As the 3D printing industry continues to expand throughout the world, the environmental footprint that it leaves behind will play a critical role in the success of this emerging technology. That’s why a number of filament producers, such as Extrudr and BioInspiration, have dedicated their time and resources to manufacturing bioplastic materials that are biodegradable or compostable. Though the two terms might seem like they’d have similar definitions, there is a vast difference between biodegradable materials and compostable materials, though they both aim to protect the environment in the long run.

In terms of the 3D printing industry, these environmentally conscious filament producers are doing all that they can to keep the amount of waste generated from additive manufacturing to minimum. Still, many 3D printing users confuse the terms ”biodegradable” and ”compostable”, and we’re here to help settle the differences. To put it simply, biodegradable broadly means that an object can be biologically broken down, while the word compostable typically specifies that such a process will result in compost or humus, which is an organic component of soil formed by the decomposition of leaves and other plant matter.

What’s the Difference Between Biodegradable and Compostable Filaments?

The primary difference between biodegradable and compostable is the “humus,” which provides valuable nutrients to the soil and is 100% able to reintegrate with the natural cycle. Biodegradable product, on the other hand, simply disintegrate while in nature, disappearing without a trace. The disintegration of biodegradable materials could take anywhere from a week to years, while compostable items break down in a much more timely manner. In the case of Extrudr’s biodegradable plastic (BDP) filament line, their materials are composed of a unique bio-organic lignin, which is a complex organic polymer found on the cell walls of many plants.

“Our BDP filaments are generated from 100% renewable and pure natural resources. The material has a bio-organic composition based on lignin. As a result it blends for composting back into the natural cycle, as opposed to PLA which degrades only in bioreactors or certain laboratory conditions,” said Moritz Begle of Extrudr. “Therefore, our BDP filaments are CO2 neutral and ecologically absolutely harmless. The new biomaterials are a non-toxic alternative to conventional ABS, PETG or PLA filaments and even superior in heat resistance, hardness and elongation.”

As you can see, although the commonly used 3D printing material PLA is considered a biodegradable thermoplastic, it is only able to dissipate under certain environmental conditions. Produced in Berlin, Germany, BioInspiration’s WillowFlex is made from completely compostable raw materials, thus allowing it to return to and benefit nature. These BDP filaments produced by Extrudr or BioInspiration are actually able break down naturally and benefit the earth from which they were created.

“For BioInspiration, the impulse to develop our compostable filament came from having children. We experienced first hand how few toys were on the market that were truly environmentally aware. We wanted to put our energy into developing materials that we could put in their hands without a second thought,” Brian Crotty, the CEO of BioInspiration. “We took 3D Printing Filament as a prototype because we saw a similar gap. Most 3D Print users are melting plastic and dispersing micro-particles in the air in an unventilated space.”

All in all, biodegradable plastics decompose by the action of living organisms, usually bacteria, but that doesn’t necessarily mean that it will be cycled back into the earth. Compostable materials, however, will result in beneficial compost or humus and will also occur naturally, without the need for a bioreactor or other specified surroundings. Within the US and throughout Europe, the standard label to look at and know if a material is biodegradable or compostable is ASTM D6400 and EN 13432.