Micro nanocomposite material with high thermal conductivity and preparation method thereof

Abstract

The invention discloses a micro nanocomposite material with high thermal conductivity and a preparation method thereof. The preparation method comprises the following steps: dispersing graphite or expanded graphite into a surface modifier solution, stirring at a high speed for 30-60 minutes, then performing ultrasounic stripping on the obtained mixture for 0.5-10 hours, filtering and drying to obtain micro nano structure thermal conducting filler; mixing the micro nano structure thermal conducting filler with a thermal plasticity polymer by virtue of fusion or solution, so as to obtain a micro nanocomposite material, then placing the obtained micro nanocomposite material into a mould, and performing hot press molding at the temperature of 170-300 DEG C and the pressure of 10-18MPa, so that the micro nanocomposite material with high thermal conductivity is obtained, wherein quality content of the micro nanocomposite material in a composite material is 5-30%. The micro nanocomposite material with high thermal conductivity is prepared through ultrasonic stripping under action of surfactant while graphite or expanded graphite is taken as a raw material. The micro nancomposite material with high thermal conductivity has excellent thermal conductivity and good mechanical property and is simple to prepare and low in cost.

Description

technical field [0001] The invention relates to a thermally conductive composite material, in particular to a high thermally conductive micro-nano composite material with excellent thermal conductivity and a preparation method thereof. Background technique [0002] As a widely used material, polymer has the advantages of corrosion resistance, light weight, low price, easy processing and molding, and its mechanical properties can be compared with metal materials, so it can replace metal in chemical industry, energy, and heat dissipation of electronic devices. , electronic information, electrical engineering, aerospace and other fields have potential application prospects. However, the poor thermal conductivity of polymers cannot meet the high thermal conductivity requirements in practical engineering. Therefore, the development of composite materials with excellent thermal conductivity is the key to the large-scale application of polymers. [0003] It is an effective way to...

AI Technical Summary

Problems solved by technology

The main problems of composite thermally conductive materials filled with micron-scale thermally conductive fillers: (1) In the case of low filling amount of thermally conductive fillers, the thermal conductivity of the composite material is not high; (2) In the case of high filling amount (greater than 30%), although The thermal conductivity has been significantly improved, but the comprehensive mechanical properties of the material have dropped sharply and significantly, which cannot meet the requirements of engineering use at all.

In contrast, composites modified by nanoscale carbon nanotubes, graphene or nano-graphite flakes have good thermal conductivity and mechanical properties, but these nano-thermal conductive fillers are easy to agglomerate in the polymer matrix, resulting in composite materials The improvement of thermal conductivity is limited, and the preparation yield of nanofillers is low, making it difficult for industrial production

In short, the existing composite heat-conducting materials cannot achieve high thermal conductivity and good comprehensive mechanical properties at the same time, and it is difficult to meet the actual needs of performance, thus limiting the wide application of heat-conducting composite materials