Study On Preparation And Properties Of Polymer Filled With BaTiO₃/PaNi Composites

Dielectric material has good application in high energy storage capacitors, missedcapacitors and microwave materials. Therefore, it has been the extensive attention ofresearchers. Especially in the energy storage capacitor materials it has a good prospect ofapplication. Cause of the dielectric material is a dielectric polarization. different materialshave different ways and degrees of the polarization. So a series of studies of the dielectricmaterial was carried out.In the present study, The single-phase ceramic material is one of the main researchfocus: such as BaTiO₃，Calcium copper titanate and so on. The single-phase ceramicmaterials have a high dielectric constant and the lower dielectric loss. But the ceramicmaterials need high-temperature sintering. Its preparation method is more complex;Two-phase composite material Include ceramic/polymer composites and conductor/polymer composites. Most often researchers studied conductor are metal conductor, thecarbon conductor and Conductive polymers conductor; Three-phase composite: Undernormal circumstances, the synthesis method is a simple doping three-phase composite.The three-phase composite material comprises a ceramic material, a conductive material,the polymer matrix material.The experiment preparation and study of two two-phase composite materials:BaTiO₃/polymer composites and PANI/polymer composites. A three-phase compositewas found, It uses the core-shell structure as a filler particles: BaTiO₃-PANI/polymercomposites. These materials were subjected to characterization and dielectric propertiestest. How to get good dielectric properties of composite materials, these materials are ofhigh dielectric constant and low dielectric loss.（1） BaTiO₃/polymer composites: The BaTiO₃Synthesis method is a sol-gel method.The final product is a BaTiO₃particle. BaTiO₃ceramic crystal form is tetragonal. BaTiO₃is well mixed with the polymer. The mixture was molded in a glass casting method. Thefollowing conclusions by testing its dielectric properties: Composite dielectric constant ofBaTiO₃content showed a trend first increases and then decreases. When the mass fraction of the BaTiO₃is reached60%, the dielectric constant is a maximum. With the increase inthe mass fraction of the BaTiO₃, the dielectric loss has been increased. After reaching60%, the rate of increase becomes faster. However, the dielectric constant of thiscomposite material is not too high. The application of this material is restricted in termsof high-energy storage material.（2） PANI/polymer composites: Conductive PANI prepared by emulsionpolymerization, describe the conductive PANI. The conductive PANI is well mixed withthe polymer. The mixture was molded in a glass casting method. The followingconclusions by testing its dielectric properties: With the increase of the conductive PANIof the conductor material, the dielectric constant of the composite material is graduallyincreased, the corresponding increase in dielectric loss, The PANI the volume fractionreaches a certain amount, i.e. near the percolation threshold. The dielectric constant anddielectric loss were mutated. The experimental results show that the percolation thresholdof the composites is0.13, but this material has certain shortcomings, its dielectric lossesare higher.（3） BaTiO₃-PANI/polymer composites: This experimental introduction of thecore-shell particles of PANI-coated BaTiO₃. This experiment makes use of emulsionpolymerization to generate conductive PANI in the surface of the particles of BaTiO₃anddescribes the composites. This core-shell particle is well mixed with the polymer.BaTiO₃-PANI/polymer composites are generated. The composite material is to test theperformance of the dielectric. Experimental conclusion is that dielectric properties of thiscomposite material are better, as compared with the previous two two-phase compositematerials. It has a high dielectric constant and low dielectric loss, it is a good energystorage material, and it has a good prospect of application.