Monomaterial solutions made of plastic are on the rise because they are easier to recycle and fulfil the requirements of the new packaging law. Dow, a manufacturer of polyethylene resins and functional polymers, is working with various cooperation partners on new products to improve the recyclability of flexible packaging made of polyethylene (PE).
The business division Dow Packaging and Specialty Plastics already has around 30 packaging prototypes Dow has developed a range of products together with more than 20 companies, including brand owners, machine builders and packaging manufacturers. In order to bring products to market quickly, Dow maintains worldwide nine so-called Pack Studios, where new packaging solutions can be developed and tested under realistic conditions.
„Pack Studios is able to provide customers and the industry with comprehensive support in the development, testing and validation of PE-based packaging for recyclability,“ said Dr Peter Sandkühler, Global Application Technology Leader Packaging & Speciality Plastics at Dow Europe.
Innovative sealing technology
The companies working together with Dow on recyclable designs for flexible packaging The manufacturer of closures, caps, coffee capsules and injection-moulded packaging components is one of the world's leading manufacturers of packaging components, Menshen.
„The result of our three-year joint development is an innovative technology for the production of pouch packaging made from mono-material,“ explains Sand cooler. „We thought about how we could use pourers in mono-material packaging and came up with the idea of simply reversing the heat, or rather its source, that has to be applied during the sealing process.“
Instead of the traditional Heat from the outside via the film to the shrink-wrapped part this will be raised at the Reverse Spout Sealing Technology now pre-melted before insertion into the bag and sealing.
„The new technology is part of a series of innovations, as we at Dow have been working for several years to expand our portfolio of polyethylene-based solutions for monomaterials.“
Disposal in existing recycling streams
Brand owners are increasingly interested in single-material solutions. Peter Sandkühler: „We have therefore worked with Reckitt Benckiser and Drukpol Flexo a polyethylene film solution for the Finish dishwasher brand which has already been tested in German retail stores and online via Amazon.“
The new resealable bag was developed for the Disposal in the existing recycling streams designed. The Mono-material packaging can be processed on existing systems and enables additional functionalities such as zips, easy opening and the right mix of stiffness and flexibility.
Polyethylene-based packaging can also be High-quality finish and still remain recyclable: With a new High-temperature high-gloss lacquer from Dow, which is applied to the surface-printed PE films of flexible packaging, gives the bag a special look. Through the use of Opulux HGT Optical Finishes laminated packaging structures (PE/PET or PE/BOPP) could therefore be used. be replaced by a PE-based concept. The European manufacturer of plastic and paper packaging, Coveris, is now refining dry pet food packaging with the new product. The packaging is robust and durable, attractive on the shelf and suitable for existing recycling infrastructures.
„The optical properties are achieved by the thin print on the PE film, which accounts for less than five per cent of the packaging, which therefore remains a mono-material according to the Packaging Act,“ explains Sand cooler.
Key role in the circular economy
„Machine compatibility is always an important issue. That's why we also work together with the machine manufacturers, currently with Mespack, the Spanish manufacturer of horizontal flow-wrapping machines. Together we have Prototypes developed on a PE basis and test these recyclable bags for processability and machinability.“ Over the next five years, various Mono-material packaging structures be evaluated in order to optimise the interaction between machine and packaging. „Around 86 billion stand-up pouches are produced every year. If these were recyclable, flexible packaging could play a key role in the circular economy.“
A further partnership currently exists with UPM Biofuels. In the joint project from paper pulp production waste again New raw materials for the production of plastics.
„We then use the renewable naphtha UPM BioVerno in our range of raw materials, creating an alternative source for plastic production.“
The raw material is used, for example, for Production of bio-based polyethylene in Dow's production plant in Terneuzen, the Netherlands. The entire supply chain is organised according to the International Sustainability & Carbon Certification (ISCC) certified and is based on the mass balance approach. The first application already exists: cardboard packaging manufacturers Elopak uses bio-PE for the outer coating of its milk cartons.
[infotext icon] About Dow Packaging and Specialty PlasticsDow's Packaging and Speciality Plastics (P&SP) business unit is one of the world's largest manufacturers of polyethylene resins, functional polymers and adhesives. With Pack Studios, P&SP is an innovator and co-operation partner in the entire value chain for sustainable application development and circular economy life cycle design for plastics.
