WO2021238112A1

WO2021238112A1 - High-stability composite phase-change gel for medicine cold-chain transportation at 2-8℃

Info

Publication number: WO2021238112A1
Application number: PCT/CN2020/131059
Authority: WO
Inventors: 汤弢; 段昌明
Original assignee: 纯钧新材料(深圳)有限公司; 森曼泰冷链科技(绍兴)有限公司
Priority date: 2020-05-27
Filing date: 2020-11-24
Publication date: 2021-12-02
Also published as: CN111808577A

Abstract

A high-stability composite phase-change gel for medicine cold-chain transportation at 2-8℃, comprising: a phase-change coolant formed by mixing water, an alcohol phase-change material, first-class particles, a pH regulator and anti-settling particles, wherein the mass percent of the water is 5.2%-24.2%, the mass percent of the alcohol phase-change material is 75.2%-94.2%, the mass percent of the first-class particles is 0.1%-2%, the mass percent of the pH regulator is 0.04%-0.8%, the mass percent of the anti-settling particles is 0.3%-1.4%, the alcohol phase-change material is polyol or a mixture of the polyol, the pH regulator is an alkaline substance, and the anti-settling particles are at least one of polyphosphate and polyacrylate; and a nanogel having a three-dimensional network structure with second-class particles as nodes, and the mass ratio of the phase-change coolant to the nanogel is 20: 1 to 25: 1. The high-stability composite phase-change gel for medicine cold-chain transportation at 2-8℃ is high in phase-change latent heat and good in cycling stability.

Description

Highly stable composite phase change gel for cold chain transportation of medicine at 2-8℃

Technical field

The present disclosure relates to a high-stability composite phase change gel used for medical cold chain transportation at 2-8°C.

Background technique

With the rapid development of modern logistics and the increasing demand for cold chain pharmaceuticals, pharmaceutical cold chain logistics has also received more attention. In particular, during the medical cold chain transportation process, the temperature and fluctuation range need to be strictly controlled to store or transport drugs, vaccines, blood products and other items to ensure their quality and effectiveness. Phase change energy storage technology has a large energy storage density and a phase change process. The temperature is approximately constant temperature and the output energy is stable. Coupled with the cold chain transportation of medicines, it can keep the temperature cold, save energy and reduce consumption.

In addition, the main working medium in the phase change energy storage technology system is the phase change material, which directly determines the quality of cold chain transportation. Therefore, the development of phase change cold storage agents with suitable phase change temperature range, high latent heat value, low subcooling, no phase separation and good cycle stability will greatly promote the development of the medical cold chain. At present, inorganic hydrated salts and organic phase change materials are often used in pharmaceutical cold chain transportation of phase change materials. However, inorganic hydrated salts have disadvantages such as phase separation and easy leakage, while organic phase change materials also have disadvantages such as low latent heat and flammability.

Summary of the invention

The present disclosure was completed in view of the above-mentioned state of the art, and its purpose is to provide a high-stability composite phase-change gel for medical cold chain transportation at 2-8°C with high latent heat of phase change and good cycle stability.

To this end, the first aspect of the present disclosure provides a high-stability composite phase-change gel for cold chain transportation of medicines at 2-8°C, which includes: a phase-change cold storage agent, which is composed of water and alcohol-based phase-change materials , The first type of particles, pH adjuster and anti-settling particles are mixed, wherein the mass percentage of water is 5.2% to 24.2%, and the mass percentage of the alcoholic phase change material is 75.2% to 94.2%. The mass percentage of a type of particles is 0.1% to 2%, the mass percentage of the pH regulator is 0.04% to 0.8%, the mass percentage of the anti-settling particles is 0.3% to 1.4%, and the alcoholic phase change material Is a polyhydric alcohol or a mixture of polyhydric alcohols, the pH adjusting agent is an alkaline substance, the anti-settling particles are at least one of polyphosphate and polyacrylate; and nanogels, which have the second type The particles are a three-dimensional network structure of nodes, and the mass ratio of the phase change cold storage agent to the nanogel is 20:1 to 25:1. In the first aspect of the present disclosure, the phase change cold storage agent is compounded with a nanogel having a three-dimensional network structure to form a highly stable composite phase change gel, and an alcohol-based phase change material is used to obtain high latent heat of phase change, thereby It can help the composite phase change gel to maintain a fixed shape during the phase change process, and the pH regulator and anti-settling particles can help the first type of particles to be uniformly dispersed, and the second type of particles can help as the nodes of the three-dimensional network structure. The second type of particles are uniformly distributed, which can help reduce the occurrence of phase separation, thereby improving cycle stability.

In addition, in the composite phase change gel involved in the first aspect of the present disclosure, optionally, the alcoholic phase change material is selected from the group consisting of ethylene glycol, butanediol, glycerol, butane erythritol, and pentaerythritol. , At least one of n-decyl alcohol and cetyl alcohol, the pH adjusting agent is at least one selected from sodium hydroxide, potassium hydroxide, calcium hydroxide, ammonia, and the anti-settling particles are sodium polyacrylate, At least one of potassium polyacrylate, sodium tripolyphosphate, sodium hexametaphosphate, and sodium pyrophosphate, the first type of particles and the second type of particles are at least selected from the group consisting of kaolin, talc, and mica powder. A kind of particle. In this case, the composite phase change gel can have a higher latent heat of phase change, maintain a suitable pH, and can facilitate the uniform dispersion of the first type of particles.

In addition, in the composite phase change gel involved in the first aspect of the present disclosure, optionally, the alcoholic phase change material is selected from the group consisting of butanediol, n-decyl alcohol, cetyl alcohol, and ethylene glycol. At least one, the pH adjusting agent is sodium hydroxide, the anti-settling particles are at least one selected from the group consisting of sodium polyacrylate, sodium tripolyphosphate, and sodium hexametaphosphate, the first type of particles and the The second type of particles are kaolin particles. Therefore, the composite phase change gel can have a higher latent heat of phase change, maintain a suitable pH, and can be more conducive to uniform dispersion of the first type of particles.

In addition, in the composite phase change gel involved in the first aspect of the present disclosure, optionally, the nanogel is a polyethylene having a physical crosslinking network with the second type of particles as dynamic crosslinking points. Glycol hydrogel, and the second type of particles are subjected to surface modification treatment, and the physical crosslinking network structure is reversible. As a result, it can facilitate the setting of the composite phase change gel during the phase change process.

In addition, in the composite phase change gel involved in the first aspect of the present disclosure, optionally, the polyethylene glycol hydrogel has a chemical cross-linking network formed by cross-linking polyethylene oxide through chemical bonds. . In this case, the stability of the three-dimensional network structure of the polyethylene glycol hydrogel can be improved, which in turn can contribute to the setting of the composite phase change gel.

In addition, in the composite phase change gel involved in the first aspect of the present disclosure, optionally, the nanogel is radically polymerized by reacting monomers under the action of an initiator and a catalyst, and passes through at least the second It is formed by cross-linking similar particles, wherein the reactive monomer is at least one of polyethylene glycol methyl ether acrylate, polyethylene glycol methacrylate, and polyethylene glycol monomethyl ether monomethacrylate , The initiator is at least one of ammonium disulfate, sodium persulfate, and dibenzoyl peroxide, the catalyst is at least one of tetramethylethylenediamine and methacrylate, and the The mass ratio of the initiator to the reactive monomer is 1:45 to 1:50, the mass ratio of the catalyst to the initiator is 1:1.28 to 1:1.55, and the second type particles react with the The mass ratio of the monomers is 1:66 to 1:72. In this case, a nanogel having a cross-linked network structure can be obtained, thereby being able to maintain a fixed shape during the phase change process.

