Influence of 3D printing parameters on the properties of PLA/clay nanocomposites

The aim of this work was to study the influence of printing temperature in the 3D printing process of PLA/clay nanocomposites. For this reason, PLA 4032D was melt compounded in a twin screw extruder with a layered silicate (Cloisite 30B) at 4 wt%. Then, using a single screw extruder, PLA and PLA/clay filaments were produced so as to obtain the required diameter (1.75 mm). Finally, dog-bone specimens were 3D printed via FDM technique using three different temperatures (185, 200 and 215°C) and such specimens were mechanically tested in tensile mode. Dynamic mechanical analysis (DMA) on PLA/clay filaments reported an increase of storage modulus both at 35°C and 70°C (8 and 40 %, respectively) in comparison to the PLA filament. Differential scanning calorimetry (DSC) demonstrated the ability of nanoclay to act as nucleating agent because cold crystallization temperature decreased of about 10°C. Finally, nanocomposite 3D printed samples exhibited always higher elastic modulus than PLA specimens and it increases at increasing printing temperature.