Beneficial usage of recycled polymer particulates for designing novel 3D printed composites

In this paper, we report the synthesis of novel 3D printed composites using particulates of Nylon and Polyester as functional additives. Nylon- and Polyester-based composites were designed by adding 5 wt% (Resin-5%Polyester or Resin-5%Nylon), 10 wt% (Resin-10%Polyester or Resin-10%Nylon), and 20 wt% (Resin-20%Polyester or Resin-20%Nylon) Polyester or Nylon particulates in the photopolymer resin matrix. The mechanical behavior study showed that the addition of both Polyester and Nylon particulates had a deleterious effect; for example, the baseline samples had a tensile strength of ~ 19 MPa, however, as the volume fraction of Polyester particulates was increased, the tensile strength decreased to ~ 12 MPa in Resin-5%Polyester, thereafter slightly increased to ~ 14 MPa in both Resin-10%Polyester and Resin-20%Polyester, respectively. The particulate additives had a beneficial effect on the tribological behavior. For example, as compared to 3D printed resin, the specific wear rate decreased by one order of magnitude from ~ 4.68 × 10⁻⁴ mm³/Nm in pure resin to ~ 3.42 × 10⁻⁵ mm³/Nm in Resin-20%Polyester (~ 13 .7 times reduction) and µ_mean decreased significantly from ~ 0.42 in pure resin to ~ 0.08 in Resin-20%Polyester (~ 5.2 times reduction), respectively.