In addition, in the composite phase change gel involved in the first aspect of the present disclosure, optionally, the phase change cold storage agent has a pH value of 8 to 9, and the first type particles are dispersed in the highly stable Sexual composite phase change gel. This can contribute to the improvement of the phase separation problem.

In addition, in the composite phase change gel involved in the first aspect of the present disclosure, optionally, the particle size of the first type of particles is 2 μm to 5 μm, and the particle size of the second type of particles is 0.8 nm to 0.8 nm. 1.5nm. In this case, the first type of particles can have a sufficient specific surface area and have a low tendency to agglomerate, which can help the first type of particles in the composite phase change gel to be uniformly dispersed, while the second type of particles can have a relatively high Good activity, which can help the second type of particles to be dispersed in the nanogel, which can help the second type of particles to be uniformly dispersed in the composite phase change gel, and therefore can help reduce the phase change generated during the phase change process. Separation phenomenon.

In addition, the second aspect of the present disclosure provides a nanogel, which is formed by radical polymerization of reactive monomers under the action of an initiator and a catalyst and at least crosslinked by the second type of particles, wherein the The reactive monomer is at least one of polyethylene glycol methyl ether acrylate, polyethylene glycol methacrylate, and polyethylene glycol monomethyl ether monomethacrylate, and the initiator is ammonium disulfate, peroxy At least one of sodium sulfate and dibenzoyl peroxide, the catalyst is at least one of tetramethylethylenediamine and methacrylate, and the mass ratio of the initiator to the reaction monomer It is 1:45 to 1:50, the mass ratio of the catalyst to the initiator is 1:1.28 to 1:1.55, and the mass ratio of the second type particles to the reaction monomer is 1:66 to 1. : 72. Thereby, a nanogel having a crosslinked network structure can be formed.

In addition, the third aspect of the present disclosure provides a composite phase change gel, which includes the nanogel described in the preceding paragraph. As a result, a composite phase change gel with stable morphology can be formed.

According to the present disclosure, it is possible to provide a high-stability composite phase-change gel with high latent heat of phase change and good cycle stability for cold chain transportation of medicines at 2-8°C.

Description of the drawings

The present disclosure will now be explained in further detail only through examples with reference to the accompanying drawings, in which:

Fig. 1 is a flow chart showing the preparation method of the high-stability composite phase change gel used for the cold chain transportation of medicines at 2-8°C according to the examples of the present disclosure.

FIG. 2 is a flowchart showing a method for preparing a phase-change cold storage agent according to an example of the present disclosure.

FIG. 3 is a flowchart showing a method for preparing nanogels according to an example of the present disclosure.

FIG. 4(a) is a DSC chart showing the composite phase change gel obtained in Example 1 of the present disclosure.

FIG. 4(b) is a DSC chart showing the composite phase change gel in Example 1 of the present disclosure after 100 cycles.

Figure 5(a) is a DSC chart showing the composite phase change gel obtained in Example 2 of the present disclosure.

Fig. 5(b) is a DSC chart showing the composite phase change gel in Example 2 of the present disclosure after 100 cycles.

FIG. 6(a) is a DSC chart showing the composite phase change gel obtained in Example 3 of the present disclosure.

FIG. 6(b) is a DSC chart showing the composite phase change gel in Example 3 of the present disclosure after 100 cycles.

FIG. 7(a) is a DSC chart showing the composite phase change gel obtained in Example 4 of the present disclosure.

FIG. 7(b) is a DSC chart showing the composite phase change gel in Example 4 of the present disclosure after 100 cycles.

FIG. 8(a) is a DSC chart showing the composite phase change gel obtained in Example 5 of the present disclosure.

FIG. 8(b) is a DSC chart showing the composite phase change gel in Example 5 of the present disclosure after 100 cycles.

Detailed ways

Hereinafter, with reference to the drawings, preferred embodiments of the present disclosure will be described in detail. In the following description, the same symbols are assigned to the same components, and repeated descriptions are omitted. In addition, the drawings are only schematic diagrams, and the ratio of the dimensions between the components or the shapes of the components may be different from the actual ones.

In this embodiment, the high-stability composite phase change gel (hereinafter referred to as the composite phase change gel) used in the cold chain transportation of medicines at 2-8°C according to the present disclosure can be used as a coolant, for example, for refrigerated transportation, biological Cold chain transportation of medicines and blood samples, etc., for example, can be used as a coolant to keep the temperature at 2°C to 8°C.

In some examples, the composite phase change gel involved in the present disclosure can be used for refrigerated transportation, daily refrigerated use, and the like. As a cooling agent for refrigerated transportation, in some examples, it can be used in refrigerated compartments, refrigerated ice bags, mobile cold storage, etc.; as a daily refrigeration use, in some examples, it can be used in cold storage, in-vehicle incubators, etc.

In some examples, the composite phase change gel involved in the present disclosure can be used as a coolant for the storage or transportation of medicines, reagents, vaccines, blood products, biological samples and related products.

In some examples, when the composite phase change gel involved in the present disclosure is used, it can be used as a coolant in a sealed package. Such a cooling bag, for example, can be placed around an object to be insulated (such as food, medicine, etc.) in an incubator to perform insulation work. In addition, the composite phase change gel involved in the present disclosure may be in a high-viscosity gel state, thereby being able to reduce leakage during the phase change process. In addition, the composite phase change gel may have plasticity.

In some examples, the shape of the sealed package filled with the composite phase change gel is plastic. For example, it can be adapted to the shape of the object to be insulated (such as food and medicine), so as to enable the seal filled with the composite phase change gel. The bag fully contacts the object to be insulated, fully exchanges heat with the object to be insulated, and achieves better insulation.

In this embodiment, in some examples, the composite phase change gel involved in the present disclosure may also be a phase change material that maintains a fixed shape during the phase change process, sometimes also referred to as a “shaped phase change material”.

In some examples, the composite phase change gel may be a form-stable phase change material (FSPCM). As a result, the leakage phenomenon during the phase change can be reduced. In some examples, when the composite phase change gel is a shape-stable phase change material, the composite phase change gel can absorb or release heat through a solid-liquid phase transition, and its shape can remain fixed during phase change. Change.

In this embodiment, the high-stability composite phase change gel used for cold chain transportation of medicines at 2-8°C may include a phase change cold storage agent and a nanogel.

In some examples, the phase change temperature of the composite phase change gel may be 2°C to 8°C. Therefore, it can be applied to scenes that need to be maintained at 2°C to 8°C. For example, the phase transition temperature of the composite phase change gel may be 4.3°C. In other examples, the phase change temperature of the composite phase change gel may be 2°C, 3°C, 4°C, 4.5°C, 5°C, 5.5°C, 6°C, 6.5°C, 7°C, 7.5°C, or 8°C.

In some examples, the pH of the composite phase change gel may be weakly alkaline. For example, the pH of the composite phase change gel can be 7.5, 7.6, 7.7, 7.8, 7.9, or 8.

