Moisture-permeable film, method for producing the same, and use thereof

Abstract

This invention provides a moisture-permeable membrane, its preparation method, and its application. The moisture-permeable membrane includes a base membrane and hybrid particles distributed within the base membrane. The hybrid particles include thermosensitive polymer particles and gold nanomaterials distributed within the thermosensitive polymer particles. In this invention, the moisture-permeable membrane has a high water molecule transfer rate and good moisture permeability, which helps reduce the formation of condensate. Simultaneously, the moisture-permeable membrane responds rapidly to photothermal conversion; when condensate forms, it can be promptly and quickly removed from the membrane surface under certain stimuli, ensuring the membrane's performance.

Description

Technical Field

[0001] This invention belongs to the field of polymer membrane material technology, specifically relating to a moisture-permeable membrane, its preparation method, and its application. Background Technology

[0002] Moisture-permeable membranes possess a certain degree of moisture permeability, enabling efficient and controllable conduction of moisture, thus finding applications in preservation and heat exchange. Food preservation film is a packaging product primarily used for food preservation; typically, it has moderate oxygen and moisture permeability, regulating the oxygen and moisture content around the preserved food while blocking dust and bacteria, thereby extending its shelf life. Total heat exchange membranes, also known as enthalpy exchange membranes, are a crucial component of fresh air systems, effectively improving system energy efficiency, enhancing air quality, and ensuring indoor comfort; they are widely used in various locations requiring ventilation.

[0003] However, during the use of moisture-permeable membranes, whether in preservation or heat exchange, condensation often forms on the membrane surface due to supersaturation of air humidity or temperature changes. The formation of condensation accelerates the spoilage of the preserved products, reduces heat exchange efficiency, accelerates the corrosion and damage of equipment, and affects the performance.

[0004] Therefore, developing a permeable membrane with high water molecule transfer efficiency and the ability to clean condensate from the membrane surface in a timely and rapid manner is an urgent problem to be solved in this field. Summary of the Invention

[0005] To address the shortcomings of existing technologies, the present invention aims to provide a moisture-permeable membrane, its preparation method, and its application. The moisture-permeable membrane exhibits a fast water molecule transfer rate and high response efficiency, which helps reduce condensation formation. Furthermore, when condensation does form, the moisture-permeable membrane can promptly and quickly remove the condensation from its surface under certain stimuli, ensuring the membrane's effectiveness.

[0006] To achieve this objective, the present invention adopts the following technical solution:

[0007] In a first aspect, the present invention provides a moisture-permeable membrane, the moisture-permeable membrane comprising a base membrane and hybrid particles distributed within the base membrane; the hybrid particles comprising thermosensitive polymer particles and gold nanomaterials distributed within the thermosensitive polymer particles.

[0008] In this invention, by adding hybrid particles to the base membrane, a molecular-scale microchannel is formed between the base membrane and the hybrid particles, which promotes the transfer of water molecules, ensures good moisture permeability of the membrane, and helps reduce the formation of condensate. When condensate forms on the surface of the permeable membrane due to factors such as oversaturation, the plasmon resonance effect of the gold nanomaterials generates a large amount of heat when irradiated with near-infrared light, causing a phase transition in the thermosensitive polymer. This leads to the shrinkage of the hybrid particles, increasing the microchannel between the base membrane and the hybrid particles. Furthermore, the hybrid structure of the gold nanomaterials and the thermosensitive polymer particles results in a rapid photothermal conversion response of the hybrid particles, further accelerating the transfer of water molecules and allowing condensate to drain quickly, preventing condensate from affecting the membrane's performance. When near-infrared irradiation is removed, the permeable membrane can quickly return to its pre-shrinkage structure, ensuring the performance of the permeable membrane.

[0009] Secondly, the present invention provides a method for preparing the moisture-permeable membrane described in the first aspect, the method comprising the following steps:

[0010] The raw materials of the base membrane are mixed with hybrid particles to form a membrane, thus obtaining the moisture-permeable membrane.

[0011] Thirdly, the present invention provides an application of the moisture-permeable membrane as described in the first aspect in a food preservation film or a total heat exchange membrane.

[0012] In this invention, the moisture-permeable membrane is used as a preservation film, which helps to improve the preservation effect of the preservation film and delay the spoilage of the preserved products; when used as a total heat exchange membrane, it helps to improve the enthalpy efficiency of the total heat exchange membrane.

