Materials News
Meeting of the minds for bioplastics Industry think tanks led by researchers and scientists are advancing bioplastics and weighing in on their pros and cons, says Angelica Buan in this report.
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he creation of early bioplastics from cellulose, milk and bacteria has paved the way to providing solutions to today’s more complex global issues, such as climate change and marine litter due to rising volumes of non-degradable plastic waste. Researchers and scientists are instrumental to advancing bioplastics technology. There is, after all, an avalanche of resources that can be harnessed to create bioplastics. But there is a caveat, according to some experts: the raw material used as feedstock may outweigh the benefits of producing and utilising bioplastics at an industrial scale. The solution anchors to staying within the circular economy schema to cultivate sustainability; and by using waste as bioplastic raw material is one way to achieving this. Green claims through the lens Recently, bioplastics’ carbon neutral claim has been scrutinised, thus somewhat undermining its sustainability worthiness. A recent study from the University of Bonn suggests that shifting to plant-based plastics may not be as environmentally sustainable after all, for the reason that the more bioplastics are consumed, the greater greenhouse gas emissions are generated from cropland expansion. Notwithstanding the amount of water needed to cultivate crops utilised for the feedstock. Dr Neus Escobar, from the University of Bonn’s Institute of Food and Resource Economics, said that large scale production of bioplastics would change land use globally, and thus could potentially lead to an increase in the conversion of forest areas to arable land. He said that ramping up demand for so called green energy sources is a cause of massive deforestation in some countries across the tropics. Escobar also suggested that consuming bioplastics from food crops in greater amounts does not seem to be an effective strategy to protect the climate, as this would trigger many other negative effects, such as rising food costs. Nevertheless, he stressed that using crop residues and food wastes for producing bioplastics rather than crop feedstock would have a more favourable result. He also debunked the narrative that plant-based plastics are easily degradable in marine environments and thus will contribute in reducing the amount of wastes in the oceans. “Bio-PE and Bio-PET are for example not biodegradable, same as their petroleum-based counterparts,” he pointed out.
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MAY 2019
The study, published in the Environmental Research Letters journal, does not negate, however, the fact that bioplastics are, “in principle, climate-neutral, because they are based on renewable raw materials such as maize, wheat or sugar cane”. It said that these plants get the carbon dioxide that they need from the air through their leaves. Thus, producing bioplastics consumes carbon dioxide, which compensates for the amount that is later released at end-of-life. Overall, their net greenhouse gas balance is assumed to be zero. Tuning up bioplastics for broader applications The bioplastics market has huge potential. Allied Market Research estimated the market to cross US$68.5 billion by 2024, the period that is targeted by a number of companies such as shoe maker Adidas; and economies like the European Union (EU) to increase use of recycled plastics, while cutting down use of fossil-based plastics. But currently, the bioplastics market is impeded by higher cost of production and lower performance compared to synthetic plastics. Likewise, bioplastics have limited applications due to their low biostability.
Adidas has made a shoe from a version of thermoplastic polyurethane (TPU), which is 100% recyclable and also zero waste. It does this by taking the first generation shoe back, recycling that and using the recycled material to create components for a subsequent shoe