scholarly journals α-Oxyalkylation of Quinolinium Perchlorates in the Presence of Ammonium Peroxydisulfate

1980 ◽  
Vol 2 (3) ◽  
pp. 331-337
Author(s):  
Hiroshi NODA ◽  
Masao MlNEMOTO ◽  
Makoto NISHIKAWA ◽  
Masatomo HAMANA
Keyword(s):  
Ammonium Peroxydisulfate

The role of acidity profile in the nanotubular growth of polyaniline

2010 ◽  
Vol 64 (1) ◽  
Author(s):  
Elena Konyushenko ◽  
Miroslava Trchová ◽  
Jaroslav Stejskal ◽  
Irina Sapurina
Keyword(s):  
Acetic Acid ◽  
Sulfuric Acid ◽  
Reaction Temperature ◽  
Subsequent Growth ◽  
Subsequent Oxidation ◽  
Ammonium Peroxydisulfate ◽  
Aniline Oligomers ◽  
Positive Effect ◽  
Granular Morphology

AbstractConditions of polyaniline (PANI) nanotubes preparation were analyzed. Aniline was oxidized with ammonium peroxydisulfate in 0.4 M acetic acid. There are two subsequent oxidation steps and the products were collected after each of them. At pH > 3, neutral aniline molecules are oxidized to non-conducting aniline oligomers. These produce templates for the subsequent growth of PANI nanotubes, which takes place preferably at pH 2–3. At pH < 2, granular morphology of the conducting PANI is obtained. High final acidity of the medium should be avoided in the preparation of nanotubes, e.g., by reducing the amount of sulfuric acid which is a by-product. Reduction of the peroxydisulfate-to-aniline mole ratio was tested for this purpose in the present study. Lowering of the reaction temperature from 20°C to −4°C had a positive effect on the formation of nanotubes.

Polyaniline: Thin films and colloidal dispersions (IUPAC Technical Report)

2005 ◽  
Vol 77 (5) ◽  
pp. 815-826 ◽  
Author(s):  
Jaroslav Stejskal ◽  
Irina Sapurina
Keyword(s):  
Thin Films ◽  
Dispersion Polymerization ◽  
Average Particle Size ◽  
Colloidal Dispersions ◽  
Water Soluble ◽  
Average Particle ◽  
Water Soluble Polymer ◽  
Ammonium Peroxydisulfate ◽  
Technical Report

Several workers from various institutions in six countries have prepared thin films and colloidal polyaniline dispersions. The films were produced in situ on glass supports during the oxidation of anilinium chloride with ammonium peroxydisulfate in water. The average thickness of the films, assessed by optical absorption, was 125 ± 9 nm, and the conductivity of films was 2.6 ± 0.7 S cm–1. Films prepared in 1 mol l–1 HCl had a similar thickness, 109 ± 10 nm, but a higher conductivity, 18.8 ± 7.1 S cm–1. Colloidal polyaniline particles stabilized with a water-soluble polymer, poly(N-vinylpyrrolidone) [poly(1-vinylpyrrolidin-2-one)], have been prepared by dispersion polymerization. The average particle size, 241 ± 50 nm, and polydispersity, 0.26 ± 0.12, have been determined by dynamic light scattering. The preparation of these two supramolecular polyaniline forms was found to be well reproducible.

scholarly journals The Preparation of a Highly Stretchable Cellulose Nanowhisker Nanocomposite Hydrogel

2015 ◽  
Vol 2015 ◽  
pp. 1-8 ◽  
Author(s):  
Jiufang Duan ◽  
Jianxin Jiang ◽  
Jianzhang Li ◽  
Liujun Liu ◽  
Yiqiang Li ◽  
...  
Keyword(s):  
Room Temperature ◽  
Nanocomposite Hydrogel ◽  
Cellulose Nanowhiskers ◽  
Composite Hydrogels ◽  
Ammonium Peroxydisulfate ◽  
Cellulose Nanowhisker ◽  
Stearyl Methacrylate ◽  
Highly Stretchable ◽  
Cross Links ◽  
Scanning Electron

Molecules that associate to form cross-links by hydrophobic association are designed and synthesised. Hydrogels, based on cellulose nanowhiskers (CNWs), acrylamide (AM), and stearyl methacrylate (C18), were synthesised by micellar copolymerisation, using ammonium peroxydisulfate as an initiator. CNWs composite hydrogels were characterised by Fourier transform infrared spectroscopy (FTIR) and their morphologies were investigated by scanning electron microscope (SEM). The system shows the original extensibility up to about 2500%: the tensile strength and compressive strength have maximum values of 1.338 MPa and 2.835 MPa, respectively. Besides excellent mechanical properties, CNWs composite hydrogels also have the ability to self-heal and remould: this is mainly attributed to the dissociation and reassociation of the associated micelles. In contrast to conventional cellulose hydrogels, these systems, when broken or cut, can be simply repaired by bringing together fractured surfaces to self-heal at room temperature.

