Reactive Processing of 3D Printed ABS Structures Formed by Fused Deposition Modeling to Reduce Structural Anisotropy

Fused deposition modeling (FDM) is one of the most common additive manufacturing methods, which allows the fabrication of complex structures and customization. However, due to its layer-by-layer nature, the resultant structures exhibit anisotropic properties. A primary reason for the anisotropy is weak interactions and poor entanglement between subsequently deposited layers. Methods to increase inter-layer adhesion include post-deposition heating, which results in loss of fidelity of the fabricated shape to the target structure. To address this shortcoming, our group has modified an FDM printer to allow for the reactive processing of the interlayer interface as a part of the deposition. This is realized by adding a UV-LED optical fiber to an FDM 3D printer, which is designed to initiate a reaction at the inter-layer interface. This presentation will present results that examine the success of this novel processing scheme. Samples of ABS that include a photo-initiator and a crosslinker to form covalent bonds across the interlayer interface are printed with this modified printer, and its tensile properties and anisotropy monitored. This presentation will report the impact of the loading of photo-initiator and crosslinker on the mechanical properties of the printed sample.