"We are very close to introducing a fully ecological biodegradable bioplastics into industrial production," explained Professor Pavol Alexy of the Slovak University of Technology, Faculty of Chemical and Food Technology in the “Reports and Comments” TV program.
What is the difference between ordinaryplastics and bioplastics?
Basically, the term "ordinary plastics" refers to the plastics made from fossil sources, such as oil, and they generally do not degrade in nature. The term bioplastics is no so unambiguous. Currently, three types of bioplastics are on the market:
- There are bioplastics made of renewable raw materials, not subject to biodegradation, such as polyethylene. They can be made either of petroleum or starch and used for making shopping bags. It lasts several hundred years until they decompose in nature, just like any synthetic polyethylene. However, microplastics will remain even after its desintegration.
- Another type of bioplastics is made of crude oil; it is biodegradable, so it can decompose in nature, or in compost. However, the gases emerging during decomposition are actually greenhouse gases, so that it cannot be considered truly ecological bioplastics.
- True organic is a biodegradable bioplastic material made of renewable sources. This is the only fully eco-friendly solution ensuring that plastics will turn to a biomass again, and the gases emerging during decomposition will not produce a greenhouse effect.
Why is the utilisation of bioplastics still limited?
On the one hand, they are more expensive and will always be a little more expensive than ordinary plastics, besides, exhibiting some technical shortcomings, they did not meet the required mechanical properties so far, e.g. they were too brittle. This is currently being treated by adding synthetic plastics, which reduces their ecological value. The problem has been basically solved now; wider application is just a matter of money and possibly logistics. We should realize that rather than ending up in the ocean, the bioplastics also must be separated and disposed properly, i.e. valorised by composting, just like synthetic plastics by recycling.
What are the future applications of bioplastics?
There are wide options. Perhaps the segment of packaging materials, which accounts for about 40-50 per cent of all plastic waste, will bring the biggest benefit. That is where the primary application of those truly ecological bioplastics should be oriented. Other fields of technical applications definitely involve medicine, tissue engineering in particular, where bioplastics are used in regenerative medicine. A wide range of possibilities is being opened up.
Alarming photos and videos of oceans full of plastics are widely known. Can bioplastics completely decompose into harmless substances in the sea water in future?
There is a type of bioplastics produced by microorganisms themselves and they are degradable in the sea water. I can say that we are very close to developing such a plastic material. Fully biodegradable ecoplastics already exist in principle, they can even be (or will be soon) produced. However, this must not deprive us of the obligation to separate and sort these materials, instead of just throwing them away.
At the same time, giving people plastics that will decompose in sea water must not lead to increasing the supply of "fresh" bioplastics to the ocean. If the supply exceeded the amount than the ocean can consume and decompose, we will get back where we were right now.
Source: Správy a komentáre, RTVS Dvojka, 12. 6. 2019
Illustratives Foto:The National Oceanic and Atmospheric Administration (Ben Mierement)