Developing the dielectric mechanisms of polyetherimide/multiwalled carbon nanotube/(Ba0.8Sr0.2)(Ti0.9Zr0.1)O3 composites
1 Department of Chemical and Materials Engineering, National University of Kaohsiung, Kaohsiung, 81148, Republic of China
2 Department of Electronic Engineering, Kao Yuan University, Kaohsiung, 82151, Republic of China
Nanoscale Research Letters 2012, 7:132 doi:10.1186/1556-276X-7-132Published: 16 February 2012
Various amounts of multiwalled carbon nanotubes [MWNTs] were embedded into polyetherimide [PEI] to form PEI/MWNT composites, and their dielectric properties were measured at 1 MHz. The Lichtenecker mixing rule was used to find a reasonable dielectric constant for the MWNTs used in this study. The dielectric constants of the developed composites were significantly increased, and the loss tangents were significantly decreased as 2.0 wt.% (Ba0.8Sr0.2)(Ti0.9Zr0.1)O3 ceramic powder [BSTZ] was added to the PEI/MWNTs to form PEI/MWNT/BSTZ composites. The Lichtenecker and Yamada mixing rules were used to predict the dielectric constants of the PEI/MWNT and PEI/MWNT/BSTZ composites. Equivalent electrical conduction models of both composites were established using the two mixing rules. In addition, the theoretical bases of the two mixing rules were used to explain the measured results for the PEI/MWNT and PEI/BSTZ/MWNT composites.