Structural and morphological characterization of chloride salt of conducting poly(o-methoxyaniline) obtained at different time synthesis

Emeraldine-salt poly(o-methoxyaniline) form (ES-POMA) was chemically synthesized at time synthesis ranging from 0.5 to 72 h and characterized by X-ray Diffraction (XRD), LeBail fit, Small-angle X-ray Diffraction (SAXD), Small-angle X-ray Scattering (SAXS) and Scanning Electron Microscopy (SEM). Crystallinity and crystal data (for 3 h of synthesis, a = 7.0073 Å, b = 10.6078 Å, c = 22.5234 Å, α = 83.3783°, β = 84.7231° and γ = 89.0455°) were obtained by XRD and showed that the percentage of crystallinity increased from 48% to 63%. LeBail fit showed that the crystallites have lost their globular shape to give rise to twinned crystallites shape ranging from 26 to 56 Å. By SAXS it was obtained the particle Guinier Radius of Giration (Rg) of (310 ± 1)Å. The maximum particle size (Dmax) of synthesized polymers was obtained from the pair-distance distribution function (p(r)) and ranged from 1000 to 830 Å. SEM images showed a globular vesicular morphology with micrometric sizes. It was observed that increasing time synthesis promotes the size reduction of these structures with the electrical conductivity of the samples increasing from 5.18 × 10−7 to 8.89 × 10−7 S/cm.

► It was showed that the time synthesis improved the polymer crystallinity.
► The use of SAXD/XRD to obtain the full diffractogram for ES-POMA is a new topic in literature.
► The use of SAXS and XRD provide a systematic study on the structural characterization of polymers.
► LeBail fit represents a recent tool applied in structural researches of polymer materials.