Effect of butyric anhydride modification on properties of wood-polylactic acid 3D-printed composites

Scotch pine wood flour was modified with butyric anhydride to determine the effect of wood modification on the properties of 3D-printed composites. The 3D printer filaments were obtained by mixing wood flour and polylactic acid (PLA) with a twin-screw extruder. The composites were printed via a 3D printer from the obtained filaments. The mechanical, thermal, and morphological properties of the composites were investigated. According to the mechanical test results, the tensile strength values of the modified wood flour (MWF)-added composites were higher than the unmodified wood flour (UMWF)-added composites. It was also observed that the flexural strength and flexural modulus of MWF-added composites decreased compared to the UMWF-added composites. According to the investigation of the thermal properties of the composites, the thermal degradation temperature value of the 20% MWF-added PLA composite was higher than other composites. Therefore, through the investigation of breaking surfaces of the composites using scanning electron microscopy, it was observed that the interface bonding between PLA polymer matrix and wood flour was improved by modification.