240results about How to "High latent heat of phase change" patented technology

The invention relates to a preparation method of the phase change material, in particular to a preparation method of the compound phase change material which has a higher latent heat of phase change and a high thermal conductivity under the solid and the liquid states. The preparation steps are as follows: firstly, metal nanowires are prepared; secondly, the metal nanowires are dispersed into an organic solvent; thirdly, an organic phase change material and the mixture are mixed; fourthly, the mixture is dispersed by ultrasonic under the condition of heating, and the organic solvent is removed. The phase change material prepared by the method has the advantages that the art is simple, the cost is low, and the thermal conductivity of the organic phase change material is enhanced greatly while the latent heat of phase change is maintained, thus the performance of the organic phase change material is improved effectively, and the application scope is greatly developed.

The invention provides a molten nano-carbonate heat transfer and accumulation medium, and a preparation method and an application thereof, and belongs to the technical field of heat storage and transmission. The molten nano-carbonate heat transfer and accumulation medium contains a molten carbonate system formed by potassium carbonate, sodium carbonate, lithium carbonate and sodium chloride, nanoparticles are added into the molten carbonate system, and the nanoparticles are metal oxide and/or nonmetal oxide; and the nanoparticles are dispersed into the molten carbonate system, and the molten nano-carbonate heat transfer and accumulation medium is formed through compounding. The melting point of molten nano-carbonate is low, so the molten nano-carbonate heat transfer and accumulation medium has an upper limit use temperature of 800DEG C, has a good heat stability and a high heat conductivity, and is very suitable for the heat accumulation and transfer systems of industrial energy accumulation and solar photo-thermal power generation.

The invention discloses a phase change energy storage microcapsule of composite shell and its making method, wherein the core material of the microcapsule employs tetradecane, pentadecane or hexadecane, the shell layer has a composite construction, the inner layer is melamine resin, the outer layer is PEG200 modified melamine resin, or PEG200 modified melamine, or copolycondensation resin of methyl poultry manure amine, acetyl poultry manure amine or benzene substituted melamine.

The invention discloses a graphitized graded porous carbon composite phase change energy storage material and a preparation method thereof. A carbon precursor with a low price, a graphitization catalyst and a pore-forming agent are used as raw materials and are treated through technologies including ball milling and mixing, carbonization and the like to prepare graphitized graded porous carbon; then the prepared graphitized graded porous carbon is used as a supporting material and is compounded with a phase change material to obtain the graphitized graded porous carbon composite phase change energy storage material. The porous carbon material prepared by the invention has a three-dimensional intercommunication graded porous network structure and a high graphitization degree; the sizing andpackaging of the phase change material are easy to realize; meanwhile, a good heat-conducting network channel can be provided and the heat transferring performance is enhanced; the porous carbon material is prepared by adopting an additive containing metal salt; in a preparation process, part of metal substances can be reduced by utilizing carbothermal reduction reaction and the heat conduction performance of the material is further increased, so that the composite phase change energy storage material with high heat conduction performance and good chemical stability is obtained.

An efficient heat-accumulated hydrogen accumulator for Mg-base hydrogen-bearing material is a cylindrical body, which is composed of external and internal shells and vacuum layer between them, insulating layer on the inner surface of internal shell, heat accumulating tubes in the insulating layer, heat transfer tube at inside of the most external heat accumulating layer, hydrogen distributing and filtering tube passing through hdyrogen filter layer and installed at central position of internal shell, and hydrogen filter layer installed on supporting plate on the internal shell. It features that the heat generated by absorbing hydrogen is accumulated for supplying it when hydrogen is released.

The invention discloses a cigarette tow with a phase change heat absorption function. The tow is obtained as follows: microcapsules containing a phase change agent are added to a food fiber-grade polylactic acid material in a melt spinning process, and drying, melting, spinning, cooling, oiling, drafting, crimping and drying setting processes are performed. During smoking of a cigarette with a filter tip processed from fiber prepared with the preparation method, polylactic aid hollow fiber has high adsorption/absorption capacity for polar and non-polar smoke component gases; meanwhile, the temperature of smoke passing through the filter tip is increased, the polylactic acid material and the phase change material in the microcapsules absorb heat during phase state conversion, the smoke temperature is decreased, a harm reduction effect is realized, the prepared cigarette with the polylactic acid filter tip has unique smell absorption style, and harmful substances in smoke can be effectively filtered out.

