Preparation and structural characterization of shear-aligned films in a high proton conductive alkyl-sulfonated polyimide with lyotropic liquid crystallinity. Issue 1 (22nd September 2021)

• Record Type: Journal Article
• Authors: Goto, Ryosuke; Ono, Yutaro; Hara, Mitsuo; Seki, Takahiro; Nagao, Yuki; Nagano, Shusaku
• Is Part Of: Molecular crystals and liquid crystals. Volume 727:Issue 1(2022)
• Page Start: 23
• Page End: 32
• Publication Date: 2021-09-22
• Subjects: Lyotropic liquid crystal -- molecular alignment -- polyimide -- proton conductive polymer electrolyte; Molecular crystals -- Periodicals; Liquid crystals -- Periodicals; Liquid crystals; Molecular crystals; Periodicals; 548
• DOI: 10.1080/15421406.2021.1946963
• Languages: English
• ISSNs: 1542-1406

Abstract

Abstract: Molecular-organized structures of polymer electrolytes have been extensively studied in recent years. Recently, we demonstrated that alkyl-sulfonated polyimide (ASPI) forms a lyotropic lamellar liquid crystalline (LC) phase under humid conditions and exhibits a high proton conductivity of 10 −1 S cm −1 in the in-plane lamella direction at 95% relative humidity. In this work, we conducted precise structural evaluations of the lyotropic LC ASPI for in-plane aligned films prepared by a bar-coating method with a concentrated solution. The ASPI concentrated solution exhibited a birefringent feature and lyotropic LC properties. Humidity-controlled in situ polarized infrared spectroscopy confirmed the in-plane anisotropic structure of the aligned film with clear dichroism, and the dichroism did not change under humidification. Humidity-controlled in situ grazing-incidence X-ray scattering measurement revealed the hierarchical LC structure with main-chain smectic ordering in the lyotropic lamella structure of the shear aligned ASPI film.