In some examples, the phase change cold storage agent can be used as the main material for storing and releasing cold energy. In addition, in some examples, the phase-change cold storage agent may include water, alcohol-based phase-change materials, first-type particles, pH adjusters, and anti-settling particles.

In some examples, the phase change cold storage agent may include water. In other examples, the mass percentage of water in the phase change cold storage agent may be 5.2% to 24.2%. For example, the mass percentage of water can be 5.2%, 6%, 8%, 10%, 12%, 15%, 18%, 20%, 22%, 24%, or 24.2%. In addition, preferably, in the phase change cold storage agent, the water may be deionized water.

In some examples, the phase change cold storage agent may include an alcohol-based phase change material. In other examples, in the phase change cold storage agent, the mass percentage of the alcoholic phase change material may be 75.2% to 94.2%. For example, the mass percentage of the alcoholic phase change material may be 75.2%, 76%, 78%, 80%, 83%, 85%, 88%, 90%, 92%, 94%, or 94.2%.

In some examples, the alcohol-based phase change material can be used as the main energy storage material in the phase change cold storage agent. In addition, the alcoholic phase change material may be a polyhydric alcohol or a mixture of polyhydric alcohols.

In some examples, the alcoholic phase change material may be at least one of polyols. For example, the alcoholic phase change material may be at least one selected from the group consisting of ethylene glycol, butylene glycol, glycerol, butane erythritol, pentaerythritol, n-decanol, and cetyl alcohol. Therefore, the composite phase change gel can have a higher latent heat of phase change.

In some examples, preferably, the alcoholic phase change material may be at least one selected from butanediol, n-decanol, cetyl alcohol, and ethylene glycol. Therefore, the composite phase change gel can have a higher latent heat of phase change.

In some examples, the phase change cold storage agent may include first type particles. In other examples, in the phase change cold storage agent, the mass percentage of the first type particles may be 0.1% to 2%. For example, the mass percentage of the first type of particles may be 0.1%, 0.2%, 0.5%, 0.8%, 1%, 1.2%, 1.5%, 1.8%, 1.9% or 2%. In addition, the use of the first type of particles can improve the thermal conductivity of the composite phase change gel. In other examples, the first type of particles may be dispersed in a composite phase change gel. Therefore, it can help to improve the problem of phase separation, that is, reduce the occurrence of phase separation in the phase change process.

In some examples, the first type of particles may be particles selected from at least one of kaolin, talc, and mica powder. As a result, it can be advantageous to uniformly disperse the particles of the first type. In addition, preferably, the first type of particles may be kaolin particles (powder particles). Therefore, it can be more favorable for the first type of particles to be uniformly dispersed in the composite phase change gel. In other examples, the particles of the first type may be spherical.

In some examples, the particle size of the first type of particles is 2 μm to 5 μm. Therefore, the particles of the first type can have a sufficient specific surface area and have a low tendency to agglomerate, which can help the particles of the first type in the composite phase change gel to be uniformly dispersed, and therefore can help to reduce the generation of particles in the phase change process. Phase separation phenomenon.

For example, the particle size of the first type of particles is 2 μm, 2.3 μm, 2.5 μm, 2.8 μm, 3 μm, 3.3 μm, 3.5 μm, 3.8 μm, 4 μm, 4.5 μm, or 5 μm.

In some examples, the phase change cold storage agent may include a pH adjuster. In other examples, in the phase change cold storage agent, the mass percentage of the pH adjuster may be 0.04% to 0.8%. For example, the mass percentage of the pH adjusting agent may be 0.04%, 0.05%, 0.1%, 0.15%, 0.2%, 0.25%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7% or 0.8%.

In some examples, the pH adjuster can be used to adjust the pH of the phase change cold storage agent, for example, the pH value of the phase change cold storage agent can be maintained at a predetermined pH value. In addition, in some examples, the predetermined pH value may be 8-9. That is, the pH value of the phase change cold storage agent may be 8-9. For example, the pH value of the phase change cold storage agent may be 8, 8.1, 8.2, 8.3, 8.4, 8.5, 8.6, 8.7, 8.8, 8.9, or 9.

In some examples, when the pH of the phase change cold storage agent is 8 to 9, the surface of the first type particles may carry negative charges. In this case, the surfaces of the particles of the first type can be mutually repelled, so that the particles of the first type can be in a certain dispersion state, which can facilitate the uniform dispersion of the particles of the first type. In addition, the dispersion of the first type of particles can reduce the viscosity, so it can reduce the problem of reduced thermal conductivity due to excessively high viscosity. As a specific example, for example, in the case where the first type of particles are kaolin particles, when the pH of the phase change cold storage agent is 8 to 9, the negative charge on the sides of the kaolin particles will increase, so that the surface of the kaolin particles ( Both the end surface and the side surface of the kaolin particles carry negative charges, which can facilitate the better dispersion of the kaolin particles in the phase change cold storage agent.

In some examples, the pH adjusting agent may be an alkaline substance. In other examples, the pH adjusting agent may be at least one selected from sodium hydroxide, potassium hydroxide, calcium hydroxide, and ammonia. In this way, an appropriate pH can be maintained. In addition, preferably, the pH adjusting agent may be selected from sodium hydroxide. Therefore, it is beneficial to adjust and maintain a proper pH.

In some examples, the pH adjusting agent may be an aqueous solution of an alkaline substance. In other examples, the pH adjusting agent may be at least one selected from sodium hydroxide aqueous solution, potassium hydroxide aqueous solution, calcium hydroxide aqueous solution, and ammonia water. In addition, when the pH adjuster is an aqueous solution, the mass percentage of the pH adjuster in the phase change cold storage agent may refer to the mass percentage of the alkaline substance in the phase change cold storage agent in the aqueous solution.

In some examples, the phase change cold storage agent may include anti-settling particles. In other examples, the mass percentage of anti-settling particles in the phase change cold storage agent may be 0.3% to 1.4%. For example, the mass percentage of anti-settling particles can be 0.3%, 0.4%, 0.5%, 0.6%, 0.7, 08%, 0.9%, 1%, 1.1%, 1.2%, 1.3% or 1.4%. In addition, the anti-settling particles can be dissolved in water and ionized, and the degree of ionization is relatively large.

In some examples, the anti-settling particles may be at least one of polyphosphate and polyacrylate. For example, the anti-settling particles may be polyacrylates with a molecular weight of less than 5000 Da.

In some examples, the anti-settling particles may be at least one of sodium polyacrylate, potassium polyacrylate, sodium tripolyphosphate, sodium hexametaphosphate, and sodium pyrophosphate. As a result, it can be advantageous to uniformly disperse the particles of the first type. In addition, preferably, the anti-settling particles may be at least one of sodium polyacrylate, sodium tripolyphosphate, and sodium hexametaphosphate.

In this embodiment, the anti-settling particles can be ionized in water to form large anions (having a strong negative charge) and small cations (having a weak positive charge) with equal amounts of heterogeneous charges. The anions and cations (large anions and small cations) are adsorbed on An electric double layer is formed on the surface of the first type of particles, which can increase the negative charge on the surface of the first type of particles to cause electrostatic repulsion between the first type of particles, and the steric hindrance effect can be generated, which further enhances the first type of particles. The repulsive effect of, which can form a stable dispersion system. In addition, the anti-settling particles can be dissolved in water and ionized.