Formation of nanostructured polyaniline by dopant-free oxidation of aniline in a water/isopropanol mixture

2014 ◽  
Vol 68 (3) ◽  
Author(s):  
Aleksandra Rakić ◽  
Marija Vukomanović ◽  
Gordana Ćirić-Marjanović
Keyword(s):  
Molecular Structure ◽  
Reaction Medium ◽  
Enthalpy Of Mixing ◽  
Conductivity Measurements ◽  
Reaction Conditions ◽  
Electron Microscopies ◽  
Ammonium Peroxydisulfate ◽  
Transmission Electron ◽  
Structure Morphology ◽  
Free Oxidation

AbstractNanostructured polyaniline (PANI) was synthesised by the oxidation of aniline in a water/ isopropanol (propan-2-ol, IPA) (50 vol. %) mixture, without added acid, using ammonium peroxydisulfate (APS) as an oxidant. Influence of the IPA co-solvent and the reaction time on the molecular structure, morphology and properties of synthesised PANI samples was studied by FTIR, Raman, and UV-VIS spectroscopies, scanning and transmission electron microscopies (SEM and TEM), and conductivity measurements. The course of the reaction was followed by monitoring changes in the temperature and acidity of the reaction medium. The results were compared with those obtained for PANI prepared in water without IPA under the same reaction conditions. The importance of the solvation effects, dielectric constant of the solvent, and the enthalpy of mixing of IPA with water on the course of the polymerisation reaction and on the properties of polymeric products in the water/IPA medium in comparison with those in water was pointed out.

Investigation of the Structural Change of Doped Polyaniline during Heat Treatment

2009 ◽  
Vol 87-88 ◽  
pp. 311-316 ◽  
Author(s):  
Hui Huang ◽  
Zhong Cheng Guo
Keyword(s):  
Crystal Structure ◽  
Heat Treatment ◽  
Acidic Medium ◽  
Structural Changes ◽  
Oxidative Polymerization ◽  
Chemical Oxidative Polymerization ◽  
Ammonium Peroxydisulfate ◽  
Heat Treated ◽  
Doped Polyaniline ◽  
Aqueous Acidic Medium

Doped polyaniline (PANI) was synthesized by chemical oxidative polymerization of aniline in aqueous acidic medium with mixed sulfuric acid and 5-sulfosalcyclic acid as complex dopant , and ammonium peroxydisulfate as an oxidant, and heat treated at 150°C, 200°C, 250°Cand 300°C for 2 hours in vacuum. Different intrinsic and extrinsic structural changes due to heat treatment were determined from FTIR and XRD measurements. When PANI is subjected to heat treatment, different changes are taking place in the system like doping, dedoping (extrinsic), oxidation and changes in crystal structure (intrinsic). Mechanisms for doping, dedoping and oxidation, are proposed.

scholarly journals Electrical Conductivity Studies of Polyaniline Nanotubes Doped with Different Sulfonic Acids

2013 ◽  
Vol 2013 ◽  
pp. 1-7 ◽  
Author(s):  
Mohd. Khalid ◽  
Milton A. Tumelero ◽  
Iuri. S. Brandt ◽  
Vinicius C. Zoldan ◽  
Jose J. S. Acuña ◽  
...  
Keyword(s):  
Electrical Conductivity ◽  
Cyclic Voltammetry ◽  
Oxidative Polymerization ◽  
Sulfonic Acids ◽  
Camphorsulfonic Acid ◽  
Ammonium Peroxydisulfate ◽  
Toluenesulfonic Acid ◽  
Sem And Tem ◽  
Self Assembled ◽  
Polyaniline Nanotubes

Self-assembled polyaniline (PANI) nanotubes were prepared in the presence of three different sulfonic acids as dopant, namely, p-toluenesulfonic acid, camphorsulfonic acid, and tetrakis(4-sulfonatophenyl)porphyrin, by oxidative polymerization using ammonium peroxydisulfate as the oxidant. The morphology of the PANI nanotubes was determined by SEM and TEM and the electrical conductivity was measured as a function of temperature. The PANI nanotubes were also characterized by FTIR, XRD, UV-Vis, and cyclic voltammetry. We have found that the dopants had a noteworthy effect on the electrical conductivity whithout significant changes in the morphology of the PANI nanotubes.

Polyaniline-coated cellulose fibers decorated with silver nanoparticles

2008 ◽  
Vol 62 (2) ◽  
Author(s):  
Jaroslav Stejskal ◽  
Miroslava Trchová ◽  
Jana Kovářová ◽  
Jan Prokeš ◽  
Mária Omastová
Keyword(s):  
Silver Nanoparticles ◽  
Thermogravimetric Analysis ◽  
Aspect Ratio ◽  
Percolation Threshold ◽  
Silver Nitrate ◽  
Cellulose Fibers ◽  
Subsequent Reaction ◽  
Aniline Hydrochloride ◽  
Ammonium Peroxydisulfate ◽  
Average Size

AbstractCellulose fibers of 20 μm in diameter and aspect ratio of 2 or 10 were coated with protonated polyaniline (PANI) during the oxidation of aniline hydrochloride with ammonium peroxydisulfate in an aqueous medium. The presence of PANI has been proved by FTIR spectroscopy. The conductivity increased from 4.0 × 10−14 S cm−1 to 0.41 S cm−1 after coating the fibers with PANI. The percolation threshold in the mixture of original uncoated and PANI-coated fibers was reduced from 10 mass % PANI to 6 mass % PANI, as the aspect ratio changed from 2 to 10. The subsequent reaction with silver nitrate results in the decoration of PANI-coated cellulose fibers with silver nanoparticles of about 50 nm average size. The content of silver of up to 10.6 mass % was determined as a residue in thermogravimetric analysis. FTIR spectra suggest that the protonated emeraldine coating changed to the pernigraniline form during the latter process and, consequently, the conductivity of the composite was reduced to 4.1 × 10−4 S cm−1, despite the presence of silver.

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