# Multiscale Porous Poly (Ether-Ether-Ketone) Structures Manufactured by Powder Bed Fusion Process

## TL;DR

This study creates highly porous PEEK structures using a salt leaching method and powder bed fusion, maintaining good mechanical strength for applications like tissue engineering and drug release.

## Contribution

A novel method combining powder bed fusion and salt leaching to produce multiscale porous PEEK structures with high porosity and mechanical performance.

## Key findings

- PEEK structures with 79–86% porosity and 4.1 MPa compressive yield strength were achieved using 70 wt% salt.
- Structural integrity was maintained without drastically reducing process parameters due to salt leaching.
- Performance is influenced by printing orientation, coalescence, and pore/cell wall thickness.

## Abstract

The aim of the study is to create a multiscale highly porous poly (ether-ether-ketone) (PEEK) structure while maintaining mechanical performance; the distribution of pores being generated by the manufacturing process combined with a porogen leaching operation. Salt at 70 wt% concentration was used as a porogen in a dry blend with PEEK powder sintered in the powder bed fusion process. The printed porous PEEK structures were examined and evaluated by scanning electron microscopy, microcomputed tomography, and mechanical testing. The PEEK structures incorporating 70 wt% salt achieved 79–86% porosity, a compressive yield strength of 4.1 MPa, and a yield strain of ∼60%. Due to the salt leaching process, the PEEK porous frameworks were fabricated without the need to drastically reduce the process parameters (defined by the energy density [ED]), hence maintaining the structural integrity and good mechanical performance. The compression results highlighted that the performance is influenced by the printing orientation, level of the PEEK particle coalescence (controlled here by the ED), pore/cell wall thickness, and subsequently, the overall porosity framework. The porous printed PEEK structures could find potential uses in a wide range of applications from tissue engineering, filtration and separation to catalysts, drug release, and gas storage.