Photographer:Fotograaf: Joey Roberts
You don't have to search for very long online to find the effects of ocean garbage patches. The Internet is full of images of turtles with six-pack rings around their shells, seals covered in ribbons of discarded plastic bags, and beaches littered with plastic bottles. Bioplastics – currently only 2 per cent of all plastics – seem like the logical solution. If the material comes from nature, then it won't be damaging to it. But that is too simplistic, says Yvonne van der Meer, university lecturer of Sustainability of Bio-based Materials.
“Bioplastics are made from natural materials, but they are often processed. The substances that are added to them could be harmful. The aim is to make a more sustainable form of plastic, in order to combat climate change, not necessarily to make plastics more biodegradable. Some already are, but most of them are not – you cannot solve all problems in one go. You also want products with a long life. This makes it difficult to make the product biodegradable as well, as the two concepts are in conflict with one another. You could do it with a specific trigger that only decomposes the product when it is desired and not sooner.”
The question is if you should even want plastics to be biodegradable. “If they break down into increasingly smaller pieces until you can’t see them anymore, you are left with micro-plastics. What the exact effects of those are, we don't know yet, but you do see that micro-plastics turn up in fish and other marine animals. Decomposition must be fast and complete. In order to solve the existing problem, we need to invent a technology that can detect and remove plastic particles. Besides that, we don't know if biodegradable plastics dissolve completely in the ocean. This process often only takes place under specific circumstances, for example, at sixty degrees.”
According to Van der Meer, you can go two ways with bioplastics. Either you make them biodegradable. “Then you would only want to be left with CO2 and water, no harmful additions.” Or you recycle it. “In that case, the challenge would be to make high-quality new products from it. At the moment, recycled plastic is used for specific products, such as roadside poles or fleece jumpers. That is great, but the market will become saturated at a certain stage. So we have to make sure that more products can be made from it and preferably time and again. So not just going from high-quality products to low-quality products to nothing.”
It is also important to look at what people need to do to recycle plastics. “I recently saw sports shoes that were made from a plastic that dissolves when you place them in a certain type of solution. You are only left with the sole. But who is going to do that? Or take plastics that can be composted. You can dispose of those along with your organic waste, but people can't see the difference between bioplastics and ordinary plastics.” The result is that the waste stream gets polluted.
Another aspect is the energy source that is used to make the product. “If you use fossil fuels, you still have CO2 emissions. I sometimes ask students to compare figures. Sometimes it turns out that a certain type of bioplastic is more polluting than ordinary plastic. Then they think that I switched the data. But the oil-based plastics industry is completely optimised and extremely efficient, and therefore difficult to beat.”
In short, it is important to look at the entire life cycle of a product. “And that we realise that organic is not the solution for everything. Take the cutting down of rain forests for organic crops. That is completely unsustainable. This is what attracted me to this research, to see what is possible.”
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