Low-temperature phase-change composite material and preparation method thereof

Abstract

The invention provides a low-temperature phase-change composite material and a preparation method thereof, and belongs to the technical field of composite materials. The preparation method of the low-temperature phase-change composite material comprises the following steps: (1) modifying blast furnace slag by using acid liquor or alkali liquor to obtain modified blast furnace slag; (2) mixing paraffin, graphene oxide and a dispersing agent to obtain paraffin containing graphene oxide; and (3) mixing the modified blast furnace slag with the paraffin containing graphene oxide to obtain the low-temperature phase-change composite material. The result of the embodiment shows that the heat storage rate of the low-temperature phase-change composite material obtained by modifying the blast furnace slag with the acid liquor is 9.31 W/(m < 2 >. K), and the steady-state heat conductivity coefficient is 0.65 W/(m. K); the heat storage rate of the low-temperature phase-change composite material obtained by modifying the blast furnace slag with alkali liquor is 8.90 W/(m < 2 >. K), and the steady-state heat conductivity coefficient is 0.45 W/(m. K).

Description

technical field [0001] The invention relates to the technical field of composite materials, in particular to a low-temperature phase-change composite material and a preparation method thereof. Background technique [0002] Low-temperature phase-change materials absorb or release latent heat during the process of phase-change materials changing from solid to liquid or from liquid to solid at low temperature (<200°C), which can solve the contradiction between energy supply and demand in the distribution of time and space. Effectively improve energy utilization. As the most widely used organic phase change material, paraffin wax has the advantages of stable phase change temperature, non-toxicity, high latent heat, non-corrosion, no supercooling phenomenon during solidification, and low price, but its thermal conductivity is low and its heat storage capacity per unit volume is low. Weakness and low density limit the energy storage capacity of phase change composite materials...

AI Technical Summary

Problems solved by technology

As the most widely used organic phase change material, paraffin wax has the advantages of stable phase change temperature, non-toxicity, high latent heat, non-corrosion, no supercooling phenomenon during solidification, and low price, but its thermal conductivity is low and its heat storage capacity per unit volume is low. Weakness and low density limit the energy storage capacity of phase change composite materials during the low temperature phase change process. Adding high thermal conductivity materials to the paraffin wax reduces the overall thermal resistance of the composite material during the phase change process, that is, increases the thermal conductivity of the material. Enhancing the Thermal Conductivity of Composite Phase Change Materials

[0003] The currently published invention patent CN111100606A: A low-temperature composite phase-change energy storage material and its preparation method and application discloses that the phase-change energy storage microcapsule uses an organic phase-change material as the core material, but the thermal conductivity of the organic phase-change material Low, which is not conducive to the heat storage and release capacity of the phase change process. In order to improve the thermal conductivity of the material and the carrier, graphene oxide is added. The amount of graphene oxide added is large and the cost is high

Wanqian and others studied the addition of high thermal conductivity skeleton aluminum foam to paraffin to improve the problem of low thermal conductivity of paraffin wax, but there is a problem of paraffin leakage, which affects the promotion and application of composite materials

Blast furnace slag has small porosity and limited porous structure to accommodate materials. Using blast furnace slag as a carrier of paraffin requires adding a large amount of blast furnace slag, which leads to a decrease in the relative amount of paraffin, which in turn reduces the heat storage rate of the composite material.

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