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Title: Tunable structural color of bottlebrush block copolymers through direct-write 3D printing from solution
Additive manufacturing of functional materials is limited by control of microstructure and assembly at the nanoscale. In this work, we integrate nonequilibrium self-assembly with direct-write three-dimensional (3D) printing to prepare bottlebrush block copolymer (BBCP) photonic crystals (PCs) with tunable structure color. After varying deposition conditions during printing of a single ink solution, peak reflected wavelength for BBCP PCs span a range of 403 to 626 nm (blue to red), corresponding to an estimated change in d-spacing of >70 nm (Bragg- Snell equation). Physical characterization confirms that these vivid optical effects are underpinned by tuning of lamellar domain spacing, which we attribute to modulation of polymer conformation. Using in situ optical microscopy and solvent-vapor annealing, we identify kinetic trapping of metastable microstructures during printing as the mechanism for domain size control. More generally, we present a robust processing scheme with potential for on-the-fly property tuning of a variety of functional materials.  more » « less
Award ID(s):
1727605 1847828
PAR ID:
10195236
Author(s) / Creator(s):
; ; ; ; ; ;
Date Published:
Journal Name:
Science Advances
Volume:
6
Issue:
24
ISSN:
2375-2548
Page Range / eLocation ID:
eaaz7202
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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