# Effect of thermoplastic polyurethane filament on the cellular ceramics structures obtained from material extrusion and polymer-derived ceramic

## TL;DR

This study explores how different thermoplastic polyurethane filaments affect the creation of cellular ceramic structures through 3D printing and pyrolysis.

## Contribution

The novelty lies in comparing ester- and ether-based TPUs with a commercial TPU for ceramic structure fabrication.

## Key findings

- All TPUs successfully impregnated with polysilazane, resulting in dense ceramic struts after pyrolysis.
- Ninjaflex showed greater mass and volume increase after impregnation but similar pyrolysis outcomes.
- Ester- and ether-based TPUs had similar mass and volume increases with high deviation.

## Abstract

Cellular ceramic structures were fabricated via 3D printing of thermoplastic polyurethane (TPU) followed by impregnation with polysilazane, and pyrolysis. The 3D printing was performed using fused filament fabrication (FFF), while the ceramic was obtained through the polymer derived ceramic (PDC) process starting from a commercially available polysilazane, Durazane 1800. We investigated the role of ester- and ether-based TPUs with two different Shore hardness (90A vs 80A) on the impregnation of polysilazane. Regardless of the TPU type and Shore hardness, impregnation of the TPU 3D structure was successful and resulted in dense, non-hollow ceramic struts after pyrolysis. All polyester- and polyether-based TPUs showed a similar mass and volume increase after impregnation with high deviation. The mass loss during pyrolysis was also very similar for all the TPUs. The behavior of these TPUs was then compared with one commercial TPU filament (Ninjaflex with a Shore hardness of 85A). While the Ninjaflex 3D-printed structures showed a greater increase in mass and volume after impregnation, the pyrolysis outcome was almost identical to that of the samples fabricated with both ester- and ether-based TPUs, resulting in dense, non-hollow ceramic struts.

The online version contains supplementary material available at 10.1007/s40964-025-01243-w.