Tooling engineering and its role in manipulating fiber spinning and enabled nanostructures

One of the challenges to multimaterial multifunctional composite fibers is their scalability during the fabrication process. Additive manufacturing is a cost-effective tooling solution for fast prototyping fiber spinning spinnerets. This work demonstrates a laser powder bed fusion-based tri-axial spinneret that could accommodate three different materials as inner, middle, and outer layers. In the first work, continuous graphene nanoplatelets (GnPs) channel was embedded between core polymer and sheath polymer layers to simultaneously achieve electrical conductivity and high mechanical properties. This multimateiral, multichannel system is too expensive with conventional manufacturing. Our 3D printed spinneret will generate shear stress during the polymer drawing process, resulting in thinning and alignment of the two-dimensional (2D) GnPs. Similarly, in the second research, a multilayered chemiresistor for volatile organic compounds (VOCs) was fabricated in a single step. Each layer played a significant role in the overall sensor functionalities. For instance, (i) the hollow core supported inline gas transportation, (ii) the porous polymer inner layer assisted VOC diffusion, (iii) the middle electrical conductive layer responded to VOCs types and concentrations, and (iv) the outer mechanically stable layer secured sensor's physical stability.