On biodegradability of 3D printed polyvinylidene fluoride composites

Abstract

Polyvinylidene fluoride (PVDF) is one of the established biocompatible thermoplastics for scaffolding applications. But due to its partial biodegradability, its use as a bio-absorbable implant is limited. Some studies have outlined that reinforcement of hydroxyapatite (HAp), and chitosan (CS) helps in improving the biodegradability of the PVDF composite matrix. But hitherto little has been reported on the biodegradability comparison for virgin PVDF, and PVDF composite matrix (with different proportions of HAp and CS as reinforcement). This study reports the biodegradability of virgin PVDF, 90% PVDF–10% HAp, 90% PVDF–8% HAp–2% CS, and 90% PVDF–9% HAp–1% CS based on a corrosion testing (open circuit potential, polarization resistance, corrosion current, corrosion rate [CR], surface roughness (Ra), and porosity %) in simulated bodily fluid (SBF) for possible bio-absorbable implant applications. The study suggests that the biodegradability of 90% PVDF–9% HAp–1% CS is maximum having CR 26.389mm2/year, mainly due to the presence of more hydroxyl group (-OH). The corresponding porosity % and Ra (after corrosion testing) were noticed as 12.45% and 19.12 µm. The results are supported by scanning electron microscopy (SEM) images.