How can the mountains of discarded packaging be systematically recycled in high-quality plastic products and containers? In a joint project, schäfer-etiketten, Polifilm and the self-adhesive solutions specialist HERMA are pioneering a clever closed material cycle for polyolefin (PE and PP) packaging. It has now been nominated for the Plastics Recycling Awards Europe in the category Product Technology Innovation; the prize-winners are to be announced in Amsterdam on 26 March 2020. The drugstore chain dm-drogerie markt has also expressed an interest in the project. In 2018 the company initiated a recycling platform to foster the sharing of ideas concerning the circular economy. “This is a very promising project. It can effectively and substantially increase the recovery rate of household plastic packaging waste while at the same time improving the quality of the pellets produced during recycling,” says Dagmar Glatz, who oversees sustainable packaging on behalf of dm-drogerie markt. The concept devised by schäfer-etiketten, Polifilm and HERMA therefore addresses two key issues at once – waste recycling and the innovative use of recycled materials.
Regarded as unprecedented worldwide
Based on a HERMA self-adhesive material and a Polifilm product, schäfer-etiketten has produced a PE label consisting entirely of post-consumer recycled (PCR) material recovered from milk bottles. Even the masterbatch containing the white pigment is a PCR PE product. A label with this specification is currently thought to be without equal worldwide. The label alone illuminates the valuable application scope that exists for high-quality recycled PE. In the autumn, Polifilm, schäfer-etiketten and HERMA received the German Packaging Prize for another PE label. It is also a completely recycled product, but in this case originating from equal portions of domestic refuse and industrial waste. “At present, polyolefin packaging is often recycled without the labels being removed, so that the recovered material contains printing inks, varnishes and adhesives as well. Quality shortcomings are therefore inevitable,” explains Volker Hurth, the Cosmetics Key Account Manager for schäfer-etiketten. “In consequence, we can produce vast quantities of flower pots and park benches from recycled materials, but continue to use virgin plastics or, at best, only small amounts of recovered materials in cosmetics packaging.”
Wash-off adhesive overcomes major obstacle
The innovative HERMA wash-off label adhesive 62Rpw, which is used in the product nominated for the recycling award, has now cleared a major hurdle blocking the pathway towards the fully fledged recycling of polyolefin packaging. It allows the labels to be washed off without leaving any residue so that they can be removed from the recycling stream together with the adhesives and inks. In the case of polyolefin packaging, a practicable
solution to this problem has been lacking thus far. “This marks a highly significant step towards the recovery of high-purity pellets from shampoo bottles for example. It’s the only way of radically reducing the use of virgin PE and conserving resources,” comments HERMA managing director Dr. Thomas Baumgärtner. “Last year we demonstrated the capabilities of our special wash-off adhesive in combination with PET bottles. We are now very proud to be offering a similar solution for other PE plastics.”
Not only clean, but pure as well
The relevant wash-off tests were performed on the premises of Sorema, a leading supplier of plastic recycling systems. Labelled PE shampoo bottles provided by dm-drogerie markt were comminuted and then washed at 70 degrees Celsius. In the next step, the plastic flakes and label film particles were separated by air separation. “The tiny flakes were completely free of ink and adhesive, so that we were able to recover a high-quality raw material,” confirms Lorenza Lombardi, manager of the R & D Laboratory with Sorema. The goal of achieving a more or less continuous cycle is now within reach. “We simply have to combine these two innovations with intelligent sorting technology, for instance using invisible barcodes or fluorescent markers,” remarks Volker Hurth of schäfer-etiketten. “We have engineered a solution capable of genuinely enhancing the material cycle – provided that recycling operators switch from cold to hot washing for PE/PP,” he continues. “It’s already a matter of course with PET bottles, so that it must be worthwhile adopting the process for PE/PP as well.”