[0013] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0014] The moisture-permeable membrane provided by this invention promotes the transfer of water molecules by adding thermosensitive polymer particles and gold nanomaterials to the base membrane, ensuring good moisture permeability and reducing the formation of condensate. Furthermore, the moisture-permeable membrane responds rapidly to photothermal conversion, and when condensate forms, it can promptly and quickly remove the condensate from the membrane surface under certain stimuli, ensuring the membrane's performance. Attached Figure Description

[0015] Figure 1 This is a schematic diagram illustrating the structural changes of the hybrid particles described in this invention before and after near-infrared light irradiation;

[0016] Among them, 1-thermosensitive polymer particles; 2-gold nanomaterials.

[0017] Figure 2 This is a schematic diagram of the structure of the moisture-permeable membrane described in this invention before near-infrared light irradiation;

[0018] Wherein, 1-base film; 2-hybrid particles.

[0019] Figure 3 This is a schematic diagram of the structure of the moisture-permeable membrane described in this invention after near-infrared light irradiation;

[0020] Wherein, 1-base film; 2-hybrid particles. Detailed Implementation

[0021] The technical solution of the present invention will be further illustrated below through specific embodiments. Those skilled in the art should understand that the embodiments described are merely illustrative of the invention and should not be considered as specific limitations thereof. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention. Where specific conditions are not specified in the embodiments of the present invention, conventional conditions or conditions recommended by the manufacturer shall apply. Reagents or instruments whose manufacturers are not specified are all conventional products that can be purchased commercially.

[0022] The present invention provides a moisture-permeable membrane, the moisture-permeable membrane comprising a base membrane and hybrid particles distributed within the base membrane; the hybrid particles comprising temperature-sensitive polymer particles and gold nanomaterials distributed within the temperature-sensitive polymer particles.

[0023] In this invention, by adding hybrid particles to the base membrane, a molecular-scale microchannel is formed between the base membrane and the hybrid particles, which promotes the transfer of water molecules, ensures good moisture permeability of the membrane, and helps reduce the formation of condensate. When condensate forms on the surface of the permeable membrane due to factors such as oversaturation, the plasmon resonance effect of the gold nanomaterials generates a large amount of heat when irradiated with near-infrared light, causing a phase transition in the thermosensitive polymer. This leads to the shrinkage of the hybrid particles, increasing the microchannel between the base membrane and the hybrid particles. Furthermore, the hybrid structure of the gold nanomaterials and the thermosensitive polymer particles results in a rapid photothermal conversion response of the hybrid particles, further accelerating the transfer of water molecules and allowing condensate to drain quickly, preventing condensate from affecting the membrane's performance. When near-infrared irradiation is removed, the permeable membrane can quickly return to its pre-shrinkage structure, ensuring the performance of the permeable membrane.

[0024] It should be noted that the base film in this invention is a non-porous dense film.

[0025] Preferably, the mass ratio of the thermosensitive polymer particles to the gold nanomaterial is (8-20):1, wherein the specific values ​​of (8-20) can be, for example, a range of 8, 8.5, 9, 9.5, 10, 10.5, 11, 11.5, 12, 12.5, 13, 13.5, 14, 14.5, 15, 15.5, 16, 16.5, 17, 17.5, 18, 18.5, 19, 19.5, 20, or any two of these.

[0026] By controlling the mass ratio of thermosensitive polymer particles to gold nanomaterials to be (8-20):1, it is beneficial to further optimize the binding stability of gold nanomaterials and thermosensitive polymer particles, and further improve the water molecule transfer performance and photothermal conversion response speed.

[0027] Preferably, the gold nanomaterial includes at least one of one-dimensional gold nanomaterials and gold nanoparticles.

[0028] In this invention, one-dimensional gold nanomaterials can be classified according to their morphology as at least one of gold nanorods, gold nanotubes, and gold nanowires.

