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Can corn, sugar cane and other starch-rich sources replace crude oil when making plastics? In many cases, yes, it is technically possible. But of course the question is more complex than that.
What is the difference between bioplastics and bio-based plastics?
The concept “bioplastics” raises issues as it suggests that the polymer is more environmentally friendly, and/or that it’s derived from biomass only. That’s why some advocate using the term “bio-based plastics” or “bio-based polymers” when referring to plastics derived from renewable biomass, including when they are mixed with petroleum-based plastics.
So bio-based plastics can also contain petro-based materials?
Yes, there is no official definition or international standard. Polymers that have somewhere between 10–100% bio-based content are usually referred to as bio-based plastics. They are most widely used for thermoplastics.
Do bio-based plastics have less environmental impacts than petroleum- based plastics?
Generally speaking, they have the benefit of being partly or fully derived from renewable resources. But to say more than that, each raw material must first undergo a life-cycle analysis. For example: if a rainforest in Brazil is cut down to farm sugar cane, which then is refined into ethanol and bio-based polyethylene in facilities run on coal power, and the materials are then transported to China to manufacture products that are transported to Europe, the negative environmental impact can be very large.
At end of life, are bio-based plastics also biodegradable or recyclable?
Not necessarily – some are, some are not. With regard to recyclability, the only bio-based plastic that is currently recycled on a larger scale is bio polyethylene (bio PE), which is primarily used in packaging. Bio-based plastics can also be used to produce energy at end of life, which can be positive if they thereby also replace fossil fuels.
Why do bio-based plastics still represent such a minor proportion of total production?
Bio-based plastics are still more expensive, and large investment is required to transform the plastic industry to become more circular and bio-based. If international demand begins to increase significantly, this development may go quickly.