circularity for plastics from heterogeneous waste streams requires two things: scalable sorting pro- cesses and the right mix of recycling technologies. The suitable approach depends on the material itself as well as on the composition of the waste stream. “There is not one single standard technology for recycling engi- neering plastics,” emphasized lead author Dr. Bernhard von Vacano, head of the Plastics Circularity Research Program at BASF. “Instead, it is crucial to have an in- telligent mix of various complementary technologies adapted to particular plastic waste streams. The aim is to produce high-quality recycled materials and achieve a closed loop for engineering plastics.” Various paths for plastic recycling The most common technology is mechanical recycling, in which plastics are sorted, crushed and melted. This process is energy-ef cient but does not work with all plastic types and requires clean and homogenous waste streams. Mechanical recycling is particularly well suited for packaging waste materials with large volumes of relatively pure polymers and limited amounts of addi- tives. Nevertheless, quality and hygiene requirements can restrict the use of mechanically recycled materials in new packing products. There are limits to mechani- cal recycling for plastics used in technically demanding applications, as suitable waste streams are often scarce and plastic products frequently contain complex poly- mer compositions. In contrast, solvent-based recycling is suitable for more complex waste plastics. In this process, a solvent is used to selectively dissolve, separate and clean one type of plastic. For example, polyamides can be recovered from scrap vehicles and used again in the manufactur- ing of new components. Another important recycling technology is depoly- merization. Here, plastics are broken down into their building blocks and put back together again. BASF re- searchers have developed loopamid®, an innovative process that enables circular textile-to-textile recycling of polyamide 6. Waste textiles can thus be transformed back into polyamide bers with the same high-quality standards as conventional polyamide 6. In early 2025, BASF started up its rst commercial loopamid produc - tion facility at its Caojing site in Shanghai, China. Plastics from very heterogeneous waste streams, which often end up in incineration plants, can be re- cycled in thermochemical processes, such as pyrolysis or gasi cation. These technologies require a lot of energy. In pyrolysis, the long-chain polymers of the plastics are broken down into short hydrocarbon chains, which can then be utilized again as a raw material (pyrolysis oil). Gasi cation produces syngas, which can be deployed as a chemical feedstock in production. Supportive regulatory frameworks are key for the scale-up Numerous BASF pilot projects have demonstrated that many recycling processes for polyurethanes and poly- amides are technically feasible and can convert waste plastics back into virgin-quality feedstock. “However, two key conditions must be met before these technolo- gies can be deployed at scale and to enable business cases for large scale investments. First, we need effec- tive waste management systems that keep plastics in the loop over the long term. Second, policymakers need to provide clear and reliable regulatory frameworks that support recycling,” said Dr. Jens Hamprecht, co- author of the publication and Vice President in BASF’s Performance Materials division. BASF www.basf.com