TY - JOUR
T1 - Single walled carbon nanotube (SWNT)-polyimide nanocomposites as electrostrictive materials
AU - Deshmukh, Sujay
AU - Ounaies, Zoubeida
N1 - Funding Information:
The authors wish to thank Mr. Chris Call for his help in thickness strain measurements using the fiber optic sensor. The authors would also like to acknowledge financial support from the National Science Foundation (NSF) under grant number CMMI-0514265 and from NASA Langley Research Center under grant number NCC1-02013.
PY - 2009/10
Y1 - 2009/10
N2 - The combination of properties offered by polymer nanocomposites provides opportunities for going beyond structural reinforcement where engineered electroactive responses and enhanced electrical and dielectric properties would result in multifunctionality. In our study, we show that adding single walled carbon nanotubes (SWNTs) to a non-actuating polyimide (PI) can create an electromechanical actuation response in the nanocomposite. The neat polyimide does not show any actuation response under an applied electric field, whereas the SWNT-PI composites above the percolation threshold exhibit an electrostrictive behavior that is highly dependent on SWNT content. Both bending and thickness-extension strains are obtained at very low electric field magnitudes; the study also evaluates the effect of applied electric field magnitude, frequency and SWNT content on the actuation strain and strain rate. Dielectric spectroscopy and thermally stimulated current measurements reveal an enhanced polarization in the presence of SWNTs. This enhancement is key to the actuation mechanism and is thought to arise from a combination of three sources: SWNTs acting as extended electrodes within the polymer, interfacial polarization and noncovalent interactions between the SWNTs and the polymer.
AB - The combination of properties offered by polymer nanocomposites provides opportunities for going beyond structural reinforcement where engineered electroactive responses and enhanced electrical and dielectric properties would result in multifunctionality. In our study, we show that adding single walled carbon nanotubes (SWNTs) to a non-actuating polyimide (PI) can create an electromechanical actuation response in the nanocomposite. The neat polyimide does not show any actuation response under an applied electric field, whereas the SWNT-PI composites above the percolation threshold exhibit an electrostrictive behavior that is highly dependent on SWNT content. Both bending and thickness-extension strains are obtained at very low electric field magnitudes; the study also evaluates the effect of applied electric field magnitude, frequency and SWNT content on the actuation strain and strain rate. Dielectric spectroscopy and thermally stimulated current measurements reveal an enhanced polarization in the presence of SWNTs. This enhancement is key to the actuation mechanism and is thought to arise from a combination of three sources: SWNTs acting as extended electrodes within the polymer, interfacial polarization and noncovalent interactions between the SWNTs and the polymer.
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U2 - 10.1016/j.sna.2009.07.007
DO - 10.1016/j.sna.2009.07.007
M3 - Article
AN - SCOPUS:71749121766
SN - 0924-4247
VL - 155
SP - 246
EP - 252
JO - Sensors and Actuators, A: Physical
JF - Sensors and Actuators, A: Physical
IS - 2
ER -