Plastics are incredibly useful materials with extremely diverse properties, allowing a multitude of different applications that benefit our lives. But, with marine plastic debris estimated to reach 250 million tonnes by 2025, governments across the globe are starting to think about how to overcome this significant problem.
The majority of plastics are made using oil-based materials, meaning that, by their chemical nature, many plastics have no oxygen content. This makes them very difficult for common bacteria to break them down if they enter the environment.
Over the past few decades, the concept of using bio-based materials as a resource rather than oil-based materials has gained momentum. These natural, bio-based materials can easily be broken down into smaller chemical building blocks – called “platform molecules” — which in turn, can be used to make other useful chemicals, including plastics. Using these platform molecules, the Green Chemistry Centre of Excellence at the University of York, has been working with the plastics industry to create a new generation of bio-based polyesters. These are often used to make fibres for clothing, as well as films and containers for liquids and foods. The resulting materials are entirely plant based, recyclable.
Aside from sustainability, the huge benefit of using biomass as a resource is the high quantity of oxygen that is incorporated into nature’s chemical structures (glucose etc). By using biobased materials to make biobased plastics, the oxygen content is kept in the material. The hope is that by having a high oxygen content, the bio-based plastics will have high, but controlled biodegradability. This means that this plastic can totally and safely break down into benign starting materials.