[0029] Preferably, the aspect ratio of the one-dimensional gold nanomaterial is 5 to 20, for example, it can be 5, 5.2, 5.5, 5.8, 6, 6.2, 6.5, 6.8, 7, 7.2, 7.5, 7.8, 8, 8.2, 8.5, 8.8, 9, 9.2, 9.5, 9.8, 10, 10.2, 10.5, 10.8, 11, 11.2, 11.5, 11.8, 12, 12.2, 12.5. The range consisting of 12.8, 13, 13.2, 13.5, 13.8, 14, 14.2, 14.5, 14.8, 15, 15.2, 15.5, 15.8, 16, 16.2, 16.5, 16.8, 17, 17.2, 17.5, 17.8, 18, 18.2, 18.5, 18.8, 19, 19.2, 19.5, 19.8, 20, or any two of these ranges.

[0030] Preferably, the length of the one-dimensional gold nanomaterial is 20nm to 125nm, for example, it can be 20nm, 22nm, 24nm, 26nm, 28nm, 30nm, 32nm, 34nm, 36nm, 38nm, 40nm, 42nm, 44nm, 46nm, 48nm, 50nm, 52nm, 54nm, 56nm, 58nm, 60nm, 62nm, 64nm, 66nm, 68nm, 70nm, 72nm, 74nm, 76nm, 78nm, 80nm, 82nm, 84nm, 86nm, 88nm, 90nm, 92nm, 94nm. The range is 96nm, 98nm, 100nm, 102nm, 105nm, 108nm, 110nm, 112nm, 115nm, 118nm, 120nm, 122nm, 125nm, or any two of these; the diameter is 5nm to 25nm, for example, it can be 5nm, 6nm, 7nm, 8nm, 9nm, 10nm, 11nm, 12nm, 13nm, 14nm, 15nm, 16nm, 17nm, 18nm, 19nm, 20nm, 21nm, 22nm, 23nm, 24nm, 25nm, or any two of these.

[0031] Preferably, the average particle size of the gold nanoparticles is 50nm to 150nm, for example, it can be a range of 50nm, 52nm, 55nm, 58nm, 60nm, 62nm, 65nm, 68nm, 70nm, 72nm, 75nm, 78nm, 80nm, 82nm, 85nm, 88nm, 90nm, 92nm, 95nm, 98nm, 100nm, 102nm, 105nm, 108nm, 110nm, 112nm, 115nm, 118nm, 120nm, 122nm, 125nm, 128nm, 130nm, 132nm, 135nm, 138nm, 140nm, 142nm, 145nm, 148nm, 150nm, or any combination thereof.

[0032] By selecting gold nanoparticles of specific sizes and one-dimensional gold nanomaterials, it is beneficial for the gold nanomaterials to be stably and uniformly dispersed in the temperature-sensitive polymer particles, thereby further promoting the water molecule transfer and moisture permeation rate during the use of the membrane.

[0033] In this invention, the length and diameter of the one-dimensional gold nanomaterial can be observed by transmission electron microscopy (TEM). For example, a transmission electron microscope (Hitachi High-Technologies, model H-7650) can be used to take 10 images at 100,000 to 200,000 times magnification. The diameter and length of 50 one-dimensional gold nanomaterials can be measured on the images using the software attached to the TEM, and the arithmetic mean of these measurements can be used to calculate the length and diameter of the one-dimensional gold nanomaterial.

[0034] The average particle size of the gold nanoparticles can be observed using a transmission electron microscope (TEM). For example, a TEM (Hitachi High-Technologies, model H-7650) can be used to take 10 images at 100,000 to 200,000x magnification. The particle size of 50 gold nanoparticles can be measured on the images using the software attached to the TEM, and the arithmetic mean of these images can be used to calculate the average particle size. Alternatively, the particle size distribution of the raw material can be determined by measuring the particle size distribution, and the particle size corresponding to Dv50 is the average particle size.

[0035] Preferably, the thermosensitive polymer particles comprise amino thermosensitive polymer particles.

[0036] In this invention, gold nanomaterials can coordinate with amino groups in thermosensitive polymers. The gold nanolayers and thermosensitive polymers can be interconnected by sharing lone pair electrons to form coordination covalent bonds or by electrostatic attraction to form ionic bonds, forming an Au-N electron donor-electron acceptor. This allows the gold nanomaterials to be stably dispersed in the thermosensitive polymer particles, thereby further improving the water molecule transfer rate and moisture permeability of the membrane.

[0037] Preferably, the temperature-sensitive polymer particles include at least one of poly(N,N-dimethylaminoethyl methacrylate) (PDMAEMA), poly((N,N-diethylaminoethyl methacrylate)) (PDEAEMA), and their derivatives.

