Polystyrene functional barrier safety confirmed

Styrenics Circular Solutions (SCS), the value chain initiative to realise the circular economy for styrenic polymers, has announced that polystyrene (PS) can be used as a safe functional barrier for mechanically recycled PS (rPS) in rigid food packaging.

Through findings supported by a scientific study performed by Fraunhofer IVV, the capacity of PS as a functional barrier by using purposely contaminated rPS as middle layer in a coextruded ABA structure was confirmed. The low diffusion properties of PS, similarly to PET, enable the safe use of mechanically recycled PS in food contact applications behind the PS functional barrier. Fraunhofer IVV performed rigorous testing on real yoghurt pots, proving the safety in an ABA structure with up to 50 per cent recycled polystyrene content. The results are applicable to all rigid thermoformed PS packaging.

Jens Kathmann, Secretary-General of SCS, said: “This is another significant step for SCS. Now, we have not only multiple recycling technologies in place, from food contact mechanical recycling, dissolution to the chemical recycling technology depolymerisation, all of which enable easy recycling of post-consumer PS waste to food contact material, over and over again. We also have multiple mechanical processes, like those of our partners NGR and Gneuss, which have proven to recycle PS to food grade standards. In addition, this study now demonstrates a second safe solution for incorporating mechanically recycled PS content in food contact materials. These results again broaden the range of circular options for the PS value chain.”

Claudio Bilotti, Polystyrene Marketing Manager of Versalis (ENI), added: “This is exciting news as the value chain now has another solution for incorporating rPS into food contact applications that can be placed on the market right away. The proven functional barrier can be used immediately for yoghurt pots with rPS content as well as any rigid PS food contact packaging and expanded PS trays.”