Enhancing mechanical performance of solvent-cast 3D printed PCL composites: A comprehensive optimization approach

This study aims to enhance the mechanical properties of 3D-printed scaffolds by optimizing a composite of Poly-ε-caprolactone (PCL), poly-hydroxybutyrate (PHB), and synthetic fluorapatite (FHAp) using Response Surface Methodology (RSM). The research targets the intricate relationships between PCL, PHB, and FHAp concentrations, crucial for achieving optimal tensile, compressive, and flexural strengths. The solvent-cast process successfully yielded FHAp-reinforced PCL composites, confirmed by XRD and FTIR spectra. The findings indicate that an optimal PHB content of over 15 % wt/v and PCL under 10 % wt/v significantly enhance tensile strength, achieving values up to 48 MPa. Compressive strength peaked at PHB concentrations of 13–16 % wt/v and PCL concentrations of 9–13 % wt/v, showcasing effective stress transmission, with the highest recorded value being 90 MPa. Flexural strength exceeded 100 MPa with lower concentrations of PCL and PHB, emphasizing the need for a balance of rigidity and flexibility. The study identifies the optimum composition for these mechanical properties at PCL 9.432 % wt/v, PHB 16.568 % wt/v, and FHAp 24.933 % wt/v, crucial for advanced biomedical implant applications.