Enhanced dielectric properties of polymer matrix composites with BaTiO3 and MWCNT hybrid fillers using simple phase separation
Enhanced dielectric properties of polymer matrix composites with BaTiO3 and MWCNT hybrid fillers using simple phase separation
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DOI：
10.1016/j.nanoen.2016.10.033
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发表时间：
2016-12-01
期刊：
影响因子：
17.6
通讯作者：
Gerhardt, Rosario A.
中科院分区：
文献类型：
--
作者：
Jin, Youngho;Xia, Ning;Gerhardt, Rosario A.
采用混相-非混相凝聚-热压法制备了铁电纳米钛酸钡(BT)与多壁碳纳米管(MWCNT)复合的聚偏氟乙烯(PVDF)基杂化纳米复合材料。扫描电子显微镜照片显示陶瓷纳米颗粒分布良好，颗粒团聚很小。导电的MWCNT作为铁电纳米粒子的极化电荷传输相，提高了基质聚合物的电荷存储能力，而少量的MWNTs则阻止了导电网络的形成。这种简单的加工方法使得复合材料在很宽的频率范围内(10-1 MHz)具有高的实际介电常数和低的介电损耗。通过优化铁电相的电荷存储行为和导电相的电荷传输行为之间的协同效应，改善了含杂化填料的聚合物基纳米复合材料(含和不含碳纳米管)的介电性能。当BaTiO_3的体积分数为37.1%，碳纳米管的体积分数为3%时，复合材料的介电常数和介电损耗的最佳组合分别为71.7%和0.045。除了获得可靠的介电性能外，纳米复合材料还表现出灵活性，使这些复合材料有可能用于许多柔性电子设备和静电储能设备。
Poly (vinylidene fluoride) (PVDF) matrix hybrid nanocomposites, featuring ferroelectric barium titanate (BT) nanoparticles and multi-walled carbon nanotubes (MWCNT) embedded in the polymer, were fabricated by a miscible-immiscible coagulation method followed by hot pressing. SEM images showed good distribution of the ceramic nanoparticles with very little particle agglomeration. The conductive MWCNT increased the charge storage ability of the matrix polymer by serving as a polarized charge transport phase for the ferroelectric nanoparticles, while the small MWNT amounts used prevented the formation of conductive networks. The simple processing method utilized resulted in composites with high real permittivity and low dielectric loss over a wide range of frequency (10-1 MHz). The dielectric properties of the polymer matrix nanocomposites with hybrid fillers (BT with and without MWNT) were improved by optimizing the synergistic effects between the charge storage behavior of the ferroelectric phase and the charge transport behavior of the conductive phase. The best combination of real permittivity and dielectric loss properties (71.7 and 0.045 respectively) were obtained for the nanocomposites containing 37.1 vol% of BaTiO3 and 3 vol% of MWCNT. In addition to achieving reliable dielectric properties, the nanocomposites also displayed flexibility making these composites potentially useful for many flexible electronic devices and electrostatic energy storage devices.