Degradation Properties of Magnesium-Polycaprolactone Composite by Fused Extrusion Additive Manufacturing Process

As bone repairation biomaterial, polycaprolactone has disadvantages of poor mechanical properties, long degradation time, hydrophobic surface and poor osteoinductive property. Mg micro-particles were incorporated into the PCL matrix to produce Mg/PCL composite materials and fused extrusion additive manufacture technology was used to fabricate bone repair porous scaffolds. By the vitro degradation experiment, from the pH of the degradation solutions, the result shows that the pH of Mg / PCL increases and the pH of pure PCL decreases, which indicates the degradation of the composite and alkaline substances were produced. From the crystallinity and compressive strength test results, it can be seen that the addition of Mg particles reduces the crystallinity and compressive strength of pure PCL. By observing the micro morphologies of porous scaffolds, Mg particles attached to the surface of Mg / PCL porous scaffolds gradually fall off with the increase of degradation time, and more obvious degradation cracks are formed on the surface of scaffolds. The molecular weight of the two materials after degradation was measured. The molecular weight of Mg/PCL composite decreases more obviously. The results show that the addition of Mg particles accelerates the degradation rate of PCL, and the Mg ions produced by degradation promote the repair of bone defects. The experimental results show that compared with other biomaterials, changing the content of Mg in composite implants can regulate the degradation rate of PCL and match the degradation process with the bone regeneration process, which has good application prospects in the field of osteochondral. © 2021, Editorial Board of Polymer Materials Science & Engineering. All right reserved.