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Abstract Thermoplastic elastomers (TPEs) are nanostructured, melt‐processable, elastomeric block copolymers. When TPEs that form cylindrical or lamellar nanostructures are macroscopically oriented, their material properties can exhibit several orders of magnitude of anisotropy. Here it is demonstrated that the flows applied during the 3D printing of a cylinder‐forming TPE enable hierarchical control over material nanostructure and function. It is demonstrated that 3D printing allows for control over the extent of nanostructural and mechanical anisotropy and that thermal annealing of 3D printed structures leads to highly anisotropic properties (up to 85 × anisotropic tensile modulus). This approach is leveraged to print functional soft 3D architectures with tunable local and macroscopic mechanical responses. Further, these printed TPEs intrinsically achieve melt‐reprocessability over multiple cycles, reprogrammability, and robust self‐healing via a brief period of thermal annealing, enabling facile fabrication of highly tunable, robust, and recyclable soft architectures.
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Extrusion‐Based Printing of Nanostructured Fatty Acid Gels Incorporated in Hydrogels
ABSTRACT Soft materials with unique nanostructures such as lamellar, hexagonal, and cubic morphologies can replicate complex structures that have potential in various fields, including biomedical and industrial applications. However, a key challenge in advancing the broader applications of 3D printing for these nanostructured soft materials is insufficient mechanical properties that hinder their printability and compromise structural stability in the final product. In this study, the suitability of a fatty acid‐based lamellar gel is evaluated for direct extrusion‐based 3D printing. The lamellar gel with varying water content is integrated with a photocurable hydrogel to preserve the shape and stability of the final prints. Complex 2D and 3D design patterns are used to assess extrusion behavior, structural stability, and print precision under varying pressures. Small‐angle X‐ray Scattering (SAXS) measurements reveal the formation of lamellar nanostructures and confirm their retention after photocuring in various gels. Rheological analysis confirms that these gels exhibit key properties suitable for extrusion‐based 3D printing, such as shear‐thinning behavior. Additionally, tensile testing is conducted to evaluate the mechanical properties across cured print samples. This study underscores the potential of nanostructured gels as a robust and versatile platform, facilitating the development of materials engineered for various applications.
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- Award ID(s):
- 2301605
- PAR ID:
- 10593395
- Publisher / Repository:
- Wiley
- Date Published:
- Journal Name:
- Journal of Applied Polymer Science
- ISSN:
- 0021-8995
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript
- Journal Article:
- https://doi.org/10.1002/app.57328
