Investigation on the thermal stability and morphology of PLA/PCL/Starch ternary blends containing hydroxyapatite nanoparticles and triclosan Shakiba Yavarpanah1, Javad Seyfi1, Hossein Ali Khonakdar2* 1 Department of Chemical Engineering, Shahrood Branch, Islamic Azad University, Shahrood, Iran 2 Leibniz-Institut für Polymerforschung Dresden e.V., Hohe Strasse 6, D-01069 Dresden, Germany Abstract Nowadays, developing innovative solutions for environmental problems have turned into the major concerns of researchers around the world. Therefore, replacement of petroleum-based plastics with biodegradable polymers is one of the promising solutions. In this study, an entirely biodegradable multicomponent system based on poly(lactic acid) (PLA), starch and poly(caprolactone) (PCL) was prepared via the melt-mixing technique. To achieve a better compatibility among the components, hydroxyapatite nanoparticles (nHA) and triclosan were added to the above-mentioned ternary blend. PLA was the matrix to which starch was added as a filler making the final material more hydrophilic. On the other hand, PCL was added to enhance the blend toughness. Triclosan and nHA were also added to impart some properties such as antibacterial behavior and mechanical strength, respectively. It was found that the combination of nHA and triclosan resulted in a great level of compatibilization. Several samples containing 1, 3 and 5 wt.% of nHA were prepared, and then, characterized by scanning electron microscopy (SEM), and thermogravimetric analysis (TGA). The morphology results showed that addition of nHA enhanced the compatibility among PLA, PCL and starch phases. TGA results also showed that in different temperature zones, the samples exhibited a different thermal stability due to the complexity of the system. All in all, the sample containing 1 wt.% of nanoparticles was found to exhibit an optimum behavior. Keywords: Poly(lactic acid); Poly(caprolactone); Starch; Morphology; Nanocomposite