Enhanced piezoelectric responses and crystalline arrangement of electroactive polyvinylidene fluoride/magnetite nanocomposites

Abstract

ABSTRACTThe well distributed and electroactive polyvinylidene fluoride (PVDF)/magnetite nanocomposites were successfully fabricated using a mixed solvent system (THF/DMF). Dynamic mechanical properties of the fabricated PVDF/magnetite nanocomposites indicate significant enhancements in the storage modulus as compared with that of neat PVDF. By adding 2 wt % magnetite nanoparticles into the PVDF matrix, the thermal stability of nanocomposites could be enhanced about 26°C as compared with that of PVDF. The β‐phase fraction of PVDF is significantly enhanced with increasing the voltage of electric field poling. The piezoelectric responses of PVDF/magnetite films are extensively increased about five times in magnitude with applied strength of electrical field at 35 MV/m. The change of piezoelectric responses during the applied electric field may be due to the relative long arrangement of PVDF units along the direction of electric field poling and thus increases the values of Lp* and lc. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40941.