[0038] The derivatives refer to compounds obtained by chemically modifying the molecular structure of the temperature-sensitive polymer particles to introduce new functional groups or change their structure according to actual usage requirements. For example, derivatives of PDMAEMA can be PDMAEMA-N3, β-cyclodextrin-poly(N,N-dimethylaminoethyl methacrylate) (β-CD-PDMAEMA), or HEC-PDMAEMA grafted with hydroxyethyl cellulose (HEC) to form HEC-PDMAEMA grafted polymers, etc.; derivatives of PDEAEMA can be PDEAEMA modified with polyethylene glycol (PEG) or HEC-PDEAEMA grafted with hydroxyethyl cellulose (HEC) to form HEC-PDEAEMA grafted polymers, etc.

[0039] Preferably, the average particle size of the hybrid particles is 200nm to 300nm, for example, it can be a range of 200nm, 205nm, 210nm, 215nm, 220nm, 225nm, 230nm, 235nm, 240nm, 245nm, 250nm, 255nm, 260nm, 265nm, 270nm, 275nm, 280nm, 285nm, 290nm, 295nm, 300nm or any combination thereof.

[0040] By selecting an appropriate average particle size for the hybrid particles, it is beneficial to further improve their compatibility with the film-forming host material, further ensure that the hybrid particles are stably and uniformly dispersed in the polymer film host, further form good micro-channels, and promote the water molecule transfer performance and photothermal conversion response speed.

[0041] In this invention, the average particle size of the hybrid particles can be obtained by particle size distribution testing, scanning electron microscopy (SEM), or transmission electron microscopy (TEM).

[0042] Preferably, the mass ratio of the base film to the hybrid particles is (4-20):1, where the specific values ​​of (4-20) can be, for example, 4, 4.2, 4.4, 4.6, 4.8, 5, 5.2, 5.4, 5.6, 5.8, 6, 6.2, 6.4, 6.6, 6.8, 7, 7.2, 7.4, 7.6, 7.8, 8, 8.2, 8.4, 8.6, 8.8, 9, 9.2, 9.4, 9.6, 9.8, 10, 10.2, 10.5, 10.8, 11. The range consisting of 11.2, 11.5, 11.8, 12, 12.2, 12.5, 12.8, 13, 13.2, 13.5, 13.8, 14, 14.2, 14.5, 14.8, 15, 15.2, 15.5, 15.8, 16, 16.2, 16.5, 16.8, 17, 17.2, 17.5, 17.8, 18, 18.2, 18.5, 18.8, 19, 19.2, 19.5, 19.8, 20, or any two of these ranges.

[0043] By controlling the mass ratio of the base membrane to the hybrid particles to be (4-20):1, it is beneficial for the hybrid particles to be more evenly distributed in the base membrane without agglomeration. At the same time, it can better ensure the airtightness of the moisture permeable membrane and the formation of better micro channels, thereby further improving the water molecule transfer rate and response speed of the moisture permeable membrane.

[0044] Preferably, the thickness of the moisture-permeable membrane is 0.5 μm to 2 μm, for example, it can be a range of 0.6 μm, 0.7 μm, 0.8 μm, 0.9 μm, 1 μm, 1.2 μm, 1.4 μm, 1.6 μm, 1.8 μm, 2 μm or any combination thereof.

[0045] A moisture-permeable thickness of 0.5μm to 2μm is beneficial for suitable mechanical strength and suitable water molecule transport path.

[0046] Secondly, the present invention provides a method for preparing the moisture-permeable membrane described in the first aspect, the method comprising the following steps:

[0047] The raw materials of the base membrane are mixed with hybrid particles to form a membrane, thus obtaining the moisture-permeable membrane.

[0048] Preferably, the raw material of the base film comprises a polymer with a weight-average molecular weight of 40 kDa to 100 kDa (i.e., 40,000 Da to 100,000 Da), for example, a range of 40 kDa, 45 kDa, 50 kDa, 55 kDa, 60 kDa, 65 kDa, 70 kDa, 75 kDa, 80 kDa, 85 kDa, 90 kDa, 95 kDa, 100 kDa, or any combination thereof. The weight-average molecular weight of the polymer can be calculated by GPC.

