Photo: Tetra Rex ® bio-based 1893 ml, TwistCap OSO34 © TetraPak

Processing, recycling and multi-use are basically also possible with bio plastics, says the Institute for Bioplastics and Biocomposites (IfBB) at Hochschule Hannover –University of Applied Sciences and Arts. Photo: Tetra Rex ® bio-based 1893 ml, TwistCap OSO34 © TetraPak

Bioplastics: Sustainable Alternative or Greenwashing?

In the last decade the bioplastics industry was able to hold its own on the packaging market. Numerous products have supplemented classic applications, and themes like sustainable production and disposal have certainly been able to help prompt the entire industry to change course and have advanced the cause of sustainability in general. Major companies like Danone have recognised the advantages of the new plastics and have brought products like their Activia yogurt pots made of polylactic acid (PLA) onto the market. This earned them both praise and criticism. In the end the company had to withdraw its ad campaign and undertook to no longer advertise with the environmental advantage.

Misleading Marketing Claims?

Despite the positive aspects that bioplastics can bring they still come under critical fire every so often. Recently NGO Environmental Action German (Deutsche Umwelthilfe – DUH) once again accused single-use packaging made of bioplastics of greenwashing. Their criticism: existing life cycle assessments did not reveal any overall environmental advantages over plastics made using fossil raw materials. Many materials, they said, would not be decomposed any more easily than conventional plastics and in some cases would even lead to problems at composting facilities. The non-governmental organisation also complains that the short-life packaging would drive lower-waste and resource-saving multi-use packaging out of the market. But is there anything to these criticisms?

The proportion of PE packaging in McCain’s Chef Fries © stands at 50%. Photo: McCain Germany GmbH, 2017.

Bioplastics as an Alternative

The Institute for Bioplastics and Biocomposites (IfBB) at Hochschule Hannover –University of Applied Sciences and Arts has taken an immediate stance on this. Here they state that the avoidance of waste as well as the promotion of multi-use systems and long-life packaging are aims shared by the university without any reservations. However, bioplastics would not cause any technical difficulty here: processing, recycling and multi-use would basically also be possible with bioplastics.

Open and Honest Communication

In its statement the university department also pointed out that bioplastics are now used in varied industries – for instance in agriculture and building, in the automobile industry, in fibre applications or with consumer goods. Here the alternative plastics certainly bring advantages also due to their non-dependency on limited crude oil resources. The department distances itself from greenwashing and favours honest and open communication about the performance of bioplastics in various fields of application. In certain areas bioplastics could contribute to resource efficiency and a bio-based, closed-loop economy, the statement reads. Furthermore, in the long term there would be no alternative to using renewable and regenerative materials as a basis for plastics because plastics would also be indispensable in many areas in the future.

What are bioplastics exactly?

At this juncture it is worth taking a look at the variety of bioplastics that exist - which has led in several debates and particularly among consumers to confusion. Basically, bioplastics are subdivided into two categories.

Bio-Based Plastics
On the one hand there are bio-based plastics. These are the ones generated from renewable raw materials; for instance maize, sugar beet, algae etc. The proportion of renewable raw materials plays a key role here when calculating carbon dioxide savings. The areas of application are varied. In the field of packaging polylactic acid (PLA) based materials are used; these are pretty similar in application to conventional plastics. Mostly still in research projects alternatives gained from chicory roots are used as waste products from the generation of biogas. The use of waste from areas like forestry (cellulose and lignin) has the advantage of non-dependence on food sources – a criticism which was often lodged against bio-based plastics. With food and drinks PEF (polyethylene furanoate) seems promising. Compared with the conventional material the plant-based raw material displayed increased impermeability towards carbon dioxide and oxygen thereby making for longer storage life for the packaged products.

Biodegradable and Compostable Plastics
Biodegradable and/or compostable plastics can, but do not have to be, made of renewable raw materials. They can just as well be gained from petrochemical sources. However, increasingly a proportion of their raw materials is plant-based so as to continue to improve the product’s environmental footprint.
Basically, the material advantage of biodegradable and/or compostable plastics lies in the functionality and not in the material composition. Some of this packaging can decompose on garden compost heaps while others should be disposed of at industrial composting facilities. Under no circumstances should products of this kind be carelessly thrown away into the environment – an often cited criticism also against the conventional variation of the material. The industry is distancing itself from this: littering is not acceptable regardless of what material it is. Plastics disposal is a top priority – however, this also depends greatly on the individual country and population structure. Numerous countries have no suitable disposal infrastructure; others differ greatly as to the requirements of compositing guidelines. This heterogeneous nature of the market, just like specific application limitations, has made it very difficult for the bioplastics industry to develop a wide product range in this segment. A sensible use of compostable plastics are waste collection bags – something which has prompted general consensus among all stakeholders.

Coca-Cola already has a 30% share of the market with its plant bottle. In 2015 the bottle made of 100% renewable raw materials was already presented at the EXPO in Milan. Photo: CCBCU

The Coca-Cola Example

In 2009 Coca-Cola launched its plant bottle onto the market. Until that time PET bottles were 30% plant-based (sugar beet). The share accounted for by monoethylene glycol (MEG) was replaced. The other 70% of the PET consisted of terephthalic acid (TA) and could not at that time be substituted with a plant-based substance.
At the EXPO in Milan in 2015 the group presented the plant bottle 2.0. This consists 100% of plant-based raw materials. It will still take another few years for the bottle to penetrate the market across the board.