CN111808577A

CN111808577A - High-stability composite phase-change gel for cold chain transportation of 2-8 ℃ medicines

Info

Publication number: CN111808577A
Application number: CN202010734546.5A
Authority: CN
Inventors: 汤弢; 段昌明
Original assignee: Sunman Tai Cold Chain Technology Shaoxing Co ltd; Chunjun New Materials Shenzhen Co Ltd
Current assignee: Sunman Tai Cold Chain Technology Shaoxing Co ltd; Chunjun New Materials Shenzhen Co Ltd
Priority date: 2020-05-27
Filing date: 2020-07-27
Publication date: 2020-10-23
Also published as: WO2021238112A1

Abstract

The utility model provides a high stability composite phase transition gel for medicine cold chain transportation of 222 ℃, it includes the phase transition cold-storage agent, it is formed by water, alcohols phase transition material, first class granule, pH regulator and anti-settling particle mixture, wherein, the mass percent of water is 5.2% to 24.2%, the mass percent of alcohols phase transition material is 75.2% to 94.2%, the mass percent of first class granule is 0.1% to 2%, the mass percent of pH regulator is 0.04% to 0.2%, the mass percent of anti-settling particle is 0.3% to 1.4%, alcohols phase transition material is polyol or the mixture of polyol, pH regulator is alkaline material, anti-settling particle is at least one of polyphosphate, polyacrylate; and the nanogel has a three-dimensional network structure with the second type of particles as nodes, and the mass ratio of the phase change coolant to the nanogel is 20: 1 to 25: 1. According to the present disclosure, a high-stability composite phase change gel for cold chain transportation of 222 ℃ medicines, which has high phase change latent heat and good cycle stability, can be provided.

Description

High-stability composite phase-change gel for cold chain transportation of 2-8 ℃ medicines

Technical Field

The disclosure relates to a high-stability composite phase-change gel for cold chain transportation of 222 ℃ medicines.

Background

With the rapid development of modern logistics and the increasing demand of cold-chain pharmaceuticals, the pharmaceutical cold-chain logistics are also paid more attention. Particularly, in the cold chain transportation process of medicines, the temperature and the fluctuation range need to be strictly controlled to store or transport the articles such as medicines, vaccines, blood products and the like so as to ensure the quality and the effect of the articles, the phase change energy storage technology has the advantages of large energy storage density, approximately constant temperature in the phase change process, stable output energy and the like, and the cold chain transportation of coupled medicines can keep cold at constant temperature, save energy and reduce loss.

In addition, the main working medium in the phase-change energy storage technical system is a phase-change material which directly determines the cold chain transportation quality. Therefore, the phase change cold storage agent which is suitable in phase change temperature range, high in latent heat value, low in super-cooling degree, free of phase separation and good in circulation stability is developed, and the phase change cold storage agent has a great boosting effect on development of a medical cold chain. At present, inorganic hydrated salt and organic phase change materials are frequently used in medical cold chain transportation phase change materials, but the inorganic hydrated salt has the defects of phase separation, easy leakage and the like, and the organic phase change material also has the defects of low latent heat, flammability and the like.

Disclosure of 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 a high-stability composite phase-change gel for cold chain transportation of 222 ℃.

Therefore, the first aspect of the disclosure provides a high-stability composite phase-change gel for cold chain transportation of 222 ℃ medicines, which includes a phase-change coolant comprising water, alcohol phase-change materials, first-class particles, a pH regulator and anti-settling particles, wherein the mass percent of the water is 5.2% to 24.2%, the mass percent of the alcohol phase-change materials is 75.2% to 94.2%, the mass percent of the first-class particles is 0.1% to 2%, the mass percent of the pH regulator is 0.04% to 0.2%, the mass percent of the anti-settling particles is 0.3% to 1.4%, the alcohol phase-change materials are polyols or a mixture of polyols, the pH regulator is a basic substance, and the anti-settling particles are at least one of polyphosphate and polyacrylate; and the nanogel has a three-dimensional network structure with the second type of particles as nodes, and the mass ratio of the phase change coolant to the nanogel is 20: 1 to 25: 1. In the first aspect of the disclosure, a phase change coolant and a nanogel with a three-dimensional network structure are compounded to form a high-stability composite phase change gel, and an alcohol phase change material is used to obtain high phase change latent heat, so that the composite phase change gel can be favorably kept in a fixed shape in a phase change process, a pH regulator and anti-settling particles can be favorably used for uniformly dispersing first-class particles, and second-class particles serving as nodes of the three-dimensional network structure can be favorably used for uniformly distributing second-class particles, so that the generation of a phase separation phenomenon can be favorably reduced, and the circulation stability can be improved.

In addition, in the composite phase change gel according to the first aspect of the present disclosure, optionally, the alcohol phase change material is at least one selected from ethylene glycol, butylene glycol, glycerol, erythritol, pentaerythritol, n-decanol, and hexadecanol, the pH adjuster is at least one selected from sodium hydroxide, potassium hydroxide, calcium hydroxide, and ammonia water, the anti-settling particles are at least one selected from sodium polyacrylate, potassium polyacrylate, sodium tripolyphosphate, sodium hexametaphosphate, and sodium pyrophosphate, and the first type particles and the second type particles are particles of at least one selected from kaolin, talc, and mica powder, respectively. In this case, the composite phase-change gel can have a high latent heat of phase change, maintain a suitable pH, and can facilitate uniform dispersion of the first type of particles.

In addition, in the composite phase change gel according to the first aspect of the present disclosure, optionally, the alcohol phase change material is at least one selected from butanediol, decanol, hexadecanol, and ethylene glycol, the pH adjusting agent is sodium hydroxide, the anti-settling particles are at least one selected from sodium polyacrylate, sodium tripolyphosphate, and sodium hexametaphosphate, and the first type particles and the second type particles are kaolin particles, respectively. Therefore, the composite phase change gel can have higher latent heat of phase change, maintain proper pH and be more beneficial to the uniform dispersion of the first type of particles.

In addition, in the composite phase change gel according to the first aspect of the present disclosure, optionally, the nanogel is a polyethylene glycol hydrogel having a physical cross-linked network with the second type of particles as dynamic cross-linking points, and the physical cross-linked network structure is reversible after the second type of particles are subjected to surface modification treatment. Therefore, the composite phase change gel can be shaped in the phase change process.