[0049] The weight-average molecular weight of the polymer is selected in the range of 40 kDa to 100 kDa, which is beneficial to the compactness of the film.

[0050] Preferably, the polymer comprises at least one of polyvinyl alcohol (PVA), polyvinylpyrrolidone (PVP), polyethylene oxide (PEO), polymethacrylic acid (PMAA), polyacrylic acid (PAA), hydroxypropyl methylcellulose (HPMC), or hyaluronic acid (HA).

[0051] It should be noted that the raw materials of the above-mentioned base film may be mixed with antioxidants such as phenolic, phosphorus or sulfur-based agents, metal soaps such as calcium stearate or zinc stearate, ultraviolet absorbers, light stabilizers, antistatic agents, antifogging agents, coloring pigments and other additives as needed.

[0052] Preferably, the method for preparing the hybrid particles includes: mixing a thermosensitive polymer, gold nanomaterials and a solvent to prepare a hybrid particle dispersion, and drying the hybrid particle dispersion to obtain the hybrid particles.

[0053] In this invention, the method for drying the hybrid particle dispersion includes freeze drying.

[0054] Preferably, the preparation method of the hybrid particles includes, for example, dialysis self-assembly technology or microfluidic methods.

[0055] Specifically, the dialysis self-assembly technology involves adding a thermosensitive polymer and gold nanomaterials to an organic solvent and stirring to obtain a mixed slurry. The mixed slurry is then placed into a dialysis bag, which is then placed in deionized water for dialysis. The weight-average molecular weight cutoff of the dialysis bag is 500 Da to 1000 Da. After dialysis for 12 to 24 hours, the dialysis bag is freeze-dried to obtain hybrid particles.

[0056] Specifically, microfluidic technology can be used to add temperature-sensitive polymers and gold nanomaterials to an organic solvent and stir them evenly to obtain a mixed slurry. The mixed slurry is then injected into deionized water at a certain flow rate of 100 rpm to 1000 rpm to obtain a hybrid particle dispersion. The dispersion is then freeze-dried to obtain hybrid particles.

[0057] Specifically, when obtaining the mixed slurry, the present invention does not impose special limitations on the mixing conditions, such as temperature and time, and can adopt appropriate conventional methods in the art; for example, the temperature for mixing the temperature-sensitive polymer, gold nanomaterial and solvent can be 20°C to 40°C, and the mixing can be uniform.

[0058] The method of film formation is not particularly limited in this invention, and existing film formation methods can be used to obtain the film.

[0059] Preferably, the film-forming method includes coating and / or casting.

[0060] In this invention, the coating or casting method is performed on the surface of a substrate, which includes polyethylene terephthalate (PET) release film or glass.

[0061] Preferably, the film formation process further includes drying and peeling steps.

[0062] Thirdly, the present invention provides an application of the moisture-permeable membrane as described in the first aspect in a food preservation film or a total heat exchange membrane.

[0063] In this invention, the moisture-permeable membrane is used as a food preservation film, which helps to improve the preservation effect of the food preservation film and delay the spoilage of the preserved products; when used as a total heat exchange membrane, it can improve the enthalpy efficiency of heat exchange.

[0064] The numerical range described in this invention includes not only the point values ​​listed above, but also any point values ​​within the numerical ranges not listed above. Due to space limitations and for the sake of brevity, this invention will not exhaustively list all the specific point values ​​included in the range.

[0065] The technical solution provided by the present invention will be clearly and completely described below with reference to the accompanying drawings, embodiments and comparative examples. Obviously, the specific embodiments described are only a part of the embodiments of the present invention, and not all of the embodiments.

[0066] All materials used in this invention are commercially available or prepared using conventional methods; unless otherwise specified, the materials used in this invention are as follows:

[0067] Materials of the base film: Polyvinyl alcohol (PVA): weight average molecular weight of 75 kDa, purchased from Anhui Wanwei; Polyacrylic acid (PAA): weight average molecular weight of 120 kDa, purchased from Aladdin Reagent; Hydroxypropyl methylcellulose (HPMC): weight average molecular weight of 200 kDa, purchased from Jiangsu Minglin Chemical Technology Co., Ltd.

