Concordia recycles PEKK with lunar regolith for 3D printing

(SpaceEnergy) Concordia University researchers have demonstrated a closed-loop additive-manufacturing process combining recycled space-grade PEKK thermoplastic with lunar regolith simulant to produce components for potential future lunar infrastructure.

The researchers recycled poly(ether ketone ketone), or PEKK, from a previously printed component, mixed it with commercially available lunar regolith simulant and converted the composite into filament for 3D printing.

They produced test specimens, a wrench and sacrificial structures designed to absorb energy by deforming under load, potentially including loads comparable with those experienced by lunar-lander mechanisms during touchdown.

Testing found that the recycled PEKK retained its thermal and mechanical properties through three recycling cycles without significant degradation.

Adding regolith simulant reduced shrinkage and warping during heat treatment and lowered the temperature at which PEKK crystallised, potentially reducing processing requirements for off-Earth manufacturing.

The composite nevertheless exhibited greater internal porosity than unmixed PEKK and was more brittle, indicating limitations requiring further development.

Professor Mehdi Hojjati of Concordia's Department of Mechanical, Industrial and Aerospace Engineering said the study was among the first to demonstrate a closed-loop approach combining recycling of a high-performance space-grade polymer with lunar regolith.

The work used simulated rather than actual lunar material and remains an early-stage laboratory demonstration.