Graft Copolymerization Of Aniline Research Articles

Ammonium Persulphate Initiated Graft Copolymerization of Aniline onto Chitosan-A Comparative Kinetic Study

Ammonium persulphate (APS) has been used as efficient initiator for graft copolymerization of the aniline (ANI) onto chitosan at 25±0.1°C. Graft copolymerization of ANI onto chitosan has taken place through the cation radical initiation process. The grafting parameters have been evaluated by varying concentration of ANI, APS and chitosan. The effects of concentration of APS, ANI, chitosan and reaction time on graft copolymerization were studied by determining the grafting percentage (%G), grafting efficiency (%E) and percentage add-on. It was observed that bout rate of homopolymerization (Rh) and rate of graft coplymerization (Rg) increased with the increase in concentration of each component. On the basis of the experimental observations, initiating steps have been proposed and a suitable rate expression for graft copolymerization has been derived. Electrical conductivity of grafted polyaniline (PANI) onto chitosan (Chit-g-PANI, chitaline) was measured by the four probe method.

Preparation of polyaniline nanomatrix formed in natural rubber

Natural rubber-grafted polyaniline with a nanomatrix structure was prepared and characterized. The graft copolymerization of aniline on natural rubber was performed in the latex stage. Factorial experimental design and univariate experiments were used to evaluate the effect of the factors on the conversion of aniline in the graft copolymerization. The structure of the products was characterized through 1H-NMR spectroscopy. The thermal properties, electrical conductivity, and morphology of the products were investigated. The results from the factorial experimental design showed that reaction temperature was the most important factor affecting the conversion, pH was the next most important, and the other factors were relatively unimportant. Polyaniline was confirmed to graft onto natural rubber and form a nanomatrix structure in the resulting material. The thermal properties and electrical conductivity of natural rubber-grafted polyaniline with a nanomatrix structure were improved compared to those of a polyaniline/natural rubber blend with an island-matrix structure. Natural rubber-grafted-polyaniline with nanomatrix structure was prepared through graft-copolymerization. The effect of parameters on the graft-copolymerization was investigated using factorial experimental design and univariate experiments. The structural characterization of the resulting materials through NMR spectroscopy confirmed that aniline was grafted on the natural rubber. As observed in TEM image, polyaniline, which covered the natural rubber particles, formed the nanomatrix, and natural rubber particles formed the dispersed phase. The thermal properties and electrical conductivity of natural rubber-grafted-polyaniline were improved by the formation of nanomatrix structure.

Preparation of Graphene-Polyaniline-Cellulose Double Network Hydrogels Using One Pot Method by Gamma Irradiation with Electrochemical Properties

In order to achieve high performance of electrochemical properties, numerous efforts have been devoted to the development of advanced multi-component hybrid double network hydrogel materials. In this research, the double network hydrogels were synthesized using one pot method by graft copolymerization of aniline onto graphene and cellulose using gamma irradiation as initiator. The formation of the double network hydrogels was confirmed by the Fourier Transform Infrared Spectroscopy (FTIR) study. X-ray Diffraction (XRD) analysis showed that the crystalline was increased through graft copolymerization graphene-aniline-cellulose double network. It was found that the crosslink density increased with increasing aniline volume and increasing radiation doses inversely with the swelling degree. Electrochemical measurements exhibited that increasing aniline volume and radiation doses increased specific capacitance and conductivity of the hydrogels. When compared with the pure graphene, the synthesized double network hydrogels exhibits remarkably enhanced specific capacitance of 9.774 F g-1 and conductivity i.e. 4.766 x 10-2 Scm-1 in 0.5 M HCl solution at aniline volume 8 mL and radiation dose 80 kGy. The improved electrochemical properties of the double network hydrogels represented an alternative promising candidate for the application as energy storage devices and offered a new facile method.

