F. H. Muhammad

Electrical Studies On Hexanoyl Chitosan‐based Nanocomposite Polymer Electrolytes

Hexanoyl chitosan‐based nanocomposite polymer electrolytes were prepared using solution casting technique. The effect of addition of nanosize titanium oxide, TiO2 as the filler on the electrical properties of the prepared electrolyte system was investigated by impedance spectroscopy. The maximum conductivity of 3.06×10−4 S cm−1 was achieved with addition of 6 wt%. TiO2 which is 1 order of magnitude higher than the filler‐free electrolyte sample (σ = 1.83×10−5 S cm−1). The Rice and Roth model was proposed to explain the conductivity variation for the prepared electrolyte system. The ac conductivity of hexanoyl chitosan‐based nanocomposite electrolytes was also analyzed.

Transport properties of hexanoyl chitosan-LiClO4-TiO2 composite polymer electrolyte

The solution casting technique has been employed to prepare hexanoyl chitosan-LiClO4 and hexanoyl chitosan-LiClO4-TiO2 electrolyte films. The highest room temperature conductivity of 1.9 × 10−5 S cm−1 is achieved at 30 wt% LiClO4. This conductivity value is further increased to 3 × 10−4 S cm−1 when 6 wt% of TiO2 was added. The variation in conductivity as a function of LiClO4 and TiO2 concentration has been understood on the basis of number of ionic charge carriers. In order to elucidate the conductivity mechanism brought about by the TiO2, diffusivity of ionic charge carriers were calculated.

Miscibility study of hexanoyl chitosan in blend with epoxidized natural rubber by viscometric analysis

Miscibility of blends of hexanoyl chitosan and epoxidized natural rubber with 25 mol% epoxidation level (ENR25) was investigated by dilute solution viscometry (DSV). Experimental results obey the Huggins’ equation in the concentration range under investigation. Intrinsic viscosities are found to vary linearly with blend composition. The difference between experimental and ideal Huggins coefficients, κ=K12−K1⋅K2 is proposed to evaluate the miscibility behavior of the blends. Negative deviations from the ideal behavior indicated immiscibility between hexanoyl chitosan and ENR25.

Effect of Filler Type on the Electrical Properties of Hexanoyl Chitosan-Based Polymer Electrolytes

A preliminary investigation of polymer electrolyte based on hexanoyl chitosan, lithium perchlorate (LiClO4) and various filler additives are described in this paper. Hexanoyl chitosan-based nanocomposite polymer electrolytes were prepared using solution casting technique. The effect of filler addition and type of filler on the electrical properties of the prepared electrolyte system was investigated by impedance spectroscopy (IS). The maximum conductivity of 3.06 × 10-4 S cm-1 and 1.96 × 10-4 S cm-1 were achieved for the hexanoyl chitosan-LiClO4-TiO2 and hexanoyl chitosan-LiClO4-SiO2 electrolyte system, respectively. The variations in conductivity observed were discussed quantitatively using the Rice and Roth model from which the concentration of free ions and their mobility were calculated.

Structural and Electrical Characterization of Hexanoyl Chitosan-LiClO4-TiO2-DMC Polymer Electrolytes

Hexanoyl chitosan-based polymer electrolytes were prepared using the solution casting technique. The effect of dimethyl carbonate (DMC) plasticizer on the structural and electrical properties of the prepared electrolyte system was investigated by X-ray diffraction and impedance spectroscopy, respectively. Upon addition of 15 wt. % of DMC, the ionic conductivity was increased to 4.09 x 10-4 S cm-1 from 3.06 x 10-4 S cm-1. The XRD results revealed the variation in conductivity from the structural aspect. For example, sample with lower crystallinity exhibits higher conductivity. The Rice and Roth model was employed to understand the variation in conductivity on the basis of number and mobility of free ions.

Effect of Anion Size on the Conductivity Behaviour of Hexanoyl Chitosan-Based Polymer Electrolytes

Films of hexanoyl chitosan containing lithium perchlorate (LiClO4) or lithium triflouromethanesulfonate (LiCF3SO3) were prepared by solution casting technique. The effect of anion size on the conductivity behaviour of hexanoyl chitosan has been investigated. The conductivity of 4.15 × 10-7 S/cm and 4.07 × 10-6 S/cm were achieved for the hexanoyl chitosan-LiClO4 and hexanoyl chitosan-LiCF3SO3 electrolyte system at 50wt.% of salt concentration, respectively. The Rice and Roth model was used to analysis quantitatively the obtained conductivity trends for the prepared electrolyte systems. The diffusion coefficients of cations and anions were calculated from the conductivity and transference number measurements. This is followed by the discussion on the diffusion coefficients of ClO4- and CF3SO3- anion.

Structural and electrical studies of hexanoyl chitosan based electrolyte system

Abstract Hexanoyl chitosan based nanocomposite polymer electrolytes were prepared using solution casting technique. The effect of TiO2 addition on the structural and electrical properties of the prepared electrolyte system was investigated by impedance spectroscopy and X-ray diffraction. The conductivity of the filler free polymer electrolyte is 1·83×10−5 S cm−1, whereas with the addition of 6 wt-%TiO2, the conductivity increased by 1 order of magnitude to 3·06×10−4 S cm−1. The Rice and Roth model was proposed to explain the conductivity variation for the prepared electrolyte system. The increase in conductivity could be attributed to the increase in the number and mobility of free ions.

Characterisation of Al2O3 doped hexanoyl chitosan–LiCF3SO3–EC polymer electrolytes

Abstract The insolubility of chitosan in a wide range of organic solvents has limited the application of chitosan especially in electrochemical systems. In order to improve its solubility, acyl modification of chitosan was carried out in the present study. Films of hexanoyl chitosan-based polymer electrolyte were prepared by solution casting technique. The effect of filler on the transport properties of hexanoyl chitosan–LiCF3SO3–ethylene carbonate electrolytes has been investigated. The conductivity for fillerfree polymer electrolyte is 2·75 × 10–5 S cm–1. The addition of 6 wt-%Al2O3 increased the conductivity by one order of magnitude to 1·01 × 10–4 S cm–1. Within the temperature range investigated, the conductivity of the polymer electrolytes are thermally assisted and can be described by Arrhenius law. The conductivity variant has been justified via the Rice and Roth model in which the number of free ions per unit volume, mobility and diffusion coefficient of free ions were obtained.