[0068] Thermosensitive polymers: Poly(N,N-dimethylaminoethyl methacrylate) (PDMAEMA): weight average molecular weight 5 kDa, purchased from Hangzhou Xinqiao Biotechnology Co., Ltd.; Poly(N,N-diethylaminoethyl methacrylate) (PDEAEMA): weight average molecular weight 10 kDa, purchased from Aladdin Reagent; Poly(N-isopropylacrylamide) (PNIPAM): weight average molecular weight 40 kDa, purchased from Merck Reagent.

[0069] Gold nanomaterials: purchased from Jiangsu Xianfeng Nanomaterials.

[0070] Example 1

[0071] This embodiment provides a moisture-permeable membrane with a thickness of 1.2 μm, comprising a PVA base film and hybrid particles distributed within the PVA base film; the mass ratio of the PVA base film to the hybrid particles is 12:1; the average particle size of the hybrid particles is 240 nm, and the hybrid particles include PDMAEMA particles with a mass ratio of 14:1 and gold nanoparticles (average particle size of 60 nm) dispersed within the PDMAEMA particles.

[0072] This embodiment provides a method for preparing the moisture-permeable membrane, specifically including the following steps:

[0073] (1) PDMAEMA and gold nanoparticles were dispersed in deionized water, and a hybrid particle dispersion with a mass concentration of 10 mg / mL was prepared by microfluidic technology; the hybrid particle dispersion was freeze-dried at -80℃ to obtain the hybrid particles; the specific process of the microfluidic technology is as follows: PDMAEMA and gold nanoparticles were added to dimethyl sulfoxide and stirred evenly to obtain a mixed slurry with a concentration of 1 mg / mL, and the mixed slurry was injected into deionized water at a flow rate of 5 mL / min and a rotation speed of 500 rpm to obtain a 10 mg / mL hybrid particle dispersion, and then the dispersion was freeze-dried to obtain the hybrid particles.

[0074] (2) The hybrid particles, PVA and deionized water obtained in step (1) are mixed at 30°C to obtain a mixed solution with a mass concentration of 6%; then the mixed solution is coated onto the glass surface, dried and peeled at 60°C to obtain the moisture-permeable membrane.

[0075] In this invention, the structural changes of the hybrid particles before and after near-infrared light irradiation are illustrated in the following diagram. Figure 1 As shown, after being irradiated with near-infrared light, the hybrid particles shrink and their size decreases; the structural diagrams of the moisture-permeable membrane before and after near-infrared light irradiation are shown below. Figure 2 (before irradiation) and Figure 3 As shown in the image (after irradiation), after near-infrared light irradiation, the hybrid particles shrink and become smaller, and the micro-channels between the base film and the hybrid particles increase, which is beneficial for accelerating the transfer of water molecules.

[0076] Example 2

[0077] This embodiment provides a moisture-permeable membrane with a thickness of 0.6 μm, comprising a PAA base membrane and hybrid particles distributed within the PAA base membrane; the mass ratio of the PAA base membrane to the hybrid particles is 15:1; the average particle size of the hybrid particles is 200 nm, and the hybrid particles include PDEAEMA particles with a mass ratio of 9:1 and gold nanorods (101 nm in length, 18.8 nm in diameter, and an aspect ratio of 5.4) dispersed within the PDEAEMA particles.

[0078] This embodiment provides a method for preparing the moisture-permeable membrane, and the specific steps are the same as in Embodiment 1.

[0079] Example 3

[0080] This embodiment provides a moisture-permeable membrane with a thickness of 1.8 μm, comprising an HPMC base film and hybrid particles distributed within the HPMC base film; the mass ratio of the HPMC base film to the hybrid particles is 18:1; the average particle size of the hybrid particles is 300 nm, and the hybrid particles include PDMAEMA particles with a mass ratio of 20:1 and gold nanomaterials dispersed within the PDMAEMA particles; the gold nanomaterials include gold nanorods (80 nm in length, 8 nm in diameter, and an aspect ratio of 10) with a mass ratio of 1:1 and gold nanoparticles (average particle size of 120 nm).

[0081] This embodiment provides a method for preparing the moisture-permeable membrane, and the specific steps are the same as in Embodiment 1.

[0082] Example 4

[0083] This embodiment provides a moisture-permeable membrane, which differs from Embodiment 1 only in that the total mass of the PVP base film and the hybrid particles remains unchanged, and the mass ratio is 8:1; other components, dosages, and process parameters are the same as in Embodiment 1.

