Related Experiment Video
Updated: Apr 21, 2026
06:34
Application of a Coupling Agent to Improve the Dielectric Properties of Polymer-Based Nanocomposites
Published on: September 19, 2020
6.5K
Core-shell nanoparticles and enhanced polarization in polymer based nanocomposite dielectrics
Amoghavarsha Mahadevegowda1, Neil P Young, Patrick S Grant
1Department of Materials, University of Oxford, Parks Road, Oxford, OX1 3PH, UK.
Nanotechnology
|November 8, 2014
Summary
We studied aluminium-aluminium oxide core-shell nanoparticles in polymer dielectrics. The nanostructure
Area of Science:
- Materials Science
- Polymer Nanocomposites
- Dielectric Materials
Background:
- Polymer nanocomposites (PNCs) are crucial for advanced dielectric applications.
- Understanding nanoparticle behavior within polymer matrices is key to enhancing material properties.
Purpose of the Study:
- To investigate the evolution and nature of metallic core-oxide shell nanoparticles.
- To elucidate the role of nanostructure in enhanced polarization within polymer-nanocomposite dielectrics.
Main Methods:
- Fabrication of Nylon-6 based PNCs with aluminium (core)-aluminium oxide (shell) nanoparticles using vacuum deposition.
- Characterization of nanoparticle structure and chemistry using transmission electron microscopy.
Main Results:
- Core-shell structure formation was observed in aluminium-aluminium oxide nanoparticles.
- The aluminium oxide shell was found to be highly defective, strained, and non-stoichiometric.
- High polarizability in PNCs was directly linked to the core-shell structure's characteristics.
Conclusions:
- The specific nanostructure of aluminium-aluminium oxide core-shell particles significantly influences dielectric properties.
- Defects and non-stoichiometry in the oxide shell play a critical role in enhancing polarization.
- This study provides insights into designing advanced dielectric materials with tailored nanoparticle structures.
Related Concept Videos
01:29Potential Due to a Polarized Object
943
A neutral atom consists of a positively charged nucleus surrounded by a negatively charged electron cloud. When placed in an external electric field, the external electric force pulls the electrons and nucleus apart, opposite to the intrinsic attraction between the nucleus and the electrons. The opposing forces balance each other with a slight shift between the center of masses of the nucleus and the electron cloud, resulting in a polarized atom. On the other hand, a few molecules, like water,...
943
01:31Dielectric Polarization in a Capacitor
6.8K
The presence of a dielectric medium in a capacitor not only changes the voltage and capacitance but also affects the electric field. In general, dielectrics can be of two types: polar and nonpolar. In a polar dielectric, the positive and negative charges in the molecules are separated by a distance and hence have a permanent dipole moment. In contrast, no such charge separation exists in a nonpolar dielectric, however the nonpolar molecules get polarized in the presence of an external electric...
6.8K
01:26Susceptibility, Permittivity and Dielectric Constant
3.7K
When placed in an external electric field, a dielectric material gets polarized. The charge density in the dielectric material is given by the sum of the bound and free charge densities, while the total charge density can also be written in terms of the total electric field. The bound charge density can be measured in terms of polarization, leading to the relationship between electric displacement and polarization.
3.7K
02:34Polymers
44.0K
The word polymer is derived from the Greek words “poly” which means “many” and “mer” which means “parts”. Polymers are long chains of molecules composed of repeating units of smaller molecules, known as monomers. They either occur naturally, such as DNA and proteins, or can be constructed synthetically, like plastics. They have varied structural characteristics, such as linear chains, branched chains, or complex networks, that contribute to the...
44.0K
02:34Polymers
23.6K
23.6K
02:34Polymers
37.1K
37.1K