Polyvinylidene fluoride – Hydroxyapatite 0–3 biocomposite filaments processed by twin-screw extrusion

• Published in: Journal of the mechanical behavior of biomedical materials 2022-01, Vol.125, p.104891-104891, Article 104891
• Main Authors: Silva, L.E.J., Volnistem, E.A., Dias, G.S., Cótica, L.F., Santos, I.A., Fiorentin, E.R., de Oliveira, M.A., Witchemichen, D.H., Freitas, V.F., Bonadio, T.G.M.
• Format: Article
• Language: English
• Subjects: Biocomposites; Durapatite; FDM; Fluorocarbon Polymers; Hydroxyapatite; Polymers; Polyvinyls; Printing, Three-Dimensional; PVDF; TSE
• ISSN: 1751-6161; 1878-0180
• DOI: 10.1016/j.jmbbm.2021.104891

Polyvinylidene fluoride – hydroxyapatite composite filaments were processed by twin-screw extrusion at different processing angular velocities and characterized by scanning electron and atomic force microscopies, differential scanning calorimetry and tensile tests. Polymer-ceramic composites with a 0–3 connectivity were successfully obtained. Regardless of the used processing parameters, all composite filaments present very similar melting (∼152°C) and solidification (∼139°C) points and elastic moduli (∼1.0 GPa) for hydroxyapatite as dispersed phase in the composite with concentrations up to 25 wt%, indicating that they are adequate for twin-screw extrusion and 3D printing. However, the yield strength (∼29 MPa), ultimate tensile strength (∼36 MPa) and tensile point (∼29 MPa) parameters are similar only for hydroxyapatite concentrations up to 15 wt%, once higher concentrations of hydroxyapatite as dispersed phase result in fragile samples (∼50% lower for each studied property). •Polyvinylidene fluoride – hydroxyapatite composite filaments successfully processed by twin-screw extrusion.•All filaments are adequate for to be used in additive manufacturing applications in fusing deposition modeling approaches.•The filaments show similar melting (∼152 °C) and solidification temperatures (∼139 °C), elastic moduli (~1 GPa).