Synthesis and assessment of poly(5-nitro-2-aminophenol) as a new scaling inhibitor to control the precipitation of CaCO3 and CaSO4 in solution

Abstract

The introduction of a -NO2 substituent in o-aminophenol would create an open-unit polymer suitable for different applications. We report the synthesis of poly(5-nitro-2-aminophenol) by aniline-catalyzed oxidative polymerization. The polymer structure was intensively characterized by spectroscopic techniques, elemental analysis, cyclic voltammetry, electrical conductivity and microscopic measurements such as SEM, TEM, TGA and DSC. The hydrophilic and hydrophobic nature of the substituents provided the formation of amphiphilicity, as judged by SEM. Thermal measurements reveal high stability up to 500 °C. Electrical conductivity decreases with increasing temperature at various frequencies. This behavior reflects the semiconducting nature in the extrinsic range, which is characterized by high carriers and low mobility. Dielectric measurements have shown that permittivity decreases gradually at lower levels, mainly due to the transport of charging carriers. Investigating the copolymer as a new scale blocker has resulted in moderate to high performance attributed to the change in polymer geometry because of the presence of different tautomers having equivalent ortho functionalities and could equally coordinate with free calcium ions and thus reduce the nucleation rate and block crystal growth. Thus, the abovementioned features indicate a new potential candidate for application as a scaling inhibitor of CaSO4 and CaCO3 precipitation, a common problem in industry.

Efficient removal of safranin from aqueous solution using a new type of metalated highly self-doped polyaniline nanocomposite

“…Adsorption kinetics and isotherms studies Different kinetic models are used to analyze the experimental data of different concentrations of safranin dye (20,30,40, 50 ppm for 75 min, 25 °C, 2 g / L adsorbent dose) for copolymer 6 and nanocomposite 7 according to equations of pseudo first order and pseudo second order, discussed later in the results section. Also, Langmiur and Freuindish isotherm types were investigated for different concentrations of safranin dye for copolymer 6 and nanocomposite 7 according to its equations, discussed later in the results section.…”

“…As a part of an ongoing project directed to new findings in the field of water treatment using functionalized polyanilines as highly promising candidates [18,19,20,21], we investigated the use of (aniline-co-aniline-2,5-disulfonic acid)/L-hexuronic acid/Ag@SiO 2 nanocomposites as a new highly anionic polyelectrolyte with an enhanced adsorptive effect for removing the cationic dye safranin. The incorporation of disulfonated units into the polymer chain should double the sulfonate groups on the backbone and produce regular molecular structure polymers with a higher sulfonation degree [22].…”

Poly (aniline-co-aniline-2,5-disulfonic acid) / L-ascorbic acid / Ag@SiO2 / polysafranin nanocomposite: Synthesis, characterization and anomalous electrical behaviour

“…As part of an ongoing project directed to research in the field of using PANI and its functionalized analogues as multifunctional substrates for industrial application [21][22][23][24], we recently reported the chemical synthesis and characterization of poly(aniline-co-aniline-2,5disulfonic acid) and its composite containing L-hexuronic acid, Fig. 1, and metallic Ag/SiO2 nanoparticles, as an efficient, new, thermally stable anionic polyelectrolyte to remove safranin dye from aqueous media [25].…”