[0084] Example 5

[0085] This embodiment provides a moisture-permeable membrane, which differs from Embodiment 1 only in that the total mass of the PVP base film and the hybrid particles remains unchanged, and the mass ratio is 25:1; other components, dosages, and process parameters are the same as in Embodiment 1.

[0086] Example 6

[0087] This embodiment provides a moisture-permeable membrane, which differs from Embodiment 1 only in that the total mass of the PVP base film and the hybrid particles remains unchanged, and the mass ratio is 1:1; other components, dosages, and process parameters are the same as in Embodiment 1.

[0088] Example 7

[0089] This embodiment provides a moisture-permeable membrane, which differs from Embodiment 1 only in that the content of gold nanoparticles in the hybrid particles is adjusted so that the mass ratio of PDMAEMA particles to gold nanoparticles is 5:1; other components, dosages, and process parameters are the same as in Embodiment 1.

[0090] Example 8

[0091] This embodiment provides a moisture-permeable membrane, which differs from Embodiment 1 only in that the content of gold nanoparticles in the hybrid particles is adjusted so that the mass ratio of PDMAEMA particles to gold nanoparticles is 25:1; other components, dosages, and process parameters are the same as in Embodiment 1.

[0092] Example 9

[0093] This embodiment provides a moisture-permeable membrane, which differs from Embodiment 1 only in that the average particle size of the hybrid particles is 320 nm; the other components, dosages, and process parameters are the same as in Embodiment 1.

[0094] Example 10

[0095] This embodiment provides a moisture-permeable membrane, which differs from Embodiment 1 only in that the average particle size of the hybrid particles is 100 nm; the other components, dosages, and process parameters are the same as in Embodiment 1.

[0096] Example 11

[0097] This embodiment provides a moisture-permeable membrane, which differs from Embodiment 3 only in that the average particle size of the gold nanoparticles is 20 nm, the length of the gold nanorods is 56 nm, the diameter is 15 nm, and the aspect ratio is 3.7; other components, dosages, and process parameters are the same as in Embodiment 3.

[0098] Example 12

[0099] This embodiment provides a moisture-permeable membrane, which differs from Embodiment 3 only in that the average particle size of the gold nanoparticles is 180 nm, the length of the gold nanorods is 150 nm, the diameter is 30 nm, and the aspect ratio is 5; other components, dosages, and process parameters are the same as in Embodiment 3.

[0100] Example 13

[0101] This embodiment provides a moisture-permeable membrane, which differs from Embodiment 1 only in that PDMAEMA particles are replaced with PNIPAM particles of equal mass and average particle size. Other components, dosages, and process parameters are the same as in Embodiment 1.

[0102] Comparative Example 1

[0103] This comparative example provides a moisture-permeable membrane, which differs from Example 1 only in that the hybrid particles do not contain gold nanomaterials, and in the preparation method, gold nanoparticles are not added in step (1). Other components, dosages, and process parameters are the same as in Example 1.

[0104] Comparative Example 2

[0105] This comparative example provides a breathable membrane, which differs from Example 1 only in that gold nanomaterials are coated on the surface of the PDMAEMA particles in the hybrid particles. The preparation method includes: in step (1), no gold nanoparticles are added, thus obtaining PDMAEMA particles; then, according to the formula amount, PDMAEMA particles, gold nanoparticles and deionized water are mixed at 60°C for 1 hour, and freeze-dried to obtain PDMAEMA particles with a gold nanolayer with a thickness of 75 nm on the surface; then, the obtained PDMAEMA particles with a gold nanolayer with a thickness of 75 nm are subjected to step (2), and other components, amounts and process parameters are the same as in Example 1.

[0106] Comparative Example 3

[0107] This comparative example provides a moisture-permeable membrane, which differs from Example 1 only in that the base membrane does not contain hybrid particles, while the other components, dosages, and process parameters are the same as in Example 1.

[0108] Performance testing

[0109] The performance of the moisture-permeable membranes provided in Examples 1-13 and Comparative Examples 1-3 was tested as follows.

[0110] (1) Water molecule transfer rate: Referring to standard GB / T 1037-2021, the water molecule transfer rate of the moisture permeable membrane was tested at 38℃ and 90% relative humidity before and after 30 minutes of continuous irradiation with near-infrared light (wavelength 780nm~1100nm); and the rate of change of water molecule transfer rate was calculated; wherein, the rate of change of water molecule transfer rate = (water molecule transfer rate after 30 minutes of irradiation - water molecule transfer rate before irradiation) / water molecule transfer rate before irradiation × 100%.

