Direct- ink- write cross- linkable bottlebrush block copolymers for on- the- fly control of structural color

• 成果类型: Article
• 署名作者: Jeon, Sanghyun; Kamble, Yash Laxman; Kang, Haisu; Shi, Jiachun; Wade, Matthew A.; Patel, Bijal B.; Pan, Tianyuan; Rogers, Simon A.; Sing, Charles E.; Guironnet, Damien; Diao, Ying
• 署名单位: University of Illinois System; University of Illinois Urbana-Champaign; University of Illinois System; University of Illinois Urbana-Champaign; University of Illinois System; University of Illinois Urbana-Champaign; University of Illinois System; University of Illinois Urbana-Champaign
• 刊物名称: PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
• ISSN/ISSBN: 0027-9568
• DOI: 10.1073/pnas.2313617121
• 发表日期: 2024-02-27
• 关键词: photonic crystals; post-functionalization; click chemistry; polymers; polymerization; dependence; conformation; polystyrene; segregation; stiffness

摘要

Additive manufacturing capable of controlling and dynamically modulating structures down to the nanoscopic scale remains challenging. By marrying additive manufacturing with self- assembly, we develop a UV (ultra- violet)- assisted direct ink write approach for on- the- fly modulation of structural color by programming the assembly kinetics through photo- cross- linking. We design a photo- cross- linkable bottlebrush block copolymer solution as a printing ink that exhibits vibrant structural color (i.e., photonic properties) due to the nanoscopic lamellar structures formed post extrusion. By dynamically modulating UV- light irradiance during printing, we can program the color of the printed material to access a broad spectrum of visible light with a single ink while also creating color gradients not previously possible. We unveil the mechanism of this approach using a combination of coarse- grained simulations, rheological measurements, and structural characterizations. Central to the assembly mechanism is the matching of the cross- linking timescale with the assembly timescale, which leads to kinetic trapping of the assembly process that evolves structural color from blue to red driven by solvent evaporation. This strategy of integrating cross- linking chemistry and out- of- equilibrium processing opens an avenue for spatiotemporal control of self- assembled nanostructures during additive manufacturing.