CN111303839A - Inorganic phase change material and preparation method thereof - Google Patents

Abstract

The present disclosure provides an inorganic phase change material, comprising: the phase-change material comprises, by mass, 45% -86.75% of water, 9.25% -51% of inorganic salt, 0.051% -1.1% of stabilizer, 0.5% -1% of corrosion inhibitor, 0.2% -1% of nucleating agent and 0.3% -2% of setting agent. According to the present disclosure, an inorganic phase change material having high latent heat of phase change and good cycle stability, and a method for preparing the same can be provided.

Description

Inorganic phase change material and preparation method thereof

technical field

The present disclosure particularly relates to an inorganic phase change material and a preparation method thereof.

Background technique

Cold-chain transportation refers to the transportation in which the transported goods are always kept at a specific temperature in the whole process of transportation, whether it is loading and unloading, changing the transportation mode, changing the packaging equipment, etc. In the traditional cold chain transportation, the cost of transportation and the effective working time of the cold box are the main concerns of the cold chain transportation industry. Currently, long-distance transport generally takes several days, especially in extreme environments, and some of the transported goods need to maintain a constant temperature for a long time. Among them, the cold chain transportation of food and medicine is particularly important. For example, medical items such as blood, vaccines, and medicines need to be stored at a specific temperature (eg -18°C to -23°C) for cold chain transportation.

At present, compositions containing aqueous sodium chloride solution are also used as coolants in cold chain transportation to maintain a constant temperature. However, such coolants often have shortcomings such as supercooling, phase separation and easy corrosion during use, resulting in poor circulation stability of the coolant, which makes it easy to deviate from the required constant temperature during cold chain transportation. The phenomenon.

SUMMARY OF THE INVENTION

The present disclosure has been made in view of the above-mentioned state of the art, and an object of the present disclosure is to provide an inorganic phase change material with high latent heat of phase change and good cycle stability.

To this end, one aspect of the present disclosure provides an inorganic phase change material, which includes: water, an inorganic salt, a stabilizer, a corrosion inhibitor, a nucleating agent, and a shaping agent, and the inorganic salt includes sodium chloride, potassium chloride and ammonium chloride, the stabilizer includes clinoptilolite and modified nano-copper wires, and the inorganic phase change material has a phase transition temperature, the phase transition temperature is -18°C to -23°C, and the inorganic phase change material has a phase transition temperature of -18°C to -23°C. In the phase change material, the mass percentage of water is 45% to 86.75%; the mass percentage of the inorganic salt is 9.25% to 51%, and in the inorganic salt, the mass percentage of the sodium chloride is 5% to 16% %, the mass percentage of the potassium chloride is 0.25% to 20%, the mass percentage of the ammonium chloride is 4% to 15%; the mass fraction of the stabilizer is 0.051% to 1.1%, and the stabilizer In the agent, the mass percentage of the clinoptilolite is 0.5% to 1%, the mass percentage of the modified nano copper wire is 0.01% to 0.1%; the mass percentage of the corrosion inhibitor is 0.5% to 1%; The mass percentage of the nucleating agent is 0.2% to 1%; the mass percentage of the styling agent is 0.3% to 2%. Thereby, the latent heat of phase transition can be increased, and the cycle stability can be improved.

In addition, in the inorganic phase change material involved in one aspect of the present disclosure, optionally, the corrosion inhibitor is at least one selected from the group consisting of nitrite, chromate, phosphate, silicate, and sodium benzoate The nucleating agent is at least one selected from sodium tetraborate, sodium silicate, sodium pyrophosphate, silicon dioxide and diatomaceous earth, and the styling agent is selected from sodium hydroxymethyl cellulose, carboxymethyl cellulose At least one of sodium methylcellulose, xanthan gum, and silica. Thereby, the degree of supercooling can be reduced, the phenomenon of phase separation occurring in the phase transformation process can be reduced, and the effect of preventing corrosion can be obtained.

In addition, in the inorganic phase change material involved in an aspect of the present disclosure, optionally, the clinoptilolite forms an ionic complex with the sodium chloride and the potassium chloride. Thereby, it can contribute to further improving the cycle stability.

In addition, in the inorganic phase change material according to an aspect of the present disclosure, optionally, the diameter of the modified copper nanowires is 14 nm to 30 nm, and the length of the modified copper nanowires is 20 μm to 30 μm, so The particle size of the clinoptilolite is 1 mm to 3 mm. In this way, the dispersibility of the modified copper nanowires can be improved, and the ion complex reaction between the clinoptilolite and the sodium chloride and the potassium chloride can be better performed.

In addition, in the inorganic phase change material involved in an aspect of the present disclosure, optionally, the inorganic phase change material is cooled to a temperature lower than the phase change temperature and used as a coolant. Thereby, it can be used for maintaining a constant temperature.

In addition, in the inorganic phase change material involved in an aspect of the present disclosure, optionally, in the inorganic phase change material, the potassium chloride and the ammonium chloride can form a hydrate. Thereby, the transformation temperature can be lowered, and the latent heat of transformation can be increased.

