Preparation And Properties Of Polymer Blend Composite Dielectric Film

In order to explore how to prepare dielectric energy storage materials with low loss,high breakdown field strength,and high energy storage,this paper applies a rubber particle:Methyl methacrylate-butadiene-styrene(MBS)is added to Poly(vinylidene fluoride)(PVDF),and PVDF/MBS composite film is prepared by solution casting method.The study found that MBS has good dispersion and compatibility in the PVDF.The entangled state between MBS and PVDF can reduce the gap in the matrix,which is beneficial to improve the breakdown field strength of the composite film and increase the energy storage density.It was also found that when 12vol%MBS was added,the maximum breakdown strength of PVDF/MBS composite film was 391.05 k V/mm,and the effective energy storage density was 6.39J/cm~3,which were 23.7%and 49.0%higher than pure PVDF film,respectively.Using different heat treatment methods,the PVDF+12vol%MBS composite film was reprocessed,and the effects on the dielectric energy storage performance of the composite film were explored separately.Through experiments,it was found that the combined heat treatment of hot pressing,quenching and annealing on the sample film can effectively increase its dielectric constant and breakdown field strength,and reduce losses and residual polarization.Compared with single heat treatment,it can get better energy storage performance.After composite heat treatment,the maximum breakdown field strength of PVDF+12vol%MBS composite film is 503.79 k V/mm,and the effective energy storage density is 8.69 J/cm~3.Finally,a new type of preparation process——"non-equilibrium method"is introduced,which includes improved electrospinning and composite heat treatment technology,which can more uniformly disperse the filler in the composite film and has excellent control,it is an effective method to prepare dielectric composite energy storage thin film materials.The PVDF+12vol%MBS composite film prepared by this method has a maximum breakdown field strength of 523.18 k V/mm and an effective energy storage density of 9.78 J/cm~3.Compared with the performance of the sample with the same composition prepared by the balance method,it has a certain degree of improvement.