The invention discloses a boron nitride/graphene double-heat-conduction-base aerogel composite phase change material. The material is formed by compounding modified boron nitride/graphene aerogel andn-octadecane by adopting a vacuum impregnation method. The double-heat-conduction aerogel is prepared by taking graphene oxide, modified boron nitride, polyvinylpyrrolidone and ethylenediamine as rawmaterials to prepare boron nitride/graphene hydrogel, freeze-drying the boron nitride/graphene hydrogel and then calcining the boron nitride/graphene hydrogel at a constant temperature. Polyvinylpyrrolidone is used as a cross-linking agent, and ethylenediamine is used as a reducing agent. A preparation method of the composite phase change material comprises the following steps: 1) preparing modified boron nitride; 2) preparing boron nitride/graphene double-heat-conduction-base aerogel; and 3) preparing the boron nitride/graphene double-heat-conduction-base aerogel composite phase change material. When the material is applied as a phase change material, the heat conductivity coefficient is 0.9-1.6 W/(m.K); wherein the phase change temperature is 19-32 DEG C, and the phase change latent heatis 200-220 J/g. The composite phase change material has the following advantages: 1, the heat conductivity coefficient is improved by 738%; 2, the leakage problem in the phase change process is effectively solved; and 3, the phase-change latent heat and the heat stability are high;

The invention discloses a composite phase-change energy-storage material and a preparation method thereof and aims to provide a composite phase-change energy-storage material with high phase-change latent heat, leakage resistance, good heat-conducting performance and low cost and a preparation method thereof. The invention adopts the technical scheme that the composite phase-change energy-storage material comprises a stearic acid phase-change material and nerchinskite as a material combined with the stearic acid phase-change material. The preparation method comprises the following steps of: (1) drying the nerchinskite in vacuum at 150-250 DEG C for 1-3h and cooling to a room temperature; (2) adding an ethanol solution of sulphuric acid to the nerchinskite, stirring at 30-50 DEG C for 3-5h, filtering, washing with the ethanol solution to be neutral and carrying out suction filtration; (3) drying at 70-90 DEG C and grinding to prepare a stearic acid phase-change material carrier; (4) preparing an ethanol solution of the stearic acid; and (5) putting the ethanol solution of the stearic acid into the dispersion liquid of the nerchinskite and the ethanol and drying at 80 DEG C to have constant weight so as to obtain a stearic acid/nerchinskite composite phase-change energy-storage material. The invention is used for heat-storage materials.

The invention relates to a preparation method of a composite phase-change material, belonging to the technical field of application of a new material. In the method, nano SiO2 powder having high adsorption property and nano TiO2 powder having an infrared shielding effect are used as substrates to adsorb paraffin so as to prepare a composite phase-change energy storage material. The preparation method comprises the following steps: A. placing a phase-change material in a beaker, heating the beaker in a thermostatic water bath, adding distilled water and emulsifying agent to the phase-change material, and carrying out high-speed shearing and emulsification with a high-shear emulsifying machine; B. uniformly mixing nano SiO2 and nano TiO2, and then, heating the mixture in a beaker; and C. pouring the phase-change material obtained after emulsification in the step A into the oxide powder in the step B, uniformly mixing, drying in an oven to obtain lumpish solids, and grinding the lumpish solids into powder. The invention has the advantages of simple process and low cost, can effectively solve the problem of leakage in the solid-liquid phase change process and can greatly improve the phase-change temperature, latent heat of phase change, thermal stability and heat storage effect of phase-change materials such as paraffin and the like.

The invention discloses a form-stable phase change material with a multilevel package structure. The form-stable phase change material is prepared from ingredients by mass percent: 38 to 70% of phasechange material, 5 to 20% of first-stage package porous graphite, 20 to 50% of second-stage package thermoplastic polymer. According to the form-stable phase change material, the phase change material, the porous graphite and the thermoplastic polymer are utilized as materials, the porous graphite is utilized to perform first-stage package on the phase change material, the thermoplastic polymer isutilized to perform second-stage package on the phase change material in a melting and blending process, and the form-stable phase change material can be prepared by twice package. The form-stable phase change material disclosed by the invention has the advantages of good heat conductivity coefficient, phase change latent heat and mechanical property.

The invention relates to a polyether-based composite phase change material and a preparation method thereof, and belongs to the technical field of novel materials. The polyether-based composite phasechange material comprises the following components in percent by mass: 23-70% of a phase change supporting material, 1-7% of a carbon material and 30-75% of polyethylene glycol, wherein the phase change supporting material is a polyacrylate polymer, and a monomer structure of the olyacrylate polymer is as shown in the specification, wherein n is 5-90, m is 50-1000, R1 is -H or -CH3, and R2 is -CH3or -CH2CH3; and the carbon material is graphene or graphene oxide. The novel heat storage material is high in energy storage density, high in heat conductivity coefficient, good in heat stability, simple in synthesis technology and good in shaping performance, so that the novel heat storage material has very strong practicability.