Another aspect of the present disclosure provides a method for preparing an inorganic phase change material, comprising: (a) water, an inorganic salt, a stabilizer, a corrosion inhibitor, a nucleating agent, and a shaping agent, the inorganic salt comprising a chloride Sodium, potassium chloride and ammonium chloride, the stabilizer includes clinoptilolite and modified nano-copper wire; (b) sodium chloride, potassium chloride and clinoptilolite are ground and added to water, mixed to form a first mixed solution; and (c) adding ammonium chloride, corrosion inhibitor, modified nano-copper wire, sizing agent and nucleating agent to the first mixed solution, and mixing to form a second mixed solution to obtain an inorganic phase change material , wherein the inorganic phase change material has a phase transition temperature, the phase transition temperature is -18°C to -23°C, and in the inorganic phase change material, the mass percentage of water is 45% to 86.75%; the The mass fraction of the inorganic salt is 9.25% to 51%, in the inorganic salt, the mass percentage of the sodium chloride is 5% to 16%, and the mass percentage of the potassium chloride is 0.25% to 20%, so The mass percentage of the ammonium chloride is 4% to 15%; the mass fraction of the stabilizer is 0.051% to 1.1%, and in the stabilizer, the mass percentage of the clinoptilolite is 0.5% to 1%, The mass percentage of the modified nano copper wire is 0.01% to 0.1%; the mass percentage of the corrosion inhibitor is 0.5% to 1%; the mass percentage of the nucleating agent is 0.2% to 1%; the shaping The mass percentage of the agent is 0.3% to 2%. In this case, the ionic complexation of clinoptilolite with sodium chloride and potassium chloride can be promoted by grinding, so that the cycle stability of the inorganic phase change material can be improved, so as to obtain high latent heat of phase change and cycle stability. Good inorganic phase change material.

In addition, in the preparation method of the inorganic phase change material involved in another aspect of the present disclosure, optionally, in step (c), the stirring treatment is maintained, and the second mixed solution is subjected to ultrasonic treatment to obtain the Inorganic phase change materials. Thus, the components in the prepared inorganic phase change material can be uniformly dispersed, thereby helping to improve the performance of the prepared inorganic phase change material.

In addition, in the preparation method of the inorganic phase change material involved in another aspect of the present disclosure, optionally, the corrosion inhibitor is selected from nitrite, chromate, phosphate, silicate, sodium benzoate At least one of, the nucleating agent is at least one selected from sodium tetraborate, sodium silicate, sodium pyrophosphate, silicon dioxide, diatomaceous earth, and the styling agent is selected from hydroxymethyl cellulose At least one of plain sodium, sodium carboxymethyl cellulose, xanthan gum, and white carbon black. In this way, the degree of supercooling of the inorganic phase change material can be reduced, the phenomenon of phase separation generated by the inorganic phase change material during the phase change process can be reduced, and the inorganic phase change material can be made to have the effect of anti-corrosion.

In addition, in the preparation method of the inorganic phase change material involved in another aspect of the present disclosure, optionally, in step (b), the sodium chloride and the potassium chloride are mixed before adding the The clinoptilolite is ground. Thereby, clinoptilolite can be ion-complexed with sodium chloride and potassium chloride ions more preferably.

According to the present disclosure, an inorganic phase change material with high latent heat of phase change and good cycle stability and a preparation method thereof can be provided.

Description of drawings

FIG. 1 is a schematic flowchart illustrating a method for preparing an inorganic phase change material according to an example of the present disclosure.

Detailed ways

Hereinafter, preferred embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. In the following description, the same reference numerals are assigned to the same components, and overlapping descriptions are omitted. In addition, the drawings are only schematic diagrams, and the ratios of the dimensions of the members, the shapes of the members, and the like may be different from the actual ones.

In some examples, the inorganic phase change material involved in the present disclosure can be used as a coolant, for example, for refrigerated transportation, biomedicine and blood sample cold chain transportation, etc., for example, it can be used as a coolant for maintaining the temperature at -18°C to -23°C .

In some examples, the inorganic phase change materials involved in the present disclosure can be used for refrigerated transportation, daily refrigerated use, etc., as a coolant for refrigerated transportation, and in some examples, can be used in refrigerated compartments, refrigerated ice packs, mobile cold storage, etc., For daily refrigeration use, in some examples, it can be used in refrigerators, vehicle-mounted incubators, and the like.

In some examples, when using the inorganic phase change material of the present disclosure, it can be packaged in a sealed package and used as a coolant. Such a cooling bag can be placed around items (high-end foods, medicines, etc.) that need to be kept warm in an incubator, for example, to perform heat preservation work. In addition, the inorganic phase change material involved in the present disclosure may be a colloidal liquid, and in this case, the sealed package containing the inorganic phase change material may be changeable in shape.

In this embodiment, the inorganic phase change material may include: water, inorganic salts, stabilizers, corrosion inhibitors, nucleating agents, and styling agents. Wherein, the inorganic salt can include sodium chloride, potassium chloride and ammonium chloride, and the stabilizer can include clinoptilolite and modified nano copper wire. In addition, the inorganic phase change material may have a phase transition temperature, and the phase transition temperature may be -18°C to -23°C.

