Application of silica nano material in polyester-imide enameled wire insulating varnish

Abstract

The invention relates to an application of a silica nano material in polyester-imide enameled wire insulating varnish. The method for dispersing nano-silica in polyester-imide varnish comprises the following steps in sequence: predispersing 6-8 parts of nano-silica and 0.6 parts of gamma-aminopropyl triethoxysilane (KH550) in 40 parts of modified polyester varnish, feeding silica into the above pre-dispersion A for not less than three times at intervals of 20-40 min so as to generate a pre-dispersion A; adding 50 parts of polyester-imide enameled wire insulating varnish and 10 parts of modified polyester enameled wire insulating varnish into the pre-dispersion A, dispersing for 1 hour to generate a pre-dispersion B; performing circulating continuous dispersion of the pre-dispersion B in a rod-pin dispenser for 3 hours, wherein the temperature of a dispersing cavity is controlled to be not more than 70 DEG C. Enameled wires prepared by the method of the invention have corona resistance which is up to above 100 times of that of common enameled wires; the prepared enameled wires have smooth surfaces without bright spots; the storage life of the insulating varnish is up to 1 year; the process has wide redundancy, and is convenient for the realization of robust process production.

Description

technical field [0001] The invention discloses a silicon dioxide nanometer material used in polyesterimide enameled wire insulating varnish, and relates to a dispersion technology in which silicon dioxide nanometer material is dispersed in polyesterimide enameled wire insulating varnish. Background technique [0002] When IGBT frequency conversion stepless speed regulation, a towering sharp wave rising instantaneously will be generated in the electromagnetic coil, and corona will be generated on the electromagnetic wire, and the insulation structure of the electromagnetic wire will be electrically aged under the action of the corona, causing the insulation structure to be damaged prematurely. . The solution is generally to add materials such as nano-silica, nano-titanium dioxide, and nano-alumina to the insulating paint. The dispersion of nano-materials in the paint is the key core technology. At present, paint manufacturers at home and abroad generally use the disc dispers...

AI Technical Summary

Problems solved by technology

This is very effective for nano-materials such as titanium dioxide and aluminum oxide. Since silica nano-materials are easy to agglomerate, it is difficult to disperse silica to insulating varnishes with an average particle size of less than 100 nanometers by the above method, resulting in the enameled wire during use. Matte surface with bright spots

It is also reported abroad that the sol-gel method is used to prepare silica nano-polyesterimide enameled wire insulating varnish, but the process is complicated, domestic enterprises have not mastered the key technology, and the insulating varnish made is easy to gel during storage and cannot be used.

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