Renewable Nanocomposites for Additive Manufacturing Using Fused Filament Fabrication

Additive manufacturing provides an opportunity to redefine sustainability for plastic products, as polyolefins, which dominate traditional plastics manufacturing, are generally unsuitable for 3D printing. One of the most widely used 3D printing technologies is fused filament fabrication (FFF), where a thermoplastic filament is melted and extruded to build the object layer-by-layer. The printing performance can be quantified in terms of mechanical properties and dimensional accuracy of the part. Here we demonstrate the ability to print high-quality parts via FFF using a biorenewable polyamide-11 (PA-11). The PA-11 monomer, 11-aminoundecanoic acid, is derived directly from castor beans by hydrolysis, methylation, and heat treatment of its oils. The elastic modulus and dimensional accuracy can be further improved by the incorporation of a natural nanofiller, sepiolite. The role of print orientation and filler content are systematically investigated, with elastic moduli greater than 1.1 GPa obtained for the o...