Designer patterned functional fibers via direct imprinting in thermal drawing

Abstract

Creating micro/nanostructures on fibers is beneficial for extending the application range of fiber-based devices. To achieve this using thermal fiber drawing is particularly important for the mass production of longitudinally uniform fibers up to tens of kilometers. However, the current thermal fiber drawing technique can only fabricate one-directional micro/nano-grooves longitudinally due to structure elongation and polymer reflow. Here, we develop a direct imprinting thermal drawing (DITD) technique to achieve arbitrarily designed surface patterns on entire fiber surfaces with high resolution in all directions. Such a thermal imprinting process is simulated and confirmed experimentally. Key process parameters are further examined, showing a process feature size as small as tens of nanometers. Furthermore, nanopatterns are fabricated on fibers as plasmonic metasurfaces, and double-sided patterned fibers are produced to construct self-powered wearable touch sensing fabric, revealing the bright future of the DITD technology in multifunctional fiber-based devices, wearable electronics, and smart textiles.

3D Printing in Fiber-Device Technology

“…Long-term microscale implantable devices with nanoscale metallic glass probes and microfluidic features allow localized pharmacological neural stimulation and monitoring [98]. Triboelectric nanogenerators fiber devices for mechanical force detection with surface patterns were designed as a wearable multipoint touch sensor [99]. The triboelectric effect was also used in fiber technology to sense finger bending conditions and breathing monitoring [6].…”

Advanced Thermally Drawn Multimaterial Fibers: Structure-Enabled Functionalities

“…Beyond the inner structure, creating surface structure could also endow thermally drawn fibers with many other unique functionali-ties, e.g., hydrophobic surface, antimicrobial effect, nerve guidance scaffolds, and coloration [78][79][80]. Therefore, several attempts have been reported to create surface patterns on thermally drawn fibers by far [81][82][83][84][85][86].…”

“…To create high-resolution surface patterns in arbitrary directions, the direct imprinting in thermal drawing (DITD) technique is proposed to combine the thermal drawing technique and nanoimprinting [81]. As shown in the schematic in Figure 6(e), a pair of rollers with surface patterns is placed right below the furnace.…”

Microstructured multimaterial fibers for efficient optical detection

“…During the thermal drawing process, the preform was heated to a fluid state, and then drawn into uniform and long continuous fibers under external traction. [13][14][15][16][17] Further processing these fibers with the help of the external field (e.g., laser and heat-treatment) enables to generate another type of microstructured multimaterial fibers. Specifically, the interfaces between the disparate fiber components obtained via thermal drawing are thermodynamic instability due to their different surface tension.…”

“…The first one is usually directly drawn from a macroscopic preform and it is characterized by the multimaterial fibers containing continuous optoelectronic components. During the thermal drawing process, the preform was heated to a fluid state, and then drawn into uniform and long continuous fibers under external traction 13‐17 . Further processing these fibers with the help of the external field (e.g., laser and heat‐treatment) enables to generate another type of microstructured multimaterial fibers.…”