Heat-conducting silica gel as well as preparation method and application thereof

Abstract

The invention relates to the technical field of heat-conducting materials, and particularly discloses heat-conducting silica gel as well as a preparation method and application thereof. The heat-conducting silica gel comprises vinyl-containing organopolysiloxane, hydrogen-containing organopolysiloxane and a heat-conducting filler. The molar mass ratio of the hydrogen group in the hydrogen group-containing organopolysiloxane to the vinyl group in the vinyl group-containing organopolysiloxane is 1: (2-10). A long-chain alkyl group is introduced into the side group of the vinyl group-containing organopolysiloxane, and under the steric hindrance effect of the long-chain alkyl group, by adjusting the molar mass ratio of the hydrogen group in the hydrogen-group-containing organopolysiloxane to the vinyl group in the vinyl-containing organopolysiloxane in the system and treating the heat-conducting filler in advance, the prepared heat-conducting silica gel is in a semi-flowing paste state. The heat-conducting silica gel is convenient to construct, high in heat conductivity, low in permeability, good in heat resistance, low in viscosity, stable in performance, capable of being used for a long time and reused, and suitable for heat-dissipating parts of equipment such as electronic and electrical elements or power batteries.

Description

technical field [0001] The invention relates to the technical field of thermally conductive materials, in particular to the technical field of thermally conductive gels, and in particular to a thermally conductive silicone gel and a preparation method and application thereof. Background technique [0002] With the miniaturization and integration of electronic devices, the power of electronic devices continues to increase, and the heat generated by them increases. Therefore, effective thermal management is very urgent for electronic devices, and the main purpose of thermal management is to dissipate heat. Due to the roughness of the surface of electronic devices, when the two surfaces are joined together, only a small part of the surface area actually touches, while the rest of the area is separated by air, which has a thermal conductivity of only 0.026W / (m·K), the heat is difficult to transfer through the air at the interface. In this case a thermally conductive interface ...

AI Technical Summary

Problems solved by technology

At present, the thermal conductivity of thermally conductive gels on the market is generally below 3W / (m·K), which is difficult to meet the high thermal conductivity requirements of the current market; and these thermally conductive gels are limited by the formulation process, so their viscosity and oil leakage rate are low. Very high, difficult to maintain stable performance

In addition, some thermally conductive gels need to be cured at room temperature for a long time or under high temperature conditions during the construction process, so there are problems such as complex construction technology

[0004] In the prior art, in order to achieve high thermal conductivity (above 3W / (m·K)), a single-component thermally conductive gel usually needs to be filled with a large amount of thermally conductive filler in the formula, so there will be a single-component thermally conductive gel composition The viscosity is very high; in addition, the one-component thermally conductive silicone gel on the market generally achieves the effect of partial crosslinking by controlling the content of vinyl silicone oil and hydrogen-containing silicone oil in the system, but this method has some ethylene The base silicone oil or hydrogen-containing silicone oil molecules have not reacted, so oil leakage is prone to occur, and problems such as unstable performance are prone to occur

In addition, most of the one-component thermally conductive gel compositions on the market need to be stored at low temperature, otherwise they are prone to curing and cause failure, and they need to be cured for a long time or heated and cured during the construction process, which leads to the problem of complex construction process

Images