Is there a role for plastics in a fibre-based future?

While the world is increasingly turning to fibre-based packaging solutions, there is still a case to be made for plastics.

If you break it down, you’ll see long, flexing chains of atoms or small molecules bonded together, creating a repeated pattern. This structure is characteristic of plastics, these polymers that revolutionized everything from food packaging and garden tools to toys and furniture.

These versatile polymers have come under scrutiny during the last ten years as disturbing images of polluted oceans and suffering animals have increasingly popped up in our social media feeds.

Quite rightly so. 50 years of research and development has made plastics into a versatile and cost-efficient material suitable for most needs. The abundance combined with affordability has led to wasteful behaviour and hence we have ended up with an immense litter problem.

Policymakers are acting on it. China has enforced strict bans and EU is in the final stages of enforcing the so called single-use plastics directive. While the directive won’t categorically ban everything containing plastics, it does seek to change our consumer patterns and our behaviour when it comes to marine littering. All good with that. However, one should not put a negative bad label on all things plastic.

Different ways to make plastics

Kalle Saarimaa is responsible for recycling and waste solutions at Finnish energy company Fortum. He is calling for a more nuanced debate around plastics.

“The discussion about plastics is very complex and there are no simple truths. First, you need to define what plastics really is”, he says and goes on explaining that while we tend to refer to plastics as a synthetic material, it’s in fact a chain of carbon and hydrogen atoms that you can produce in different ways. Indeed, nature has produced polymers since the beginning of life: these long, flexing chains of carbon and hydrogen molecules are found in every living organism from plants to your DNA.

Plastics based on fossil material such as oil, is usually what comes to mind in the plastics debate, but plastics can also be produced using biomass (think tall oil from pulp production) or through a method called power-to-plastics, where you combine CO2 with hydrogen that you get through electrolysis. CO2 can be captured from the smoke arising from burning incinerating waste, further adding to circularity. There are some challenges though.

The problem with biomass is lack of feedstock

“It’s an important part of the material portfolio, but it will remain a niche thing”, says Saarimaa. While power-to-plastics is still in its infancy, he sees this technology as a viable future alternative.

“Currently we largely see incineration as the final stop for waste, when in fact it could become the very launch pad”, he says, referring to the carbon emissions that could be captured from the smoke and be used for production of new plastics.

“But it requires a lot of energy and hence wider use of renewable energy is a condition for large-scale adoption.”

Then there is chemical recycling, where you break down the polymer back to atoms through pyrolysis or other methods. Although chemical recycling makes the recycled plastics as good as virgin, massive investments are needed and it’s unclear who should foot the bill.

Closing the loop with recycling

While new technologies are being developed, the best option for now is to make the most out of mechanical recycling. In Europe, only about 30% of all plastics produced is recycled and in the US the figure is not even 10%, leaving over hundreds of million tonnes out of the circle. This needs to change. But how?

Closing the whole loop from designing packaging to collecting the waste and have a waste-handling facility process it to recycled material fit for further use, is a complex equation with lots of different parties involved.

“While the infrastructure is largely in place in Europe, it is lacking in other parts of the world, leading to plastics left in nature and waterways. In Europe we need wider adoption of recycled plastics in new products.”

Finding further use for recycled plastics

While plastics PET bottles have been something of a success story in terms of mechanical recycling and reuse, it’s a bit trickier when it comes to food packaging. The shift towards fibre-based food packaging is well under way, but the fact remains that certain food stuff needs an efficient barrier to hinder the food quality from suffering. There are stringent rules on reusing recycled food packaging due to potential migration of harmful substances which makes it difficult to achieve circularity for food packaging containing plastics.

Still, food packaging stands for a large part of the plastic waste, so closing that circular loop would make a big difference. Switching to monomaterials rather than using multilayer laminates is a necessary first step to make the most of mechanical recycling.

And then we need to create a market for recycled plastics. There is no point in recycling plastics on a large scale if the recycled materials are not put back in the loop. To encourage more use, some countries are enforcing taxes on products that contain no recycled plastics.

At the end of the day, it comes down to shifting our attitude.

“We need to start treating plastics as a valuable resource that cannot be wasted”, says Saarimaa.

The discussion on plastics in packaging is indeed complex. How should one look at it?

“There is no ‘one solution fits all’. What you really need is a large portfolio of different materials and technologies from where you choose a suitable solution while considering the requirements for food safety, recycling infrastructure, waste handling facilities and reuse of the packaging.”