In addition, in the composite phase change gel according to the first aspect of the present disclosure, optionally, the polyethylene glycol hydrogel has a chemical cross-linked network formed by cross-linking polyethylene oxide with a chemical bond. Under the condition, the stability of the three-dimensional network structure of the polyethylene glycol hydrogel can be improved, and the sizing of the composite phase-change gel can be facilitated.

In addition, in the composite phase-change gel related to the first aspect of the present disclosure, optionally, the nanogel is formed by performing radical polymerization on reactive monomers under the action of an initiator and a catalyst and at least crosslinking through the second type of particles, wherein the reaction monomer is at least one of polyethylene glycol methyl ether acrylate, polyethylene glycol methacrylate and polyethylene glycol methyl 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 mass ratio of the initiator to the reaction monomer is from 1: 45 to 1: 50, the mass ratio of the catalyst to the initiator is from 1: 1.22 to 1: 1.55, the mass ratio of the second type of particles to the reaction monomer is from 1: 66 to 1: 72. In this case, a nanogel having a cross-linked network structure can be obtained, whereby a fixed shape can be maintained during phase transition.

In addition, in the composite phase change gel according to the first aspect of the present disclosure, optionally, the pH of the phase change coolant is 2 to 9, and the first type of particles are dispersed in the high-stability composite phase change gel. Thereby, the problem of phase separation can be advantageously improved.

In addition, in the composite phase change gel according to the first aspect of the present disclosure, optionally, the first type of particles have a particle size of 2 μm to 5 μm, and the second type of particles have a particle size of 0.2nm to 1.5 nm. In this case, the first type of particles can have sufficient specific surface area and low agglomeration tendency, thereby being capable of helping the first type of particles in the composite phase-change gel to be uniformly dispersed, and the second type of particles can have good activity, thereby being capable of helping the second type of particles to be uniformly dispersed in the nanogel, and thus being capable of helping the second type of particles to be uniformly dispersed in the composite phase-change gel, thereby being capable of helping to reduce phase separation phenomenon generated in the phase-change process.

In addition, the second aspect of the present disclosure provides a nanogel, which is formed by the free radical polymerization of reaction monomers under the action of an initiator and a catalyst and at least the crosslinking of the second type of particles, wherein the reaction monomer is at least one of polyethylene glycol methyl ether acrylate, polyethylene glycol methyl acrylate and polyethylene glycol methyl 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 mass ratio of the initiator to the reaction monomer is from 1: 45 to 1: 50, the mass ratio of the catalyst to the initiator is from 1: 1.22 to 1: 1.55, the mass ratio of the second type of particles to the reaction monomer is from 1: 66 to 1: 72. Thereby, a nanogel having a cross-linked network structure can be formed.

Additionally, a third aspect of the present disclosure provides a composite phase change gel comprising the nanogel of the preceding item. This enables the formation of a composite phase-change gel having a stable morphology.

According to the present disclosure, a high-stability composite phase change gel for cold chain transportation of 222 ℃ medicines, which has high phase change latent heat and good cycle stability, can be provided.

Drawings

The disclosure will now be explained in further detail by way of example only with reference to the accompanying drawings, in which

Fig. 1 is a flow chart illustrating a method for preparing a high-stability composite phase-change gel for cold chain transportation of 222 ℃ medicines according to an example of the present disclosure.

Fig. 2 is a flowchart illustrating a method of preparing a phase-change coolant according to an example of the present disclosure.

Fig. 3 is a flow chart illustrating a method of making a nanogel according to examples of the disclosure.

Fig. 4(a) is a DSC diagram showing the complex phase-change gel obtained in example 1 of the present disclosure.

Fig. 4(b) is a DSC diagram showing the composite phase-change gel in example 1 of the present disclosure after 100 cycles.

Fig. 5(a) is a DSC diagram showing a composite phase-change gel obtained in example 2 of the present disclosure.

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

Fig. 6(a) is a DSC diagram showing a composite phase-change gel obtained in example 3 of the present disclosure.

Fig. 6(b) is a DSC diagram showing the composite phase-change gel in example 3 of the present disclosure after 100 cycles.

Fig. 7(a) is a DSC diagram showing a composite phase-change gel obtained in example 4 of the present disclosure.

Fig. 7(b) is a DSC diagram showing the composite phase-change gel in example 4 of the present disclosure after 100 cycles.

Fig. 8(a) is a DSC diagram showing a composite phase-change gel obtained in example 5 of the present disclosure.

Fig. 8(b) is a DSC diagram showing the composite phase-change gel in example 5 of the present disclosure after 100 cycles.

Detailed Description

Hereinafter, preferred embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. In the following description, the same components are denoted by the same reference numerals, and redundant description thereof is omitted. The drawings are schematic and the ratio of the dimensions of the components and the shapes of the components may be different from the actual ones.

In the present embodiment, the high-stability composite phase change gel for cold chain transportation of 222 ℃ medicine (hereinafter, referred to as composite phase change gel) according to the present disclosure can be used as a coolant for cold chain transportation of, for example, cold chain transportation of cold storage, biomedicine, blood samples, and the like, and can be used as a coolant for maintaining a temperature of, for example, 2 ℃ to 2 ℃.

In some examples, the composite phase change gels of the present disclosure may be used for refrigerated transport, daily refrigerated use, and the like. As a coolant for refrigerated transport, in some examples, it may be used in a refrigerator car, a refrigerated ice pack, a mobile freezer, or the like; as a daily refrigerating use, in some examples, it may be used for a refrigerator, a car-mounted incubator, and the like.

In some examples, the composite phase change gel of the present disclosure may be used as a coolant for the storage or transport of pharmaceuticals, reagents, vaccines, blood products, biological samples, and related products.

In some examples, the composite phase change gel of the present disclosure may be used as a coolant in a sealed package. Such a cooling bag can be placed around an object to be insulated (e.g., food, medicine, etc.) in an incubator to perform an insulation operation, for example. In addition, the composite phase change gel according to the present disclosure may be in a high viscosity gel state, thereby being capable of reducing a leakage phenomenon during a phase change process. In addition, the composite phase-change gel may have plasticity.

