The orthotropic viscoelastic characterisation of sub-zero 3D-printed poly(vinyl alcohol) cryogel

J P Crolla; M M Britton; D M Espino; L E J Thomas-Seale

doi:10.1557/s43580-021-00086-1

The orthotropic viscoelastic characterisation of sub-zero 3D-printed poly(vinyl alcohol) cryogel

MRS Adv. 2021;6(18):467-471. doi: 10.1557/s43580-021-00086-1. Epub 2021 Jun 22.

Authors

J P Crolla¹, M M Britton², D M Espino¹, L E J Thomas-Seale¹

Affiliations

¹ Dept. of Mechanical Engineering, University of Birmingham, Birmingham, B15 2TT UK.
² School of Chemistry, University of Birmingham, Birmingham, B15 2TT UK.

Abstract

Abstract: Poly(vinyl alcohol) cryogel (PVA) is a versatile biomaterial used to replicate the biomechanics of tissues. Additive manufacture (AM) at sub-zero (°C) temperatures enables the manufacture of PVA with complex geometry; however, the effect of processing parameters on the mechanical properties of PVA has not been evaluated. The aim of this study is to understand the impact of print nozzle diameter and orientation on the viscoelastic mechanical properties of PVA. Samples of sub-zero AM PVA, with different filament thicknesses, were tested under tension relative to the print direction, to calculate the storage and loss moduli. As the nozzle size was decreased, AM PVA exhibited more pronounced orthotropic properties; the smallest size showed a 33% decrease in storage moduli when tested perpendicular to the print direction, as opposed to parallel. This study has demonstrated the ability of sub-zero AM to tailor the orthotropic properties of PVA.

Supplementary information: The online version contains supplementary material available at 10.1557/s43580-021-00086-1.

Keywords: 3D printing; Additive manufacturing; Polymer.