Effect of magnetic zinc-magnesium ferrite nanoparticles on the thermal, physical and mechanical properties of poly(lactic acid)

Functional PLA/ferrite composites are promising materials for biomedical applications due to their magnetic and electrical properties. The present study focuses on the influence of incorporating magnetic Zn 0.5 Mg 0.5 Fe 2 O 4 nanoparticles (M) on the thermal, physicochemical, and mechanical properties of PLA (P) composites. The P/M composites were processed by the melt blending extrusion method with Zn 0.5 Mg 0.5 Fe 2 O 4 nanoparticle concentrations of 0, 0.25, 0.5, 0.75, and 1.0 wt%. The X-ray diffraction analysis confirmed the presence of the characteristic peaks corresponding to the crystallographic planes of the magnetic nanoparticles (MNPs) in the P/M composites. Scanning electron microscopy (SEM) analysis indicates the dispersion of small aggregates of MNPs within the polymeric material. Differential scanning calorimetry (DSC) analysis was used to determine the thermal stability of the composites. The results demonstrated changes in the glass transition temperature (T g ) and cold crystallization temperature (T cc ) with increasing MNPs content in the material. The mechanical properties show that adding nanoparticles slightly decreases tensile strength (from 66.9 to 61.9 MPa) and Young's modulus (from 3155.5 to 3090.8 MPa). However, the elongation at break (from 4.3 to 6.9 %) and the melt flow index (from 96.1 to 158.8 g/min) increased, suggesting that nanoparticles may act as plasticizers into the polymer matrix. The saturation magnetization ( Ms ) of the composites increased with the nanoparticles content, achieving values between 0.08 and 0.38 emu/g. The composites also demonstrated an adsorption capacity for urea (14.75 %) and of creatinine (4.8 %). These results indicate that these magnetic composites can be novel candidates as functional materials for biomedical and technological applications.