A kind of heat-conducting aramid fiber nano insulating paper and preparation method thereof

Abstract

The invention discloses heat conduction type aramid nano insulation paper and a preparation method thereof. According to the heat conduction type aramid nano insulation paper and the preparation method thereof, disclosed by the invention, aramid nano fiber with high strength, high modulus, high length-diameter ratio, good temperature resistance and good insulativity is utilized as a matrix, and good mechanical performance, good insulativity, good temperature resistance and good flexibility are given to aramid nano insulation paper; hydroxylated nano boron nitride is used as heat conduction filler and is dispersed in the aramid nano fiber matrix so as to be used for a main carrier for heat conduction, so that interface bonding is optimized, interface thermal resistance is reduced, high heatconductivity is given to the aramid nano insulation paper, and meanwhile, the insulavitity of the aramid nano insulation paper cannot be influenced; the problems that since the heat conductivity of aramid insulation paper at present is low, electrical insulation equipment is poor in heat dissipation and short in service life are solved; meanwhile, the problems that since a heat conduction composite resin impregnation technology is utilized, insulation paper is hard and crispy, the technology is complicated and the like are avoided.

Description

technical field [0001] The invention belongs to the field of polymer nanomaterials and papermaking, and in particular relates to a thermally conductive aramid fiber nano insulating paper and a preparation method thereof. Background technique [0002] In the field of electrical insulation products such as motors and transformers, insulating paper made of aramid fibers has obvious advantages in thermal stability, electrical properties and mechanical properties compared with natural fiber (such as cellulose-based insulating paper) products, and can be Significantly improve the service life and safety of electrical appliances. Aramid insulating paper has excellent mechanical properties, insulation properties, good high temperature resistance and chemical stability. Aramid insulating paper is widely used in the form of paper, cardboard, paper-film composite materials, aramid mica paper, etc. for coil windings of motors and transformers with insulation grades above H (maximum ope...

AI Technical Summary

Problems solved by technology

However, there are several problems in this method: (1) hexagonal boron nitride is directly added to the slurry formed by mixing aramid chopped / pulp fiber, and the retention rate of boron nitride is very low, which affects its thermal conductivity; (2) The surface of aramid chopped fiber is smooth and has few active groups. Add micron-sized boron nitride directly to the slurry. There is no effective combination between boron nitride and aramid fiber. It is only physical deposition, which affects its strength. and thermal conductivity; (3) This traditional aramid insulating paper prepared by using chopped and pulp fibers still needs high temperature and high pressure hot pressing to ensure its strength, complex process and large equipment investment; (4) using silane coupling agent Aramid paper is impregnated with a composite resin solution composed of resin, which is not only complicated in process, but also makes the prepared aramid insulating paper become a prepreg after being impregnated with a thermally conductive resin adhesive. Although the insulating aramid prepreg has certain thermal conductivity, But it will cause it to become stiff and brittle, and lose the flexibility of aramid paper, which limits its application field

Therefore, there is no related technology of aramid insulating paper with high strength, high thermal conductivity, excellent flexibility, simple preparation process, and no need for hot pressing in the currently published patents.

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