In some examples, the phase change cold storage agent may be mixed with water, an alcoholic phase change material, the first type of particles, a pH adjuster, and anti-settling particles.

In some examples, in the phase-change cold storage agent, both the alcohol-based phase-change material and the first-type particles may have hydrophilicity, thereby enabling the phase-change cold storage agent to have good compatibility with the nanogel.

In this embodiment, the blending of the components and ratios enables the phase-change cold storage agent to have good dispersibility, so that the occurrence of sedimentation in the phase-change cold storage agent can be reduced.

In some examples, the nanogel may have a three-dimensional network structure. In some examples, further, the nanogel may have a three-dimensional cross-linked network structure. In addition, when the nanogel has a three-dimensional crosslinked network structure, the crosslinked network structure of the nanogel may be a polymer network structure. In addition, the three-dimensional network structure of the nanogel can take the second type of particles as nodes.

In some examples, the second type of particles may be particles selected from at least one of kaolin, talc, and mica powder. In other examples, the second type of particles and the first type of particles may be composed of the same material. Therefore, it can be advantageous to improve the compatibility between the phase change cold storage agent and the nanogel. In addition, the second type of particles and the first type of particles may also be composed of different materials.

In some examples, the second type of particles may be kaolin particles. In other examples, the second type of particles and the first type of particles are both kaolin particles.

In some examples, the size of the second type of particles may be smaller than the size of the first type of particles. In some examples, the second type of particles may be nano-sized particles, and the first type of particles may be micron-sized particles. In this case, the particles of the first type and the second type of particles can be dispersed in the composite phase change gel, and therefore can help reduce the phase separation phenomenon generated during the phase change process.

In some examples, the particle size of the second type of particles may be 0.8 nm to 1.5 nm. As a result, the second type of particles can have better activity, which can facilitate the dispersion of the second type of particles in the nanogel, and thus can help the second type of particles to be uniformly dispersed in the composite phase change gel, so it can have Helps reduce the phase separation phenomenon produced in the phase change process.

In some examples, the second type of particles may be rod-shaped (or cylindrical). In addition, the particle size of the second type of particles may refer to the diameter of the second type of particles.

In some examples, the aspect ratio (ratio of height to particle size) of the second type of particles may be 200:1 to 400:1. For example, the aspect ratio of the second type of particles may be 200:1, 220:1, 250:1, 280:1, 300:1, 320:1, 350:1, 380:1, or 400:1.

In some examples, the second type of particles may be surface modified. As a result, the binding force between the second type particles and the polymer can be improved. For example, the second type of particles can be modified with a silane coupling agent. In addition, the second type of particles treated with surface modification can have better dispersibility.

In some examples, the nanogel may be a polyethylene glycol hydrogel with a physically cross-linked network structure. As a result, it can facilitate the setting of the composite phase change gel during the phase change process. In addition, the physical cross-linking network can be reversible. This can help the failed nanogel to recover its shape and mechanical strength. In other examples, in the physical cross-linking network, the second type of particles may be dynamic cross-linking points.

In some examples, the polyethylene glycol hydrogel may have a chemically cross-linked network formed by cross-linking with chemical bonds. In this case, the stability of the three-dimensional network structure of the polyethylene glycol hydrogel can be improved, which in turn can contribute to the setting of the composite phase change gel.

In some examples, the polyethylene glycol hydrogel may include a chemical cross-linking network formed by polyethylene oxide (PEO). In other examples, polyethylene oxide molecular chains can intersperse with each other to form a reversible secondary network structure.

In addition, the polyethylene oxide segment in the polyethylene oxide side chain or the non-hydroxyl group (such as methyl, methoxy, amino, acrylate, etc.) of the polyethylene oxide end group passes through the end Physical interactions (such as hydrogen bonds, van der Waals forces, etc.) can be cross-linked with the second type of particles as nodes to form a physical cross-linked network.

In some examples, the nanogel may be formed by free-radical polymerization of reactive monomers under the action of an initiator and a catalyst, and at least cross-linked by the second type of particles. In this case, a nanogel having a cross-linked network structure can be obtained, thereby being able to maintain a fixed shape during the phase change process. In addition, the reactive monomers can undergo free radical polymerization and crosslinking through the action of initiators and catalysts in water to form nanogels.

In some examples, the reactive monomer may be at least one of polyethylene glycol methyl ether acrylate, polyethylene glycol methacrylate, and polyethylene glycol monomethyl ether monomethacrylate. Thus, polyethylene glycol hydrogel can be formed. In addition, in some examples, the reactive monomers can be polycondensed to form a long chain structure and then crosslinked to form a three-dimensional network structure.

In some examples, the molecular weight of the reactive monomer may be 400 Da to 600 Da. This can contribute to improving the gelation efficiency of nanogel preparation. For example, the number average molecular weight of the reactive monomer can be 400 Da, 420 Da, 440 Da, 460 Da, 480 Da, 500 Da, 520 Da, 540 Da, 560 Da, 580 Da, or 600 Da. In the present disclosure, the molecular weight of the reactive monomer may be an index average molecular weight.

In some examples, the initiator may be at least one of ammonium disulfate, sodium persulfate, and dibenzoyl peroxide, and the catalyst may be at least one of tetramethylethylenediamine and methacrylate. In this way, it is possible to cause the reaction monomer to undergo a radical polymerization reaction.

In some examples, the mass ratio of initiator to reactive monomer can be 1:45 to 1:50, and the mass ratio of catalyst to initiator can be 1:1.28 to 1:1.55. The ratio of the second type of particles to reactive monomer The mass ratio can be from 1:66 to 1:72. As a result, it is possible to facilitate the radical polymerization reaction and the formation of nanogels.

In some examples, the mass ratio of initiator to reactive monomer may be 1:45, 1:46, 1:47, 1:48, 1:49, or 1:50. In addition, in some examples, the mass ratio of the catalyst to the initiator may be 1:1.28, 1:1.3, 1:1.35, 1:1.4, 1:1.45, 1:1.5, or 1:1.55. In other examples, the mass ratio of the second type of particles to the reactive monomer may be 1:66, 1:67, 1:68, 1:69, 1:70, 1:71, or 1:72.

In addition, in this embodiment, in some examples, the nanogel may be formed by radical polymerization of reactive monomers under the action of an initiator and a catalyst and at least crosslinked by the second type of particles. Among them, the reactive monomer can be at least one of polyethylene glycol methyl ether acrylate, polyethylene glycol methacrylate, and polyethylene glycol monomethyl ether monomethacrylate, and the initiator can be ammonium disulfate At least one of sodium persulfate and dibenzoyl peroxide, the catalyst can be at least one of tetramethylethylenediamine and methacrylate, and the mass ratio of initiator to reactive monomer can be 1 ﹕45 to 1:50, the mass ratio of catalyst to initiator can be 1:1.28 to 1:1.55, and the mass ratio of the second type of particles to reaction monomer can be 1:66 to 1:72. Thereby, a nanogel having a crosslinked network structure can be formed.

In this embodiment, the nanogel may have good thermal and mechanical stability, for example, when the storage modulus (G') and loss modulus (G") of the nanogel do not increase more than 50% , The thermal stability and mechanical properties of the nanogel are only slightly reduced, and the loss factor (tanδ) remains almost unchanged. As a result, the cycle stability of the composite phase change gel can be improved.