In some examples, in the inorganic phase change material, the mass fraction of water may be 45% to 86.75%, the mass fraction of the inorganic salt may be 9.25% to 51%, and the mass fraction of the stabilizer may be 0.051% to 1.1%, The mass percentage of the corrosion inhibitor may be 0.5% to 1%, the mass percentage of the nucleating agent may be 0.2% to 1%, and the mass percentage of the styling agent may be 0.3% to 2%.

In some examples, among the inorganic salts, the mass percent of sodium chloride may be 5 to 16 percent, the mass percent of potassium chloride may be 0.25 to 20 percent, and the mass percent of ammonium chloride may be 4 to 15 percent %. In addition, in some examples, in the stabilizer, the mass percentage of clinoptilolite may be 0.5% to 1%, and the mass percentage of the modified nanocopper wire may be 0.01% to 0.1%.

In the inorganic phase change material involved in this embodiment, using the sodium chloride aqueous solution formed by water and sodium chloride as the basic solution can help to obtain a lower phase transition temperature, and potassium chloride and ammonium chloride can form a complex structure of hydration Therefore, the phase transition temperature can be lowered, and the latent heat of the phase transition can be increased, so that the cooling energy release time can be prolonged. In addition, the setting agent can reduce the phase separation phenomenon during the phase change process, and can increase the number of cycles, the nucleating agent can reduce the ice precipitation during the phase change process, thereby reducing the degree of supercooling, and the corrosion inhibitor can It can reduce the corrosion effect of metal. In addition, the modified nano-copper wire has a good dispersing effect, so that the modified nano-copper wire can be uniformly dispersed in the inorganic phase change material, and can improve the thermal conductivity, thereby improving the heat transfer efficiency, while the clinoptilolite can be combined with Salts (eg, sodium chloride, potassium chloride) create cross-linking effects (eg, ionic effects), which in turn can improve cycling stability.

In addition, the combination of the mass percentage of each component in the inorganic phase change material can help to improve the performance of the inorganic phase change material, for example, it can not only improve the latent heat of phase change, but also improve the cycle stability, and can reduce the phase change temperature. In addition, each component in the inorganic phase change material can be uniformly distributed, which can help to further improve the performance of the inorganic phase change material.

In the present embodiment, as described above, the phase transition temperature of the inorganic phase change material may be -18°C to -23°C. For example, the phase transition temperature of the inorganic phase change material may be -18°C, -18.3°C, -18.5°C, -18.8°C, -19°C, -19.3°C, -19.5°C, -19.8°C, -20°C, -21°C °C, -21.5°C, -22°C, -22.5°C or -23°C.

In some examples, in the inorganic phase change material, the mass percent of water may be 45% to 86.75%. For example, the mass percentage can be 45%, 47%, 50%, 53%, 55%, 57%, 60%, 63%, 65%, 67%, 70%, 73%, 75%, 77%, 80% , 83% or 86.75%. In addition, preferably, in the inorganic phase change material, the water may be deionized water.

In this embodiment, as described above, the inorganic salts may include sodium chloride, potassium chloride, and ammonium chloride. In some examples, in inorganic phase change materials, sodium chloride can be used as a binder. Additionally, in some examples, in the inorganic phase change material, the mass percent of sodium chloride may be 5% to 16%. For example, the mass percentage of sodium chloride can be 5%, 6%, 7%, 8%, 9%, 10%, 11%, 12%, 13%, 14%, 15% or 16%.

In some examples, for the purpose of better obtaining a lower phase transition temperature, preferably, the mass percentage of water may be 60% to 77%, and the mass percentage of sodium chloride may be 7% to 11%.

In some examples, the binder and water serve as the base solution for the inorganic phase change material. In other words, in the inorganic phase change material, the aqueous solution formed by water and the binder can be the main material for absorbing or releasing thermal energy. In addition, lower phase transition temperatures can be achieved by using an aqueous solution formed from water and binder as the base solution. In addition, in this embodiment, the base material in the inorganic phase change material is not limited to the above-mentioned sodium chloride, and other types, mass percentages, etc. of the base material can be selected according to the actual required phase change temperature.

In some examples, among inorganic salts, potassium chloride and ammonium chloride and sodium chloride can act as temperature moderators. Additionally, in some examples, potassium chloride and ammonium chloride can form hydrates in inorganic phase change materials. Thereby, the transformation temperature can be lowered, and the latent heat of transformation can be increased.

Specifically, potassium chloride and ammonium chloride can form complex hydrates in inorganic phase change materials in the presence of a certain amount of water. In other words, in inorganic phase change materials, potassium chloride and ammonium chloride can be used as raw materials for hydrate formation. In addition, the increase of the latent heat of the phase change of the inorganic phase change material can improve the storage cold capacity of the inorganic phase change material, and can prolong the cold energy release time of the inorganic phase change material.

