Large‐scale synthesis of polyaniline nanofibers based on renewable resource molecular template

Abstract

We report reproducible large‐scale synthesis of polyaniline (PANI) nanofibers up to 100 g scale via micelle mediated soft template approach. A unique built‐in amphiphilic azobenzenesulfonic acid based on renewable resource dopant was synthesized for large‐scale production of PANI nanofibres. The amphiphilic surfactant exists as 4.3 nm micelle in water and it self‐organized with aniline to form long cylindrical aggregates, which template for PANI nanofibers. The PANI nanofibers were found soluble in water and organic solvents and they were characterized by 1H‐NMR, FT‐IR, and viscosity techniques. The mechanism of the PANI nanofiber formation was investigated by dynamic light scattering, scanning electron microscopy, and high resolution transmission electron microscopy. The width of the nanofibers was precisely controlled from 130–200 nm with length up to ∼ 5 μm. The absorption spectroscopic analysis of nanofibers in water revealed that the large‐scale samples (10, 50, and 100 g) were found to posses expanded chain conformation compared to that of 1 g scale sample. The wide angle X‐ray diffraction patterns showed two new peaks at lower angles at d spacing of 25.5 and 13.6 Å corresponding to lamellar ordering of PANI chains followed by interdigitation of the amphiphilic dopant in the nanofibers.