In this embodiment, the composite phase change gel may include the aforementioned nanogel. As a result, a composite phase change gel with stable morphology can be formed.

In this embodiment, in the composite phase change gel, the mass ratio of the phase change cold storage agent to the nanogel may be 20:1 to 25:1. For example, the mass ratio of phase change cold storage agent to nanogel can be 20:1, 21:1, 22:1, 23:1, 24:1, or 25:1.

In some examples, if the mass ratio of the phase change cold storage agent to the nanogel is less than 20:1, the composite phase change gel is likely to reduce the unit energy storage density due to the excessive content of the nanogel, which means that the composite phase change will condense. The latent heat of the gel phase change is reduced; if the mass ratio of the phase change cold storage agent to the nanogel is greater than 25:1, the composite phase change gel is likely to be unable to completely cover the phase change cold storage agent due to too little nanogel content, thus making the composite phase The changing gel is easy to leak during the phase change.

In some examples, the composite phase change gel may be formed by mixing a phase change cold storage agent and a nanogel. In other examples, the composite phase change gel may be formed by mixing a phase change cold storage agent and a nanogel to form a gel.

In some examples, if the phase change cold storage agent has good dispersibility, the phase change cold storage agent can maintain the dispersibility for a long time (for example, one day), thereby being able to form a composite phase change gel with good dispersibility with the nanogel.

In some examples, if the phase change cold storage agent has poor dispersibility, the phase change cold storage agent will settle during the gelation process with the nanogel. In this case, the phase change temperature of the composite phase change gel varies with the formation process. It changes due to the precipitation of the phase change cold storage agent. In other examples, during the formation of the composite phase change gel, if the phase change cold storage agent settles, the phase change temperature of the composite phase change gel decreases.

In this embodiment, in the system of the composite phase change gel, the combination of the components and ratios can make the phase change temperature of the composite phase change gel be between 2°C and 8°C, and can have high latent heat of phase change and circulation. The stability is good.

In the composite phase change gel involved in the present disclosure, an alcoholic phase change material is used to obtain high latent heat of phase change, and a phase change cold storage agent is combined with a nanogel having a three-dimensional network structure, which can be beneficial Maintain a fixed shape during the phase change, and the pH regulator and anti-settling particles can help the first type of particles to be uniformly dispersed, and the second type of particles as the nodes of the three-dimensional network structure can help the second type of particles to be evenly distributed. This can help reduce the occurrence of phase separation, thereby improving cycle stability.

In addition, in the composite phase change gel, the nanogel can encapsulate the phase change cold storage agent, and the phase change cold storage agent can be distributed in the three-dimensional network structure of the nanogel. In this case, when the solid-liquid phase transition occurs Through the supporting effect of the three-dimensional network structure of the nanogel, the macroscopic fluidity of the composite phase change gel can be reduced, thereby reducing leakage during the phase change process.

Hereinafter, in conjunction with FIG. 1, FIG. 2 and FIG. 3, the preparation method of the composite phase change gel involved in the example of this embodiment will be described in detail. FIG. 1 is a flowchart showing a method for preparing a composite phase change gel involved in an example of the present disclosure. FIG. 2 is a flowchart showing a method for preparing a phase-change cold storage agent according to an example of the present disclosure. FIG. 3 is a flowchart showing a method for preparing nanogels according to an example of the present disclosure.

In this embodiment, as shown in FIG. 1, the preparation method of the composite phase change gel may include: preparing a phase change cold storage agent and a nanogel (step S100); and mixing the phase change cold storage agent and the nanogel to thereby A composite phase change gel is formed (step S200). In addition, step S100 may include the preparation of a phase change cold storage agent (step S110) and the preparation of a nanogel (step S120). In addition, for the convenience of illustration, FIG. 1 indicates the sequence of step S110 first and step 120 after. However, in fact, in this embodiment, the sequence of step S110 and step 120 is not specifically limited.

In some examples, in step S200, the phase change cold storage agent and the nanogel may be mixed in a predetermined mass ratio. In addition, in some examples, the predetermined mass ratio may be 20:1 to 25:1. In some examples, in step S110, the phase change cold storage agent may be formed by mixing water, alcohol-based phase change material, first-type particles, pH adjuster, and anti-settling particles. Among them, the mass percentage of water can be 5.2% to 24.2%, the mass percentage of alcoholic phase change material can be 75.2% to 94.2%, the mass percentage of the first type of particles can be 0.1% to 2%, and the mass percentage of the pH regulator The percentage can be 0.04% to 0.8%, and the mass percentage of anti-settling particles can be 0.3% to 1.4%. In addition, for the specific description of the phase change cold storage agent, reference may be made to the above description of the phase change cold storage agent in the composite phase change gel.

In some examples, as shown in FIG. 2, in step S110, the alcoholic phase change material and water can be mixed (step S111), and then the first type of particles, pH adjuster, and anti-settling particles can be added and mixed in sequence. To obtain a phase change cold storage agent (step S112). Thus, it can help to obtain the phase change cold storage agent in which the particles of the first type are uniformly dispersed, and further can help to improve the phase separation problem of the composite phase change gel.

In step S110, the first type of particles may be micron-sized particles. For example, in some examples, the first type of particles may be kaolin particles. In other examples, the first type of particles may be micron-sized kaolin particles.

In some examples, the particle size of the first type of particles is 2 μm to 5 μm. Therefore, the particles of the first type can have a sufficient specific surface area and have a low tendency to agglomerate, which can help the particles of the first type in the composite phase change gel to be uniformly dispersed, and therefore can help to reduce the generation of particles in the phase change process. Phase separation phenomenon. For example, the particle size of the first type of particles is 2 μm, 2.3 μm, 2.5 μm, 2.8 μm, 3 μm, 3.3 μm, 3.5 μm, 3.8 μm, 4 μm, 4.5 μm, or 5 μm.

In addition, in some examples, in step S112, a certain viscosity can be reduced by adding a pH adjuster, and then the viscosity can be further reduced by adding anti-settling particles.

In some examples, in step S111, the alcoholic phase change material and water may be mixed by stirring. For example, it can be stirred for 5 minutes (minutes) to 30 minutes at a rotation speed of 60 rad/m to 100 rad/m (revolutions per minute) at room temperature to uniformly mix the alcoholic phase change material and water.

In some examples, in step S112, the first type of particles may be added first, and then the pH adjuster and anti-settling particles may be added. In addition, in some examples, the first type of particles, the pH adjuster, and the anti-settling particles may be added sequentially.

In addition, in some examples, in step S112, the first-type particles, the pH adjuster, and the anti-settling particles may be added while stirring. As a result, it can be advantageous to uniformly disperse the particles of the first type.

In some examples, in step S112, the first type of particles may be added and stirred for 3h (hour) to 6h at a rotation speed of, for example, 300rad/m to 500rad/m, and then ultrasonically dispersed at a frequency of 1000Hz to 1400Hz for 20min to 40min to form the cold storage material. In other examples, in step S112, a pH adjuster and anti-settling particles may be added to the cold storage material at a rotation speed of 500 rad/m to 1500 rad/m, to form a phase change cold storage agent.

