Space charge effects on the dielectric response of polymer nanocomposites
Abstract
Adding high-κ ceramic nanoparticles into polymers is a general strategy to improve the performances in energy storage. Classic effective medium theories may fail to predict the effective permittivity in polymer nanocomposites wherein the space charge effects are important. In this work, a computational model is developed to understand the space charge effects on the frequency-dependent dielectric properties including the real permittivity and the loss for polymer nanocomposites with both randomly distributed and aggregated nanoparticle fillers. It is found that the real permittivity of the SrTiO3/polyethylene (12% SrTiO3 in volume fraction) nanocomposite can be increased to as high as 60 when there is nanoparticle aggregation and the ion concentration in the bulk polymer is around 1016 cm–3. This model can be employed to quantitatively predict the frequency-dependent dielectric properties for polymer nanocomposites with arbitrary microstructures.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Aug 28, 2017
- Source ID
- 10.1063/1.4991079
Entities
People
- Ce-wen Nan
- Jian-Jun Wang
- Long-Qing Chen
- Xin Zhang
- Yang Shen
- Yuanhua Lin
- Zhong-hui Shen
Organizations
- Air Force Office of Scientific Research
- National Natural Science Foundation of China
- Pennsylvania State University
- Program 973
- Tsinghua University