聚氨酯/钛酸铜镧钠复合材料的制备及介电性研究

Study on the preparation and dielectric property of polyurethane/sodium copper lanthanum titanate composite

采用溶胶-凝胶法制备了钛酸铜镧钠Na_(0.5)La_(0.5)Cu_3Ti_4O_(12)(NLCTO)陶瓷粉末填料。以聚氨酯(PU)材料为基体,采用原位聚合方法,制备了PU/NLCTO复合材料。利用红外光谱仪、X射线衍射仪、扫描电子显微镜、阻抗分析仪对复合材料的结构和性能进行了研究。结果表明:随着NLCTO陶瓷粉体含量增加,复合材料的介电常数和电导率相应地增大,但其介电损耗在一定的频率范围内变化不大。当NLCTO质量分数达到30%时,复合材料的介电常数在100 Hz下达到64.5,是聚氨酯基体的5倍;在10 k Hz下达到22,是聚氨酯基体的7.5倍。

The Na0.5La0.5Cu3Ti4O12(NLCTO)ceramics powders were prepared by the sol-gel method. The PU/NLCTO composites were prepared by situ polymerization using polyurethane(PU) as the matrix. The structure and properties of PU/NLCTO composite were investigated by FT-IR spectra and scanning electron microscope(SEM),X-Ray Diffraction(XRD)and impedance. The results showed that the dielectric constant and conductivity were increased with the increasing of NLCTO content,but its dielectric loss did not change much within a certain frequency range. Filled with 30 wt % NLCTO,the dielectric constant of the composite reaehed 64. 5 at 100 Hz and 22 at 10 k Hz,respectively,which were 5 and 7. 5 times that of the polyurethane matrix.