In some examples, before step S112, the dosage of the pH adjusting agent and the anti-settling particles can be determined through preliminary experiments to determine the optimal dosage. Specifically, in the preliminary experiment, for example, the viscosity of the cold storage material can be measured at a rotation speed of 500 rad/m to 1500 rad/m, and then 0.1 ml of pH regulator (or anti-settling particles) is added to the cold storage material for each drop. , After stirring evenly, measure the viscosity once until the viscosity reaches the lowest value. At this time, the dosage of pH adjuster (or the dosage of anti-settling particles) is the best dosage.

As described above, step S100 may include a preparation step of nanogel (step S120). In addition, nanogels can be formed by radical polymerization and crosslinking of reactive monomers.

In some examples, in step S120, as shown in FIG. 3, the preparation of nanogels may include the following steps: preparing reactive monomers, initiators, catalysts, and second-type particles as raw materials for preparation (step S121); The second type particles are mixed with water to form a mixed solution (step S122); and the mixed solution and water are mixed with the reactive monomers in a predetermined ratio, and an initiator and a catalyst are sequentially added to form a reaction system to cause free radical polymerization and crosslinking A nanogel is formed (step S123). Thus, through the above steps S121 to S123, a nanogel can be obtained. In addition, in step 120, the mass ratio of the raw material to the water is 1:10 to 1:11.

In some examples, in the raw materials prepared in step S121, the mass percentage of the reactive monomer may be 93.6% to 94.3%. Therefore, it can be beneficial to increase the reaction rate of free radical polymerization, and the prepared nanogel can have a certain mechanical strength. For example, the mass percentage of the reactive monomer can be 93.6%, 93.7%, 93.8%, 93.9%, 94%, 94.1%, 94.2%, or 94.3%.

In some examples, in the preparation raw materials in step S121, the mass percentage of the initiator may be 1.9% to 2.1%. Thus, it can be advantageous to increase the reaction rate of radical polymerization. For example, the mass percentage of the initiator can be 1.9%, 2% or 2.1%.

In some examples, in the raw materials prepared in step S121, the mass percentage of the catalyst may be 2.3% to 2.9%. Therefore, it can be advantageous to catalyze the radical polymerization reaction. For example, the mass percentage of the catalyst may be 2.3%, 2.4%, 2.5%, 2.6%, 2.7%, 2.8%, or 2.9%.

In some examples, in the raw materials prepared in step S121, the mass percentage of the second type of particles may be 1.3% to 1.5%. As a result, it can contribute to the formation of nanogels with good mechanical properties and thermal stability. For example, the mass percentage of particles of the second type may be 1.3%, 1.4%, or 1.5%. In addition, the particles of the second type can be subjected to surface modification treatment, so that the gelation rate can be improved by adding a small amount of the particles of the second type.

In step S121, the second type of particles may be nano-sized particles. In some examples, the second type of particles may be kaolin particles. In other examples, the second type of particles may be nano-sized kaolin particles.

In some examples, the size of the second type of particles may be smaller than the size of the first type of particles. In some examples, the size of the second type of particles may be nano-sized particles, and the size of the first type of particles may be micron-sized particles. In this case, the particles of the first type and the second type of particles can be dispersed in the composite phase change gel, and therefore can help reduce the phase separation phenomenon generated during the phase change process.

In some examples, the particle size of the second type of particles may be 0.8 nm to 1.5 nm. As a result, the second type of particles can have better activity, which can facilitate the dispersion of the second type of particles in the nanogel, and thus can help the second type of particles to be uniformly dispersed in the composite phase change gel, so it can have Helps reduce the phase separation phenomenon produced in the phase change process. For example, the particle size of the second type of particles may be 0.8 nm, 0.9 nm, 1 nm, 1.1 nm, 1.2 nm, 1.3 nm, 1.4 nm, or 1.5 nm.

In some examples, in step S121, the mass ratio of initiator to reactive monomer may be 1:45 to 1:50, and the mass ratio of catalyst to initiator may be 1:1.28 to 1:1.55. The second type of particles The mass ratio to the reactive monomer can be 1:66 to 1:72.

In some examples, in step S121, the reaction monomer may be at least one of polyethylene glycol methyl ether acrylate, polyethylene glycol methacrylate, and polyethylene glycol monomethyl ether monomethacrylate. The initiator is at least one of ammonium disulfate, sodium persulfate, and dibenzoyl peroxide, and the catalyst can be at least one of tetramethylethylenediamine and methacrylate. In addition, for the specific description of the reactive monomer, initiator, catalyst and second type of particles in the preparation method, reference may be made to the description of the composite phase change gel above.

In some examples, before step S121, the second type of particles may be modified with a silane coupling agent (step S10). In other words, the second type of particles can be modified with a silane coupling agent.

In some examples, the step of silane coupling agent modification treatment (step S10) may include mixing the second type of particles with water (step S11), and sequentially adding a modified solvent and a silane coupling agent to form a suspension (step S11). S12); and the suspension is purified to obtain modified second type particles (step S13).

In some examples, in step S11, the second type particles and water may be mixed at a mass ratio of 1:50 to 1:70. For example, in step S101, the second type of particles and water can be in the order of 1:50, 1:52, 1:55, 1:58, 1:60, 1:62, 1:65, 1:68, or 1:70 The mass ratio is mixed.

In some examples, in step S11, ultrasonic dispersion may be performed at a frequency of 1000 Hz to 1400 Hz for 1 h to 2 h, and stirring may be performed at a rotation speed of 300 rad/m to 600 rad/m for 22 h to 28 h, thereby mixing the second-type particles and water.

In some examples, in step S12, the modification solvent may be at least one of ethanol and toluene, and the silane coupling agent may be triethoxyphenylsilane, methyltriethoxysilane, and phenyltrimethoxysilane. At least one of base silanes. As a result, the second type of particles can be modified by the silane coupling agent, and the gelation rate of the nanogel preparation can be improved.

In some examples, in step S12, the mass ratio of the silane coupling agent to the second type particles may be 1:5 to 1:6.

In some examples, in step S12, the suspension may be formed by ultrasonic dispersion treatment and stirring treatment. For example, it can be ultrasonically dispersed at a frequency of 1000 Hz to 1400 Hz for 1 h to 2 h, and then stirred at a rotation speed of 300 rad/m to 600 rad/m for 18 h to 22 h.

In some examples, in step S13, the suspension may be purified to obtain modified second type particles. In other examples, in step S13, optionally, washing and separating the modified second type particles in the suspension with a washing liquid, and repeating it not less than 3 times (for example, 4 times, 5 times, 6 times) Etc.) to purify the modified second type of particles. In addition, the washing liquid may be at least one of ethanol and water.

In some examples, in step S122, the modified second type particles may be mixed with water to form a mixed liquid.

In some examples, in step S122, the mass concentration of particles of the second type in the mixed solution may be 0.8% to 2.9%. For example, the mass concentration of particles of the second type may be 0.8%, 1%, 1.2%, 1.5%, 1.8%, 2%, 2.3%, 2.5%, 2.7%, or 2.9%.

In some examples, in step S123, the predetermined ratio of the mixed liquid to water may be 1:5 to 1:15. As a result, it is possible to facilitate the formation of a reaction system with an increased reaction rate. For example, the predetermined ratio of mixed liquid and water can be 1:5, 1:6, 1:7, 1:8, 1:9, 1:10, 1:11, 1:12, 1:13, 1:14 or 1:15.

