Construction of Circularly Polarized Blue Luminescent Spherulites through Hierarchical Self-Organization of Ionic Conjugated Polymer Assemblies

2014 Fiscal Year Final Research Report

• Project/Area Number: 25620098
• Research Category: Grant-in-Aid for Challenging Exploratory Research
• Allocation Type: Multi-year Fund
• Research Field: Polymer chemistry
• Research Institution: Kyoto University
• Principal Investigator: AKAGI Kazuo 京都大学, 工学(系)研究科(研究院), 教授 (20150964)
• Project Period (FY): 2013-04-01 – 2015-03-31
• Keywords: 高分子球晶 / イオン性共役ポリマー / 階層的自己組織化 / 円偏光発光 / ヘリカル会合体 / π-π相互作用 / イオン相互作用 / ポリパラフェにレン誘導体

Outline of Final Research Achievements

A cationic π-conjugated polymer is synthesized by introducing tetraalkylammonium groups onto both side chains of poly(para-phenylene) (PPP). An anionic axially chiral binaphthyl derivative (BNP) is also synthesized by introducing two anionic sulfonate groups onto the 2 and 2’positions of the binaphthyl ring. PPP and BNP form a hierarchically self-organized assembly with an interchain helically π-stacked structure stabilized by both electrostatic and π-π interactions. The assembly shows large dissymmetry factors on the order of 0.1 in the absorption and luminescence spectra, even in solution. The assembly forms spheres with an average size of 220 nm and the spheres show a Maltese Cross and extinction rings in the polarized optical microscope. Furthermore, the spheres exhibit a circularly polarized blue luminescence. It is thus demonstrated that the spheres are semicrystalline spherulites constructed from helically π-stacked assemblies of PPP-BNP.

Free Research Field

化学・複合化学・機能性高分子