Creating a new recyclable plastic material that is not made from crude oil

It can be said that the world is heavily addicted to plastic, while trying to recycle it, plastic is cheaper to recycle, so unimaginable amounts of plastic waste are dumped and clogged our oceans.

Of all the new plastics ever created, more than 6 billion metric tons of plastic waste (which doesn't decompose but just breaks down into smaller and smaller pieces) has been created, with less than 10% being recycled to date.

Not only is manufacturing the new plastic incredibly wasteful, it also uses feedstocks derived from fossil fuels that need to stay in the ground if we are to avoid climate change.

To make a small impact on this global problem, two materials scientists from Boise State University in the United States have developed a new type of plastic that, unlike existing plastic, is not made from crude oil and its derivatives.

Moreover, small lab experiments replicating industrial processes indicate that approximately 93% of new plastic can be recycled into clean starting materials - even when the plastic is mixed with other untreated plastic waste, paper and aluminium.

In their paper, Alison Christie and Scott Phillips describe the manufacture of a new type of plastic based on poly(ethylcyanoacrylate) or PECA, prepared from the monomer used to make super glue.

Like all plastic polymers, the new product is formed through a polymerization process where single and repeat monomer units are linked together in a chemical reaction to make one long chain.

If manufactured on industrial scales, Christie and Phillips suggest that new, recyclable PECA plastic could replace polystyrene plastic, which is not accepted in most curbside recycling programs.

Polystyrene plastic comes in several forms: expanded polystyrene, also known as Styrofoam, which is used as a lightweight packaging material or to make takeaway food containers; Thermoplastic polystyrene is used to make disposable plates, cups and cutlery.

While it would be great to replace these products with easily recyclable alternatives, polystyrene only accounts for 6% of current plastic waste, which is a small fraction that is a much bigger problem.

Christie and Phillips believe, however, that over time, the new PECA plastic could provide a competitive alternative to other forms of plastic than polystyrene.

"Due to its excellent material properties and ease of recycling, PECA may be useful in contexts other than simply replacing polystyrene, which would further improve the recyclability of plastic waste," they wrote in their paper.

Initial lab experiments from Christie and Phillips indicate that the new PECA plastic has similar properties to existing plastics and is stable in hot and humid environments.

It is this durability and resistance to degradation that makes plastic so versatile but also difficult or impossible to destroy. And yet they contain the building blocks of the new plastic, linked in a neat row, if you find a way to pull them apart. But most plastics are incinerated or discarded.

When it comes to recycling, Christie and Phillips show how the long polymer chains of PECA plastic can be 'cracked' at temperatures up to 210°C and the resulting monomers are distilled into a clean product for further use.

Recycling plastic is a truly noble strategy, but the right regulations must be in place for consumers to join in. Norway has made great strides in implementing schemes that have seen 97% of plastic bottles recycled.

Meanwhile, a recent report by Greenpeace USA found that only about 5% of plastics are currently recycled in the US, after China's recycling industry stopped taking plastic waste from other countries.

The bulk of this plastic waste can be traced back to a few global companies, leading some experts to argue that it is the responsibility of these companies to develop suitable alternatives and reduce their production of single-use plastics to address the root cause of the problem. waste crisis in the world.

As three scientists writing in Science pointed out in 2017 after analyzing the production, use, and fate of all plastics ever manufactured, recycling only reduces future plastic waste generation if — and only if — it replaces primary plastic production.

The study was published in Science Advances.

Source: ScienceAlert