超声辅助PP/云母片介电复合材料的制备与性能

Preparation and Properties of Ultrasonic Assisted PP/Mica Sheet Dielectric Composites

通过超声波辅助法将云母片分散在聚丙烯(PP)基体中,然后通过熔融共混法制备不同组分的 PP/云母片复合材料。对复合材料的微观形貌和结构进行表征,研究了 PP/云母片复合材料的力学性能、介电性能、击穿强度和储能密度。结果表明,超声波辅助法一定程度上有助于云母片的剥离和分散。当云母片含量为 5%时,复合材料的拉伸强度和断裂伸长率达到最大,分别为 38.8 MPa 和 30%。此时材料的介电性能也达到最佳,击穿强度为 362 MV/m;储能密度为 1.46 J/cm^3,相比于 PP 纯样增长了 51%。由于云母片和 PP 的协同效应,复合材料的介电损耗也维持在较低水平,低于 0.05。

The mica was dispersed in polypropylene (PP) matrix by ultrasound-assisted method,and then PP/mica composites with different components were prepared by melt blending method. The microstructure and morphology of the composites were characterized. The mechanical properties,dielectric properties,breakdown strength and energy storage density of PP/mica composites were studied. The results show that the ultrasonic assisted method is helpful to the separation and dispersion of mica. When the content of mica nanosheet is 5%,the tensile strength and elongation at break of the composite reach the maximum, which are 38.8 MPa and 30%,respectively. At this time,the dielectric properties of the material also surpass that of counterparts, the breakdown strength is 362 MV/m;and the energy storage density is 1.46 J/cm^3,which is 51% higher than that of pure PP. Due to the synergistic effect of mica sheet and PP,the dielectric loss of the composite is also maintained at a low level,lower than 0.05.