In some examples, the shape of the sealed bag filled with the composite phase-change gel is plastic, for example, the shape of the sealed bag filled with the composite phase-change gel can be adapted to the shape of the object to be insulated (for example, food or medicine), so that the sealed bag filled with the composite phase-change gel can be in sufficient contact with the object to be insulated, and can exchange heat with the object to be insulated sufficiently, thereby achieving better insulation.

In this embodiment, in some examples, the composite phase change gel according to the present disclosure may also be a phase change material that maintains a fixed shape during the phase change process, sometimes referred to as a "shape-stabilized phase change material".

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

In the embodiment, the high-stability composite phase-change gel for cold-chain transportation of 222 ℃ medicines can comprise a phase-change coolant and a nanogel.

In some examples, the phase transition temperature of the composite phase change gel may be 2 ℃ to 2 ℃. Therefore, the method can be applied to scenes needing to be maintained at 2-2 ℃. For example, the phase transition temperature of the composite phase change gel may be 4.3 ℃. In other examples, the phase transition temperature of the composite phase change gel may be 2 ℃, 3 ℃, 4 ℃, 4.5 ℃, 5 ℃, 5.5 ℃, 6 ℃, 6.5 ℃, 7 ℃, 7.5 ℃ or 2 ℃.

In some examples, the pH of the composite phase change gel may be weakly basic. For example, the pH of the composite phase change gel may be 7.5, 7.6, 7.7, 7.2, 7.9, or 2.

In some examples, the phase change coolant may serve as a host material for storing and releasing cold. In addition, in some examples, the phase change coolant may include water, alcohol phase change materials, first type particles, a pH adjuster, and anti-settling particles.

In some examples, the phase change coolant may include water. In other examples, the mass percentage of water in the phase change coolant may be 5.2% to 24.2%. For example, the mass percentage of water may be 5.2%, 6%, 2%, 10%, 12%, 15%, 12%, 20%, 22%, 24%, or 24.2%. In addition, preferably, in the phase change coolant, the water may be deionized water.

In some examples, the phase change coolant may include an alcohol phase change material. In other examples, the alcohol phase change material may be 75.2 to 94.2% by mass in the phase change coolant. For example, the mass percentage of the alcohol phase change material may be 75.2%, 76%, 72%, 20%, 23%, 25%, 22%, 90%, 92%, 94%, or 94.2%.

In some examples, the alcohol phase change material may serve as a primary energy storage material in the phase change coolant. In addition, the alcohol-based phase change material may be a polyol or a mixture of polyols.

In some examples, the alcoholic phase change material may be at least one of a polyol. For example, the alcohol-based phase change material may be at least one selected from the group consisting of ethylene glycol, butylene glycol, glycerin, erythritol, pentaerythritol, decanol, and hexadecanol. Therefore, the composite phase change gel can have high phase change latent heat.

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

In some examples, the phase change coolant may include a first type of particles. In other examples, the first type of particles may be 0.1 to 2% by mass in the phase change coolant. For example, the mass percentage of the first type of particles may be 0.1%, 0.2%, 0.5%, 0.2%, 1%, 1.2%, 1.5%, 1.2%, 1.9%, or 2%. In addition, the first type of particles can improve the heat conduction performance of the composite phase-change gel. In other examples, the first type of particles may be dispersed in a composite phase change gel. Thereby, it is possible to advantageously improve the problem of phase separation, i.e., to reduce the occurrence of a phase separation phenomenon during the phase transition.

In some examples, the first type of particles may be particles selected from at least one of kaolin, talc, mica powder. Thereby, uniform dispersion of the first type of particles can be facilitated. Further, preferably, the first type of particles may be kaolin particles (powder particles). Therefore, the first type particles can be more favorably and uniformly dispersed in the composite phase-change gel. In other examples, the first type of particles may be spherical.

In some examples, the first type of particles have a particle size of 2 μm to 5 μm. Therefore, the first type of particles can have enough specific surface area and low agglomeration tendency, so that the first type of particles in the composite phase-change gel can be uniformly dispersed, and the phase separation phenomenon generated in the phase-change process can be reduced.

For example, the first type of particles have a particle size of 2 μm, 2.3 μm, 2.5 μm, 2.2 μm, 3 μm, 3.3 μm, 3.5 μmm, 3.2 μm, 4 μm, 4.5 μm, or 5 μm.

In some examples, the phase change coolant may include a pH adjuster. In other examples, the pH adjustor may be 0.04% to 0.2% by mass in the phase-change coolant. For example, the mass percentage of the pH adjuster 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 0.2%.

In some examples, the pH adjusting agent may be used to adjust the pH of the phase change coolant, for example, the pH of the phase change coolant may be at a predetermined pH and maintained at the predetermined pH. Additionally, in some examples, the predetermined pH value may be 2 to 9. That is, the phase change coolant may have a pH of 2 to 9. For example, the phase change coolant may have a pH of 2, 2.1, 2.2, 2.3, 2.4, 2.5, 2.6, 2.7, 2.2, 2.9, or 9.

In some examples, the first type of particle surface may carry a negative charge when the phase change coolant has a pH of 2 to 9. In this case, the surfaces of the first type particles can be made repulsive to each other, so that the first type particles can be in a certain dispersed state, whereby uniform dispersion of the first type particles can be facilitated. In addition, the first-type particles are dispersed to reduce the viscosity, so that the problems of reduction of heat conductivity and the like caused by overhigh viscosity can be reduced. As one specific example, for example, in the case that the first type particles are kaolin particles, when the pH of the phase change coolant is 2 to 9, the negative charges on the side surfaces of the kaolin particles are increased, so that the surfaces of the kaolin particles (including the end surfaces and the side surfaces of the kaolin particles) are negatively charged, thereby facilitating better dispersion of the kaolin particles in the phase change coolant.

In some examples, the pH adjuster may be an alkaline substance. In other examples, the pH adjuster may be at least one selected from sodium hydroxide, potassium hydroxide, calcium hydroxide, and ammonia water. This enables the appropriate pH to be maintained. In addition, preferably, the pH adjuster may be selected from sodium hydroxide. Thereby, it is advantageous to adjust and maintain a suitable pH.