In some examples, in the inorganic phase change material, the mass percentage of potassium chloride may be 0.25% to 20%. For example, the mass percentage of potassium chloride can be 0.25%, 0.5%, 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, 11%, 12% %, 13%, 14%, 15%, 16%, 17%, 18%, 19% or 20%. Additionally, in some examples, potassium chloride as a temperature moderator in the inorganic salt can be replaced with sodium nitrate or potassium nitrate.

In some examples, in the inorganic phase change material, the mass percentage of ammonium chloride may be 4% to 15%. For example, the mass percentage of ammonium chloride can be 4%, 5%, 6%, 7%, 8%, 9%, 10%, 11%, 12%, 13%, 14%, 15%, etc.

In some examples, for the purpose of effectively reducing the phase transition temperature of the inorganic phase change material and increasing its latent heat of phase transition, preferably, the mass percentage of ammonium chloride may be 8% to 13%, and the mass percentage of potassium chloride may be 0.5% to 6%.

In this embodiment, as described above, the stabilizer may include clinoptilolite and modified nanocopper wires.

In some examples, the structure between the clinoptilolite molecules can be layered and can be connected by a force. In other examples, clinoptilolite can function as a nucleating agent in an inorganic phase change material, and can act synergistically with the nucleating agent to further reduce the degree of undercooling.

In some examples, clinoptilolite is capable of cross-linking (eg, ionic effects) with salts (eg, potassium chloride and ammonium chloride) in inorganic phase change materials, thereby enabling improved cycling stability. In other examples, clinoptilolite can undergo ionic complexation with sodium chloride and potassium chloride. In other words, clinoptilolite can form ionic complexes with sodium chloride and potassium chloride. Thereby, it can contribute to further improving the cycle stability.

In some examples, the clinoptilolite can be milled for ionic complexation with sodium chloride, potassium chloride, and the like. In some examples, the clinoptilolite particles in the inorganic phase change material can be approximately the same.

In some examples, the mass percentage of clinoptilolite in the inorganic phase change material may be 0.5% to 1%. For example, the mass percentage of clinoptilolite may be 0.5%, 0.55%, 0.6%, 0.65%, 0.7%, 0.75%, 0.8%, 0.85%, 0.9%, 0.95% or 1%. In addition, in some examples, for the purpose of effectively improving the cycle stability of the inorganic phase change material, preferably, the mass percentage of clinoptilolite may be 0.6% to 0.9%.

In some examples, the particle size of the clinoptilolite may be 1 mm to 3 mm. Thereby, the ion complex reaction of clinoptilolite with the sodium chloride and the potassium chloride can be better performed, thereby contributing to the improvement of cycle stability. For example, the particle size of the clinoptilolite may be 1 mm, 1.2 mm, 1.5 mm, 1.7 mm, 2 mm, 2.3 mm, 2.5 mm, 2.8 mm or 3 mm.

In some examples, among inorganic phase change materials, the modified nanocopper wires can improve thermal conductivity and thus improve heat transfer efficiency. In addition, the improvement of the thermal conductivity of the inorganic phase change material can not only increase the cooling rate of the inorganic phase change material during the cooling process and shorten the pre-cooling time, but also improve the phase separation and supercooling of the inorganic phase change material and improve the inorganic phase change material. Cyclic stability of variable materials.

In some examples, modified copper nanowires can be obtained by modifying copper nanowires with special functional groups, so that the modified copper nanowires can have good dispersibility and stability in inorganic systems (eg, inorganic phase change materials).

In some examples, in the inorganic phase change material, the mass percentage of the modified nano-copper wire may be 0.01% to 0.1%. For example, the mass percentage of the modified nano copper wire can be 0.01%, 0.02%, 0.03%, 0.04%, 0.05%, 0.06%, 0.07%, 0.08%, 0.09%, 0.1%.

In some examples, for the purpose of effectively improving the thermal conductivity of the inorganic phase change material and facilitating the dispersion of the modified copper nanowires in the inorganic phase change material, preferably, the mass percentage of the modified copper nanowires can be 0.03% to 0.06%.

In some examples, the diameter of the modified nanocopper wires may be 14 nm to 30 nm. Additionally, in some examples, the length of the modified nanocopper wires may be 20 μm to 30 μm. Thereby, the dispersibility of the modified nano-copper wire can be advantageously improved.

In some examples, the diameter of the modified nanocopper wires may be 15 nm, 16 nm, 17 nm, 18 nm, 19 nm, 20 nm, 21 nm, or 22 nm. Additionally, in some examples, the modified nanocopper wires may be 20 μm, 21 μm, 22 μm, 23 μm, 24 μm, 25 μm, 26 μm, or 27 μm in length.

In some examples, in the inorganic phase change material, the corrosion inhibitor can have the effect of preventing rust, thereby slowing down the rust of the metal, thereby reducing the occurrence of leakage during use.

In some examples, the corrosion inhibitor may include at least one of a steel corrosion inhibitor, an aluminum and aluminum alloy corrosion inhibitor, and a copper and copper alloy corrosion inhibitor. In addition, in some examples, one type of corrosion inhibitor or a mixture of multiple types of corrosion inhibitors may be selected according to actual application scenarios.

