Piezoelectric properties of poly(vinylidene fluoride) and carbon nanotube blends: beta-phase development.
In order to get poly(vinylidene fluoride) (PVDF) films containing high beta-phase content, multiwalled carbon nanotubes (MWCNTs) were blended with PVDF. For drawn samples, the content of piezoelectric beta-form crystal was increased with MWCNT addition due to the rapid crystallization rate offered by the nucleating action of MWCNT, but soon reached a plateau. Poling on the drawn samples helps additional beta-phase formation when the added MWCNT content was less than 0.2 wt%; at this MWCNT amount, almost pure beta-phase crystal was obtained. More MWCNT addition induced depolarization to reduce the beta-phase content. Undrawn samples show monotonous increase of beta-phase content with MWCNT amount when subjected to poling.
Kim
Gwang Ho
GH
Hybrid Materials Research Center, Korea Institute of Science and Technology, Seoul, Korea.
Hong
Soon Man
SM
Seo
Yongsok
Y