In some examples, the pH adjuster may be an aqueous solution of a basic substance. In other examples, the pH adjustor may be at least one selected from the group consisting of an aqueous sodium hydroxide solution, an aqueous potassium hydroxide solution, an aqueous calcium hydroxide 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 coolant may refer to the mass percentage of the alkaline substance in the aqueous solution in the phase change coolant.

In some examples, the phase change coolant may include anti-settling particles. In other examples, the anti-settling particles may be 0.3 to 1.4% by mass in the phase change coolant. For example, the mass percentage of the anti-settling particles may be 0.3%, 0.4%, 0.5%, 0.6%, 0.7, 02%, 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 ionization degree is larger.

In some examples, the anti-settling particles may be at least one of polyphosphate, polyacrylate. For example, the anti-settling particles may be a polyacrylate having 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. Thereby, a uniform dispersion of the first type of particles can be facilitated. 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 a large anion (having a strong negative charge) and a small cation (having a weak positive charge) with the same amount of heterogeneous charges, and the anions and cations (the large anion and the small cation) are adsorbed on the surface of the first type of particles to form an electric double layer, so that the negative charge on the surface of the first type of particles can be increased to generate electrostatic repulsion between the first type of particles, and steric hindrance effect can be generated to further enhance the repulsion between the first type of particles, thereby forming a stable dispersion system. In addition, the anti-settling particles can be dissolved in water to be ionized.

In some examples, the phase change coolant may be formed by mixing water, alcohol phase change material, first type particles, a pH adjuster, and anti-settling particles.

In some examples, in the phase change coolant, the alcohol phase change material and the first type of particles may have hydrophilicity, thereby enabling good compatibility of the phase change coolant with the nanogel.

In the present embodiment, the phase change coolant has good dispersibility by the combination of the components and the ratio, and the occurrence of sedimentation in the phase change coolant 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, in the case where the nanogel has a three-dimensional cross-linked network structure, the cross-linked network structure of the nanogel may be a polymer network structure. Furthermore, the three-dimensional network structure of the nanogel may have the second type of particle as a junction.

In some examples, the second type of particles may be particles selected from at least one of kaolin, talc, mica powder. In other examples, the second type of particle may be composed of the same material as the first type of particle. Therefore, the compatibility between the phase change cold storage agent and the nanogel can be favorably improved. In addition, the second type of particles may be formed of a different material than the first type of particles.

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

In some examples, the second type of particle may be smaller in size than the first type of particle. In some examples, the second type of particles may be nano-sized particles and the first type of particles may be micro-sized particles. In this case, it can be advantageous for the first type of particles and the second type of particles to be dispersed in the composite phase change gel, and thus it can help to reduce the phase separation phenomenon generated during the phase change.

In some examples, the second type of particle may have a particle size of 0.2nm to 1.5 nm. Therefore, the second type of particles can have better activity, so that the second type of particles can be favorably dispersed in the nanogel, the second type of particles can be favorably and uniformly dispersed in the composite phase-change gel, and the phase separation phenomenon generated in the phase-change process can be favorably reduced.

In some examples, the second type of particle 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 (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 particle may be 200: 1, 220: 1, 250: 1, 220: 1, 300: 1, 320: 1, 350: 1, 320: 1, or 400: 1.

In some examples, the second type of particle may be surface modified. This can improve the bonding strength between the second type particles and the polymer. For example, the second type of particles may be modified with a silane coupling agent. In addition, the surface-modified second type particles can have better dispersibility.

In some examples, the nanogel may be a polyethylene glycol hydrogel having a physically cross-linked network structure. Therefore, the composite phase change gel can be shaped in the phase change process. Additionally, the physically cross-linked network may be reversible. Thereby, the shape and mechanical strength of the failed nanogel can be restored. In other examples, the second type of particles may be dynamic cross-linked sites in a physically cross-linked network.

In some examples, the polyethylene glycol hydrogel may have a chemically crosslinked network formed by crosslinking with chemical bonds. Under the condition, the stability of the three-dimensional network structure of the polyethylene glycol hydrogel can be improved, and the sizing of the composite phase-change gel can be facilitated.

In some examples, in the polyethylene glycol hydrogel, it may include a chemically cross-linked network formed from polyethylene oxide (PEO). In other examples, the polyethylene oxide molecular chains may interpenetrate each other to form a reversible secondary network structure.

In addition, the ends of the non-hydroxyl groups (e.g., methyl, methoxy, amino, acrylate, etc.) of the polyethylene oxide segments or the polyethylene oxide end groups in the polyethylene oxide side chains may be cross-linked by physical interactions (e.g., hydrogen bonding, van der waals forces, etc.) with the second type of particles as the nodes to form a physically cross-linked network.

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

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

In some examples, the reactive monomers may have a molecular weight of 400Da to 600 Da. This can contribute to an improvement in the gelation efficiency of nanogel production. For example, the number average molecular weight of the reactive monomers may be 400Da, 420Da, 440Da, 460Da, 420Da, 500Da, 520Da, 540Da, 560Da, 520Da or 600 Da. In the present disclosure, the molecular weight of the reactive monomer may refer to a number average molecular weight.

In some examples, the initiator may be at least one of ammonium bisulfate, sodium persulfate, dibenzoyl peroxide, and the catalyst may be at least one of tetramethylethylenediamine, methacrylate. This enables radical polymerization of the reactive monomers.

In some examples, the mass ratio of initiator to reaction monomer can be from 1: 45 to 1: 50, the mass ratio of catalyst to initiator can be from 1: 1.22 to 1: 1.55, and the mass ratio of second species of particles to reaction monomer can be from 1: 66 to 1: 72. Thus, radical polymerization can be facilitated and nanogel can be formed.