In some examples, in step S123, the mixed solution, water, and reactive monomer may be mixed uniformly, and then the initiator is added for stirring, and the catalyst is added after the initiator is dissolved.

In some examples, in step S123, optionally, the mixed solution, water, and reaction monomer are uniformly mixed through ultrasonic dispersion. For example, it can be ultrasonically dispersed at a frequency of 1000 Hz to 1400 Hz for 1 hour to 2 hours.

In some examples, in step S123, the initiator may be added while stirring until it is dissolved, and then the catalyst is added to form a reaction system.

In some examples, in step S123, the reaction system may undergo a radical polymerization reaction at room temperature and undergo crosslinking. In some examples, in step S123, the initial rate of the radical polymerization reaction is fast, the viscosity increases rapidly, and the reaction system can be allowed to fully polymerize by standing for a period of time (for example, 1 day) under room temperature conditions.

In some examples, optionally, the prepared phase change cold storage agent and the nanogel are mixed and stirred to form a composite phase change gel. In other examples, the phase change cold storage agent and the nanogel can be mixed and stirred at a rotation speed of 300 rad/min to 500 rad/min at room temperature for 2 to 6 hours to form a composite phase change gel.

In some examples, in step 123, reactive monomers, initiators, catalysts, and second-type particles may be used as raw materials for the radical polymerization reaction, wherein the mass percentage of reactive monomers may be 93.6% to 94.3%, and the initiator The mass percentage of the catalyst can be 1.9% to 2.1%, the mass percentage of the catalyst can be 2.3% to 2.9%, and the mass percentage of the second type of particles can be 1.3% to 1.5%. In addition, in step S123, the modified second type particles can be used as a crosslinking agent.

In some examples, in step S200, the phase change cold storage agent and the nanogel may be mixed with a mass ratio of 20:1 to 25:1 at room temperature and a rotation speed of 500rad/m to 1500rad/m for 2h to 6h. A composite phase change gel is formed.

In this embodiment, for the specific description of the composite phase change gel prepared by the preparation method, reference may be made to the description of the composite phase change gel above.

In order to further illustrate the present disclosure, the composite phase change gel provided in the present disclosure will be described in detail below in conjunction with examples, and the beneficial effects achieved by the present disclosure will be fully illustrated in conjunction with comparative examples.

FIG. 4(a) is a DSC chart showing the composite phase change gel obtained in Example 1 of the present disclosure. FIG. 4(b) is a DSC chart showing the composite phase change gel in Example 1 of the present disclosure after 100 cycles. Figure 5(a) is a DSC chart showing the composite phase change gel obtained in Example 2 of the present disclosure. Fig. 5(b) is a DSC chart showing the composite phase change gel in Example 2 of the present disclosure after 100 cycles. FIG. 6(a) is a DSC chart showing the composite phase change gel obtained in Example 3 of the present disclosure. FIG. 6(b) is a DSC chart showing the composite phase change gel in Example 3 of the present disclosure after 100 cycles. FIG. 7(a) is a DSC chart showing the composite phase change gel obtained in Example 4 of the present disclosure. FIG. 7(b) is a DSC chart showing the composite phase change gel in Example 4 of the present disclosure after 100 cycles. FIG. 8(a) is a DSC chart showing the composite phase change gel obtained in Example 5 of the present disclosure. FIG. 8(b) is a DSC chart showing the composite phase change gel in Example 5 of the present disclosure after 100 cycles.

In the embodiments of the present disclosure, for the raw material for preparing the phase change cold storage agent, butanediol or ethylene glycol is used as the alcohol phase change material, kaolin or talc is used as the first type of particles, and sodium polyacrylate, hexameta Sodium phosphate or a mixture of the two in equal proportions is used as anti-settling particles, and the pH regulator is sodium hydroxide water, potassium hydroxide or magnesium hydroxide.

For the raw materials for preparing nanogels, polyethylene glycol methyl ether acrylate or polyethylene glycol methacrylate is used as the reactive monomer, kaolin or talc is used as the second type of particles, and sodium persulfate or ammonium disulfate is used. As an initiator, tetramethylethylenediamine or methacrylate is used as a catalyst. Among them, the second type of particles are modified by a silane coupling agent. The specific steps for the modification of the silane coupling agent are as follows: Mix 1.5g of the second type of particles with 100ml of water and ultrasonically disperse them at a frequency of 1200 Hz for 30 minutes, and then rotate at a speed of 600 rad/ Magnetic stirring for one day under m condition, then adding 50ml of ethanol and 5ml of toluene, then adding 0.5ml of triethoxyphenylsilane aqueous solution and dispersing ultrasonically at 1200Hz frequency for 1h, then magnetic stirring at 600rad/m for 20h To form a suspension, ethanol and deionized water are used to separate and wash the second type of particles in the suspension (ie, the second type of particles modified with a silane coupling agent), repeat the washing three times and then dry to obtain the second type Particles are used as raw materials for preparing nanogels.

[Examples]

In each of Examples 1 to 5, first, the phase change cold storage agent of each example is prepared. Specifically, each embodiment prepared the raw materials for the phase change cold storage agent according to the raw material ratio of the phase change cold storage agent in Table 1 (total mass is 100g), and then put the alcoholic phase change material and deionized water at room temperature. Mix and stir at 100rad/m for 30min, then add pH adjuster at 800rad/m and stir for 10min, then add anti-settling particles at 800rad/m and stir for 10min, then at speed of 800rad/m The first type particles were added under the condition of 400rad/m and stirred for 5 hours, and then placed in an ultrasonic disperser to disperse for 40 minutes at a frequency of 1200 Hz, and then the phase change cold storage agents of Examples 1 to 5 were obtained, and the respective implementations were tested The viscosity of the phase change cold storage agent of the example is used to characterize the dispersion performance, and the test results are shown in Table 3.

Next, the nanogels of the respective examples were prepared. Specifically, each embodiment prepares the raw materials for the preparation of nanogels (total mass 58g) according to the raw material ratio of the nanogels in Table 1, and then mixes the second type of particles with 500ml of water to form a mixed solution for the first The second type particles are dispersed in water, then, the mixed solution and water are mixed with the reaction monomer in a ratio of 1:10, and ultrasonically dispersed at a frequency of 1200 Hz for 1 hour. Then, the initiator is added while stirring until it is dissolved, and then the catalyst is added at room temperature. The reaction was allowed to stand for one day under the conditions, and then the nanogels of Example 1 to Example 5 were obtained.

Then, the phase change cold storage agent and the nanogel of each example were stirred at a speed of 500 rad/m for 6 hours at room temperature according to the ratio in Table 1 to obtain the composite phase change gel of Example 1 to Example 5.

Performance tests were performed on the composite phase change gels of the various examples (Example 1 to Example 5) prepared according to Table 1. The details are as follows. The phase change temperature, the latent heat of phase change and the cycle stability of the composite phase change gel prepared in each example were tested by step cooling curve and differential scanning calorimetry (DSC); by observing the composite of each example Evaluate whether the phase change gel leaks during the cycle of thawing. Table 4 shows the performance test results of the composite phase change gel prepared in each example.

