Feasibility and Characterization of Common and Exotic Filaments for Use in 3D Printed Terahertz Devices

Abstract

Recent years have seen an influx of applications utilizing 3D printed devices in the terahertz regime. The simplest, and perhaps most versatile, modality allowing this is Fused Deposition Modelling. In this work, a holistic analysis of the terahertz optical, mechanical and printing properties of 17 common and exotic 3D printer filaments used in Fused Deposition Modelling is performed. High impact polystyrene is found to be the best filament, with a useable frequency range of 0.1-1.3 THz, while remaining easily printed. Nylon, polylactic acid and polyvinyl alcohol give the least desirable terahertz response, satisfactory only below 0.5 THz. Interestingly, most modified filaments aimed at increasing mechanical properties and ease of printing do so without compromising the useable terahertz optical window. Abstract Recent years have seen an influx of applications utilizing 3D printed devices in the terahertz regime. The simplest, and perhaps most versatile, modality allowing this is Fused Deposition Modelling. In this work, a holistic analysis of the terahertz optical, mechanical and printing properties of 17 common and exotic 3D printer filaments used in Fused Deposition Modelling is performed. High impact polystyrene is found to be the best filament, with a useable frequency range of 0.1-1.3 THz, while remaining easily printed. Nylon, polylactic acid and polyvinyl alcohol give the least desirable terahertz response, satisfactory only below 0.5 THz. Interestingly, most modified filaments aimed at increasing mechanical properties and ease of printing do so without compromising the useable terahertz optical window.

Material extrusion‐based additive manufacturing of polypropylene: A review on how to improve dimensional inaccuracy and warpage

“…Although PP has been reported as difficult to use thermoplastic for ME‐AM due to the aforementioned warpage issues, 3D‐printed PP has been widely used in specific applications such as in applied chemistry. For instance, Gordeev et al .…”

“…Other studies that revealed PP's potential as an engineering material with excellent stability against chemicals include the production of chemical process laboratories or chemical reaction vessels, for example, for the synthesis of bicyclic and tetracyclic heterocycles, the anti‐inflammatory drug ibuprofen, or multistep organic syntheses, the production of microfluidic devices for the medical and chemical industry, the fabrication of tailored reactor devices for mass spectrometry, or reactionware devices for continuous‐flow organic reactions . Additionally, various researchers recommended the use of 3D‐printed PP for various promising applications, such as for a chemically resistant laboratory equipment for the processing of semiconductors, for terahertz devices, or for a cheap and light weight alternative for the electrolysis of water …”

Design and fabrication of 3-D printed conductive polymer structures for THz polarization control

“…1(d), respectively. The absorption coefficient of this material is higher than any other printable plastic tested until now [7]. The highly dispersive behavior of the refractive index is caused by the presence of carbon black in the PLA host.…”

“…Print settings were chosen to give a nozzle temperature of 220ºC, bed temperature of 50ºC and print speed of 80 mm/s. To retrieve the optical properties of CPLA, a 0.22 mm thick solid disk was printed and tested using THz transmission spectroscopy in a set up similar to the one used by Squires et al [7]. The refractive index and absorption coefficient of CPLA are shown in Fig.…”

“…Unfortunately, the materials used for optical components, for example glass, are opaque at terahertz frequencies. To address this problem, researchers have turned their attention to 3D printed technology given the low attenuation of some printable plastics in this frequency range [7]. Additionally, the resolution of conventional 3D printers is high enough to fabricate components for the THz range (0.4 mm aprox.).…”