The eco-friendly "supramolecular" plastic is therefore highly recyclable and, with careful tuning of its water content, can be turned into an adhesive or even instantly self-heal when damaged.
The reason conventional plastics persist in the environment for so long is the incredibly strong chemical connections between the monomers within them. These particles link up to form polymers through what are known as covalent bonds, but scientists hope to fashion more environmentally forms of the material based on non-covalent bonds instead.
These weaker connections are better suited to degradation and recycling of the material, but do come at a cost in terms of mechanical performance. We have looked at some interesting examples of these "supramolecular" materials in the form of hybrid polymers for drug delivery, self-assembling plastics and adhesives that work at extreme temperatures.
By leveraging a technique called liquid-liquid phase separation (LLPS), the authors of the new study say they've now developed a supramolecular plastic with the mechanical strength of conventional plastic. The material contains non-covalent bonds of high strength that are reversible, which enables it to be degraded or recycled after use, along with some other useful properties.
The plastic features a "remarkable" ability to be stretched and deformed with low water content, while increasing that water content turns it into an adhesive. Further, this higher water content enables the plastic to self-heal instantly when broken into pieces.