High thermal conduction and insulating two-component epoxy pouring sealant and use method thereof

Abstract

The invention discloses a two-component epoxy pouring sealant and a use method thereof. The two-component epoxy pouring sealant comprises a component A and a component B, wherein the component A comprises a modified epoxy resin, a diluent and a thermal conduction filler, the component B comprises a curing agent and a curing accelerant, the raw materials of the modified epoxy resin comprise an epoxy resin matrix, a vinyl monomer containing an ester group and a hydrophobic hexagonal boron nitride nano-sheet containing vinyl, the modified epoxy resin is produced by polymerizing the epoxy resin matrix and the remaining raw materials, and the boron nitride nano-sheet is prepared by using the following specific method: carrying out surface hydroxyl modification, carrying out freeze-thaw expansion treatment, and catalyzing boron nitride stripping and esterification modification by combining with a specific compound one-pot method. The use method comprises: mixing the component A and the component B, carrying out vacuum deaeration multiple times after the uniform mixing, and solidifying in stages at different temperatures. According to the present invention, the two-component epoxy pouringsealant can integrate performances of low viscosity, good flow permeability, high thermal conductivity coefficient, low linear expansion coefficient, high heat resistance and the like on the basis ofexcellent electrical and mechanical properties.

Description

technical field [0001] The invention belongs to the technical field of polymer composite materials and electrical engineering, and in particular relates to a high thermal conductivity and insulating epoxy potting glue and its application method. Background technique [0002] Epoxy resin is a kind of organic polymer compound containing 2 or more epoxy groups in a molecule, which has the characteristics of excellent electrical insulation, chemical corrosion resistance, strong adhesion, flexible and diverse formula design, and No small molecular by-products are produced during the curing process, the cured product has good dimensional stability, low equipment requirements, and good manufacturability. The high-performance epoxy potting adhesive prepared by epoxy resin can effectively strengthen the integrity of electronic components and improve the protection against foreign substances. Shock and vibration resistance, maintain the insulation performance of electronic components,...

AI Technical Summary

Problems solved by technology

However, with the development of modern science and technology, various special motors for specific purposes have emerged as the times require, especially larger-sized motors. The coupling method realizes the servo control of the synchronous motor. This kind of motor needs to run for a long time under the condition of frequent and rapid start in both forward and reverse directions. The stator and rotor of the motor must rotate, and the windings are completely immersed in the clutch oil (AFT oil). , the operating conditions of the motor are relatively harsh, so the reliability requirements are relatively high; at the same time, for such a large-sized motor winding, due to the shrinkage of the potting compound during the curing process, the dimensional change of the potting compound is related to the iron of the motor as the temperature changes. There is a certain difference in the dimensional changes of the core and the winding. The larger the workpiece size, the larger the absolute value of this difference, resulting in more serious cracking.

For example, the potting adhesives produced by some domestic manufacturers, including some products produced by imported technology, mostly have cracking problems, and some potting adhesives have cracked even before curing; although the high thermal conductivity epoxy potting adhesives produced by some foreign companies Good anti-crack performance, but the viscosity of the material is as high as 4000mPa s (65°C), the resin fluidity is very poor, and the service life is less than 0.5h. For larger motors, there is not enough time to complete vacuum defoaming and Vacuum potting and other operations lead to a large number of air bubbles and air gaps remaining inside the workpiece, and the quality and reliability of potting cannot be guaranteed

[0004] At the same time, the thermal conductivity of potting adhesives is still insufficient. For example, the Chinese invention patent CN103773298B discloses a high-thermal-conductivity insulating adhesive for high-power LED lamps and a preparation method thereof. The rate is still low, and the thermal conductivity does not exceed 6.6W (m / k)

Another example is the Chinese invention patent CN103087665B, which discloses a high-thermal-conductivity insulating low-viscosity epoxy resin potting compound and its preparation method. It is about 2.0W (m / k), and at the same time it is added as high as 10-13 times the amount of epoxy resin, the cost is high, and it is not conducive to the physical and mechanical properties and processability of the encapsulant

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