Synthesis and Heavy‐Metal‐Ion Sorption of Pure Sulfophenylenediamine Copolymer Nanoparticles with Intrinsic Conductivity and Stability

Abstract

Novel copolymer nanoparticles were easily synthesized with a polymerization yield of 59.3 % by an oxidative precipitation polymerization of aniline (AN) and m‐sulfophenylenediamine (SP) in HCl without any external stabilizer. The polymerization yield, size, morphology, electroconductivity, solubility, solvatochromism, lead and mercury ion adsorbability of the HCl‐doped copolymer salt particles were studied by changing the AN/SP ratio. The AN/SP (80:20) copolymer particles are found to have the minimal number‐average diameter(84.4 nm), minimal size polydispersity index (1.149), high stability, good long‐term stability, powerful redispersibility in water, high purity, and clean surface because of a complete elimination of the contamination from external stabilizer. The copolymer salts possess a remarkably enhanced solubility, interesting solvatochromism, and widely adjustable electroconductivity moving across nine orders of magnitudes from 10−9 to 10 0 S cm−1. The AN/SP (70:30) copolymer particles have the highest Hg 2+ adsorbance and adsorptivity of 497.7 mg g−1 and 98.8 %, respectively, which are much higher values than those of other materials. The sorption mechanism of lead and mercury ions on the particles is proposed. The copolymer bases with 5–10 mol % SP unit show excellent film formability, flexibility, and smooth appearance. The copolymer should be very useful in the fabrication of cost‐effective conductive nanocomposite with low percolation threshold and in removal of toxic metallic ions from waste water.