【作者】 郭燕；

【导师】 刘韩星； 罗大兵；

【作者基本信息】 武汉理工大学 ， 材料学， 2009， 硕士

【摘要】 复合介电储能材料是突出发挥聚合物高耐压和陶瓷高介电等优势,通过0-3复合方式而构成的多相材料,此类材料具有柔性好、密度低、分布均匀、成型容易、易于制成大面积薄片等优点,但是由于其介电性能太低从而影响了它的推广使用。本文针对复合介电材料的陶瓷相组元和聚合物组元介电差异调节原理,进行介电调节研究以便能够获得高耐压强度、高介电常数的复合介电储能材料,论文的主要研究工作包括:(1)通过建立Dilute模型,利用有限元法分析,对0-3型复合材料的结构和性能进行模拟计算,分析无机组元的颗粒尺寸、介电特性和相间介电平衡性等与复合材料耐压能力、整体介电性能之间的定性关系。(2)理论分析表明,降低陶瓷相介电常数或者提高聚合物基体介电常数是提高功能相内电势场分布的有效方法。针对聚合物介电常数较低问题,所以采用具有较高介电性的第三相来改善聚合物基体介电常数低的缺点,可以提高复合材料的介电性能。(3)开展陶瓷粉体BST聚合物基体PVDF-PAn的制备工艺,以及0-3型复合介电材料的合成方法探究,将共聚物PVDF-PAn以基体形式与陶瓷颗粒(BST)进行有机-无机复合,在一定温度、频率、电场下对材料进行介电性能表征,对不同方案下所得复合材料样品进行性能测试表明,PAn在纯基体PVDF中的分散度的提高、共聚物PVDF-PAn本身介电性能的提高、陶瓷颗粒形状、及良好的粒度分布都使得复合材料的介电常数和耐压强度。更多还原

【Abstract】 0-3 dielectric-composites comprise the high permitivitty of ceramic powder and high electric breakdown strength of polymers.They exhibit many advantatages,such as low brittleness,low density and even-distribution,easy to machine.But the low dielectricity of composites limits its application.This paper focuses on improving the properties of organic-inorganic energy storage media with the basis of the dielectric balance theories by adjusting the difference between the ceramics and polymers, composites with high electrical strength,moderate permitivitty are fabricated.The thesis consists of the following parts:(1) Dilute model was set up to analyse the properties of composites.According to Finite Element Analysis,some affecting factors,such as permittivity,adjustion of the difference of ceramic powder and polymers were studied.The permittivity of the components affects the distribution of electric field directly.In composites,the components of low permittivity could produce high electric field.(2) the researches showed,reducing the permittivity of ceramic or improving that of polymer matrix could enhance electric field.As to the low permittivity of polymers,the third dopant was added to improve its poor permittivity.Finally,the composites with high electric strength and moderate permittivity were obtained.(3) Systhesis of BST ceramic powder、emulsion fabrication of co-polymer PVDF-PAn and process of forming 0-3-composites were settled.Poly-aniline was prepared and added into PVDF by chemical ways so as to keep the high distribution for co-polymers.Ceramic powders were added in to co-polymers and formed the dielectric composites by thermal-forming method.At last the composites were measured at a certain temperature and electric field for its dielectric properties.The test data showed that the permittivity and electrical strength of composites were enhanced by improving the permittivity of the co-polymers at a large scale.更多还原