Material PropertiesManufacturing of PCL/SAg tubes by melt-extrusion for nerve regeneration: Structure and mechanical properties

The incorporation of an antibacterial substance, such as silver sulfadiazine (SAg), into polycaprolactone (PCL) tubes for nerve regeneration can improve the control of infections during the healing process. This paper reports a study on the structure and properties of extruded PCL/SAg tubes produced using different processing temperatures and screw speeds. The crystallinity values for the PCL/SAg tubes were lower than that for the pure PCL tube, probably due to interaction of the drug with the polymer chains. The flexural modulus of PCL/SAg tubes increased when lower values were used for the screw speed due to a hardening effect caused by the nature of the drug dispersion at a lower shear rate. The PCL/SAg tubes produced using lower screw speeds showed higher fatigue resistance and lower glass transition temperature, suggesting a greater dispersion of silver sulfadiazine in the PCL matrix. The PCL/SAg produced using 17 rpm and 120 °C as the screw speed and processing temperature, respectively, presented appropriate SAg dispersion, flexibility, toughness and fatigue resistance for application as a guide for nerve regeneration in joints and moving parts.