Expanded polystyrene is everywhere, and for good reason. It’s light, and sticks readily to most things, making it a good protective material to encase delicate objects like televisions, or maybe a china vase. And, importantly, it’s also cheap and relatively easy to manufacture.
Once those items have been delivered and unwrapped, however, disposing of large piles of expanded plastic foam is harder said than done. Polystyrene is slow to degrade – according to Washington University it can take up to 500 years to decompose – and its toxic chemicals can have a damaging effect on the environment, seeping into water supplies and harming wildlife.
Then there’s the manufacturing process, which utilises chemicals such as styrene and benzene, which have been known to cause adverse effects on the body, contaminate food and release hydrocarbons into the air to produce hazardous air pollutants. In short, there is room for significant ecological improvement.
For Ali Harlin, research professor at VTT, a Finnish research, development and innovation centre specialising in materials like bio-based raw materials, these are all valid reasons to look for an alternative form of packaging. “Of course, polystyrene foam is a light, affordable material, and reasonably easy to develop,” he explains. “But, the problem is always what to do with it once you’ve opened your package, because the volume of the foam is extreme, and it’s hard to collect that material back and recycle it into anything.”
To develop eco-friendly alternatives to replace polystyrene and other plastics, VTT has been creating versatile forms of packaging from wood.
These materials look and feel the same as plastic, but have a range of key benefits. Most notably, they are biodegradable and easy to recycle. And, due to unique foamforming technology, they can be produced with short and long fibres to improve their protective properties, and be combined with polymer, or biopolymer fibres, for greater versatility.
Foam-formed cellulose-based materials are also an attractive alternative to polylactide foams (PLA), made from corn and corrugated board, and moulded-fibre products made from wood pulp, which are twice as expensive to produce as polystyrene, and difficult to recycle.
As Harlin notes, while much of this technology is still in an experimental phase, the company offers laboratory-scale demonstrations of its packaging materials, and these bio-based solutions are getting significant recognition.
“The problem is always what to do with it [polystyrene] once you’ve opened your package because the volume of the foam is extreme, and it’s hard to collect that material back and recycle it into anything.”
VTT won sustainable packaging prizes in 2018 for its unique cellulose-based substrate, and was awarded further recognition by the Ellen MacArthur Foundation in the same year for its efforts to solve the global microplastics problem. It is an issue that VTT is working tirelessly to overcome. It can draw on more than 10 years of experience when utilising the innovative technologies that allow these biological materials to solve technical issues and become more commercially viable – like drying and converting the foams on an industrial scale, without losing much moisture and mass.
“At the moment, pulp costs something like €500–600 a tonne, when plastic is something like €1,400–1,600,” Harlin says. “So, cellulose should be a winning concept, but the problem is that the conversion of cellulose pulp into a packaging material is still much clumpier than the plastic.”
For Harlin, the undeniable benefits of using biodegradable materials, the growing influence of international organisations such as the Ellen MacArthur Foundation – which has encouraged companies like Evian, L’Oréal, Mars and The Coca-Cola Company to adopt 100%-recyclable packaging by 2025 – means that they have a bright future.
Meanwhile, a heightened public consciousness about the damaging effects of using plastics will only put more pressure on companies to stop using polystyrene and other harmful substances. “At the moment, we produce probably as much pulp as plastic on the planet, but the pulp is a renewable, recyclable material. So, if we are clever now, we can stop the expansion of plastic consumption,” Harlin says. “But if we don’t do it now, it could double in the next two decades.”