Nano-tin-loaded polyimide high-dielectric-permittivity composite film doped with nano lithium titanate and used for capacitor and preparing method of composite film

Abstract

The invention discloses a nano-tin-loaded polyimide high-dielectric-permittivity composite film doped with nano lithium titanate and used for a capacitor. According to the composite film, the nano lithium titanate, nano tin and other filler are doped in the polyimide film preparing process, and nano tin powder is loaded in the nano lithium titanate to improve the dispersity and the utilization efficiency of the nano lithium titanate. A powder body is covered with a polyvinyl alcohol film good in stability in an organic solvent, and the composite powder body with the surface modified and processed by a silane coupling agent is good in compatibility with an organic glue solution interface and can be evenly dispersed more easily, so that dielectric properties of a material are efficiently and stably improved, and dielectric loss is reduced. Cellulose acetate is added to improve use performance of the film and elasticity is better. The dielectric properties of the finally prepared polyimide film pure in composite film material are greatly improved, good mechanical properties and processability are still maintained, and application prospects are good.

Description

technical field [0001] The invention relates to the technical field of preparation of high-dielectric composite materials, in particular to a polyimide high-dielectric composite film for capacitors, which is mixed with nano-lithium titanate and loaded with nano-tin, and a preparation method thereof. Background technique [0002] With the advancement of electronic technology, the requirements for the dielectric properties and energy storage capacity of capacitors are getting higher and higher. It is particularly important to develop dielectric materials with high dielectric constant and low dielectric loss. Traditional film capacitor dielectric materials are mainly There are non-polar polystyrene, polyethylene, polypropylene and polar polyimide, polycarbonate and other materials, among which polyimide has good mechanical properties and thermal stability, easy processability, and base It has the advantages of good material compatibility and easy film formation, and is outstand...

AI Technical Summary

Problems solved by technology

The dielectric constant of pure polyimide film is too low to meet the production requirements. At present, the common method for improving the dielectric constant of the film is mainly to use the method of mixing high dielectric materials in the polymer. However, these methods are generally Defects are manifested in the deterioration of film processing performance, the increase of dielectric constant and the increase of dielectric loss, etc.