| 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.
|
PDF Full Text Request