Circular plastics technologies: open loop recycling of waste plastics into new chemicals

Abstract Open-loop recycling is any recycling process where the recycled materials are converted into new raw materials, often of higher value than the parent monomers. Typically, materials recycled through open-loop recycling go on to be used for purposes different from their former, pre-recycled purpose. This means that the input into the recycling process is converted to a new chemical building block, which can be used as an input into another manufacturing process. Open-loop recycling processes usually involve processing various types of products of similar material makeup and change the properties of the material itself (through heat, chemical reactions, or physical crushing). This chapter will highlight promising pathways for upcycling of various plastic waste streams into new applications via open loop chemical and biological recycling processes.