**Author details**

**Figure 16.** Dielectric constant and conductivity for pure PVDF matrix and the dispersed phase, NaNbO3 with different

**Figure 15.** Dielectric constant and conductivity for the various fractions mass of fibers–PAni*rep* dispersed phase in

The morphology of the dispersed phase directly influences this behavior; the fibers compared with cubes as shown in Figure 16 allow for better charge distribution and thus a higher conductivity. The surface-modified fibers with a conductive polymer, in this case PAni, promote conductivity and permittivity (dielectric constant). The values found for the dielectric constant and conductivity decrease in the order fibers–PAni*rep*, fiber, cubes. The same result is observed for the percolation threshold values, when these materials are used as the dispersed

By microwave hydrothermal synthesis, it is possible to obtain Na2Nb2O6.nH2O and NaNbO3 orthorhombic crystalline structure particles. The Na2Nb2O6.nH2O is obtained in fiber-like morphology while NaNbO3 presented cubic-like morphology. The results are associated to synthesis conditions including synthesis time and microwave power. Using 300 W, the increase

phase in the PVDF matrix, indicating that these factors are interrelated.

morphology (cubes, fiber and fiber–PAni*rep*).

PVDF matrix. Inset for the best linear fit of the percolation threshold.

78 Ferroelectric Materials – Synthesis and Characterization

**4. Conclusion**

Guilhermina F. Teixeira1 , Rafael A. Ciola1 , Walter K. Sakamoto2 and Maria A. Zaghete1\*

\*Address all correspondence to: zaghete@iq.unesp.br

1 Department of Biochemistry and Chemistry Technology, Chemistry Institute, São Paulo State University – UNESP, Araraquara, Brazil

2 Department of Physics and Chemistry, School of Engineering, São Paulo State University, UNESP, Ilha Solteira, Brazil
