3D Printing of Aramid Nanofiber Composites by Stereolithography

Vat photopolymerization is a versatile 3D-printing method that produces parts using polymeric materials with uniform mechanical properties, high-quality surface finish, and high-resolution features. However, it is challenging to make composite materials with vat photopolymerization mainly because of the imperfect filler dispersion in the photoresin. Herein, we describe a methodology to incorporate aramid nanofibers (ANFs) into a 3D-printable photoresin as a dispersion, followed by a solvent-exchange process that limits anisotropic shrinkage and cracking of the printed polymer. By incorporating 0.60 wt % ANFs, both the tensile strength and toughness increased by 264% and 219%, respectively, while Young's modulus had a 406% increase compared to the control photoresin.