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Embedded ink writing (EIW) and direct ink writing (DIW) constitute the primary strategies for three-dimensional (3D) printing within the realm of material extrusion. These methods enable the rapid fabrication of complex 3D structures, utilizing either yield-stress support baths or self-supporting inks. Both these strategies have been extensively studied across a range of fields, including biomedical, soft robotics, and smart sensors, due to their outstanding print fidelity and compatibility with diverse ink materials. Particle additives capable of forming volume-filling 3D networks are frequently incorporated into polymer solvents. This integration is crucial for engineering the requisite microstructures essential for the formulation of successful support bath and ink materials. The interplay between the particle additives and polymer solvents is critical for achieving rheological tunability in various 3D printing strategies, yet this area has not been systematically reviewed. Therefore, in this critical review, we examined various mechanisms of particle–polymer interactions, the resulting microstructures, and their subsequent impact on mechanical and rheological properties. Overall, this work aims to serve as a foundational guideline for the design of next-generation materials in the field of extrusion additive manufacturing, specifically for EIW and DIW.
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NUCLEOS: TOWARD RAPID-PROTOTYPING OF ROBOTIC MATERIALS THAT CAN SENSE, THINK AND ACT
Robotic Materials are materials that have sensing, computation and, possibly actuation, distributed throughout the bulk of the material. In such a material, we envision semiconducting polymer based sensing, actuation, and information processing for on-board decision making to be designed, in tandem, with the smart product that will be implemented with the smart material. Prior work in printing polymer semiconductors for sensing and cognition have focused on highly energetic inkjet printing. Alternatively, we are developing liquid polymer extrusion processes to work hand-in-hand with existing solid polymer extrusion processes (such as Fused Deposition Manufacturing - FDM) to simultaneously deposit sensing, computation, actuation and structure. We demonstrate the successful extrusion printing of conductors and capacitors to impedance-match a new, higher-performance organic transistor design that solves the cascading problem of the device previously reported and is more amenable to liquid extrusion printing. Consequently, these printed devices are integrated into a sheet material that is folded into a 3-D, six-legged walking machine with attached electric motor.
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- PAR ID:
- 10081575
- Date Published:
- Journal Name:
- Proceedings of the ASME Conference on Smart Materials, Adaptive Structures, and Intelligent Systems
- ISSN:
- 2153-2001
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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