In some examples, the mass ratio of initiator to reaction monomer can be 1: 45, 1: 46, 1: 47, 1: 42, 1: 49 or 1: 50. In addition, in some examples, the catalyst to priming agent mass ratio can be 1: 1.22, 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 species of particles to the reaction monomer can be 1: 66, 1: 67, 1: 62, 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 the reaction monomers under the action of the initiator and the catalyst and crosslinking of at least the second type of particles. Wherein, the reaction monomer can be at least one of polyethylene glycol methyl ether acrylate, polyethylene glycol methyl acrylate and polyethylene glycol monomethyl ether monomethacrylate, the initiator can be at least one of ammonium bisulfate, sodium persulfate and dibenzoyl peroxide, the catalyst can be at least one of tetramethylethylenediamine and methacrylate, the mass ratio of the initiator to the reaction monomer can be 1: 45 to 1: 50, the mass ratio of the catalyst to the initiator can be 1: 1.22 to 1: 1.55, and the mass ratio of the second type of particles to the reaction monomer can be 1: 66 to 1: 72. Thereby, a nanogel having a cross-linked network structure can be formed.

In the present embodiment, the nanogel may have good thermal and mechanical stability, for example, when the storage modulus (G') and loss modulus (G ") of the nanogel are not increased more than 50%, the thermal and mechanical stability of the nanogel are only slightly decreased, and the loss factor (tan) is almost maintained. This can improve the cycle stability of the composite phase-change gel.

In this embodiment, the composite phase change gel may include the nanogel described above. This enables the formation of a composite phase-change gel having a stable morphology.

In the embodiment, the mass ratio of the phase change cold storage agent to the nanogel in the composite phase change gel can be 20: 1 to 25: 1. For example, the mass ratio of the phase change coolant to the 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 coolant to the nanogel is less than 20: 1, the composite phase change gel is easy to reduce the unit energy storage density due to the excessive content of the nanogel, and the latent heat of phase change of the composite phase change gel is also reduced; if the mass ratio of the phase change coolant to the nanogel is larger than 25: 1, the composite phase change gel is easy to cause the nanogel to have too little content and cannot completely wrap the phase change coolant, so that the composite phase change gel is easy to leak in the phase change process.

In some examples, the composite phase-change gel may be formed by mixing a phase-change coolant with a nanogel. In other examples, the composite phase-change gel may be formed by mixing a phase-change coolant and a nanogel to perform gelling.

In some examples, if the phase change coolant has good dispersibility, the phase change coolant may maintain the dispersibility for a long time (e.g., 1 day), thereby being able to form a composite phase change gel having good dispersibility with the nanogel.

In some examples, if the phase change coolant has poor dispersibility, the phase change coolant may be settled during the gelling process with the nanogel, in which case the phase change temperature of the composite phase change gel is changed along with the settlement of the phase change coolant during the formation process. In other examples, during the formation of the composite phase change gel, if the phase change coolant is settled, the phase change temperature of the composite phase change gel is reduced.

In the present embodiment, in the system of the composite phase change gel, the combination of the components and the ratio can make the phase change temperature of the composite phase change gel between 2 ℃ and 2 ℃, and the composite phase change gel can have high phase change latent heat and good cycle stability.

In the composite phase change gel, the alcohol phase change material is used for obtaining high phase change latent heat, and the phase change coolant is compounded with the nanogel with the three-dimensional network structure, so that the phase change coolant can be beneficial to keeping a fixed shape in the phase change process, the pH regulator and the anti-settling particles can be beneficial to uniformly dispersing the first type of particles, and the second type of particles serving as nodes of the three-dimensional network structure can be beneficial to uniformly distributing the second type of particles, so that the phase separation phenomenon can be favorably reduced, and the circulation stability can be improved.

In addition, in the composite phase-change gel, the nanogel can wrap the phase-change coolant, and the phase-change coolant can be distributed in the three-dimensional network structure of the nanogel, and in this case, when the solid-liquid phase change occurs, the macroscopic fluidity of the composite phase-change gel can be reduced through the supporting effect of the three-dimensional network structure of the nanogel, so that the leakage phenomenon in the phase-change process can be reduced.

Hereinafter, a method for preparing the composite phase change gel according to the example of the present embodiment will be described in detail with reference to fig. 1, 2, and 3. Fig. 1 is a flow chart illustrating a method of making a composite phase change gel according to examples of the present disclosure. Fig. 2 is a flowchart illustrating a method of preparing a phase-change coolant according to an example of the present disclosure. Fig. 3 is a flow chart illustrating a method of making a nanogel according to examples of the disclosure.

In this embodiment, as shown in fig. 1, the method for preparing the composite phase-change gel may include: preparing a phase change coolant and nanogel (step S100); and mixing the phase change coolant and the nanogel to form a composite phase change gel (step S200). In addition, step S100 may include preparation of a phase change coolant (step S110) and preparation of nanogel (step S120). For convenience of illustration, fig. 1 shows the sequence of step S110 before and step S120 after, but actually, in this embodiment, the sequence of step S110 and step S120 is not specifically limited.

In some examples, the phase-change coolant and the nanogel may be mixed at a predetermined mass ratio in step S200. Further, in some examples, the predetermined mass ratio may be 20: 1 to 25: 1. In some examples, in step S110, the phase change coolant may be formed by mixing water, the alcohol phase change material, the first type particles, the pH adjuster, and the anti-settling particles. Wherein, the mass percent of the water can be 5.2-24.2%, the mass percent of the alcohol phase-change material can be 75.2-94.2%, the mass percent of the first type particles can be 0.1-2%, the mass percent of the pH regulator can be 0.04-0.2%, and the mass percent of the anti-settling particles can be 0.3-1.4%. In addition, specific description about the phase change coolant may refer to the above description about the phase change coolant in the composite phase change gel.

In some examples, as shown in fig. 2, in step S110, a phase change cold storage agent may be obtained by mixing an alcohol phase change material and water (step S111), and then sequentially adding and mixing a first type of particles, a pH adjuster, and anti-settling particles (step S112). Therefore, the phase change coolant with uniformly dispersed first-class particles can be obtained, and the phase separation problem of the composite phase change gel can be improved.

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 first type of particles have a particle size of 2 μm to 5 μm. Therefore, the first type of particles can have enough specific surface area and low agglomeration tendency, so that the first type of particles in the composite phase-change gel can be uniformly dispersed, and the phase separation phenomenon generated in the phase-change process can be reduced. For example, the first type of particles have a particle size of 2 μm, 2.3 μm, 2.5 μm, 2.2 μm, 3 μm, 3.3 μm, 3.5 μmm, 3.2 μm, 4 μm, 4.5 μm, or 5 μm.

