Details

Autor(en) / Beteiligte

• Kim, Jinwoo
• Park, Jinseok
• Jung, Kyunghyun
• Kim, Eun Ji
• Tan, Zhengping
• Xu, Meng
• Lee, Young Jun
• Ku, Kang Hee
• Kim, Bumjoon J.

Titel

Light-Responsive Shape- and Color-Changing Block Copolymer Particles with Fast Switching Speed

Ist Teil von

• ACS nano, 2024-03, Vol.18 (11), p.8180-8189

Ort / Verlag

United States: American Chemical Society

Erscheinungsjahr

2024

Link zum Volltext

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• Polymer particles capable of dynamic shape changes in response to light have received substantial attention in the development of intelligent multifunctional materials. In this study, we develop a light-responsive block copolymer (BCP) particle system that exhibits fast and reversible shape and color transitions. The key molecular design is the integration of spiropyran photoacid (SPPA) molecules into the BCP particle system, which enables fast and dynamic transformations of polystyrene-b-poly­(4-vinylpyridine) (PS-b-P4VP) particles in response to light. The SPPA photoisomerization, induced by 420 nm light irradiation, lowers the pH of the aqueous surroundings from 5.5 to 3.3. The protonated P4VP block substantially increases in domain size from 14 to 39 nm, resulting in significant elongation of the BCP particles (i.e., an increase in the aspect ratio (AR) of the particles from 1.8 to 3.4). Moreover, SPPA adsorbed onto the P4VP surface induces significant changes in the luminescent properties of the BCP particles via photoisomerization of SPPA. Notably, the BCP particles undergo fast, dynamic shape and color transitions within a period of 10 min, maintaining high reversibility over multiple light exposures. Functional dyes are selectively incorporated into different domains of the light-responsive BCP particles to achieve different ranges of color responses. Thus, this study showcases a light-responsive hydrogel display capable of reversible and multicolor photopatterning.