Scientists develop method to repair engineering plastics at molecular level

A team of polymer scientists has announced a breakthrough that could make plastic recycling far more effective by restoring the mechanical strength of damaged engineering plastics at the molecular level. The new technique, described in a recent issue of *Advanced Materials*, uses a targeted chemical repair process that re‑links broken polymer chains, allowing recycled parts to meet the performance standards required for high‑strength applications.

The method, developed by researchers at the National Institute of Materials Science, employs a catalyst‑driven cross‑linking reaction that selectively bridges chain ends without adding filler or plasticizers. In laboratory tests, recycled polypropylene and polycarbonate samples treated with the process regained up to 90 % of their original tensile strength, a significant improvement over conventional reprocessing which typically results in a 30‑50 % loss of mechanical properties. The technique is compatible with existing recycling infrastructure and does not require additional energy‑intensive steps, making it a promising candidate for scaling to industrial use.

If adopted widely, the technology could expand the range of engineering plastics that can be recycled, reducing the need for virgin material in sectors such as automotive, aerospace, and electronics. By preserving the integrity of recycled components, manufacturers may lower costs and environmental footprints while meeting stringent safety and performance regulations. The research community now looks to pilot the process in commercial recycling facilities to evaluate its economic feasibility and long‑term durability in real‑world applications.