Experts: Tim Börner (HES-SO Valais-Wallis), Roger Marti (HES-SO Fribourg), Maria Stewart (Plastics Innovation Competence Center), Manfred Zinn (HES-SO Valais-Wallis)
The use of bioplastics represents a great opportunity to improve the sustainability of plastic products. At present, regulations and high costs, as well as a lack of technical implementation in products that offer properties similar to those of established products, are hindering the spread of applications. For Switzerland, the development of high-tech and niche products has great potential, which could be tapped with targeted funding. In order for the topic to gain momentum, it is essential that firms, legislators and the general public alike realise that plastic waste is a valuable resource, and that targeted use of bioplastics could make a sustainable circular economy a reality.
Picture: Brian Yurasits, Unsplash
Bioplastics are either bio-based, biodegradable or both. Thus, there are bio-based plastics, such as bio-PET, that cannot biodegrade in the environment. These bio-based plastics, also called drop-in bioplastics, use varying proportions of natural renewable feedstocks and fossil resources as carbon sources, and are identical to their fossil counterparts both chemically and mechanically. Renewable feedstocks include corn starch, rapeseed oil, cane sugar, lignocellulose and, on a small scale, wastewater and waste streams from agriculture and food production, as well as CO2. It is also possible to make biodegradable bioplastics from biological and/or fossil resources. Some, such as polylactic acid (PLA), are entirely bio-based, while others, such as polybutylene adipate terephthalate (PBAT) from the polyester group, are completely fossil. The biodegradability of these plastics also depends on environmental conditions.
Bioplastics have manifold applications and are used in car manufacturing, chemistry, electronics, agriculture, packaging, medical technology, toys and textiles. The focus is often on bio-based, rather than biodegradable. Some of the products end up in the fossil plastic products cycle or, due to a lack of knowledge, are disposed of with organic green waste and not recycled.
In principle, the future applications are unlimited – provided there are enough, ideally sustainable, resources. In Italy, for instance, bioplastics are already being produced using waste oil from the catering sector. In the future, it will be essential to produce bioplastics from renewable raw materials that do not compete with food production and are demonstrably climate-friendly. Algae are an almost infinite source; however, there is still a lack of relevant knowledge and large-scale sustainable cultivation. One initial step could be the replacement of small plastic parts in technical devices, but as the market is small, efforts in this regard are not very ambitious. At present, 450 million tonnes of plastic are required worldwide on an annual basis. It would be unrealistic to attempt to completely replace this with bioplastics in the next few years.
The main advantage of bioplastics is that the use of fossil resources is reduced or avoided. Bioplastics decrease resource consumption, leave a generally smaller energy footprint and cause fewer emissions than conventional plastics. With biodegradable plastics, the environmental impact of long-lasting micro- and nanoparticles can also be significantly reduced or even prevented. However, bioplastics also raise the question of whether they are any more sustainable than fossil plastics as future single-use materials for food packaging, or whether such applications would actually be better replaced by recyclable packaging and return systems. The current trend is towards biodegradable plastics that are also recyclable and thus compatible with the cradle-to-cradle principle of the continuous circular economy, even though this is an area where the plastics and waste industries are still in the early stages. Drop-in bioplastics can be recycled using conventional methods, but as with plastic recycling in general, separated and pure material flows are needed.
Thus, waste collection and sorting have a crucial role to play. There are now good technical solutions capable of identifying and automatically sorting different types of plastic. While biodegradable plastics are already being composted, mechanical or chemical recycling still needs refinement. At present, the amount of bioplastics to be recycled is too small to operate two parallel systems and to recycle consistently and economically. A waste fee could help compensate for the higher costs of new materials and technologies. Increased use of recycled feedstock could be stimulated by legislation, as proposed in the European Green Deal, which mandates a certain minimum amount of recycled material in packaging. Switzerland could play a pioneering role by strategically advancing the principle of cost compensation, as parliamentary initiative 20.433 ‘Strengthening the Swiss circular economy’ seeks to do.
Bioplastics research and commercialisation are still in their infancy in Switzerland, and represent good opportunities for universities and firms with regard to projects, patents and new business models. A lot of hope rests on the use of bioplastics for medical devices, such as stents and heart valves, because they are degradable and well tolerated by the body. However, bioplastics can also be beneficial for applications such as composites, adhesives or shoes, where the materials currently cannot be recycled, have a relatively large carbon footprint and contribute to microplastic pollution. Firms are seeing interesting sustainability-related opportunities emerge: The use of bioplastics is likely to become relevant to the carbon footprint of manufacturing companies and banks can reflect the issue in their investment funds. Although mass plastic production has been of little relevance to Switzerland as yet, high-tech and niche products do represent good opportunities in terms of both development and applications.
On an economic level, the current high costs of bioplastics are preventing their widespread use. The impact on people’s pockets will play a key role. Inadequate development maturity and the lack of technical implementation in products that offer properties similar to those of established products are other factors hindering widespread market rollout. Drop-in bioplastics are an exception. Both in Switzerland and internationally, regulations mean that the requirements for approval of bioplastics are stricter than for petroleum-based products. From a scientific point of view, scaling up the synthesis processes, and adapting material properties like colour and consistency to individual needs are particularly challenging. The Swiss population is not yet sufficiently aware of the topic, even though microplastic pollution is clearly detectable in the country’s ground and waterways.
Within Switzerland, networking among researchers is scant and there is a lack of relevant study programmes at the country’s universities. In the EU, there are funding and networking opportunities that Swiss researchers are effectively denied now that Switzerland is classified as a non-associated third country. Targeted funding would be an important means of providing education on bioplastics in the Swiss research hub. A Federal Council report of 23 September 2022, which the Federal Council compiled to fulfil four postulates, offers hope. It might also be worthwhile studying conditions that have prompted a high level of research activity in other countries.
Sensibly devised regulations are helpful because they encourage firms and the general public to adopt new ways of thinking and acting. For instance, regulations on the design and size of plastic packaging, along with corresponding information on environmental impact, as is standard for cars and refrigerators, are conceivable.
Politicians would be well advised to raise the general public’s awareness of the value of resources and plastic waste. In ideal circumstances, the realisation that plastic waste is a valuable resource will soon take hold.