I’m going to refer to a study called Fabricating Strong and Stiff Bio Plastics from Whole Spirulina Cells. To me, that sounded a bit daunting but the study is very important and the scientists start off with the shocking introduction: “Since the 1950s, 8.3 billion tonnes (Bt) of virgin plastics have been produced, of which around 5 Bt have accumulated as waste in oceans.”
Five billion tonnes of plastic discharged into the oceans. There’s obviously a lot more plastic on dry land as well. So, there is a great and pressing need to find alternatives to petroleum-based plastic. What this means is sustainable bio-based alternatives.
This has been a sort of holy grail of the scientists but there are complications because alternatives can have “weak mechanical properties and [a] lack of processability”. In other words, it’s not strong enough and it is difficult to manufacture in large quantities.
But the scientists have come up with an alternative using powdered blue-green cyanobacteria cells, otherwise known as spirulina.
They apply heat and pressure which is similar to the way ordinary plastic is made and the resultant harden powder can be formed into different shapes.
It is a form of eco-plastic and has been created by the team at the University of Washington which has mechanical properties comparable to single use, petroleum-produced plastics according to the scientists.
In their words, in the summary of their study, they say:
Here, a fast, simple, and scalable process is presented to transform raw microalgae into a self-bonded, recyclable, and backyard-compostable bioplastic with attractive mechanical properties surpassing those of other biobased plastics such as thermoplastic starch.The research team at Washington University.
They add that the algae is abundant and that the resultant alternative form of plastic has a “flexural modulus and strength in the range 3–5 GPa and 25.5–57 MPa, respectively, depending on pre-processing conditions and the addition of nanofillers.”
I have some articles about plastic pollution of the oceans which are referred to below which you can read about if you wish.
Link to the study: https://doi.org/10.1002/adfm.202302067