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Abstract The ability to print soft materials into predefined architectures with programmable nanostructures and mechanical properties is a necessary requirement for creating synthetic biomaterials that mimic living tissues. However, the low viscosity of common materials and lack of required mechanical properties in the final product present an obstacle to the use of traditional additive manufacturing approaches. Here, a new liquid‐in‐liquid 3D printing approach is used to successfully fabricate constructs with internal nanostructures using in situ self‐assembly during the extrusion of an aqueous solution containing surfactant and photocurable polymer into a stabilizing polar oil bath. Subsequent photopolymerization preserves the nanostructures created due to surfactant self‐assembly at the immiscible liquid–liquid interface, which is confirmed by small‐angle X‐ray scattering. Mechanical properties of the photopolymerized prints are shown to be tunable based on constituent components of the aqueous solution. The reported 3D printing approach expands the range of low‐viscosity materials that can be used in 3D printing, and enables robust constructs production with internal nanostructures and spatially defined features. The reported approach has broad applications in regenerative medicine by providing a platform to print self‐assembling biomaterials into complex tissue mimics where internal supramolecular structures and their functionality control biological processes, similar to natural extracellular matrices.
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Processing Parameter‐Performance Nexus in 3D Printing of Nanostructured Chiral Photonics
Abstract Precisely crafted hierarchical architectures found in naturally derived biomaterials underpin the exceptional performance and functionality showcased by the host organism. In particular, layered helical assemblies composed of cellulose, chitin, or collagen serve as the foundation for some of the most mechanically robust and visually striking natural materials. By utilizing structured materials in additive manufacturing techniques such as extrusion‐based 3D printing, the intrinsic deformation process can be used to implement bottom‐up design of printed constructs, offering the potential to create intricate macroscale geometries with embedded nanoscale functionality. In this study, comprehensive rheological and rheo‐optical characterization of structurally colored, photocurable liquid crystalline inks based on hydroxypropyl cellulose (HPC) are carried out to define the structural dynamics of the system under flow and following flow cessation. It is shown that the processing parameters selected for 3D printing can induce order or disarray in the extruded ink's liquid crystal nanostructure. Low to intermediate shear rates order the chiral nematic domains to yield intense structural color. In contrast, high shear rates induce elastic instabilities that diminish the filament's photonic quality. After establishing the processing parameter‐nanostructure relationship, the curing kinetics of these photocurable inks are tailored to facilitate the arrest of the liquid crystalline structure.
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- Award ID(s):
- 2146428
- PAR ID:
- 10612238
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Small
- Volume:
- 21
- Issue:
- 8
- ISSN:
- 1613-6810
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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