Abstract Fused Filament Fabrication, better known as Fused Deposition Modeling®, is currently the most widespread 3D Printing Technology. There has been a significant demand for developing flame-retardant filaments. Thereby enabling them, for example, in electronics and automotive applications. In this study, commercial PLA filament was modified by the addition of 1, 3 and 5% (%wt.) of expandable graphite. The composites were reprocessed, via extrusion, into filaments for Fused Filament Fabrication. Thermal properties of the filament composites were evaluated by thermogravimetric analysis and differential scanning calorimetry. Mechanical properties of thermo-pressed specimens indicated that no strong adhesion was promoted between the filler and matrix. This is a challenge with expandable graphite reported by many authors. All composites with expandable graphite achieved the V-2 rating of UL-94 flammability test. In spite of this, the results indicated that flammability of the PLA was reduced. All composite filaments were printable and prototypes were successfully 3D printed.

In the present study, PHB film was prepared by thermo-compression molding and PHB nanofibers mat was produced through electrospinning process. The nanofibers morphology was confirmed by SEM. The film and nanofibers crystallinity degree was estimated by different methods. FTIR and WAXD indicated that PHB film is more crystalline than PHB nanofibers. However, DSC analysis suggested that a PHB nanofibers phase change might occur while the temperature rises. SAXS indicated that PHB film and nanofibers have low electron density contrast between the alternating crystalline and amorphous layers. The influence of nanofiber morphology on the mechanical, surface and thermal properties was also shown in TG analysis, tensile tests and contact angle measurements.