Chemical and electrochemical grafting of polyaniline onto poly(vinyl chloride): synthesis, characterization, and materials properties

We have designed and developed a new strategy for the chemical and electrochemical graft copolymerization of aniline onto poly(vinyl chloride). For this purpose, first phenylamine groups were incorporated into poly(vinyl chloride) via a nucleophilic substitution reaction in the presence of a solvent composed of 4-aminophenol, potassium carbonate, and dry N,N-dimethylformamide at room temperature, in order to avoid cross-linking. The macromonomer obtained was used in chemical and electrochemical oxidation copolymerization with aniline monomer to yield a poly(vinyl chloride)-g-polyaniline (PVC-g-PANI) graft copolymer. The chemical structures of samples as representatives were characterized by means of Fourier transform infrared and 1H nuclear magnetic resonance spectroscopies. The electroactivity behaviors of the synthesized samples were verified under cyclic voltammetric conditions. The electrical conductivity and electroactivity measurements showed that the PVC-g-PANI graft copolymer has lower electrical conductivity as well as electroactivity than those of the pure PANI. However, the lower electrical conductivity and electroactivity levels in this material can be improved at the price of solubility and processability. Moreover, the thermal behavior and chemical composition of the synthesized graft copolymer were investigated. Copyright © 2016 John Wiley & Sons, Ltd.

Peroxydisulfate initiated graft copolymerization of aniline onto poly(propylene) fiber?A kinetic approach

A novel method for the preparation of electrically conducting fibers through chemical grafting of electrically conducting polymer onto poly(propylene) (PP) fiber is described. The graft copolymerization of aniline (ANI) was performed in aqueous acidic medium by using a chemical oxidant such as peroxydisulfate (PDS). Grafting occurred with simultaneous homopolymer formation. The content of polyaniline in the backbone fiber was found to vary by varying [monomer], [initiator], and amount of PP fiber. Various graft parameters such as rate of grafting (Rg), % grafting, and % grafting efficiency were evaluated. The rate of homopolymerization (Rh) was also determined. Both Rh and Rg showed first-order dependency on [ANI], [PDS], and amount of PP fiber variation. The chemical grafting was confirmed by use of cyclic voltammetry and conductivity measurements. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 3827–3834, 2003

Modification of Textile Fibers

Peroxy disulphate initiated graft copolymerization of aniline onto poly(ethylene-terephthalate) and nylon6 fibre was carried out under nitrogen atmosphere at various experimental conditions in aqueous acidic medium. Graft parameters such as % grafting, % efficiency and rate of graft copolymerization were determined. Grafting was always accompanied by homopolymer formation. The rate of homopolymerization was also followed in all experimental conditions. The chemical grafting was confirmed by FTIR spectroscopy, differential thermal analysis and conductivity measurements. Probable mechanism has been proposed to explain our experimental results.

Peroxomonosulphate initiated graft copolymerization of aniline onto poly(propylene) fibre - A kinetic approach

Graft copolymerization of poly(aniline) (PANI) onto poly(propylene) (PP) fibre was carried out in aqueous acidic medium under nitrogen atmosphere by using peroxomonosulphate (PMS) as a lone initiator. The non-conducting fibre was now made into a conducting one through the chemical grafting of PANI units onto the PP fibre backbone. The content of PANI in the backbone was found to vary while varying the [ANI], [PMS] and amount of PP fibre. Various graft parameters were evaluated. The chemical grafting of PANI onto PP fibre was confirmed by conductivity measurements.

Peroxosalts initiated graft copolymerization of aniline onto wool fibre—a comparative kinetic study

Chemical grafting of aniline (ANI) onto wool fibre was carried out in aqueous acidic medium by using peroxosalts such as peroxodisulphate (PDS) and peroxomonosulphate (PMS) as an initiator for various [Monomer], [Initiator] and (fibre weight). It was observed that both Rh and Rg increased with increase in the concentration of each component. The chemical grafting was confirmed using FTIR spectroscopy, cyclic voltammetry (CV) and conductivity measurements.