In some examples, the corrosion inhibitor may be at least one selected from the group consisting of nitrite, chromate, phosphate, silicate, and sodium benzoate. Thereby, the corrosion inhibitor can have anti-corrosion effect on common metals (eg copper, aluminum, steel, etc.). For example, the corrosion inhibitor can be sodium benzoate, which can prevent rusting of metals such as brass and red copper; the corrosion inhibitor can be sodium chromate, which can prevent rusting of steel metals.

In some examples, in the inorganic phase change material, the mass percentage of the corrosion inhibitor is 0.5% to 1%. For example, the mass percentage of the corrosion inhibitor can be 0.5%, 0.55%, 0.6%, 0.65%, 0.7%, 0.75%, 0.8%, 0.85%, 0.9%, 0.95%, 1%, and the like.

In some examples, in inorganic phase change materials, the nucleating agent can reduce the occurrence of ice precipitation during the phase change process, thereby reducing the degree of subcooling. In addition, the nucleating agent can increase the latent heat of phase transition, so that the cooling energy release time can be prolonged.

In some examples, in the inorganic phase change material, the mass percentage of the nucleating agent may be 0.2% to 1%. For example, the mass percentage of the nucleating agent may be 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9% or 1%.

In some examples, the particle size of the nucleating agent may be 0.5 μm to 5 μm. Therefore, it can be beneficial to reduce the occurrence of supercooling during the phase transformation. For example, the particle size of the nucleating agent may be 0.5 μm, 1 μm, 1.5 μm, 2 μm, 2.5 μm, 3 μm, 3.5 μm, 4 μm, 4.5 μm or 5 μm.

In some examples, preferably, the mass percentage of the nucleating agent may be 0.3% to 0.8%, and in some examples, preferably, the particle size of the nucleating agent may be 1 μm to 3 μm. In this case, the combination of the particle size and the dosage of the nucleating agent can effectively suppress the occurrence of supercooling.

In some examples, the nucleating agent may be at least one selected from the group consisting of sodium tetraborate, sodium silicate, sodium pyrophosphate, silicon dioxide, and diatomaceous earth. In this case, the nucleating agent can not only reduce the degree of supercooling, but also can prevent corrosion of common metals (eg, tin, aluminum, iron, etc.). In other words, the nucleating agent in the inorganic phase change material is not only an anti-supercooling agent but also an effective corrosion inhibitor for common metals (such as tin, aluminum, iron, etc.). For example, sodium tetraborate can be used as a nucleating agent to reduce the occurrence of ice precipitation, and it is a special corrosion inhibitor corresponding to common metals such as tin, aluminum and iron.

In some examples, in inorganic phase change materials, the styling agent can reduce phase separation during the phase change process, thereby increasing the number of cycles. In addition, the setting agent can increase the latent heat of phase transition, which can prolong the cooling energy release time.

In some examples, in the inorganic phase change material, the mass percentage of the styling agent may be 0.3% to 2%. For example, the mass percentage of the styling agent can be 0.3%, 0.4%, 0.5%, 0.6%, 0.8%, 0.8%, 0.9%, 1%, 1.1%, 1.2%, 1.3%, 1.4%, 1.5%, 1.6% , 1.7%, 1.8%, 1.9% or 2%.

In some examples, in the inorganic phase change material, the styling agent may be at least one selected from the group consisting of sodium carboxymethyl cellulose, sodium carboxymethyl cellulose, xanthan gum, and silica. For example, sodium hydroxymethyl cellulose can be used as a styling agent for inorganic phase change materials.

In some examples, there may be a synergistic effect between the styling agent, the modified nanocopper wires, and the clinoptilolite. Thereby, the cycle stability can be effectively improved. For example: in inorganic phase change materials, clinoptilolite can promote the interaction of inorganic salt ions, thereby reducing the phase separation of part of the inorganic salt ions, while the setting agent can further lock the inorganic salt components, thereby further reducing the inorganic phase Generation of phase separation phenomena in changeable materials.

In some examples, the inorganic phase change material can be cooled below the phase change temperature and used as a coolant. Thereby, it can be used for maintaining a constant temperature. In other words, before the inorganic phase change material is used as a cold storage material, a cooling charging process can be performed so that the inorganic phase change material can store cold energy. Additionally, in some examples, the inorganic phase change material may be placed at -25°C to -40°C for cooling.

In some examples, the inorganic phase change material may be composed of water, sodium chloride, potassium chloride, ammonium chloride, clinoptilolite, modified nanocopper wires, corrosion inhibitors, nucleating agents, and styling agents.

In this embodiment, the coordination of the components and their contents in the inorganic phase change material enables the control of the phase change temperature of the inorganic phase change material and the improvement of the latent heat of the phase change of the inorganic phase change material, and also the improvement of the inorganic phase change material. Cycling stability, for example, can improve the stability of phase transition temperature and latent heat of phase transition during the cycling process of the inorganic phase change material, and increase the number of cycles of the inorganic phase change material.

FIG. 1 is a schematic flowchart illustrating a method for preparing an inorganic phase change material according to an example of the present disclosure.

