关键词: Nano-biocomposite, Polycaprolactone, Fluorapatite, Bone tissue engineering, Mechanical properties

Abstract: In this study, nano-biocomposites of polycaprolactone (PCL) as the matrix and diferent amounts of nanofuorapatite (nFA) (0, 10, 20 and 30 wt.%) as the reinforcement were prepared for possible scafold fabrication using the fused flament fabrication (FFF) 3D printer. Field Emission Scanning Electron Microscopy (FE-SEM) and Energy Dispersive Spectroscopy (EDS) showed that nFA particles were well distributed in the PCL matrix. X-ray difraction analysis (XRD) and Fourier Transform Infrared Spectroscopy (FTIR) depicted no chemical interaction between the elements of the composite. Diferential Scanning Calorimetric (DSC) analysis was then used to assess the thermal properties of the composites, suggesting that this could be due to the amorphous phase formation of the intermolecular hydrogen bonds between PCL and nFA, resulting in the suppression of PCL crystallization. The results of mechanical characterization also showed that the addition of nFA up to 20 wt.% to the PCL increased the tensile and yield strength, as well as reducing the elongation at both yield and failure points and increasing the Young modulus. The best mechanical properties were obtained for the PCL/20nFA composite. Tensile strength and Young modulus were increased by 30% and 179%, respectively; meanwhile, elongation of PCL/20nFA was decreased by 70%, as compared to the naked PCL. These changes could be attributed to the better distribution of the nFA fller in the PCL matrix. According to the obtained results, PCL/20nFA could be regarded as a good composite in terms of the mechanical properties for the regeneration of the bone tissue.

Key words: Nano-biocomposite, Polycaprolactone, Fluorapatite, Bone tissue engineering, Mechanical properties