Liquid metal fibers are increasingly used in soft multifunctional materials and soft electronics due to their superb stretchability, high conductivity, and lightweight. This work presents a systematic study of the electrospinning process of liquid metal microfibers. Compared to other methods that usually produce fibers thicker than 100 μm, electrospinning is a facile and low‐cost method of producing liquid metal fibers in the range of 10–100 μm. Specifically, core‐sheath liquid metal microfibers are fabricated with a highly conductive liquid metal core and a super‐stretchable thermoplastic elastomer sheath. This manufacturing process uses a liquid metal emulsion as the core solution, which circumvents manufacturing failures caused by the high surface tension of liquid metals. The influence of key processing parameters such as core flow rate, sheath flow rate, and applied voltage on the fiber diameter and morphology is studied by experiments. The mechanical and electrical properties of the as‐fabricated liquid metal microfibers, mats, and yarns are tested and discussed.
Two‐photon polymerization (TPP) is widely used to create 3D micro‐ and nanoscale scaffolds for biological and mechanobiological studies, which often require the mechanical characterization of the TPP fabricated structures. To satisfy physiological requirements, most of the mechanical characterizations need to be conducted in liquid. However, previous characterizations of TPP fabricated structures are all conducted in air due to the limitation of conventional micro‐ and nanoscale mechanical testing methods. In this study, a new experimental method is reported for testing the mechanical properties of TPP‐printed microfibers in liquid. The experiments show that the mechanical behaviors of the microfibers tested in liquid are significantly different from those tested in air. By controlling the TPP writing parameters, the mechanical properties of the microfibers can be tailored over a wide range to meet a variety of mechanobiology applications. In addition, it is found that, in water, the plasticly deformed microfibers can return to their predeformed shape after tensile strain is released. The shape recovery time is dependent on the size of microfibers. The experimental method represents a significant advancement in mechanical testing of TPP fabricated structures and may help release the full potential of TPP fabricated 3D tissue scaffolds for mechanobiological studies.
more » « less- PAR ID:
- 10391751
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Functional Materials
- Volume:
- 33
- Issue:
- 3
- ISSN:
- 1616-301X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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