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Design of soft matter for additive processing

Nature Synthesis volume 1, pages 592–600 (2022)Cite this article

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Abstract

Digital assembly via extrusion-based additive manufacturing, or three-dimensional (3D) printing, grants the opportunity to attain exquisite control over material structure and composition at the local (‘voxel’) level. The synthetic incorporation of a diverse array of chemistries into 3D-printed soft materials has expanded its use into many application areas. However, substantial opportunity exists for synthesizing materials in which the functional microstructure (at both filler and molecular levels) interacts with the processing flows of extrusion-based manufacturing to achieve unique and enhanced properties. Here we articulate principles for designing and synthesizing soft materials with the potential to generate printed structures with superlative mechanical and stimuli-responsive properties. Specifically, we consider the rheological requirements of printing via direct ink writing and materials extrusion, and examine materials that show printing-directed alignment or trapping of tailored non-equilibrium structures. Finally, we discuss characterization approaches that connect filament-level microstructure with macroscopic behaviour, thus ‘closing the loop’ of material development. Collectively, these create the potential for additive manufacturing to achieve voxel-level control of composition, microstructure and properties.

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Fig. 1: The design process to digital assembly by using extrusion-based additive processing.
Fig. 2: Designing yield stress interactions within the printing process.
Fig. 3: Imparting functionality during the printing process.
Fig. 4: Controlling the functionality of 3D-printed material via external fields.
Fig. 5: Characterization methods used in 3D printing for structural analysis at different length scales, from the molecular to the macroscopic scale.

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Acknowledgements

We thank J. A. Lewis for helpful discussions. This work was partially supported by the MRSEC programme of the National Science Foundation (DMR-2011750) through the Princeton Center for Complex Materials. J.M.T. acknowledges support from an ARO MURI award (no. W911NF-17-1-0351).

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Authors and Affiliations

  1. Department of Chemical and Biological Engineering, Princeton University, Princeton, NJ, USA

    Chun Lam Clement Chan & Emily Catherine Davidson

  2. Department of Materials Science and Engineering, University of Illinois Urbana-Champaign, Urbana, IL, USA

    Jay Matthew Taylor

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This perspective was conceived by E.C.D., and written by C.L.C.C., E.C.D. and J.M.T.

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Correspondence to Emily Catherine Davidson.

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Chan, C.L.C., Taylor, J.M. & Davidson, E.C. Design of soft matter for additive processing. Nat. Synth 1, 592–600 (2022). https://doi.org/10.1038/s44160-022-00115-3

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