The trillion dollar question: Have scientists found the holy grail of plastic?

To recycle or not to recycle? That is the difficult question many of us face several times a day when deciding which bin to put our empty packaging in.

Even when we do recycle, our waste still often ends up in the wrong place.

The most recyclable plastic, PET (polyethylene terephthalate), is recycled as little as 20 per cent of the time.

The rest of it ends up being incinerated, or put in landfill or the ocean. Marine plastic costs the world almost £2 trillion a year in damaged and lost resources, according to research last month.

Plastics contain additives like dyes and fillers that give them their specific characteristics. This is both a blessing and a curse – it makes them incredibly versatile and strong when in use but impossible to break down when we’ve had enough.

When different plastics (like food trays, water bottles and bags) are mixed together and melted they inherit a hodgepodge of properties. This makes them much less useful. Most plastic can only be recycled once and will normally be made into things like clothing or part of a shoe that cannot be recycled again.

This week it looked like scientists from Lawrence Berkeley National Laboratory might have solved the trillion dollar question: they made a plastic that can be recycled endlessly and still be as good as new, according to a paper published in the journal Nature Chemistry.

The new plastic is called PDK, or polydiketoenamine. Researchers, led by Dr Peter Christensen, believe this could turn plastic into a “circular” material that can be reused or “upcycled” into other products again and again.

Like all plastics, PDK is made up of large molecules called polymers which are made up of repeating shorter compounds called monomers. However, unlike other plastics, the bonds between the plastic are reversible – they can be infinitely deconstructed and then reconstructed like pieces of Lego.

Scientists were able to break up these bonds by dunking the material in a highly acidic solution. Not only are the monomers separated from ones another but they are also separated from the additives that give the plastic its specific qualities.

The PDK monomers could then be remade into polymers to form a completely new type of useful plastic. This means that a plastic bottle could be refashioned as a computer cable or a plastic bag, for example.

Researchers say that if recycling facilities could process PFK they could start being much more efficient.

However, the research is in its infancy. It’s an exciting development and worth keeping an eye on but not something to bet your life savings on quite yet. And in the meantime, reducing our plastic use remains as important as recycling what we can.