Alternative material, Circular Economy, Sustainability, Recycling

EXPANDED RANGE OF MATERIALS – Part 2, bio-circular materials

27/05/2021 | 2 min read
Stephan Laske

Fresh thinking is needed when it comes to materials, and a change of mindset is required in terms of design. When we talk about the use of alternative materials, it is important that we also take into account current development progress, availability, potential, wider circumstances, and approvals for these materials. After all, these factors are just as varied as the possibilities these materials offer as feedstock for sustainable packaging solutions. We provide an overview of the current situation.

All renewable?

The concept: The smartest raw materials are sourced from nature, where they regenerate time and time again. We examine where and when it makes sense to use these options.

In addition to recycled materials, packaging made from renewable feedstocks offers interesting opportunities for sustainable packaging. These can be divided into different categories, such as vegetarian, vegan, or halal. While fossil-based plastics are made from petroleum, nonfossil plastics can come from a range of sources. Nonfossil feedstocks are divided into three generations:

1st Generation
Primary fruit: Maize, sugar cane, potatoes ...

2nd Generation
Waste material from 1st generation: Straw, leaves, stems ...

3rd Generation
Production waste of variable quality: Tree barks

For instance, bioethanol can be extracted from these various renewable feedstocks and subsequently polymerized. Virgin and renewable materials can also be mixed at any time. Biocircular plastics are used in accordance with the mass balance method. An initial group of Greiner Packaging plants have already been ISCC certified, allowing them to process bio-circular plastics.

Varying availability

PET with a maximum content of 30 percent renewable material is already available. Unfortunately, these are often first-generation feedstocks. Renewable-based PP and PA are very readily available, meet the specifications and approval requirements for petroleum-based PP and PS variants, and from a technical standpoint can form up to 100 percent of a packaging solution, and even make the product carbon neutral. PE variants made from renewable feedstocks are also currently available.

Composting versus recycling

Plastics based on renewable raw materials can be compostable, although they do not necessarily have to be. Some biocircular plastics are also recyclable. The first challenge is to differentiate between industrially compostable plastics and fossil-based plastics in the waste stream. These are often screened out before reaching the composting facility. However, when they do reach the composting facility, they can be composted under precise conditions with regard to temperature, humidity, and so on. However, composting facilities have turnaround times of just a few weeks, which is currently not sufficient for most nonfossil plastics. In addition to industrial composting facilities, it is also possible to compost at home in a composter.

Renewable materials that resemble a standard plastic such as PP, PS or PE in their chemical structure can be recycled in the same loop as these standard polymers.

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