Can 3D Printed Waste be Recycled?

Understanding Plastic Recycling

Plastics can be split into three main subsets Thermoplastics, Thermoset plastics and Elastomers. Thermoset plastics often require a curing process during which the polymers become cross-linked together and form an irreversible chemical bond.  As a result of the cross-linking process the polymers are unable to be re-melted or re-moulded. This makes them ideal for high temperature applications. However, as thermoset plastics cannot be re-melted they are unable to be recycled. Resin based 3D printers such as the SLA process use thermoset plastics.

Thermoplastics do not need to undergo a curing process. Subsequently, this means the polymers are able to be re-melted and recycled. Thermoplastics are extensively used in FFF/FDM printers so in theory most prints can be recycled however this is not always the case. Different thermoplastics are easier to recycle than others. As a result not all recycling plants are able to recycle the same materials. The types of materials that can be processed by recycling plants can vary across the country and across the world.

Elastomers aren’t commonly used for 3D printing, however thermoplastic Elastomers such as TPE and TPU are used for creating flexible materials. However, like Thermoset plastics these aren’t able to be recycled as the elastic properties are similar to thermoset plastics.

So Can 3D Printed Parts Be Recycled?

PLA, ABS, Nylon and Polycarbonate are all common types of FFF/FDM filament, all of which are thermoplastics.

Thermoplastics are not commonly accepted by most recycling centres. They are all classified as a Type7 plastics which means you’re not able to put them into a recycling bin.

PETG can be recycled by some recycling centres, however it isn’t commonly accepted. It has similar chemical properties to PETE (which is widely recycled), which makes it difficult to differentiate between them. If the plastics get mixed during the recycling process it can dangerously affect the temperature stability of the recycled PETE.

Whilst PLA isn’t widely recycled, PLA does have one unique property: It is plant based. It can be referred to as a bioplastic. Whilst it is biodegradable it does still take a very long time to decompose and is extremely dependent on the conditions.

How Can I Be More Sustainable?

Although most local recycling centres are unable to recycle your 3D printed parts there are a number of other ways to be more sustainable.

Firstly designing parts intelligently to avoid printing unnecessary material and support can be a great way to reduce waste material. Always ensure you check the first couple of layers of a print to ensure it is adhering to the bed. If the print isn’t adhering to the bed then the print will more than likely fail and cause more waste material. It is also important to ensure the printer is regularly maintained so that it prints more reliably and again leads to less waste.

One way is to invest in a filament extruder. This is where you can use your waste material and can re-melt the plastic down and extrude back into filament. This process isn’t ideal for everyone and is generally used by hobbyists. It can be a time-consuming process having to grind down the waste plastic into pellets to be re-melted. However, it can help to reduce waste and cut down on filament costs.

As recycling your own filament using a filament extruder can be expensive to set up and time-consuming another alternative to be more sustainable is to use recycled filaments that have already been processed. This cuts out a lot of the cost and hard work to do it yourself. Companies such as Filamentive recycle both post-consumer waste and post-industrial waste to produce their filaments. This means they are not only sustainable but also have great mechanical properties as well.

You can see the Filamentive Filaments here. If we can be of any help regarding your choice of filament or 3D printer, please get in touch: 01926 333 777 or info@solidprint3d.co.uk