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Abstract 4D printing technology enables the fabrication of constructs capable of shape transformation when exposed to external stimuli. Epoxy‐based shape memory polymers (SMPs) have shown great potential for various 4D printing applications. However, due to their thermocurable nature, the fabrication of 4D constructs using epoxy‐based materials is often limited to a mold casting strategy, limiting design flexibility and often yielding flat structures. In this work, photocurable smart 4D inks are developed by integrating polyethylene glycol diacrylate (PD) into epoxy‐based materials. These inks undergo a two‐step crosslinking process: i) photocuring of the PD network, and ii) thermocuring of the SMP, resulting in an interpenetrating polymer network (IPN). The inclusion of PD in the 4D inks not only enables the formation of complex shapes via the restructuring step but also allows for fine‐tuning of mechanical properties and thermal responsiveness. Additionally, these inks offered greater versatility in employable fabrication techniques, including mold casting, photolithography, and stereolithography (SLA).
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Stereolithographic 4D Bioprinting of Multiresponsive Architectures for Neural Engineering
Abstract 4D printing represents one of the most advanced fabrication techniques for prospective applications in tissue engineering, biomedical devices, and soft robotics, among others. In this study, a novel multiresponsive architecture is developed through stereolithography‐based 4D printing, where a universal concept of stress‐induced shape transformation is applied to achieve the 4D reprogramming. The light‐induced graded internal stress followed by a subsequent solvent‐induced relaxation, driving an autonomous and reversible change of the programmed configuration after printing, is employed and investigated in depth and details. Moreover, the fabricated construct possesses shape memory property, offering a characteristic of multiple shape change. Using this novel multiple responsive 4D technique, a proof‐of‐concept smart nerve guidance conduit is demonstrated on a graphene hybrid 4D construct providing outstanding multifunctional characteristics for nerve regeneration including physical guidance, chemical cues, dynamic self‐entubulation, and seamless integration. By employing this fabrication technique, creating multiresponsive smart architectures, as well as demonstrating application potential, this work paves the way for truly initiation of 4D printing in various high‐value research fields.
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- Award ID(s):
- 1642186
- PAR ID:
- 10063934
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Biosystems
- Volume:
- 2
- Issue:
- 9
- ISSN:
- 2366-7478
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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