Abdelghani Benyoucef

A conducting nanocomposite via intercalative polymerisation of 2-methylaniline with aniline in montmorillonite cation-exchanged

Polymer/montmorillonite nanocomposites were prepared. Intercalation of 2-methylaniline with aniline monomers into montmorillonite modified by cation was followed by subsequent oxidative polymerization of the monomers in the interlayer spacing. The clay was prepared by cation exchange process between sodium cation in (M-Na) and copper cation (M-Cu). We prepared a series of polymer/clay nanocomposite materials that consisted of an emeraldine base of poly(2-MA), poly(2-MA-co-ANI) and PANI by layered copper montmorillonite. All organic monomers used were first intercalated into the interlayer regions of clay hosts followed by a one-step in situ oxidative polymerization. The unique properties of the as-synthesized nanocomposites materials are investigated by electronic conductivity measurements, X-ray diffraction, FTIR spectroscopy, UV-vis spectroscopy, thermogravimetric analysis and SEM, were also studied by cyclic voltammetry which indicates the electroactive effect of nanocomposite gradually increased with aniline in the polymer chain.

Preparation and characterization of the new conducting composites obtained from 2-methylaniline and aniline with activated carbon by in situ intercalative oxidative polymerization

AbstractA simple method was used to synthesize poly(2-methylaniline), poly(2-methylaniline-co-aniline) and polyaniline composites with activated carbon (AC) using in situ adsorption oxidative polymerization. The resultant polymer/activated carbon composites were characterized by UV-visible (UV-vis), Fourier transform infrared (FTIR), thermal gravimetric analysis (TGA) and X-ray diffraction (XRD). The UV-vis and FTIR studies showed that AC particles affect the quinoid units along the polymer backbone and indicate strong interactions between AC particles and quinoidal sites of polymers. In addition, the room temperature conductivity values of these composites varied between 0.256 and 11.196 S cm−1. The electrochemical behavior of the polymers extracted from the composites has been analyzed by cyclic voltammetry. Good electrochemical response has been observed for polymer films; the observed redox processes indicate that the polymerization into AC produces electroactive polymers.

Removal of 8-quinolinecarboxylic acid pesticide from aqueous solution by adsorption on activated montmorillonites.

Sodium montmorillonite (Na-M), acidic montmorillonite (H-M), and organo-acidic montmorillonite (Org-H-M) were applied to remove the herbicide 8-quinolinecarboxylic acid (8-QCA). The montmorillonites containing adsorbed 8-QCA were investigated by transmission electron microscopy, FT-IR spectroscopy, X-ray diffraction analysis, X-ray fluorescence thermogravimetric analysis, and physical adsorption of gases. Experiments showed that the amount of adsorbed 8-QCA increased at lower pH, reaching a maximum at pH 2. The adsorption kinetics was found to follow the pseudo-second-order kinetic model. The Langmuir model provided the best correlation of experimental data for adsorption equilibria. The adsorption of 8-QCA decreased in the order Org-H-M > H-M > Na-M. Isotherms were also used to obtain the thermodynamic parameters. The negative values of ΔG indicated the spontaneous nature of the adsorption process.

Polyaniline/Montmorillonite Nanocomposites Obtained by In Situ Intercalation and Oxidative Polymerization in Cationic Modified-Clay (Sodium, Copper and Iron)

Polyaniline/montmorillonite nanocomposites (PANI/M) were obtained by intercalation of aniline monomer into M modified with different cations and subsequent oxidative polymerization of the aniline. The modified-clay was prepared by ion exchange of sodium, copper and iron cations in the clay (Na–M, Cu–M and Fe–M respectively). Infrared spectroscopy confirms the electrostatic interaction between the oxidized PANI and the negatively charged surface of the clay. X-ray diffraction analysis provides structural information of the prepared materials. The nanocomposites were characterized by transmission electron microscopy and their thermal degradation was investigated by thermogravimetric analysis. The weight loss suggests that the PANI chains in the nanocomposites have higher thermal stability than pure PANI. The electrical conductivity of the nanocomposites increased between 12 and 24 times with respect to the pure M and this increase was dependent on the cation-modification. The electrochemical behavior of the polymers extracted from the nanocomposites was studied by cyclic voltammetry and a good electrochemical response was observed.