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

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

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

In addition, in some examples, the first type particles, the pH adjuster, and the anti-settling particles may be added while stirring in step S112. Thereby, uniform dispersion of the first type of particles can be facilitated.

In some examples, in step S112, the first type of particles may be added and stirred for 3 to 6 hours at a rotation speed of, for example, 300 to 500rad/m, and then ultrasonically dispersed, for example, at a frequency of 1000 to 1400Hz for 20 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, for example, at a rotation speed of 500rad/m to 1500rad/m, to form a phase change cold storage agent.

In some examples, the amounts of the pH adjuster and the anti-settling particles may be determined by pre-experiment to determine the optimal amount before step S112. Specifically, in the preliminary experiment, the viscosity of the cold storage material may be measured at a rotation speed of 500rad/m to 1500rad/m, and then 0.1ml of the pH adjuster (or anti-settling particles) is added to the cold storage material drop by drop, and the viscosity is measured once after the stirring is performed until the viscosity reaches the minimum, at which time the amount of the pH adjuster (or anti-settling particles) is the optimum amount.

As described above, step S100 may include a preparation step of nanogel (step S120). In addition, nanogels may be formed from reactive monomers that undergo free radical polymerization and cross-linking.

In some examples, in step S120, as shown in fig. 3, the preparation of the nanogel may include the steps of: preparing reaction monomers, an initiator, a catalyst and second-type particles as preparation raw materials (step S121); mixing the second type particles with water to form a mixed solution (step S122); and mixing the mixed solution and water with the reaction monomer in a predetermined ratio, and sequentially adding an initiator and a catalyst to form a reaction system so as to perform a radical polymerization reaction and crosslink to form the nanogel (step S123). Thus, by the steps S121 to S123 as described above, nanogel can be obtained. In addition, at step 120, the mass ratio of the feedstock to water is between 1: 10 and 1: 11.

In some examples, the mass percentage of the reactive monomer in the preparation raw material of step S121 may be 93.6% to 94.3%. Therefore, the method is beneficial to improving the reaction rate of free radical polymerization, and the prepared nanogel has certain mechanical strength. For example, the mass percent of reactive monomer may be 93.6%, 93.7%, 93.2%, 93.9%, 94%, 94.1%, 94.2%, or 94.3%.

In some examples, the mass percentage of the initiator in the preparation raw material of step S121 may be 1.9% to 2.1%. This can contribute to an increase in the reaction rate of radical polymerization. For example, the mass percentage of initiator may be 1.9%, 2%, or 2.1%.

In some examples, the mass percent of catalyst in the preparation feedstock of step S121 may be 2.3% to 2.9%. Thus, the radical polymerization reaction can be advantageously catalyzed. For example, the mass percent of catalyst may be 2.3%, 2.4%, 2.5%, 2.6%, 2.7%, 2.2%, or 2.9%.

In some examples, the mass percentage of the second type of particles in the preparation raw material of step S121 may be 1.3% to 1.5%. Thus, it can contribute to the formation of nanogels having good mechanical properties and thermal stability. For example, the mass percentage of the second type of particles may be 1.3%, 1.4% or 1.5%. In addition, the second type particles may be subjected to a surface modification treatment, whereby the gelation rate can be increased by adding a small amount of the second type particles.

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

In some examples, the second type of particle may have a particle size of 0.2nm to 1.5 nm. Therefore, the second type of particles can have better activity, so that the second type of particles can be favorably dispersed in the nanogel, the second type of particles can be favorably and uniformly dispersed in the composite phase-change gel, and the phase separation phenomenon generated in the phase-change process can be favorably reduced. For example, the particle size of the second type of particles may be 0.2nm, 0.9nm, 1nm, 1.1nm, 1.2nm, 1.3nm, 1.4nm, or 1.5 nm.

In some examples, in step S121, the mass ratio of the initiator to the reaction monomer can be from 1: 45 to 1: 50, the mass ratio of the catalyst to the initiator can be from 1: 1.22 to 1: 1.55, and the mass ratio of the second type of particles to the reaction monomer can be from 1: 66 to 1: 72.

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

In some examples, before step S121, a silane coupling agent modification treatment may be performed on the second type particles (step S10). That is, the second type of particles may be modified with a silane coupling agent.

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

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

In some examples, in step S11, the second type particles may be mixed with water by ultrasonically dispersing at a frequency of 1000Hz to 1400Hz for 1h to 2h and stirring at a rotational speed of 300rad/m to 600rad/m for 22h to 22 h.

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 at least one of triethoxyphenylsilane, methyltriethoxysilane and phenyltrimethoxysilane. Therefore, the second-type particles can be subjected to silane coupling agent modification treatment, and the gelling rate of the nanogel preparation can be improved.

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

In some examples, in step S12, the suspension may be formed through ultrasonic dispersion treatment and stirring treatment. For example, it may be ultrasonically dispersed at a frequency of 1000Hz to 1400Hz for 1h to 2h, and then stirred at a rotational speed of 300rad/m to 600rad/m for 12h 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, the modified second type of particle in the suspension is optionally washed and separated with a washing solution and repeated no less than 3 times (e.g., 4 times, 5 times, 6 times, etc.) to purify the modified second type of particle. The washing solution may be at least one of ethanol and water.

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

In some examples, in step S122, the mass concentration of the second type particles in the mixed solution may be 0.2% to 2.9%. For example, the mass concentration of the second type of particles may be 0.2%, 1%, 1.2%, 1.5%, 1.2%, 2%, 2.3%, 2.5%, 2.7%, or 2.9%.

In some examples, the predetermined ratio of mixed liquor to water in step S123 can be from 1: 5 to 1: 15. Thus, a reaction system having an increased reaction rate can be advantageously formed. For example, the predetermined ratio of liquid to water can be 1: 5, 1: 6, 1:7, 1: 2, 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 the reaction monomer may be mixed uniformly, and then the initiator may be added to be stirred, and the catalyst may be added after the initiator is dissolved.

In some examples, in step S123, optionally, the mixed liquor, water, and reactive monomer are mixed uniformly via ultrasonic dispersion. For example, the ultrasound may be dispersed for 1h to 2h at a frequency of 1000Hz to 1400 Hz.

