Photoinduced protonation of polyaniline assisted by hydrogen-bonding materials

• Published in: Synthetic metals 2011-07, Vol.161 (13), p.1420-1423
• Main Authors: Shi, Zheng, Johns, Valentine K., Alber, Candace, Liao, Yi
• Format: Article
• Language: English
• Subjects: Applied sciences; Conductivity; Exact sciences and technology; Hydrogen bonding; Hydrogen bonds; Irradiation; Photo-acid generator; Physicochemistry of polymers; Poly(vinyl alcohol); Polyaniline; Polyanilines; Polymers and radiations; Polyvinyl alcohols; Properties and characterization; Protonation; Reproducibility
• ISSN: 0379-6779; 1879-3290
• DOI: 10.1016/j.synthmet.2011.05.013

► Photo-induced conductivity of polyaniline/photo-acid generator composites was investigated. ► Addition of polyvinyl alcohol to the composites increased the photo-induced conductivity. ► A hydrogen-bonding photo-acid generator increased the conductivity from 10 −5 S cm −1 to 10 −1 S cm −1. ► Hydrogen bonding assists proton transfer in the irradiated composites. Composites of the emeraldine base form of polyaniline (PANI-EB) and photo-acid generators (PAGs) increase their conductivities upon photo-irradiation due to protonation of PANI-EB. Such materials may be utilized to fabricate conducting patterns by photo-irradiation. However, the conductivity obtained by direct irradiation of PANI-EB/PAG composites was normally quite low, and conductivity above 10 −3 S cm −1 often required post-treatment with HCl. In this work, poly(vinyl alcohol) (PVA), which can form a hydrogen bonding network, was added to PANI-EB/PAG. Results showed that PVA enhanced film quality, conductivity and reproducibility. Photo-induced conductivity of 10 −2 S cm −1 was obtained when the ratio of PANI-EB/PVA/PAG was 1:1:0.6. A novel PAG, bis(p-hydroxyphenyl)phenylsulfoniumtriflate [(PhOH) 2PhS + OTf −], which can form hydrogen bonds with PANI was synthesized and mixed with PANI-EB. A composite of PANI-EB and the PAG with a ratio of 1:0.5 achieved a conductivity of 10 −1 S cm −1 after irradiation. However, the initial conductivity before irradiation was as high as 10 −5 S cm −1 due to relatively high acidity of the PAG.