5WS of PDK Recyclable Plastic

摘要

All plastics — from water bottles to automobile parts — are made up of large molecules called polymers, which are composed of repeating units of shorter carbon-containing compounds called monomers. During processing at recycling plants, plastics with different chemical compositions are mixed together and ground into bits. When chopped-up plastic is melted to make a new material, it's hard to predict which properties it will inherit from the original plastics. This has prevented plastic from becoming a "circular" material whose original monomers can be recovered for reuse for as long as possible, or "upcycled" to make a new, higher-quality product. The new plastic, called poly(diketoenamine), or PDK, can be disassembled into its constituent parts at the molecular level and then reassembled into a different shape, texture, and color again and again without loss of performance or quality. With PDKs, the bonds of conventional plastics are replaced with reversible bonds that allow the plastic to be recycled more effectively. Unlike conventional plastics, the monomers of PDK plastic could be recovered and freed from any compounded additives simply by dunking the material in a highly acidic solution. The acid helps to break the bonds between the monomers and separate them from the chemical additives that give plastic its look and feel.