In some examples, in step S123, the initiator may be added while stirring until dissolved, and then the catalyst may be added to form the 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 is rapidly increased, and the reaction system can be allowed to stand for a period of time (e.g., 1 day) at room temperature to allow the reaction system to be sufficiently polymerized.

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

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

In some examples, in step S200, the phase change coolant and the nanogel may be mixed at a mass ratio of 20: 1 to 25: 1 at room temperature for 2 to 6 hours at a rotation speed of 500rad/m to 1500rad/m to form the composite phase change gel.

In the present embodiment, specific description of the composite phase-change gel prepared by the preparation method may refer to the description of the composite phase-change gel above. According to the present disclosure, a high-stability composite phase change gel for cold chain transportation of 222 ℃ medicines, which has high phase change latent heat and good cycle stability, can be provided.

To further illustrate the present disclosure, the composite phase change gel provided by the present disclosure is described in detail below with reference to examples, and the advantageous effects achieved by the present disclosure are fully illustrated with reference to comparative examples.

Fig. 4(a) is a DSC diagram showing the complex phase-change gel obtained in example 1 of the present disclosure. Fig. 4(b) is a DSC diagram showing the composite phase-change gel in example 1 of the present disclosure after 100 cycles. Fig. 5(a) is a DSC diagram showing a composite phase-change gel obtained in example 2 of the present disclosure. Fig. 5(b) is a DSC diagram showing the composite phase-change gel in example 2 of the present disclosure after 100 cycles. Fig. 6(a) is a DSC diagram showing a composite phase-change gel obtained in example 3 of the present disclosure. Fig. 6(b) is a DSC diagram showing the composite phase-change gel in example 3 of the present disclosure after 100 cycles. Fig. 7(a) is a DSC diagram showing a complex phase change gel obtained in example 4 of the present disclosure. Fig. 7(b) is a DSC diagram showing the composite phase change gel in example 4 of the present disclosure after 100 cycles. Fig. 8(a) is a DSC diagram showing a composite phase-change gel obtained in example 5 of the present disclosure. Fig. 8(b) is a DSC diagram showing the composite phase-change gel in example 5 of the present disclosure after 100 cycles.

In the embodiment of the disclosure, as for raw materials for preparing the phase change coolant, butanediol or ethylene glycol is used as an alcohol phase change material, kaolin or talcum powder is used as a first type of particles, sodium polyacrylate, sodium hexametaphosphate or a mixture of the sodium polyacrylate and the sodium hexametaphosphate in equal proportion is used as anti-settling particles, and a pH regulator is sodium hydroxide, potassium hydroxide or magnesium hydroxide.

For the raw materials for preparing the nanogel, polyethylene glycol methyl ether acrylate or polyethylene glycol methacrylate is used as a reaction monomer, kaolin or talcum powder is used as a second particle, sodium persulfate or ammonium disulfate is used as an initiator, and tetramethyl ethylene diamine or methacrylate is used as a catalyst. Wherein, the second type of particles are modified by a silane coupling agent, and the specific steps of the modification of the silane coupling agent are as follows: mixing 1.5g of the second-type particles with 100ml of water, ultrasonically dispersing the mixture at the frequency of 1200Hz for 30min, magnetically stirring the mixture for one day at the rotation speed of 600rad/m, adding 50ml of ethanol and 5ml of toluene, adding 0.5ml of triethoxyphenylsilane aqueous solution, ultrasonically dispersing the mixture at the frequency of 1200Hz for 1h, magnetically stirring the mixture for 20h at the rotation speed of 600rad/m to form a suspension, separating and washing the second-type particles (namely the second-type particles modified by the silane coupling agent) in the suspension by using ethanol and deionized water, repeatedly washing the second-type particles for three times, and drying the second-type particles to obtain the second-type particles as raw materials for preparing the nanogel.

[ examples ] A method for producing a compound

In each of embodiments 1 to 5, first, the phase change coolant of each embodiment is prepared. Specifically, each example prepares a preparation raw material (total mass is 100g) of the phase change coolant according to a raw material ratio of the phase change coolant in table 1, then mixing the alcohol phase-change material and deionized water at room temperature and stirring for 30min at the rotating speed of 100rad/m, then adding pH regulator at rotation speed of 200rad/m and stirring for 10min, then adding anti-settling particles at rotation speed of 200rad/m and stirring for 10min, the first type of particles is then added and stirred for 5 hours at a rotation speed of 400rad/m, then placing the mixture into an ultrasonic disperser to disperse for 40min at the frequency of 1200Hz, phase change coolants of examples 1 to 5 were then obtained, and the dispersion properties were characterized by testing the viscosity of the phase change coolant of each example, with the test results shown in table 3.

Next, nanogels of the respective examples were prepared. Specifically, in each example, a raw material for producing a nanogel (total mass: 52g) was prepared in accordance with the raw material mixing ratio of the nanogel in table 1, then, the second type particles were mixed with 500ml of water to form a mixed solution, the second type particles were dispersed in water, then, the mixed solution and water were mixed with the reaction monomer at a ratio of 1: 10, and ultrasonically dispersed at a frequency of 1200Hz for 1 hour, then, the initiator was added while stirring until dissolved, and then, the catalyst was added and allowed to stand at room temperature for one day to perform reaction, thereby obtaining nanogels of examples 1 to 5.

Then, the phase change cold storage agent and the nanogel of each example were stirred at a rotation speed of 500rad/m for 6 hours under room temperature conditions in the ratio of table 1 to obtain composite phase change gels of examples 1 to 5.

The composite phase change gels of the respective examples (example 1 to example 5) prepared according to table 1 were subjected to a performance test. Specifically, the phase change temperature, the phase change latent heat and the cycle stability of the composite phase change gel prepared in each example were respectively tested by a step cooling curve and Differential Scanning Calorimetry (DSC); the leakage problem was evaluated by observing whether the composite phase change gels of the various embodiments leak during the cyclic freeze. The performance test results of the composite phase change gels prepared in the respective examples are shown in table 4.

