Multi-layer barrier films have long been the workhorse solution for complex packaging needs. Yet, although highly functional during their useful life, they tend to pose a problem at the end of life due to their inability to be mechanically recycled.
The growing awareness of this problem, combined with the EU’s upcoming targets for recyclability and recycled content for 2025, have led film and packaging manufacturers to seek other solutions.
Some have turned to collaborations with chemical recyclers, while others have developed mono-material solutions. Spain-based SP Group has partnered with Nurel, the manufacturer of a family of bioplastics called Inzea, to offer the market a bio-based, multi-layer barrier film structure option complete with a sustainable end-of-life solution.
Inzea biopolymers are bio-based, biodegradable and compostable materials with a renewable content of up to 85 percent. The materials are based on non-genetically modified polylactic acid and starch and the entire range is food-contact approved.
Biopolymers have, to date, largely been used for fresh-food packaging, such as bread, fruits and vegetables.
This new film structure makes it possible to manufacture bio-based barrier films suitable for packaging complex foods such as salmon. It is currently already used to package spices; tests are under way for, among others, energy bars, nuts, salt.
The transparent, sealable films can be processed using conventional technologies on existing equipment, said Maria José Alfonso, head of developments at Nurel Biopolymers. She added that that was, in fact, the biggest challenge of the project: to achieve a compostable material that could be disposed of as organic waste at the end of life - and processed without difficulty in any conventional blown film extruder while maintaining its high oxygen barrier properties.
“This film meets all the quality requirements for the packaging of foods such as smoked salmon, its processing has been very simple and the oxygen permeability results are excellent, comparable to EVOH high barrier structures," said Maria de Guía Blanco, R&D Project Engineer at SP Group.
The biopolymers used to produce the film are OK COMPOST certified and therefore meet the requirements for industrial compostability.
SP Group is targeting the flexible film markets for packaging applications of fresh, dry or refrigerated products that require a high barrier to oxygen with the new films.