In 2019, we launched the DURAPRINT project to innovate new approaches to tackling our world’s plastic crisis. Together with leading recycling partners Indorama, Ioniqa, and Corbion, we have been looking at how we can move beyond traditional plastic recycling to fully circular methods and bio-based material alternatives.

The project brings together two approaches. The first is focused on developing PEF, a bio-based recyclable plastic made from plant based sugars. Working with the Dutch food and biochemicals company Corbion, we are exploring the full lifecycle of this material and the potential it holds as an alternative to PET plastic.

We’re excited to share more news on the progress of the project. For more background information please see our previous blog on Duraprint here

PEF- First test extrusion of PEF

PEF is a bio alternative to PET and is made by microorganisms that use sugars derived from plants (and in the future from organic waste) to create a polymer building block called FDCA. In the polymerization stage, this FDCA is transformed into PEF, a bioplastic with comparable, and in some use cases better characteristics than fossil fuel-based PET.

Reflow completed the lab-scale extrusion for PEF filament, with granulates produced by Corbion. With the temperature ranges between 200 and 235 ºC. The initial lab-scale extrusion was highly successful.

Step 1PEF is added to the lab-scale extrusion

Step 2PEF is extruded on a small nozzle and air-cooled

Step 3PEF filament is spooled and ready for test printing

As a follow-up, 3D print tests were done and an initial 3D printing profile was established.

  • Nozzle 230 degrees Celcius
  • Bed 60 degrees Celcius
  • Print speed 30-50mm/s
  • Cooling fan 30%-100%
  • Retraction speed 35-45mm/s

The 3D prints came out with great layer adhesion, and with printing properties and settings very similar to the popular rPETG in the market. 

Due to the ease of print we expect the material to be easily extrudable and a viable product as a 3D print material. Mechanical tests will be performed on a further array of 3D print tests to check for delamination and mechanical strength compared to other 3D print materials. Full-scale extrusion will also be done in Q4 2021 to combat filament inconsistency (due to the lab-scale equipment) and create higher volumes of materials for test printing.

cPET – Full scale testing

Reflow has performed extrusion tests on the full-scale extruder with the supply of cPET provided by Indorama. As a first step, the cPET was dried in a desiccant drier at 160 ºC for 8 hours. After drying, the moisture content in the pellets was 0.046%, which was below the general guideline level of 0.2% for PET material extrusion.

After drying the materials were loaded into the hopper of the extruder. Extrusion temperatures were set according to technical suggestions from Indorama. The final temperature profile from the material feeding zone to the extrusion die (5 heating zones) was: 210, 265, 295, 283, and 270 ºC

Extrusion was stable so that the final 3D printing filament had consistent diameter and circularity. 

Additional analysis on diameter consistency and quality control will be done in Q4 2021

Next Steps

The follow-up tests for the project include

  • Full extrusion testing of the PEF
  • Mechanical and thermal testing of cPET
  • In-depth 3D print testing for PEF to distinguish printing properties
  • Larger product prints and modelling for communicating on the project

Over the next few weeks, we’ll release our interview with Jeroen Bulk from Ioniqa on the state and next steps of chemical recycling. Stay tuned!

Collaboration is key

The project – coined “DURAPRINT” – is done together with Indorama, the world’s largest PET producer and Corbion, a world leader in the production of bio-based materials. By combining leading players in plastic manufacturing with our sustainable approach to 3D printing, we can make the future of 3D printing truly sustainable and pave the way for these technologies to be implemented by a wide variety of industries.

This programme is supported by the European Union, KansenvoorWest subsidy.


Founder & CEO
Papa Reflow. Loving father of two, Serial RomCommer and climber