Bioactive and bactericidal biocomposites based on <scp>PBAT</scp>/<scp>PLA</scp> with hydroxyapatite and tannin derivative

Abstract The aim of this study was to develop innovative bioactive and bactericidal composites by enhancing the biodegradable Ecovio® blend, composed of poly(butylene adipate‐co‐terephthalate) (PBAT) and poly(lactic acid) (PLA), with hydroxyapatite (HA) and an amino‐functionalized tannin derivative (TN) envisioning biomedical applications. Initially, TN purification was optimized to maximize yield without compromising quality. Biocomposites were then prepared via melt‐compounding using fixed proportions of each biofiller, ensuring a direct evaluation of the individual and combined effects of HA and purified tannin (pTN). The findings indicate that the incorporation of biofillers did not compromise the integrity of the polymer matrix while influencing its morphology and chemical composition. Rheological analysis suggests that pTN acted as a lubricant, reducing viscosity, whereas HA increased viscosity due to microparticle confinement. Mechanical tests indicated a compressive modulus between 30 and 50 MPa, suitable for hard tissue engineering. Furthermore, bioactivity assays confirmed that samples containing HA and pTN exhibited bioactive behavior, while antimicrobial tests demonstrated that samples with pTN possessed bactericidal properties. These results suggest that the strategic incorporation of HA and pTN into the PBAT/PLA blend is a promising approach for developing multifunctional biomaterials. Highlights Biocomposites PBAT/PLA/HA/TN were developed for biomedical applications. Biofillers (HA and TN) modified viscosity without degrading the polymer matrix. Compressive modulus (30–50 MPa) aligns with hard tissue engineering needs. HA conferred bioactivity, while TN provided bactericidal properties. PBAT/PLA biocomposites with HA and TN show potential for medical use.