The innovative recycling company from Merseburg, Germany has tested the performance of its Newcycling LDPE recyclates in shrink films during several projects undertaken over the course of this past year. Primary test results showed that the recyclates were able to deliver on the key functional issue of shrinkage. Film thickness was able to be maintained at the same level as with virgin plastics. Formulation of the shrink films and extrusion parameters remained close to the virgin feedstock version.
Collation shrink film is a demanding packaging application – for virgin polymers and all the more so for recycled materials. It needs to have a specific toughness, holding force, and shrink performance for it to guarantee package integrity as well as the necessary stability for storage and transport. Process parameters should remain constant when switching from virgin to recycled feedstock. Beyond this, as the film may be used as secondary packaging for bundling several products, making it the first thing the consumer sees, optics need to be of a high-enough quality.
‘Our LDPE recyclates are suitable for a broad number of end markets. When it comes to shrink films, they represent an opportunity for the beverage industry to push its use of secondary raw materials in applications such as shrink sleeves or multipack sleeves’, explains Klaus Wohnig, CEO of APK, in discussing one of the possible target markets for the product.
During the projects that focused on multi-layer collation shrink films, ambitious substitution rates for virgin feedstock, ranging from 30% to 100%, were tested. The 30%-55% scenarios produced impressive results: the shrink film was nearly indistinguishable from that made of virgin material. Substituting virgin plastics for these amounts of secondary raw materials would already allow for a decisive reduction in emissions. Newcycling LDPE recyclates produce nearly 50% fewer emissions than virgin LDPE types.
APK’s dissolution recycling process, the Newcycling® technology, can easily separate different polymers in multilayer plastic packaging – up to now, deemed non-recyclable – and transforms the target polymer into re-granulates with close to virgin properties. Dissolution recycling is an advanced physical recycling technology. Building on a mechanical pre-treatment step, it adds a solvent-based process step, during which the target polymer is separated and purification of contaminants, such as various additives or organic residues, also takes place. APK’s recycled LDPE, used during the shrink film tests, is marketed under the Mersalen brand. It is derived from complex PE/PA multilayer film waste.
As Newcycling is a physical process and does not affect the molecular chains of the polymer, cost- and energy-intensive re-polymerisation is not needed. The technology is to be considered besides and complementary to standard mechanical recycling as well as innovative chemical processes (such as solvolysis) for this matter.
