Composite phase-change material and preparation method thereof

Abstract

The invention discloses a composite phase-changing material and making method, which comprises the following steps: 1) blending carbowax with molecular weight at 2000-10000 and anhydrous alcohol with weight rate at 0. 21-0. 34; heating to stir; forming the composite liquid; 2) dripping p-ethyl-siliconic acid with weight rate at 0. 61-0. 87 corresponding to carbowax at 0. 61-0. 87 into the composite solution in the step 1); stirring; adding water with molar weight at 2:1-6:1 corresponding to p-ethyl-siliconic acid; adjusting pH value of solution at 0. 5-2; stirring under normal temperature; 3) aging the sol in the step 2) for 24h under 40 deg. c; forming the gel; drying under high temperature to obtain the carbowax / silica composite phase-changing material. The invention stablizes the shape and good heat stability, which forms even composite phase-changing material.

Description

technical field [0001] The invention relates to material technology, in particular to composite phase-change materials. Background technique [0002] With the development of advanced infrared detection and guidance technology, various military targets on the future battlefield are facing severe threats. Infrared stealth technology, as an effective means to improve the survivability and defense penetration capability of weapon systems, has been highly concerned by countries all over the world. Phase change materials can absorb or release energy during the phase change process, forming an isothermal or nearly isothermal process to achieve the purpose of temperature control, so they are widely used in industry, agriculture, military, aviation, civil and other fields. [0003] Phase change materials (phase change materials PCM for short) used for temperature control mainly include inorganic phase change materials and organic phase change materials. Although inorganic phase cha...

AI Technical Summary

Problems solved by technology

Although inorganic phase change materials have the advantages of large phase change latent heat, high energy storage density, high thermal conductivity, and low price, there are corrosion, supercooling and phase separation phenomena; organic phase change materials have better formability in solid state Generally, supercooling and phase separation are not easy to occur, the material is less corrosive, and the performance is relatively stable, but there are disadvantages such as low thermal conductivity, low energy storage density, easy volatilization, oxidation and even combustion.

And most of the organic and inorganic phase change materials are solid-liquid phase change materials, the volume changes greatly during the phase transition, and there is a liquid state, so there must be a container to hold it, which causes inconvenience in actual use