Biodegradable and recyclable bioplastic made of banana waste
Researchers at UNSW Sidney developed a method to turn banana plantation waste into a biodegradable and recyclable packaging material.
The production of bananas generates relatively large amounts of waste, as only 12 per cent of the plant, namely the fruit, is used. The rest is commonly discarded as the plant dies after each harvest.
The researchers were specifically interested in the pseudostems, which is the layered, fleshy trunk of the plant. These stems are sometimes used in textiles or paper, but mostly discarded.
The pseudostems consists of about 90 per cent water. The researchers cut up the stems and let them dry at very low temperatures in a drying over. The remaining 10 per cent of the material is milled into a very fine powder. In turn, this powder is washed with a very soft chemical treatment, isolating nanocellulose.
While nanocellulose can be retrieved from any plant, banana plants are a good choice because the nanocellulose is high quality, and as banana plants are annual, there is plenty agricultural waste available.
When processed, the material has a consistency similar to baking paper. Depending on the thickness, it could be used in food packaging or to make bioplastic bags. Film made of the material breaks down organically in soil within 6 months. Additionally, the material is recyclable without change in its properties.
Photos: UNSW Sidney / Pixabay