Fluid Flow Templating of Polymeric Soft Matter with Diverse Morphologies

• Published in: Advanced materials (Weinheim) Vol. 35; no. 16; pp. e2211438 - n/a
• Main Authors: Bang, Rachel S., Roh, Sangchul, Williams, Austin H., Stoyanov, Simeon D., Velev, Orlin D.
• Format: Journal Article
• Language: English
• Published: Germany Wiley Subscription Services, Inc 01.04.2023
• Subjects: Biopolymers; Colloiding; Fluid flow; Materials science; Morphology; Nanofabrication; nanoscience and technology; polymer colloids; Polymers; processing; soft matter; processing; soft matter; polymer colloids; nanoscience and technology; nanofabrication
• ISSN: 0935-9648; 1521-4095
• DOI: 10.1002/adma.202211438

It is challenging to find a conventional nanofabrication technique that can consistently produce soft polymeric matter of high surface area and nanoscale morphology in a way that is scalable, versatile, and easily tunable. Here, the capabilities of a universal method for fabricating diverse nano‐ and micro‐scale morphologies based on polymer precipitation templated by the fluid streamlines in multiphasic flow are explored. It is shown that while the procedure is operationally simple, various combinations of its intertwined mechanisms can controllably and reproducibly lead to the formation of an extraordinary wide range of colloidal morphologies. By systematically investigating the process conditions, 12 distinct classes of polymer micro‐ and nano‐structures including particles, rods, ribbons, nanosheets, and soft dendritic colloids (dendricolloids) are identified. The outcomes are interpreted by delineating the physical processes into three stages: hydrodynamic shear, capillary and mechanical breakup, and polymer precipitation rate. The insights into the underlying fundamental mechanisms provide guidance toward developing a versatile and scalable nanofabrication platform. It is verified that the liquid shear‐based technique is versatile and works well with many chemically diverse polymers and biopolymers, showing potential as a universal tool for simple and scalable nanofabrication of many morphologically distinct soft matter classes. Versatile nanofabrication processes, where liquid flow templates polymer solvent–nonsolvent precipitation, can produce at least 12 distinct soft matter morphologies at micro‐ and nano‐scale. These structures range from spheroids, rods, fibers, ribbons, and dendricolloids, to sheets. Systematic understanding of fluid templating enables robust control over the resulting micro‐ and macro‐structures, which can be produced from a broad variety of (bio) polymers.