There are two main reasons to replace general purpose plastics: to reduce plastic waste and the use of fossil raw materials – mainly oil, but increasingly coal and shale gas. It’s not just the greenhouse gases that matter: the production and use of such products are important parts of our total footprint. Cellulose offers an interesting alternative, but it is not a magical cure for all our problems.
Plastic is not unequivocally evil – it makes our world safer and more efficient. For example, plastics help us to reduce food waste, improve food safety, and facilitate water supply. Their workability and low price are great advantages to plastic materials.
Cellulose as an alternative
Biomaterials, such as cellulose, offer a potential alternative to plastics – for example, in packaging and the textile industry. The production volume of cellulose is similar to plastics, making it a realistic choice. It would take decades before other alternatives that are currently under development could compete in these volumes.
Biomaterials have some clear advantages when compared to plastics. They are made of renewable raw materials, and by utilizing a short carbon cycle, we can reduce or even eliminate the use of fossil carbon stocks. Biomaterial products bind carbon, which constrains the amount of carbon dioxide in the atmosphere. That said, the growing use of cellulose causes concern about the decreasing carbon stock in our forests. The challenge, however, is more about how efficient production might reduce biodiversity.
Biodegradability is another advantage related to biomaterials, although all bio-based materials are not biodegradable. Recyclability is becoming increasingly important for plastics and other materials, especially in the EU. The recyclability of cellulose, especially fiber cellulose, is very promising for future solutions.
Improving performance and sustainability
The efficiency and performance of materials have always driven development. Replacing traditional materials is increasingly promising when the alternatives improve performance. New materials can enable genuinely better, more functional, efficient, and economic solutions. The inherent properties of cellulose – such as stiffness, transparency, or workability – provide special opportunities for improved performance.
Today, performance must also include sustainability, which is a result of many factors – environmental friendliness of raw materials and production, efficiency of the products, and handling the used material, for example. We must find a balance between these factors and choose the best option for each application.
Tackling new challenges
The development of new materials may also lead to discovering new and unexpected application areas. Our society is changing, which brings up new challenges like how to guarantee a secure environment and pure food, water, and even air for a growing population, all while our environment is changing and nature is perishing at a rate we have never seen before.
We cannot tackle all these challenges solely with solutions based on materials. Still, materials can be something more than just a bandage for our planet. When we talk about new solutions, it is crucial to develop not just the materials but also product development and systems for handling these products.
The move to replace plastics with cellulose depends on the overall efficiency. The importance of recyclability is increasing, but we can’t forget about the parallel use of plastics and cellulose.
Ali Harlin Research Professor in Biomass Processing and Products at VTT