The invention discloses a method for manufacturing phase-change heat absorption swelling fire-retardant wood and the swelling fire-retardant wood. The manufacturing method includes the following steps that the wood is processed and manufactured according to the dimensions required, so that a solid wood component is obtained; the solid wood component is subjected to degreasing and duct dredging pretreatment, and accordingly the pretreated solid wood component can be obtained; the pretreated solid wood component is put into phase-change heat absorption swelling fire-retardant steeping liquor for conducting vacuum pressure impregnation treatment, and then drying is performed, so that the solid wood component filled with a phase-change heat absorption swelling fire-retardant material is obtained; the solid wood component filled with the phase-change heat absorption swelling fire-retardant material is subjected to sanding shaping and surface closing protective treatment, and accordingly the phase-change heat absorption swelling fire-retardant wood is obtained. The swelling fire-retardant wood obtained through the manufacturing method achieves phase-change heat absorption in the heating process of the wood and forms a swelling foam carbon layer under the fire condition, the change of fires can be lowered and fire losses are reduced.

The invention discloses an inorganic-salt efficient coolant for refrigerated products. The inorganic-salt efficient coolant is prepared from the following raw materials by mass percent: 20% to 35% of main energy storage agent, 5% to 10% of nucleating agent and 1% to 5% of thickener. The main energy storage agent is an inorganic-salt mixture of ammonium bromide (NH4Br) and a cooling agent, i.e., ammonium chloride (NH4Cl). The nucleating agent is one of strontium chloride (SrCl2), magnesium sulfate (MgSO4), sodium metaphosphate (Na2P2O7.10H2O) and potassium sulfate (K2SO4). The thickener is xanthan gum, and the xanthan gum, serving as the thickener, has a remarkable effect on the phase separation of inorganic-salt phase-change cold storage materials. The inorganic-salt phase-change coolant provided by the invention has the advantages that the latent heat of phase change is about 280KJ/kg, the degree of supercooling is low, and the cycle stability is good. The phase change temperature of the coolant is -18 DEG C to -22 DEG C, thereby meeting the requirements of frozen foods and frozen drugs on temperature.

The invention relates to a solid-solid phase change material and a preparation method thereof, and belongs to the field of phase change energy storage materials. The solid-solid phase change materialcomprises a component A and a component B, wherein the addition amount of the component A is 50-97% and the addition amount of the component B is 3-50% according to the percentage of the total mass ofthe raw materials, wherein the component A is a phase change material component, and comprises the following components in percentage by mass: 0-30% of an inorganic salt, 41-96.8% of water, 1-8% of fiber, 0.1-2% of a dispersant, 0.5-5% of a nucleating agent, 1-8% of a thickening agent and 0.5-6% of a heat conducting medium, wherein the component B is a curing component and comprises the followingcomponents in percentage by mass: 3-25% of isocyanate, 75-97% of hydrophilic polyether polyol and 20 ppm-200 ppm of A retarder accounting for the total mass of the component B. Compared with the existing water-based phase change material, the solid-solid phase change material provided by the invention not only furthest retains the characteristics of high phase change latent heat and low cost of the water-based phase change material, but also has no leakage risk and better heat conductivity.

The invention provides a preparation method of a carbonized wood-based composite phase-change energy storage material, which comprises the following steps: using a balsa woodblock from which part of lignin is removed as a matrix and SiO2 aerogel as a reinforcing phase to support a fiber matrix, and impregnating a phase-change material into the carbonized wood- SiO2 aerogel matrix by a vacuum impregnation method. According to the method, the pore channel structure of the balsa wood is reinforced by using the SiO2 aerogel, so that the volume shrinkage of the balsa wood fiber matrix in the carbonization process is reduced, and the original multi-stage pore structure of the wood is maintained; and the SiO2 aerogel further enhances the specific surface area of the packaging substrate material while reinforcing the pore structure of the carbonized wood, the SiO2 aerogel improves the accommodating capacity of the whole substrate to the phase-change material by means of the unique pore diameter and pore structure, and the packaging rate exceeds 90%. The problem of leakage of the phase-change energy storage material in use is solved, the heat storage and release efficiency of the packaged phase-change energy storage material is improved, and a new direction is developed for research of a frame matrix of the phase-change energy storage material.