As shown in FIG. 1 , in this embodiment, the preparation method of the inorganic phase change material may include: preparing water, inorganic salts, stabilizers, corrosion inhibitors, nucleating agents and setting agents, and the inorganic salts include sodium chloride, chlorine Potassium chloride and ammonium chloride, the stabilizer includes clinoptilolite and modified nano copper wire (step S10); sodium chloride, potassium chloride and clinoptilolite are ground and added to water, and mixed to form a first mixed solution (step S10) S20); and adding ammonium chloride, a corrosion inhibitor, a modified nano-copper wire, a shaping agent and a nucleating agent to the first mixed solution, and mixing to form a second mixed solution to obtain an inorganic phase change material (step S30). In addition, the inorganic phase change material may have a phase transition temperature, and the phase transition temperature may be -18°C to -23°C.

In some examples, in the inorganic phase change material, the mass fraction of water may be 45% to 86.75%, the mass fraction of the inorganic salt may be 9.25% to 51%, and the mass fraction of the stabilizer may be 0.051% to 1.1%, The mass percentage of the corrosion inhibitor may be 0.5% to 1%, the mass percentage of the nucleating agent may be 0.2% to 1%, and the mass percentage of the styling agent may be 0.3% to 2%.

In some examples, inorganic salts can include sodium chloride, potassium chloride, and ammonium chloride. Additionally, in some examples, the stabilizer includes clinoptilolite and modified nanocopper wires.

In some examples, among the inorganic salts, the mass percent of sodium chloride may be 5 to 16 percent, the mass percent of potassium chloride may be 0.25 to 20 percent, and the mass percent of ammonium chloride may be 4 to 15 percent %. In addition, in some examples, in the stabilizer, the mass percentage of clinoptilolite may be 0.5% to 1%, and the mass percentage of the modified nanocopper wire may be 0.01% to 0.1%.

In the preparation method of the inorganic phase change material involved in this embodiment, water, sodium chloride, potassium chloride, ammonium chloride, clinoptilolite, modified nano-copper wire, corrosion inhibitor, nucleating agent and setting agent are mixed As a raw material, to prepare inorganic phase change materials with high thermal melting and good stability. Among them, sodium chloride, potassium chloride and clinoptilolite are processed by grinding, in this case, not only can make sodium chloride, potassium chloride and clinoptilolite powder, but also can promote clinoptilolite and clinoptilolite by grinding Sodium chloride and potassium chloride undergo ion complexation, so that the cycle stability of the inorganic phase change material can be improved, so as to prepare an inorganic phase change material with high latent heat of phase change and good cycle stability.

In some examples, in step S10, water, inorganic salts, stabilizers, corrosion inhibitors, nucleating agents and shaping agents may be weighed as raw materials for preparing the inorganic phase change material.

In some examples, the corrosion inhibitor may be at least one selected from the group consisting of nitrite, chromate, phosphate, silicate, and sodium benzoate. Thereby, the rusting effect on common metals (eg, red copper, brass, etc.) can be reduced.

In some examples, the nucleating agent may be at least one selected from the group consisting of sodium tetraborate, sodium silicate, sodium pyrophosphate, silicon dioxide, and diatomaceous earth. Thereby, not only the degree of supercooling can be reduced, but also common metals (eg, tin, aluminum, iron, etc.) can be prevented from rusting.

In some examples, the styling agent may be at least one selected from the group consisting of sodium carboxymethyl cellulose, sodium carboxymethyl cellulose, xanthan gum, and silica. Thereby, the occurrence of the phase separation phenomenon during the phase transformation can be reduced, so that the number of cycles of use can be increased.

In some examples, the modified nano-copper wires may have a diameter of 14 nm to 30 nm and a length of 20 μm to 30 μm.

In some examples, in step S20, sodium chloride, potassium chloride and clinoptilolite are ground. In this case, sodium chloride, potassium chloride and clinoptilolite can be powdered, and since the molecules of clinoptilolite are connected by a certain force in a layered structure, by combining with sodium chloride, potassium chloride The grinding can promote the ionic complexation of clinoptilolite with sodium chloride and potassium chloride. In some examples, in step S20, the sodium chloride, potassium chloride and clinoptilolite are ground uniformly, then added to water and mixed uniformly to form the first mixed solution. In some examples, the first mixed solution can be formed by mixing uniformly by mechanical stirring or magnetic stirring.

In some examples, the clinoptilolite may be co-milled with sodium chloride and potassium chloride in step S20. In addition, in some examples, in step S20, sodium chloride and potassium chloride may be mixed, and then clinoptilolite may be added for grinding treatment. Thereby, clinoptilolite can be ion-complexed better with sodium chloride and potassium chloride.

In some examples, in step S20, the sodium chloride and potassium chloride may be ground and mixed uniformly, and then clinoptilolite is gradually added to continue grinding. In other examples, sodium chloride and potassium chloride can be mixed uniformly and placed in a grinder (eg, a sand mill, a ball mill, etc.), and then the clinoptilolite is gradually added and ground.

