Tuning the Color of Photonic Glass Pigments by Thermal Annealing

Advanced Materials, Journal Year: 2022, Volume and Issue: 35(34)

Published: Dec. 9, 2022

Thermal or solvent annealing is commonly employed to enhance phase separation and remove defects in block copolymer (BCP) films, leading well-resolved nanostructures. Annealing of particular importance for photonic BCP materials, where large, well-ordered lamellar domains are required generate strong reflections at visible wavelengths. However, such strategies have not been considered porous systems, as inverse glasses, the structure (and thus optical response) no longer defined solely by chemical compatibility blocks, but size arrangement voids within matrix. In this study, a demonstration how concept "thermal annealing" can be applied bottlebrush (BBCP) microparticles with glass architecture presented, enabling their coloration tuned from blue red. By comparing biocompatible BBCPs similar composition, different thermal behavior, it shown that process driven both temperature-induced softening BBCP matrix (i.e., polymer mobility) absence microphase (enabling diffusion-induced swelling pores). Last, toward production thermochromic patterned hydrogel, exemplifying potential responsive photonic-glass pigments smart labeling anticounterfeiting applications.

Language: Английский

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Nanocomposite hydrogels for strain sensing based on optical and electrical signals: a review

Chemical Communications, Journal Year: 2023, Volume and Issue: 59(58), P. 8894 - 8910

Published: Jan. 1, 2023

This minireview summarizes strain sensing functions of nanocomposite hydrogels by focusing on optical and electrical responses. Appropriate embedding nanostructures or nanomaterials in yield improvements their performances.

Language: Английский

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Dynamic Photonic Janus Colloids with Axially Stacked Structural Layers

ACS Nano, Journal Year: 2024, Volume and Issue: 18(6), P. 5196 - 5205

Published: Feb. 2, 2024

Diblock copolymer (dBCP) particles capable of dynamic shape and color changes have gained significant attention due to their versatility in programmable shapes intricate nanostructures. However, application photonic systems remains limited challenges achieving a sufficient number defect-free layers over tens-of-micrometer scale. In this study, we present pioneering demonstration dBCP featuring 300 axially stacked with responsive color- shape-transforming capabilities. Our approach leverages the complex interplay between macrophase separation multiple incompatible components microphase from solvent-evaporative microemulsions. Specifically, continuous phase silicone oil polystyrene-block-poly(2-vinylpyridine) (PS-b-P2VP), triggered by solvent evaporation, promotes anisotropic growth PS-b-P2VP layers. This results formation Janus colloids, where an droplet merges nanostructured polymer cone lamellar structures align along long axis cone. We highlight capability precisely adjust particle morphology corresponding orientation, dispersion, structural window modulating both molecular weight volume ratio oil. Furthermore, reversible swelling/deswelling colloids is visualized correlated colors. Finally, demonstrate potential study presenting multicolor-patterned array highlighting possibilities for applications smart ink devices.

Language: Английский

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Self-Assembly of Hierarchical High-χ Fluorinated Block Copolymers with an Orthogonal Smectic-within-Lamellae 3 nm Sublattice and Vertical Surface Orientation

ACS Nano, Journal Year: 2024, Volume and Issue: 18(17), P. 11311 - 11322

Published: April 16, 2024

Hierarchical structure-within-structure assemblies offer a route toward increasingly complex and multifunctional materials while pushing the limits of block copolymer self-assembly. We present detailed study self-assembly series fluorinated high-χ copolymers (BCPs) prepared via postmodification single poly(styrene)-block-poly(glycidyl methacrylate) (S-b-G) parent polymer with alkylthiol pendent groups containing 1, 6, or 8 carbons (termed trifluoro-ethanethiol (TFET), perfluoro-octylthiol (PFOT), perfluoro-decylthiol (PFDT), respectively). Bulk X-ray scattering thermally annealed samples demonstrates hierarchical molecular assembly phase separation between two blocks within block. The degree ordering is highly sensitive to synthetic variation; lamellar sublattice was formed for S-b-GPFOT S-b-GPFDT. Thermal analyses reveal that exhibits liquid crystal-like ordering. thin-film behavior an investigated using real-space (atomic force microscopy scanning electron microscopy) reciprocal-space (resonant soft (RSoXS), grazing incidence small- wide-angle scattering) measurements. After thermal annealing in nitrogen vacuum, films thicker than 1.5 times primary lattice spacing exhibit 90-degree grain boundary, exposing thin layer vertical lamellae at free interface, exhibiting horizontal on preferential (polystyrene brush) substrate. RSoXS measurements near-perfect orthogonality orientations, demonstrating patterning nanoscale.

Language: Английский

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High-Performance Flow Chemistry Platform for Scalable Continuous Synthesis of Branched Block Copolymers with Precise Chain Structures

Chinese Journal of Polymer Science, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 17, 2025

Language: Английский

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