Table 1 Formula for preparing composite phase change gel

[Comparative ratio]

Compared with the above-mentioned examples, Comparative Examples 1 to 7 are different in that they are prepared according to the formula shown in Table 2 in Comparative Examples 1 to 7, except that the same methods are used in Examples 1 to 5. Preparation of composite phase change gel.

Similarly, the composite phase change gels of each comparative example (Comparative Example 1 to Comparative Example 7) prepared according to Table 2 were tested for performance. The details are as follows. The phase change temperature, the latent heat of phase change and the cycle stability of the composite phase change gel prepared by each comparative example were tested by step cooling curve and differential scanning calorimetry (DSC); by observing the composite of each comparative example Evaluate whether the phase change gel leaks during the cycle of thawing. Table 4 shows the performance test results of the composite phase change gel prepared by each comparative example.

Table 2 The ratio of raw materials for preparing composite phase change gel

Table 3 Viscosity of phase change cold storage agent

To	黏度(mPa·S)Viscosity (mPa·S)
实施例1Example 1	3434
实施例2Example 2	9191
实施例3Example 3	142142
实施例4Example 4	21twenty one
实施例5Example 5	4141
对比例1Comparative example 1	5050
对比例2Comparative example 2	1515
对比例3Comparative example 3	195195
对比例4Comparative example 4	168168
对比例5Comparative example 5	163163
对比例6Comparative example 6	3535
对比例7Comparative example 7	2020

Table 4 Performance of composite phase change gel

It can be seen from Table 3 that the viscosity of the phase change cold storage agent of each example (Example 1 to Example 5) is not higher than 150mPa·S, that is, the phase change cold storage agent of each example has good dispersion performance, so During the formation of the composite phase change gel of each embodiment, the phase transition temperature does not change significantly, which can help each embodiment to obtain a composite phase change gel with a phase transition temperature between 2 and 8°C.

In addition, it can be seen from Table 4 that the phase change temperature of the composite phase change gel obtained in each example (Example 1 to Example 5) is between 2 to 8°C, and the latent heat of phase change is higher than 180kJ/kg. , There is no leakage phenomenon, and the cycle stability is good. Specifically, according to Figure 4 (a) to Figure 8 (b), it can be seen that the phase transition temperature of the composite phase change gel of Example 1 to Example 5 after 100 cycles It is still between 2 to 8°C and the decrease rate of the latent heat of phase change does not exceed 6%.

In summary, the composite phase change gel obtained in each of the examples (Example 1 to Example 5) has high latent heat of phase change, good cycle stability, no leakage, and a phase change temperature of 2 to 8°C. .

In comparison, the composite phase change gel obtained in each comparative example (Comparative Example 1 to Comparative Example 7) cannot simultaneously achieve the performance effects of the composite phase change gel obtained in each of the foregoing embodiments.

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

Claims

A high-stability composite phase change gel for cold chain transportation of medicines at 2-8°C, which is characterized in that:

include:

The phase change cold storage agent is a mixture of water, alcoholic phase change material, first type particles, pH adjuster and anti-settling particles, wherein the mass percentage of water is 5.2% to 24.2%, and the alcoholic phase change The mass percentage of the material is 75.2% to 94.2%, the mass percentage of the first type of particles is 0.1% to 2%, the mass percentage of the pH adjuster is 0.04% to 0.8%, and the mass percentage of the anti-settling particles 0.3% to 1.4%, the alcoholic phase change material is a polyol or a mixture of polyols, the pH adjuster is an alkaline substance, and the anti-settling particles are at least one of polyphosphate and polyacrylate. One kind; and

The nanogel has a three-dimensional network structure with second-type particles as nodes, and the mass ratio of the phase change cold storage agent to the nanogel is 20:1 to 25:1.
The high-stability composite phase change gel according to claim 1, wherein:

The alcoholic phase change material is at least one selected from the group consisting of ethylene glycol, butylene glycol, glycerol, butane erythritol, pentaerythritol, n-decyl alcohol, and cetyl alcohol, and the pH adjusting agent is selected from the group consisting of hydroxides At least one of sodium, potassium hydroxide, calcium hydroxide, and ammonia, and the anti-settling particles are at least one of sodium polyacrylate, potassium polyacrylate, sodium tripolyphosphate, sodium hexametaphosphate, and sodium pyrophosphate, The particles of the first type and the particles of the second type are particles of at least one selected from the group consisting of kaolin, talc, and mica powder.
The high-stability composite phase change gel according to claim 2, characterized in that:

The alcoholic phase change material is at least one selected from butanediol, n-decanol, cetyl alcohol, and ethylene glycol, the pH adjusting agent is sodium hydroxide, and the anti-settling particles are selected from poly At least one of sodium acrylate, sodium tripolyphosphate, and sodium hexametaphosphate, the first type of particles and the second type of particles are kaolin particles, respectively.
The high-stability composite phase change gel according to claim 1, wherein:

The nanogel is a polyethylene glycol hydrogel having a physical crosslinking network with the second type of particles as dynamic crosslinking points, and the second type of particles is subjected to a surface modification treatment, and the physical crosslinking The network is reversible.
The high-stability composite phase change gel according to claim 4, wherein:

The polyethylene glycol hydrogel has a chemical cross-linking network formed by cross-linking polyethylene oxide through chemical bonds.
The high-stability composite phase change gel according to claim 1 or 4, characterized in that:

The nanogel is formed by free radical polymerization of reactive monomers under the action of an initiator and a catalyst and at least crosslinked by the second type of particles,

Wherein, the reactive monomer is at least one of polyethylene glycol methyl ether acrylate, polyethylene glycol methacrylate, and polyethylene glycol monomethyl ether monomethacrylate, and the initiator is two At least one of ammonium sulfate, sodium persulfate, and dibenzoyl peroxide, the catalyst is at least one of tetramethylethylenediamine and methacrylate, and the initiator and the reaction unit The mass ratio of the body is 1:45 to 1:50, the mass ratio of the catalyst to the initiator is 1:1.28 to 1:1.55, and the mass ratio of the second type of particles to the reaction monomer is 1. ﹕66 to 1:72.
The high-stability composite phase change gel according to claim 1, wherein:

The pH of the phase change cold storage agent is 8 to 9, and the first type particles are dispersed in the high stability composite phase change gel.
The high-stability composite phase change gel according to any one of claims 1 to 3, wherein:

The particle size of the first type of particles is 2 μm to 5 μm, and the particle size of the second type of particles is 0.8 nm to 1.5 nm.
A nano gel, which is characterized in that:

It is formed by free radical polymerization of reactive monomers under the action of initiator and catalyst and at least cross-linked by the second type of particles,

Wherein, the reactive monomer is at least one of polyethylene glycol methyl ether acrylate, polyethylene glycol methacrylate, and polyethylene glycol monomethyl ether monomethacrylate, and the initiator is two At least one of ammonium sulfate, sodium persulfate, and dibenzoyl peroxide, the catalyst is at least one of tetramethylethylenediamine and methacrylate, and the initiator and the reaction unit The mass ratio of the body is 1:45 to 1:50, the mass ratio of the catalyst to the initiator is 1:1.28 to 1:1.55, and the mass ratio of the second type of particles to the reaction monomer is 1. ﹕66 to 1:72.
A composite phase change gel, which is characterized in that:

Including the nanogel of claim 9.