[0111] (2) Response time: Refer to standard GB / T 36363-2018, test the time (sec) for the membrane surface temperature to reach 50℃ under near-infrared light (wavelength 780nm~1100nm) irradiation at 38℃ and 90% relative humidity. The shorter the time to reach the required temperature, the faster the response speed.

[0112] The specific test results are shown in Table 1:

[0113] Table 1

[0114]

[0115]

[0116] As shown in Table 1, the moisture-permeable membrane provided by this invention, by adding hybrid particles formed by thermosensitive polymer particles and gold nanomaterials to the base membrane, can promote the transfer of water molecules, ensure good moisture permeability of the membrane, and help reduce the formation of condensate. Through the examples and comparative examples 1 and 3, it can be seen that the moisture-permeable membranes without the addition of at least one of the thermosensitive polymer particles and gold nanomaterials do not have the effect of accelerating the water molecule transfer rate before and after near-infrared light irradiation, and cannot accelerate the water molecule transfer rate under near-infrared light irradiation to obtain better moisture permeability. However, through the comparison of Example 1 and Comparative Example 2, it can be seen that under basically the same conditions, the hybrid particles formed by thermosensitive polymer particles and gold nanomaterials have a shorter response time and a higher water molecule transfer rate and a higher rate of change in water molecule transfer rate, ensuring better performance. Therefore, the moisture-permeable membrane can remove condensate from the membrane surface in a timely and rapid manner, ensuring the membrane's performance.

[0117] The applicant declares that the above description is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention fall within the protection and disclosure scope of the present invention.

Claims

1. A moisture permeable film, characterized by, The moisture-permeable membrane includes a base membrane and hybrid particles distributed within the base membrane; The hybrid particles include thermosensitive polymer particles and gold nanomaterials distributed within the thermosensitive polymer particles.

2. The moisture-permeable membrane according to claim 1, characterized in that, The mass ratio of the thermosensitive polymer particles to the gold nanomaterials is (8-20):

1.

3. The moisture-permeable membrane according to claim 1 or 2, characterized in that, The gold nanomaterials include at least one of one-dimensional gold nanomaterials and gold nanoparticles; Preferably, the aspect ratio of the one-dimensional gold nanomaterial is 5 to 20; Preferably, the length of the one-dimensional gold nanomaterial is 20 nm to 125 nm, and the diameter is 5 nm to 25 nm. Preferably, the average particle size of the gold nanoparticles is 50 nm to 150 nm.

4. The moisture-permeable membrane according to any one of claims 1 to 3, characterized in that, The thermosensitive polymer particles include amino thermosensitive polymer particles; Preferably, the temperature-sensitive polymer particles include at least one of N,N-dimethylaminoethyl methacrylate, poly[(N,N-diethylaminoethyl methacrylate)], and their derivatives.

5. The moisture-permeable membrane according to any one of claims 1 to 4, characterized in that, The average particle size of the hybrid particles is 200 nm to 300 nm.

6. The moisture-permeable membrane according to any one of claims 1 to 5, characterized in that, The mass ratio of the base film to the hybrid particles is (4-20):

1.

7. The moisture-permeable membrane according to any one of claims 1 to 6, characterized in that, The thickness of the moisture-permeable membrane is 0.5 μm to 2 μm.

8. A method for preparing a moisture-permeable membrane according to any one of claims 1 to 7, characterized in that, The preparation method includes the following steps: The raw materials of the base membrane are mixed with hybrid particles to form a membrane, thus obtaining the moisture-permeable membrane; Preferably, the raw material of the base film includes a polymer, wherein the weight-average molecular weight of the polymer is 40 kDa to 100 kDa.

9. The preparation method according to claim 8, characterized in that, The method for preparing the hybrid particles includes: A thermosensitive polymer, gold nanomaterials, and solvent are mixed to prepare a hybrid particle dispersion. The hybrid particle dispersion is then dried to obtain the hybrid particles.

10. The application of a moisture-permeable membrane as described in any one of claims 1 to 7 in a food preservation film or a total heat exchange membrane.

Images