According to researchers at Kaunas University of Technology (KTU), bioplastics will make little difference unless synthetic plastics are used responsibly. However, novel solutions are required to address today’s worldwide environmental catastrophe, and bioplastics can play a critical role in this process.
Dr Ramunė Rutkaitė. Image Credit: Kaunas University of Technology
The average EU citizen generates 36 kg of plastic packaging waste every year. Long-term estimates are equally dismal, with global plastic waste expected to triple by 2060. Increasing consumption is driving the quest for alternatives - biodegradable and long-lasting materials that can not only replace but also exceed synthetic plastics.
Bioplastics are frequently mentioned as one solution to a more sustainable future, but few people realize that this material is not the outcome of current scientific research. Maurice Lemoigne, a French researcher, discovered a means to create bioplastic polyhydroxybutyrate in 1926; unfortunately, this answer was overshadowed by the low-cost, seemingly infinite oil business.
The implications, however, are visible today: dwindling oil resources and a staggering 400 million metric tons (equivalent to the weight of nearly 40 Eiffel Towers) of synthetic plastic waste generated in 2021 alone.
Can bioplastics save the planet?
Can Bioplastics Save the Planet?
Dr. Ramunė Rutkaitė, a professor at KTU, defines bioplastics as a diverse variety of materials with varying biodegradability and sources.
Plastic is considered to be a bioplastic if it is made from renewable natural raw materials derived from biomass, natural or genetically modified organisms, or if it is biodegradable. There is a third type of bioplastic, however, which has both characteristics.
Dr. Ramunė Rutkaitė, Professor, Kaunas University of Technology
According to the KTU professor, the majority of bioplastics are now made from agricultural, or first-generation, feedstock, which primarily consists of hydrocarbon-rich plants such as potatoes, corn, sugar cane, and wheat. This choice of bioplastic raw material creates an ethical question: can food be used to make bioplastic bags, for example?
Dr. Rutkaitė added, “In this case, there is no doubt that feeding the world is the priority and bioplastics should be produced using second and third-generation raw materials: natural raw materials that are not suitable for food or animal feed, such as algae biomass, municipal and industrial waste, including by-products of the food industry.”
Although the technology for employing second and third-generation feedstock for bioplastics is still in development, KTU researchers are investigating one of these materials, which can be found in the inedible sections of many plants.
Dr. Ayodeji Amobonye, a KTU postdoctoral trainee from Nigeria working on the project “Development of bioactive and biodegradable bioplastics from sustainable polysaccharides,” stated that that nature inspired him to investigate the protective structures of various plants as potential sources of bioplastic components.
He stated, “This project, like many others, is inspired by nature, which encloses many of its fruits and seeds in ‘shells’ to protect them against unfavorable natural factors like humidity, UV rays, pathogens, and pests. Although the physical protection, for example in the nut shells, is mostly created by the lignocellulosic framework, it is, however, reinforced by various bioactive compounds. Hence, in developing new ways to produce functional bioplastics, we are exploring the potential of these natural compounds as key active agents.”
“Bio” Does Not Necessarily Stand for Biodegradable
Biodegradability is the main attribute of bioplastics that makes them increasingly appealing in a variety of industries, particularly because the unique chemical and physical qualities of biodegradable bioplastics may even beat conventional petroleum-based polymers.
“Biodegradable bioplastics, under certain environmental conditions, can fully decompose into natural materials such as water, carbon dioxide, or compost. In this case, no bioplastic particles remain, so neither soil nor water resources are contaminated,” added Dr Rutkaitė.
Bioplastics with more bioactivity, in turn, can have greater utility, such as aiding in the fight against food waste, which is another of the world’s most important issues.
“The antimicrobial and antioxidant properties of these functionalized bioplastics are relevant for the food packaging industry because they could prolong the shelf-life of packaged goods, which could also help reduce food waste,” further added Dr Amobonye.
However, it is crucial to note that the term “bio” does not imply that all bioplastics are biodegradable. Dr. Rutkaitė noted that some plant-based bioplastics might not be biodegradable, whereas some fossil-based plastics degrade quickly.
She added, “Biodegradability properties are more related to the chemical structure of the material rather than the source it is made from. Therefore, when recycling bioplastics, it is very important to look at the label on the bioplastic package. If it is labeled as home compostable, it can be composted in the household or thrown in the kitchen and food waste bin. On the other hand, if there is no such information, the bioplastic packaging should go into the plastic waste bin.”
Learning to Live with Plastics
Dr. Rutkaitė is certain that bioplastics won't be enough to save the globe. Although it can lessen the quantity of fossil fuels used in the plastics sector, humans must first learn how to manage the enormous volumes of synthetic plastics that are already damaging the environment. She noted that in recent years, recycling conventional plastics has taken precedence over the creation of novel bioplastics.
Dr Rutkaitė emphasized, “Synthetic plastics are not the reason our planet is polluted. Human is the polluter who is unable or sometimes even unaware of the need to collect and recycle plastics. Therefore, it is very important to improve the collection and sorting of plastic waste in all countries around the world, to reduce the use of single-use plastic products, to reuse them, and, above all, to raise consumer awareness, because, eventually, everyday behavior determines the level of consumption and collection of plastic products.”
However, ingrained consumer behavior is not the sole obstacle to a swift global shift to bioplastics. For the time being, synthetic plastics' affordability and robustness make them indispensable.
Furthermore, the infrastructure and technology needed to produce bioplastics from second- and third-generation feedstock are still in their infancy, and the price of current bioplastics is many times greater than that of traditional plastics. Consequently, both experts acknowledge that a swift worldwide shift to bioplastics is just not feasible.
Dr Amobonye concluded, “We must, however, keep in mind that Rome was not built in a day, and most of the everyday technologies that we use now were at some point exclusive and expensive. Thus, we need continuous research and developmental efforts in the bioplastics field, which would facilitate innovation and allow the industry to reach its full potential.”
He concluded, “Waste-to-energy recycling, as well as mechanical and chemical recycling schemes, are top of the approaches for addressing the plastic waste problem. All three approaches are also used in Lithuania; however, mechanical and chemical recycling rates, following the new EU Packaging and Packaging Waste Regulation, which is expected to take effect soon, will have to be increased.”