3D printed polylactic acid - hemp fiber composites: Mechanical, thermal, and microcomputed tomography data

Area of Science:

• Materials Science
• Additive Manufacturing
• Polymer Composites

Background:

• Polylactic acid (PLA) is a biodegradable thermoplastic with growing applications.
• Hemp fiber offers a sustainable and potentially cost-effective reinforcement for polymers.
• Additive manufacturing (AM) techniques like fused filament fabrication (FFF) enable complex part geometries.

Purpose of the Study:

• To investigate the effect of hemp fiber surface treatments on PLA composites for FFF.
• To characterize the thermal and mechanical properties of these novel composite materials.
• To assess the viability of minimally processed hemp fiber as a filler in AM.

Main Methods:

• Hemp fiber was untreated or treated with sodium hydroxide or APTES.
• Composites with 10 wt.% hemp fiber were prepared via solvent processing.
• Filaments were extruded and tensile test specimens were fabricated using FFF.
• Thermal properties were analyzed, and mechanical testing was performed.

Main Results:

• Surface treatments influenced the thermal properties of PLA/hemp fiber composites.
• Microcomputed tomography revealed composite microstructure.
• Tensile mechanical properties varied significantly with hemp fiber surface treatment.
• FFF-printed specimens demonstrated the potential of these composites.

Conclusions:

• Minimally processed hemp fiber can be effectively incorporated into PLA for additive manufacturing.
• Surface modification of hemp fiber is crucial for optimizing composite performance.
• These findings support the use of natural fibers as mechanical enhancers in thermoplastic composites for AM.