Effects of Regioregularity of π‐Conjugated Polymers Composed of Boron β‐Diketiminate on Their Stimuli‐Responsive Luminescence

• Published in: Macromolecular chemistry and physics Vol. 223; no. 9
• Main Authors: Ito, Shunichiro, Fukuyama, Misuzu, Tanaka, Kazuo, Chujo, Yoshiki
• Format: Journal Article
• Language: English
• Published: Weinheim Wiley Subscription Services, Inc 01.05.2022
• Subjects: Boron; boron complexes; Couplings; Density functional theory; Luminescence; Polymers; stimuli responsiveness; Thermal analysis; π‐conjugated polymers
• ISSN: 1022-1352; 1521-3935
• DOI: 10.1002/macp.202100504

π‐Conjugated polymers composed of a boron β‐diketiminate complex with different regioregularity are synthesized by using Suzuki–Miyaura and Yamamoto couplings. The films formed with the polymers show luminescence chromism upon exposure to solvent vapors. Most importantly, the chromic behavior depends on the regioregularity of the polymers. Wide‐angle X‐ray diffraction, thermal analysis, and density functional theory calculations suggest that the chromism can originate from the morphological change in the films and the alternation of the electronic nature of the main chains. Regioregularity of luminescent polymers composed of boron β‐diketiminate complexes affects their chromic properties. Vapochromic luminescence is clearly observed only from the films of a regioregular polymer rather than regiorandom and regiosymmetric polymers. It is indicated that the crystallinity highly depends on the regioregularity. Head‐to‐head and tail‐to‐tail linkages in the regiorandom and regiosymmetric polymers play an important role as exciton traps.