Thermal Stability and Magnetic Properties of Polyvinylidene Fluoride/Magnetite Nanocomposites.

Zen-Wei Ouyang,Tzong-Ming Wu,Erh-Chiang Chen

doi:10.3390/ma8074553

Abstract

This work describes the thermal stability and magnetic properties of polyvinylidene fluoride (PVDF)/magnetite nanocomposites fabricated using the solution mixing technique. The image of transmission electron microscopy for PVDF/magnetite nanocomposites reveals that the 13 nm magnetite nanoparticles are well distributed in PVDF matrix. The electroactive β-phase and piezoelectric responses of PVDF/magnetite nanocomposites are increased as the loading of magnetite nanoparticles increases. 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 magnetic properties of PVDF/magnetite nanocomposites exhibit supermagnetism with saturation magnetization in the range of 1.6 × 10−3–3.1 × 10−3 emu/g, which increases as the amount of magnetite nanoparticles increases. The incorporation of 2 wt % magnetite nanoparticles into the PVDF matrix improves the thermal stability about 25 °C as compared to that of PVDF. The effect of magnetite particles on the isothermal degradation behavior of PVDF is also investigated.

Highlights

Polyvinylidene fluoride (PVDF) has received considerable interest due to its exceptional ferroelectric and piezoelectric properties [1,2]
This study describes the thermal stability and magnetic properties of polyvinylidene fluoride (PVDF)/magnetite composites fabricated using solution mixing process
Structural and morphological analysis using transmission electron microscopy showed that the 13 nm magnetite nanoparticles are uniformly distributed in PVDF matrix

Summary

Introduction

Polyvinylidene fluoride (PVDF) has received considerable interest due to its exceptional ferroelectric and piezoelectric properties [1,2]. The crystalline structure of PVDF is significantly determined by the processing, thermal, or mechanical treatments that the polymer undergoes. Another approach has been reported to obtain the electroactive β-phase of PVDF, including the use of BaTiO3, TiO2, clay, hydrated ionic salt, or ferrite nanoparticles to fabricate the polymer nanocomposites [11,12,13,14,15,16,17,18,19,20,21]. The incorporation of 6 nm Fe3O4 nanoparticles into PVDF can improve the mechanical and piezoelectric properties of nanocomposites [23]. The piezoelectric properties of samples poled with various applied strengths of electrical field were measured

Materials

Synthesis of Monodispersed Magnetite Nanoparticles

Results and Discussion

Conclusions