Dielectric Properties of Castor Oil Derived Polymer Filled With Sol-Gel Derived Strontium Barium Niobate (Sr0.3Ba0.7Nb2O6) Ferroelectric Powder

摘要

Sol-gel derived strontium barium niobate (Sr0.3Ba0.7Nb2O6) (SBN) nanocrystalline powder was homogeneously dispersed in castor oil derived resinous polymer to develop a polymer nanocomposite. The main objective of this work was to develop a large surface area flexible polymeric material having desired mechanical, dielectric, and pyroelectric properties for use in pyroelectric detectors. Sol-gel synthesized nanocrystalline SBN powder was characterized using X-ray diffraction, FTIR, and Raman spectroscopy to study their structure. These powders were used to fabricate a ceramic as well as a polymer nanocomposite, which were then characterized for their morphological, thermal, and dielectric behavior using SEM, DSC-TGA, and Agilent LCR meter, respectively. Dielectric constant of unfilled polymer at room temperature and at all frequencies was found to be around 16-18, which steadily increased with increasing temperature. However, when filled with SBN powder, the resulting polymer nanocomposite showed an increase in the dielectric constant and attained a value of 20-30 at room temperature, which further increased with increasing temperature. For SBN ceramic, the value obtained for epsilon'(max) (dielectric constant at T-c = 250 degrees C) was around 600 (at 1 kHz) and similar to 2000 (at 100 Hz). (C) 2015 Society of Plastics Engineers