TABLE 1 formulation for preparing composite phase change gels

[ COMPARATIVE EXAMPLES ]

Comparative examples 1 to 7 are compared with the above examples except that the composite phase change gel was prepared in the same manner as in examples 1 to 5 except that the formulations shown in table 2 were prepared in comparative examples 1 to 7.

Also, the composite phase change gels of the respective comparative examples (comparative example 1 to comparative example 7) prepared according to table 2 were subjected to a performance test. Specifically, the phase change temperature, the phase change latent heat and the cycle stability of the composite phase change gel prepared in each comparative example are respectively tested through a step cooling curve and a Differential Scanning Calorimetry (DSC); the leakage problem was evaluated by observing whether the composite phase change gel of each comparative example was leaking during the cyclic freeze. The results of the performance test of the composite phase change gels prepared in the respective comparative examples are shown in table 4.

TABLE 2 raw material ratio for preparing composite phase-change gel

TABLE 3 viscosity of phase change coolant

	Viscosity (mPa. S)
		Example 1	34
Example 2	91
		Example 3	142
Example 4	21
		Example 5	41
Comparative example 1	50
		Comparative example 2	15
Comparative example 3	195
		Comparative example 4	162
Comparative example 5	163
		Comparative example 6	35
Comparative example 7	20

TABLE 4 Properties of the composite phase-Change gel

As can be seen from table 3, 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, and thus the phase change temperature does not change significantly during the formation of the composite phase change gel of each example, and thus it is possible to contribute to obtaining the composite phase change gel having the phase change temperature between 2 and 2 ℃.

In addition, as can be seen from table 4, the phase transition temperatures of the composite phase change gels obtained in the respective examples (example 1 to example 5) are all between 2 ℃ and 8 ℃, the latent heat of phase transition is higher than 180 kJ/kg, no leakage phenomenon occurs, and the cycle stability is good, specifically, as can be seen from fig. 4(a) to 8(b), the phase transition temperatures of the composite phase change gels of examples 1 to example 5 are still between 2 ℃ and 8 ℃ after 100 cycles, and the decrease rate of the latent heat of phase transition is not more than 6%.

In summary, the composite phase-change gels obtained in the respective examples (examples 1 to 5) have high latent heat of phase change, good cycle stability, no leakage phenomenon and a phase change temperature of 2 to 2 ℃.

In contrast, the composite phase-change gels obtained in the respective comparative examples (comparative example 1 to comparative example 7) cannot simultaneously achieve the performance effects of the composite phase-change gels obtained in the respective examples.

While the present disclosure has been described in detail in connection with the drawings and examples, it should be understood that the above description is not intended to limit the disclosure in any way. Those skilled in the art can make modifications and variations to the present disclosure as needed without departing from the true spirit and scope of the disclosure, which fall within the scope of the disclosure.

Claims

1. A high-stability composite phase-change gel for cold chain transportation of 222 ℃ medicines is characterized in that,

includes

The phase change cold storage agent is formed by mixing water, alcohol phase change materials, 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 materials 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 0.04-0.2%, the mass percent of the anti-settling particles is 0.3-1.4%, the alcohol phase change materials are polyhydric alcohols or a mixture of the polyhydric alcohols, the pH regulator is an alkaline substance, and the anti-settling particles are at least one of polyphosphate and polyacrylate; and

and the nanogel has a three-dimensional network structure with the second type of particles as nodes, and the mass ratio of the phase change coolant to the nanogel is 20: 1 to 25: 1.

2. The high stability composite phase change gel of claim 1,

the alcohol phase change material is at least one selected from ethylene glycol, butanediol, glycerol, erythritol, pentaerythritol, n-decanol and hexadecanol, the pH regulator is at least one selected from sodium hydroxide, potassium hydroxide, calcium hydroxide and ammonia water, the anti-settling particles are at least one selected from sodium polyacrylate, potassium polyacrylate, sodium tripolyphosphate, sodium hexametaphosphate and sodium pyrophosphate, and the first type particles and the second type particles are particles of at least one selected from kaolin, talcum powder and mica powder.

3. The high stability composite phase change gel of claim 2,

the alcohol phase change material is at least one selected from butanediol, decanol, hexadecanol and ethylene glycol, the pH regulator is sodium hydroxide, the anti-settling particles are at least one selected from sodium polyacrylate, sodium tripolyphosphate and sodium hexametaphosphate, and the first type particles and the second type particles are kaolin particles respectively.

4. The high stability composite phase change gel of claim 1,

the nanogel is polyethylene glycol hydrogel with a physical crosslinking network taking the second type of particles as dynamic crosslinking points, and the physical crosslinking network is reversible after the second type of particles are subjected to surface modification treatment.

5. The high stability composite phase change gel of claim 4,

the polyethylene glycol hydrogel has a chemically crosslinked network formed by crosslinking polyethylene oxide with chemical bonds.

6. The high stability composite phase change gel according to claim 1 or 4,

the nanogel is formed by the reaction monomers which undergo free radical polymerization under the action of an initiator and a catalyst and are crosslinked at least through the second particles,

wherein the reaction monomer is at least one of polyethylene glycol methyl ether acrylate, polyethylene glycol methacrylate and polyethylene glycol monomethyl ether methacrylate, the initiator is at least one of ammonium dithionate, sodium persulfate and dibenzoyl peroxide, the catalyst is at least one of tetramethylethylenediamine and methacrylate, the mass ratio of the initiator to the reaction monomer is 1: 45 to 1: 50, the mass ratio of the catalyst to the initiator is 1: 1.22 to 1: 1.55, and the mass ratio of the second type of particles to the reaction monomer is 1: 66 to 1: 72.

7. The high stability composite phase change gel of claim 1,

the pH value of the phase change coolant is 2-9, and the first type of particles are dispersed in the high-stability composite phase change gel.

8. The high stability composite phase change gel according to any one of claims 1 to 3,

the first type of particles have a particle size of 2 to 5 μm and the second type of particles have a particle size of 0.2 to 1.5 nm.

9. A nanogel which is characterized in that,

is prepared by the reaction monomer under the action of initiator and catalyst to generate free radical polymerization and at least to be crosslinked by the second particle,

10. A composite phase-change gel is characterized in that,

comprising the nanogel of claim 9.