Tests on different types of recycled polyethylene used in blown film production have shown that even when used in small amounts, its presence hampers the ability of the finished film to resist tears and the material’s elongation properties.

Recycling umbrella organisation RecyClass (Brussels; www.recyclass.eu) commissioned tests by Aimplas (Valencia / Spain; www.aimplas.net) to verify the compatibility of common PE film components with the recycling process. These include polypropylene, polyamide and ethylene vinyl alcohol (EVOH) – each tested at 10% concentration level of the total weight of the film.

Three coextruded and unprinted film samples were tested by Aimplas, each containing 90% LDPE and, respectively, 10% PP, PA, and EVOH. The samples were ground and blended with a plain LDPE control sample obtaining a maximum 5% concentration of tested components in the samples, and then extruded. The pellets were then diluted with virgin LDPE obtaining a maximum concentration of PP, PA and EVOH of 2.5% in the samples, and processed to produce blown films.

The findings of PP testing showed the threshold of 2.5% of the total weight of the package increased gels and specks, and decreased tear resistance by 30% and elongation properties by 24%. RecyClass said the results showed that PP components with up to 5% of the total weight of the PE film would have adverse impact on the recycled material.

The organisation has meanwhile announced approvals for three products. RecyClass said following independent laboratory testing it could confirm that the HDPE thin wall tube with an HDPE flip-top cap by Albéa (Gennevilliers / France; www.albea-group.com) is fully compatible with the rigid HDPE recycling stream. The tubes, used mostly as packaging for cosmetics, are made from a 100% mono-material structure with a white masterbatch that incorporates a thin white barrier coextruded HDPE body with an HDPE shoulder and a snap-on HDPE flip-top cap.

RecyClass also gave the green light to EPL’s (Brantford, Ontario / Canada; www.eplplastics.ca) ‘Platina 220 PRO’ and ‘Platina 250 PRO’ tubes, stating tests confirmed that they can be recycled in the HDPE recycling stream. RecyClass said reclaimed plastics generated from the recycling of the tubes can be used to manufacture high-quality blow moulding applications such as containers with up to 25% concentration.

The organisation further confirmed that independent tests had shown Procter & Gamble’s (P&G, Cincinnati, Ohio / USA; www.us.pg.com) single unit dose laundry pouch pack is compatible with the European flexible PE stream recycling. The reclaimed material can now be used in high-end, or even closed-loop applications, it added.