Thermal characterization and local electrical mapping of 3D printed self-responsive polymers

3D printing is an additive manufacturing process, that allows producing objects with complicated shapes simply by adding the building material layer by layer without any material waste. Among several 3D printing technologies, the Fused Deposition Modelling (FDM) is the most suitable one in the field of thermoplastic materials. With respect to the current literature, the present study aims to extend this technology to self-responsive materials, able to sense external stimuli appropriately. In particular, promising 3D printed self-heating objects have been made of nanocomposite material (Acrylonitrile-Butadiene-Styrene ABS filled with Carbon Nano-Tubes CNT) via FDM. In this case, the external stimulus is the electrical current flowing inside the printed item, while its response consists of an increase in temperature by Joule effect. Moreover, the electrical properties have been tailored by properly determining the direction of printed filaments allowing the management of the generated heat in different zones of the printed object. In this work, thermal analysis has been fundamental to choose the extrusion temperature during the printing phase, while Atomic Force Microscopy (AFM) and Scanning electron Microscopy (SEM) have provided a mapping of conductive filler distribution correlated to the electrical properties of the whole sample