Rectification Extrusion Of Heterogeneous Slurry And Its Application In The Preparation Of Silicone Rubber-based Thermal Conductive Pad

In recent years,with the development of electronic components in the direction of miniaturization,integration and high-power,their functions and performances are constantly improved,while power consumption and calorific value also continue to increase.The reliability of electronic components decreases by 10%when the temperature of electronic components rises by 2℃.It can be seen that heat dissipation has become an important bottleneck restricting the rapid development of electronic technology.In order to effectively solve the problem of heat dissipation,both academia and industry have devoted a lot of energy to research.At present,it has gradually developed into a new discipline-Thermal Management,which involves heat dissipation equipment,heat dissipation methods,heat dissipation materials and so on.Nowadays,the mainstream way of heat dissipation of electronic components is fan heat dissipation,that is,installing additional fans on high-power electronic components,while the rigid contact between electronic components and fans is not a perfect fit plane,there are a lot of air gap,low thermal conductivity air makes the cooling effect of fans worse,so the thermal interface materials used to fill the gap between the two come into being.Thermal interface materials have a market share of billions.The preparation methods of high thermal conductivity pads were studied from both micro and macro aspects.In micro aspect,the interfacial modification of heterogeneous slurry by coupling agent was studied.The slurry viscosity was reduced,the filling content of powder was increased,and the connection between powder and matrix was enhanced.It was found that the viscosity could be reduced by 43%at most when the use rate of n-Decyltrimethoxysilane was 2.5%.In addition,the pretreatment method was used.The thermal conductivity of heat conductive pad can be increased by 14.1%.Macroscopically,the influence of carbon nanotubes as thermal conductive powders on thermal conductive pads and the directional alignment effect of heterogeneous slurries composed of anisotropic thermal conductive powders and liquid polymer matrix during rectification extrusion were studied.The specific technological conditions for preparing high thermal conductive pads were also explored.It was found that when the length of carbon nanotubes was 10μm,the diameter was 30-80nm,and the mass fraction was 5%,the carbon nanotubes were extracted.The longitudinal thermal conductivity of the heat conducting pad prepared by rectifying extrusion process is 1.53 W?m^-1K^-1,which is 2.15 times of the transverse thermal conductivity.The thermal conductivity of the heat conducting pad can be further improved by modifying carbon nanotubes with coupling agent,reaching 2.03W?m^-1K^-1.