Self-healing recyclable plastic

The supramolecular plastics decompose much more easily than traditional polymers and can be used as an adhesive

Spotted: Traditional polymer plastics environmentally destructive because they degrade and regenerate poorly in nature. This lack of degradability is the result of the inherent strong force of covalent bonds that link monomers for the formation of polymers. Scientists have suggested making polymers connected by non-covalent bonds. However, these bonds are usually not strong enough to hold molecules together.

In response, researchers at the MediCity Research Laboratory at the University of Turku, Finland, have discovered an alternative – a physical concept called liquid-liquid phase separation (LLPS). LLPS’ novelty stems from its ability to strengthen the bonding force between molecules without forming covalent bonds.

The result is a new category of material called supramolecular plastics. The dynamic and reversible nature of the non-covalent interactions makes the material degradable and highly recyclable. Furthermore, the mechanical properties of these plastics are comparable with conventional polymers, meaning they have the potential to replace conventional polymeric plastics without sacrificing durability or strength.

During the investigation, which was led by senior researcher Jianwei Li and published this month in the Angewandte Chemie journal, the scientists found that the material could ‘self-heal’. In other words, it could be quickly reunited after being fragmented. In addition, the material worked as an adhesive, holding a 16 kilogrammes of weight for over a month.  

Future applications of supramolecular plastics could potentially reduce the amount of waste produced by plastic pollution. Other innovations recently spotted to tackle the plastic pandemic include new material made from the non-edible parts of plants as well as an enzyme-based technology that can break down plastic.