Synthesis and characterization of processable polyaniline doped with novel dopant NaSIPA

Abstract

Aniline has been polymerized in the presence of a novel dopant sodio-5-sulfo-isophthallic acid (NaSIPA), via the chemical oxidative polymerization route. The thermal stability and processability of polyaniline prepared by indirect method (PD1) have been improved significantly (2908C) as compared to polyaniline doped with conventional inorganic dopants like HCl or H 2 SO 4 , without much loss of electronic conductivity (5.07 S/cm in PD1). This suggests its use for melt blending with engineering thermoplastics. However, polyaniline prepared by direct method (PD2) can be melt-blended only with conventional thermoplastics like polyethylene, polypropylene, polystyrene, etc. Low-temperature studies reveal the 1-D variable range hopping as a conduction mechanism for direct polymer (PD2), with parameters T o and r o as 4112 K and 15.1 S/cm, respectively. However, for indirectly doped polymer (PD1) Arrhenius-type model, having parameters |(E F 2 E C )| and r C as 0.04 eV and 28.4 S/cm, respectively, it suited well. The coherence length as found from XRD data was around 28.8 nm for PD1 and 25.2 nm for PD2.

Structural and dielectric properties of CuCl2 and ZnCl2 doped polyaniline

“…Conducting polymers have widely been investigated in the last two decades due to their unique electrical properties and potential applications in various electronic devices, such as sensors, light emitting diodes, and rechargeable batteries [1–17]. Among the conducting polymers, polyaniline (PANI) is one of the most popular for its easy synthesis, high electrical conductivity, and good environmental stability [1, 3, 6–10, 12–37]. PANI is available in four different forms, such as leucoemeraldine base (colorless), emeraldine base (blue), pernigraniline base (violet), and emeraldine salt (green) depending on the pH of the solution and oxidation potential out of which only emeraldine salt (or protonated emeraldine) is electrically conducting.…”

Property of polyaniline /multi-wall carbon nanotube composites

“…The band at 1106 em" is assigned to the N=Q=N bond. It reflects the degree of electronic delocalization over the polymer backbone and it is characteristic of polyaniline conductivity [19,20]. The band near 800 em" is due to C-H bonds outside of the deformation plane ofpara-di-substituted benzene [14].…”

Conducting polyaniline nanorods doped with aromatic carboxyl chain end functionalized polystyrene

“…Moreover, an efficient method for the preparation of a series of polyaniline derivatives with nanofibre, nanotube, nanowire and nanosphere morphology has been developed by the chemical oxidative polymerization of aniline via an emulsion polymerization process in the presence of an organic carboxylic acid as dopant and surfactant [55]. However, the incorporation of small inorganic acids and simple sulphonic and carboxylic acids dopants into the polymer matrix of the conducting PANI derivative results in the loss of dopant from the matrix at high processing temperature which ultimately leads to the loss of electrical conductivity and change in the morphology of the PANI derivative [42][43][44][45][46][47][48][49][50][51][52][53][54][55]. Thus, the use of polymeric acids as dopants in the chemical oxidative polymerization of aniline leads to improved morphological control, eliminates dopant volatility, retains the electrical conductivity and promotes the processibility of the final doped PANI derivative.…”

“…In addition, PANI derivatives doped with simple aliphatic and aromatic carboxylic acids, hydroxyl acids and amino acids affords the preparation of a wide variety of PANI morphological structures ranging from microspheres and microplatelets to nanofibres and nanotubes [42][43][44][45][46][47][48][49][50][51][52][53][54][55]. Moreover, an efficient method for the preparation of a series of polyaniline derivatives with nanofibre, nanotube, nanowire and nanosphere morphology has been developed by the chemical oxidative polymerization of aniline via an emulsion polymerization process in the presence of an organic carboxylic acid as dopant and surfactant [55].…”