3D Printing of Natural Rubber

Fused Filament Fabrication (FFF) dominates Additive Manufacturing (AM) due its cost and adaptability but is limited to the materials which can be formed into cylindrical filaments. Fused Form developed Colombia’s first large format pellet 3D printer which has the ability to eliminate the need for producing filaments and feeding raw materials into the feed system. The FF Pellet 600+ (Figure 1) has the ability to be customized in regard to the screw types and nozzle geometries. This customizability will allow for the Polymer Engineering Center (PEC) to investigate adaptability of Natural Rubber (NR) in AM.

Figure 1. FusedForm’s FF Pellet 600+ 3D printer

Natural Rubber’s highly viscoelastic nature allows the design of high-performance products that can withstand large reversible deformations at large stress states. In terms of processability, that is where raw NR underperforms as its ultra-high molecular weight and viscosity leads to extrusion defects which will lead to dimensional instability during printing. The PEC aims to use the NR characterization study to understand the printability of NR and its limitations by using the FF Pellet 600+ and a custom-made screw profile and feed system for elastomer blends.

The following research topics are being addressed:

  • Elastomer Extrusion Screw Design
  • Extrusion Defects of Highly Viscoelastic Blends
  • Warpage Study of Vulcanized AM Parts
  • AM Parts vs. Compression Molded Parts