In some examples, in step S20, the clinoptilolite may be ground to 1 mm to 3 mm. Thereby, the ion complex reaction of clinoptilolite with the sodium chloride and the potassium chloride can be better performed, thereby contributing to the improvement of cycle stability.

In some examples, in step S30, ammonium chloride, a corrosion inhibitor, a modified nano-copper wire, a sizing agent and a nucleating agent are sequentially added to the first mixed solution and mixed evenly to form the second mixed solution. For example, ammonium chloride, sodium benzoate, modified nano-copper wires, sodium hydroxymethyl cellulose and sodium tetraborate can be added in sequence to the first mixed solution and mixed uniformly to form the second mixed solution.

In some examples, in step 30, the stirring process may be maintained. Thus, the components in the prepared inorganic phase change material can be uniformly dispersed, thereby helping to improve the performance of the prepared inorganic phase change material. In other words, in step 30, stirring can be performed while adding to obtain the second mixed solution. In addition, in some examples, in step S30, the stirring process may be mechanical stirring, magnetic stirring, or the like.

In some examples, in step 30, the second mixed solution may be subjected to ultrasonic treatment to obtain the inorganic phase change material. In addition, in some examples, the second mixed solution may be subjected to ultrasonic agitation (eg, cavitation by an ultrasonic oscillator), so that a further uniformly dispersed inorganic phase change material can be prepared. In other examples, the ultrasonic-treated second mixed liquid may be cooled to room temperature to obtain the inorganic phase change material.

According to the present disclosure, an inorganic phase change material with high latent heat of phase change and good cycle stability and a preparation method thereof can be provided.

In order to further illustrate the present disclosure, the intumescent fire-retardant coating provided by the present disclosure and the preparation method thereof will be described in detail below with reference to the examples, and the beneficial effects achieved by the present disclosure will be fully described with reference to the comparative examples.

【Example】

In Examples 1 to 6 of the present disclosure, for the raw materials for preparing the inorganic phase change material, sodium benzoate is used as a corrosion inhibitor, sodium hydroxymethyl cellulose is used as a styling agent, and sodium tetraborate is used as a nucleating agent.

In each embodiment of embodiment 1 to embodiment 6, firstly, each embodiment prepares raw materials according to the proportions in Table 1 weighing each component, and the total mass of raw materials is 100kg; then, the sodium chloride in the raw materials is , potassium chloride, and clinoptilolite were added to the ball mill in turn and ground for 4 hours to form a uniformly mixed powder; then, the powder was added to deionized water, and stirred to form a first mixed solution, and while continuing to stir, sequentially Add ammonium chloride, sodium benzoate, modified nano-copper wire, sodium hydroxymethyl cellulose and sodium tetraborate to the first mixed solution and mix them uniformly to form a second mixed solution; The two mixed solutions were subjected to ultrasonic treatment and cooled to room temperature to obtain the inorganic phase change materials of Examples 1 to 6.

The performance tests were carried out on the inorganic phase change materials of the respective examples (Example 1 to Example 6) prepared according to Table 1, that is, Examples 1 to Example 1 were respectively tested from the aspects of phase transition temperature, latent heat of phase transition, thermal conductivity, etc. The inorganic phase change material prepared by the formulation of Example 6 was tested for physical and chemical properties according to the phase change material test method (DSC-differential scanning calorimetry), and the cycle times of the inorganic phase change material were detected by a temperature and humidity exchange box to test each implementation. Cycling stability of inorganic phase change materials. The test results are shown in Table 3.

Table 1 Raw material ratios for preparing inorganic phase change materials

【Comparative ratio】

Compared with the above-mentioned examples, the difference between Comparative Examples 1 to 5 is that in Comparative Examples 1 to 5, each component is weighed according to the ratio shown in Table 2 as the raw material of the inorganic phase change material, in addition to Otherwise, the preparation of the inorganic phase change material was carried out in the same manner as in Examples 1 to 5.

Similarly, performance tests were performed on the inorganic phase change materials of each comparative example (Comparative Example 1 to Comparative Example 5) prepared according to Table 1, that is, from the aspects of phase transition temperature, latent heat of phase transition, thermal conductivity, etc. The inorganic phase change materials prepared from the formulations of Examples 1 to 5 were tested for physical and chemical properties according to the phase change material testing method (DSC method), and the inorganic phase change materials of each comparative example were tested by detecting the number of cycles of the inorganic phase change materials. cyclic stability. The test results are shown in Table 3.

Table 2 The ratio of raw materials for preparing inorganic phase change materials

Table 3 Physical and chemical properties of inorganic phase change materials

It can be seen from Table 3 that, compared with the comparative examples, the inorganic phase change materials obtained in the examples (Examples 1 to 6) have higher phase transition latent heat and thermal conductivity, and the The cycle times of the inorganic phase change materials are all not less than 900 times. It can be seen that the inorganic phase change materials obtained in Examples 1 to 6 have high latent heat of phase change and good cycle stability.

In comparison, the inorganic phase change materials obtained in each comparative example (Comparative Example 1 to Comparative Example 5) have low phase transition latent heat and thermal conductivity, and the number of cycles of the inorganic phase change materials of each comparative example does not exceed 100 times.

