Electrical conductivity of graphene/Si3N4 doped PLA produced by fused filament fabrication

Today, the technological, scientific and industrial use of micro- or nano-scale products has rapidly expanded. Nanoparticles are added to metal, ceramic and polymer materials to produce nanocomposite materials. Polymer matrix nanocomposites have advantages over other materials in terms of weight, performance and price. As known from the literature, imparting electrical conductivity to thermoplastic materials such as polylactic acid (PLA) is possible. The industrial use of thermoplastic matrix has been the focus of nanocomposites due to its low cost, ease of production and recycling. Research on the use of 3D printers in the production of nanoscale-doped thermoplastics has been less common. 3D printing is an additive manufacturing method compared to traditional processing methods. Additive manufacturing is based on adding layer by layer to reduce production costs and reduce the production cycle. This study prepared nanocomposite material by adding nano-sized graphene and Si3N4 to PLA material at 0.5, 1, 2 and 3 wt. %. The prepared polymer matrix nanocomposite groups were produced using a fused filament fabrication (FFF-3D) printer and their electrical conductivity was examined at the five different points by the four-point probe method. According to the test results, the electrical conductivities of 1 and 2 % doped PLA are very close. But the 1 % doped samples is the composite group with the best conductivity with a value of 153.44 S/m. A value of 151.25 S/m followed this for 2 % doped PLA and 138.57 S/m for 3 % doped PLA. Thus, it was concluded that the electrical conductivity was reduced with the increased dope rate. Also, all samples' hardness was measured by the Shore D test. Although the increase in the hardness value of the samples did not affect as much as the increase in the dope ratio, the hardness values increased with the increase in the nanoadditive ratio.