Conducting polymer composites are useful in many applications such as sensors, EMI shielding, etc. In this report a composite of Nylon-6 (Ny-6) polymer doped with copper(II) chloride (CuCl2) is used to prepare the nanofibers by electrospinning. The electrospun nanofibers were characterized by IR spectra and the surface morphology is studied using scanning electron microscopy (SEM). An average diameter of the nanofibers is estimated to be 54 nm. Nanofibers of Ny-6 are prepared with different levels of doping of CuCl2 (10, 20, 30 and 40 wt%). DC resistance, AC impedance and capacitance measurements in the frequency range of 105-107 Hz are carried out on the nanofibers at room temperature. The results of these measurements are discussed. © 2007 Elsevier B.V. All rights reserved.

Vemuri Rama Krishna Murthy

Capacitance

Conducting polymers

Copper compounds

Doping (additives)

Electric Impedance

electrospinning

infrared spectroscopy

Nylon polymers

DC RESISTANCE

NYLON-6

POLYMER NANOFIBERS

Nanofibers

IIT Madras is a public technical and research university located in Chennai, Tamil Nadu. Founded in 1959, it is recognised as an Institute of National Importance.

IIT Madras has been ranked as the top engineering institute in India for four years in a row by the National Institutional Ranking Framework of the MHRD

It currently offers undergraduate, postgraduate and research degrees across 16 disciplines in Engineering, Sciences, Humanities and Management. About 596 faculty belonging to science and engineering departments and centres of the Institute are engaged in teaching, research and industrial consultancy.

IIT Madras

Materials Science and Engineering B: Solid-State Materials for Advanced Technology

Aligned nanocomposite electrospun fibers are investigated for electrical (dc, ac, and dielectric) and thermal properties (10-40 wt.). This nanocomposite consists of poly(methylmethacrylate) (PMMA) grafted core-shell magnetite (CSM) nanoparticles and PMMA. Electrical properties as a function of tunnel gap (in between the CSM nanoparticles) are studied as the polymer shell stays intact and the cores do not touch each other well above the percolation threshold. The depleted improvement in dc conductivity ( dcwt) with increasing wt. (the improvement percentage: dc10 to dc20 ≈ 100; dc20 to dc30 ≈ 40 and dc30 to dc40 ≈ 1.2) affirms the non-touching cores of CSM. Interestingly, the observed ac conductive behavior (0.1-13 MHz) in the high end of the frequency range is in clear contrast to that of a typical percolating system, in fact it does not explicitly follow the universal power law. Some of the obtained critical exponents are not accommodated by the universal theory and significantly different from the present theoretical/experimental predictions. Additionally, an improvement in thermal stability of ∼30 C and an overall increase in glass transition temperature are reported. © 2011 American Institute of Physics.

Fulltext

Journal of Applied Physics

Non-universal behavior well above the percolation threshold and thermal properties of core-shell-magnetite-polymer fibers

Composite nanofibers from poly(methylmethacrylate)- (PMMA-) conducting polyaniline [PANI(HCl)] were prepared by using the electrospinning technique. The morphology and structural details of the fibers were characterized by SEM and the ac conductivity of the composite fibers found was measured to be ∼ 2.17 × 10-4 S/cm which is very good enhancement compared to that of pure PMMA and conductivity of PANI-PMMA thin films as well. The conductivity is found to increase with increase in the polyaniline content in the composite. Microwave Hall mobility measurements on electrospun nanofibers showed 17 cm2/V s for the lower loadings. With further increase in the polyaniline content in the composite, the mobility value decreases which is attributed to the increase in carrier-carrier scatterings. © 2011 American Institute of Physics.

Microwave Hall mobility and electrical properties of electrospun polymer nanofibers

The specific capacitance of polyaniline (PANI) deposited potentiodynamically on a stainless steel (SS) substrate, in the presence of p-toluene sulphonic acid (PTS) is estimated. Cyclic voltammetric experiments, galvanostatic charge-discharge studies and impedance analysis are carried out in order to investigate the applicability of the system as an electrochemical supercapacitor. Fourier transform infrared (FTIR), X-ray diffraction (XRD) and scanning electron microscopy (SEM) techniques are employed for characterization of the electrode. © 2006 Elsevier B.V. All rights reserved.

Synthetic Metals

Investigation of polyaniline-coated stainless steel electrodes for electrochemical supercapacitors

The formation of continuous aligned polymer fibers using electrospinning was discussed. The fibers were characterized using optical microscopy and scanning electron microscopy. In electrospinning, electrostatic force was applied between polymer solutions or melt kept in a pipette or a syringe, and a counter metal electrode kept at a distance. Results show that the use of a single sharp pin as a counter electrode, which helps to focus the fibers due to focusing electric field configuration, helps in achieving good alignment of fibers.

Applied Physics Letters

Electrospinning of continuous aligned polymer fibers

Biomacromolecules

Changes in the Molecular Orientation and Tensile Properties of Uniaxially Drawn Cellulose Films

Biomaterials

Guided bone regeneration membrane made of polycaprolactone/calcium carbonate composite nano-fibers

Colloids and Surfaces B: Biointerfaces

Nano-fibrous scaffolds for tissue engineering

Preparation and characterization of electrospun nanofibers of Nylon-6 doped with copper(II) chloride

Journal	Materials Science and Engineering B: Solid-State Materials for Advanced Technology
ISSN	09215107
Open Access	No