Recycled plastics could find their way even into car dashboards – VTT’s method produces higher-quality recyclates

The environmental crisis and evolving EU regulation are driving the quest to find new solutions in plastics recycling. Currently, only eight percent of the plastics used in the EU come from recycled sources. With technology and expertise found in Tampere, Finland, recycled plastics can now reach top quality levels, advancing their use even in demanding applications. 

Plastics are everywhere. Everyday products such as clothes, food packaging, and household appliances are full of polymers – even a typical car may contain up to a couple of hundred kilograms of plastic.

When plastic is recycled from waste back into raw material, its quality deteriorates. That is why recycled plastics have so far been used mainly in shopping bags and cleaning supplies, but rarely in demanding products such as cars or food packaging.

Another reason for the underuse of recycled plastics is that many component manufacturers have optimised their production lines for virgin plastics. Affordable virgin plastics imported from outside the EU also slow down the development of the recycling business.

This situation is about to change. The EU’s new Packaging and Packaging Waste Regulation (PPWR) sets minimum requirements for the proportion of recycled plastics used in packaging. Jani Pelto, Principal Scientist at VTT, specialises in polymer materials engineering – and he sees the change coming fast.

“From January 2030 onwards, even packaging materials in direct contact with food will need to include a certain proportion of post-consumer recycled plastics. And the targets for recycled content will keep rising step by step,” Pelto says. 

Currently, mechanical recycling is the only significant plastic recycling method used on an industrial scale. However, solving the recycling challenge requires a smart combination of mechanical, physical and chemical recycling.

According to Pelto, stricter regulations should not pose a problem from a technological perspective. If there is a will, plastic recycling could function just as effectively as metal recycling does today.

“When plastics are processed correctly, we can achieve top-quality materials with a recycled polymer content of up to 70 or 85 percent. If, for example, the automotive industry were to adopt this approach across the board, it would have a massive impact on the recycling market. The real challenge is that people don’t quite believe plastics can be recycled in the same way as metals.”

According to Pelto, the greatest success story in plastics recycling is the deposit system for PET bottles. Thanks to long-term development driven by the beverage industry, bottles already contain a decent share of recycled content.

“The same thinking now needs to expand to other popular packaging plastics, such as polyethylene and polypropylene,” Pelto says. 

VTT has developed a globally unique solution for mechanical recycling of plastics. The key is stabilising the quality of recyclates so that their properties can be guaranteed – just like virgin plastics.

In VTT’s process, sensors monitor factors such as the melt viscosity of the material. Whenever the system detects variation, the composition and additives of the recycled plastic can be automatically adjusted. This ensures consistent quality and keeps material properties within a defined range.

“We call the process advanced rheology control. In practice, it’s an automated quality adjustment system that gives industry confidence in both the quality and desired properties of recycled plastics. On top of that, we can document everything coming out of the process through sensor data,” Pelto says.

Thanks to this controlled process, recycled plastics can be used in increasingly demanding applications. VTT has even demonstrated a prototype where recycled plastic replaced a car’s metal crash box.

Alongside the control system, VTT has also invested in the upstream phases of mechanical recycling – washing and sorting of plastics. Multiple sensors can be integrated into the processing line, and the data obtained by them can be combined. The line can be easily adapted to customer needs.

With careful processing, recycled plastics can be turned into products of equal or even higher value than their originals.

“This is not distant future. Very soon, packaging plastics will be recycled back into new packaging, and technical plastics will be reused in technical applications. The plastic circulation will inevitably increase – and the demand for consistent, high-quality recyclates will grow,” Pelto says. 

Read more about VTT’s circular economy services for plastics here.