Although the present disclosure has been specifically described above with reference to the accompanying drawings and embodiments, it should be understood that the above description does not limit the present disclosure in any form. Those skilled in the art can make modifications and changes of the present disclosure as required without departing from the essential spirit and scope of the present disclosure, and these modifications and changes all fall within the scope of the present disclosure.

Claims (10)

1. An inorganic phase change material, characterized in that:

the method comprises the following steps: water, inorganic salt, a stabilizer, a corrosion inhibitor, a nucleating agent and a setting agent, wherein the inorganic salt comprises sodium chloride, potassium chloride and ammonium chloride, the stabilizer comprises clinoptilolite and modified nano copper wires, the inorganic phase-change material has a phase-change temperature of-18 ℃ to-23 ℃,

in the inorganic phase change material, the mass percent of water is 45-86.75%;

the mass fraction of the inorganic salt is 9.25 to 51 percent, and in the inorganic salt, the mass fraction of the sodium chloride is 5 to 16 percent, the mass fraction of the potassium chloride is 0.25 to 20 percent, and the mass fraction of the ammonium chloride is 4 to 15 percent;

the mass fraction of the stabilizer is 0.051-1.1%, in the stabilizer, the mass fraction of the clinoptilolite is 0.5-1%, and the mass fraction of the modified nano copper wire is 0.01-0.1%;

the mass percentage of the corrosion inhibitor is 0.5 to 1 percent;

the mass percent of the nucleating agent is 0.2-1%;

the mass percentage of the setting agent is 0.3-2%.

2. The inorganic phase change material of claim 1, wherein:

the corrosion inhibitor is at least one selected from nitrite, chromate, phosphate, silicate and sodium benzoate, the nucleating agent is at least one selected from sodium tetraborate, sodium silicate, sodium pyrophosphate, silicon dioxide and diatomite, and the setting agent is at least one selected from sodium carboxymethylcellulose, xanthan gum and white carbon black.

3. The inorganic phase change material of claim 1, wherein:

the clinoptilolite forms an ionic complex with the sodium chloride and the potassium chloride.

4. The inorganic phase change material of claim 1, wherein:

the diameter of the modified nano copper wire is 14nm to 30nm, the length of the modified nano copper wire is 20 mu m to 30 mu m, and the particle size of the clinoptilolite is 1mm to 3 mm.

5. The inorganic phase change material of claim 1, wherein:

the inorganic phase change material is cooled to below the phase change temperature and used as a coolant.

6. The inorganic phase change material of claim 1, wherein:

in the inorganic phase change material, the potassium chloride and the ammonium chloride are capable of forming a hydrate.

7. A preparation method of an inorganic phase-change material is characterized by comprising the following steps:

the method comprises the following steps:

(a) the copper wire sizing agent comprises water, inorganic salt, a stabilizer, a corrosion inhibitor, a nucleating agent and a sizing agent, wherein the inorganic salt comprises sodium chloride, potassium chloride and ammonium chloride, and the stabilizer comprises clinoptilolite and a modified nano copper wire;

(b) grinding the sodium chloride, the potassium chloride and the clinoptilolite, adding the ground sodium chloride, the potassium chloride and the clinoptilolite into water, and mixing to form a first mixed solution; and is

(c) Adding the ammonium chloride, the corrosion inhibitor, the modified nano copper wire, the setting agent and the nucleating agent into the first mixed solution, and mixing to form a second mixed solution so as to obtain an inorganic phase-change material, wherein the inorganic phase-change material has a phase-change temperature of-18 ℃ to-23 ℃,

in the inorganic phase change material, the mass percent of water is 45-86.75%; the mass fraction of the inorganic salt is 9.25 to 51 percent, and in the inorganic salt, the mass fraction of the sodium chloride is 5 to 16 percent, the mass fraction of the potassium chloride is 0.25 to 20 percent, and the mass fraction of the ammonium chloride is 4 to 15 percent; the mass fraction of the stabilizer is 0.051-1.1%, in the stabilizer, the mass fraction of the clinoptilolite is 0.5-1%, and the mass fraction of the modified nano copper wire is 0.01-0.1%; the mass percentage of the corrosion inhibitor is 0.5 to 1 percent; the mass percent of the nucleating agent is 0.2-1%; the mass percentage of the setting agent is 0.3-2%.

8. The method of claim 7, wherein:

in step (c), the stirring treatment is maintained, and the second mixed liquid is subjected to ultrasonic treatment to obtain the inorganic phase change material.

9. The method of claim 7, wherein:

the corrosion inhibitor is at least one selected from nitrite, chromate, phosphate, silicate and sodium benzoate, the nucleating agent is at least one selected from sodium tetraborate, sodium silicate, sodium pyrophosphate, silicon dioxide and diatomite, and the setting agent is at least one selected from sodium carboxymethylcellulose, xanthan gum and white carbon black.

10. The method of claim 7, wherein:

in the step (b), the sodium chloride and the potassium chloride are mixed and then added with the clinoptilolite for grinding treatment.

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