Dielectric response of conducting carbon-black-filled ethylene-octene copolymer microcellular foams

Dielectric response of conducting carbon‐black‐filled ethylene–octene copolymer microcellular foams has been investigated with variation of blowing agent and filler loading in the frequency range of 100 Hz to 5 MHz and temperature range from 30 to 100°C. With increase in blowing agent loading, the d...

Full description

Saved in:
Bibliographic Details
Published in:Polymer composites 2016-12, Vol.37 (12), p.3398-3410
Main Authors: Das, Suchilipsa, Achary, Patnala Ganga Raju, Nayak, Nimai C., Choudhary, Ram Narayan Prasad
Format: Article
Language:English
Subjects:
Blowing agents
Capacitance
Carbon
Copolymers
Dielectrics
Grain boundaries
Mathematical models
Microcellular foams
Relaxation time
Temperature
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Dielectric response of conducting carbon‐black‐filled ethylene–octene copolymer microcellular foams has been investigated with variation of blowing agent and filler loading in the frequency range of 100 Hz to 5 MHz and temperature range from 30 to 100°C. With increase in blowing agent loading, the dielectric permittivity increases for both unfilled as well as carbon‐black‐filled microcellular foams. The experimental complex impedance plots were compared with model‐fitted plots obtained by taking an equivalent circuit of (CQR) (CR).The values of Rb (bulk resistance), Rgb (grain boundary resistance), bulk capacitance (Cb), and grain boundary capacitance (Cgb) at different temperatures were calculated and compared with experimental values. The relaxation time due to bulk effect (τb) has been calculated from relaxation frequency (fr). The dc conductivity (σdc) decreases with rise in temperature indicating the existence of positive temperature coefficient of resistance in the material. The activation energy (Ea) calculated from the relaxation time due to bulk effect (τb) was found to be 0.446 eV, whereas it was 0.363 eV from the dc conductivity plot in the temperature range of 30–100°C. POLYM. COMPOS., 37:3398–3410, 2016. © 2015 Society of Plastics Engineers
ISSN:0272-8397
1548-0569
DOI:10.1002/pc.23538