How do the printing parameters of fused filament fabrication and structural voids influence the degradation of biodegradable devices?
journal contributionposted on 2021-10-06, 08:58 authored by Feng Chen, Alper Ekinci, Ling Li, Meng Cheng, Andrew JohnsonAndrew Johnson, Andy GleadallAndy Gleadall, Xiaoxiao Han
Fused Filament Fabrication (FFF), a commonly used additive manufacturing technology, is now employed widely in biomedical fields for fabricating geometrically complex biodegradable devices. Structural voids arising from the printing process exist within the objects manufactured by FFF. This paper reveals the underlying mechanism of how the printing parameters and voids affect the degradation behaviours of devices made of biodegradable polyesters. It was found that both voids and internal architecture (layer height, for instance) affect the degradation rate by interacting with the reaction-diffusion process. Large suppression of the degradation rate was found when auto-catalytic hydrolysis and diffusion are significant. Degradation rate reduced in an approximately logarithmic manner as void size increased. The extent this effect depended on the strength of auto-catalytic hydrolysis and diffusion, void size and overall device size. The internal architecture of FFF products (regulated by printing parameters) influences the degradation rate by altering the diffusion speed of acid catalysts (regulated by diffusion path length). Both void size and internal architecture should be considered in fabricating biodegradable devices using FFF.
National Natural Science Foundation of China (52075158)
Key R&D Program of Hunan Province (2020SK2093)
Innovative Platform and Talents Program of Hunan Province (2019RS1019)
- Mechanical, Electrical and Manufacturing Engineering