When is a plastic biodegradable?
Bioplastics can have a biobased content, be biodegradable or biocompatible. But what does "biodegradable" actually mean?
Plastic is a mixture of different materials that produce a moldable solid. When decomposition occurs through biological activity, a material may call itself biodegradable. If enough oxygen is available for the microbes, fully biodegradable materials leave behind nothing but CO2, water, minerals and biomass. Above all, no microplastic particles!
How long does this take?
The term "biodegradable" says nothing about how long this process can take, as the duration depends greatly on the environmental conditions. Is it on land or underwater? How warm is it? Is there enough moisture? Are the right bacteria or fungi present? Therefore, your product made from our BIOVOX materials will not simply decompose while you are using it.
A compost pile heats itself up because of all the bacteria digesting the biomass. It can reach temperatures up to 60°C or 140°F.
The time frame
To solve the timeframe and conditions issue, the term compostable comes into play. This term is exactly defined by normative institutes in Europe and the US. Easiest to define is the “industrial composting”. For a material to pass this test, it needs to lose at least 90% of its weight within 90 days in an industrial composting environment, which is set at about 58°C or 136°F.
“Home compostable” is a bit trickier. The bacteria and other microbes responsible for biodegrading, like it moist and warm. If temperatures drop, they will slow down. You use this tactic everyday with your refrigerator. For a material to pass the “home compostable test”, it therefore has 12 months at ambient temperatures of 20-30°C to lose 90% of its biodegradable weight.
But keep in mind that your climate zones and other circumstances will heavily impact the duration if you try it at home. For example, if the ground is frozen during winter, most biological processes are nearly stopped. On the other hand, if you live in a hot humid climate, biodegradation will be faster. Additionally, the thickness and structure of the material also plays a huge role: the thinner the faster. As a rule of thumb, composting biodegradable plastic products is similar to a comparable product made out of wood.
To learn about the biodegradability of a product or material, look for these certificates:
In a Nutshell
When decomposition occurs through biological activity, a material may call itself biodegradable. They leave behind nothing but CO2, water, minerals and biomass. The duration of the process depends greatly on the environment. As a rule of thumb, biodegradable plastic products compost at a similar rate as a comparable product made of wood.
More BIOVOX knowledge
Your products are made from bioplastics now – great, but how do you communicate this switch to your target group? In this article, we explain how to communicate sustainability authentically.
Which plastics can be safely used in medical technology to manufacture medical and pharmaceutical products or packaging? This and the term “Medical Grade Plastics” are explained in this short article.
Eine Sterilbarriereverpackung aus Kunststoff sorgt dafür, dass Medizinprodukte wie Kanülen oder chirurgische Instrumente lange Zeit keimfrei bleiben. Nur so können sie sicher verwendet werden. Was Sterilität ist, warum wir sie brauchen und ob sich Biokunststoffe als Sterilbarriere eignen, das hat BIOVOX-Expertin Maria Heckel in diesem Artikel zusammengefasst.