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Conducting polymer hydrogels combine electrical conductivity and tunable water content, rendering them strong candidates for a range of applications including biosensors, cell culture platforms, and energy storage devices. However, these hydrogels are mechanically brittle and prone to damage, prohibiting their use in emerging applications involving dynamic movement and large mechanical deformation. Here, we demonstrate that applying the concept of architecture to conducting polymer hydrogels can circumvent these impediments. A stereolithography 3D printing method is developed to successfully fabricate such hydrogels in complex lattice structures. The resulting hydrogels exhibit elastic compressibility, high fracture strain, enhanced cycling stability, and damage-tolerant properties despite their chemical composition being identical to their brittle, solid counterparts. Furthermore, concentrating the deformation to the 3D geometry, rather than polymer microstructure, effectively decouples the mechanical and electrical properties of the hydrogel lattices from their intrinsic properties associated with their chemical composition. The confluence of these new physical properties for conducting polymer hydrogels opens broad opportunities for a myriad of dynamic applications.
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This content will become publicly available on August 27, 2026
Effects of Polymer Matrix Structures on Metallic Growth in Electrically assisted Vat Photopolymerization for Heterogeneous Metal-Polymer Printing
Abstract Although metal-polymer heterogeneous structures possess exceptional mechanical, thermal, and electrical properties, their fabrication remains challenging due to the reactive nature of the materials and the risk of property alteration during manufacturing. This study investigates the printing quality of metal-polymer structures fabricated using electrically assisted heterogeneous material printing (EF-HMP), focusing on the relationship between the polymer and metal layers and their electrical properties. The developed printing solution enables the transport of metal ions for metal printing onto a polymer matrix under a controlled electrical field. The study emphasizes the critical role of polymer microstructures in influencing metal electrodeposition, including printing time and morphology. Three microstructure geometries—rectangular, trapezoidal, and semicircular—were designed based on manufacturability and surface-area-to-volume ratio and evaluated for their impact on metal-polymer fabrication via EF-HMP process. Scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), and electrical conductivity tests revealed that the semicircular microstructure provided the best printing performance, forming a robust metal structure in a short time and achieving the lowest resistance of 12 kΩ. This research highlights the potential of EF-HMP for metal-polymer fabrication, offering new insights into the influence of interfacial polymer microstructures on metal printing at room temperature. These findings pave the way for optimizing the design and functionality of metal-polymer components in metamaterials, thermal management, and flexible electronics applications.
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- PAR ID:
- 10634366
- Publisher / Repository:
- ASME
- Date Published:
- Journal Name:
- Journal of Micro and Nano-Manufacturing
- ISSN:
- 2166-0468
- Page Range / eLocation ID:
- 1 to 33
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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