Hydrogen-sensitive adhesive composition and hydrogen-sensitive functional film as well as preparation method and application of hydrogen-sensitive adhesive composition and hydrogen-sensitive functional film

Abstract

The invention relates to the technical field of gas-sensitive sensing, and discloses a hydrogen-sensitive adhesive composition and a hydrogen-sensitive functional film as well as a preparation method and application of the hydrogen-sensitive adhesive composition and the hydrogen-sensitive functional film. The hydrogen-sensitive functional film comprises a transparent substrate layer and a hydrogen-sensitive color-changing layer located on one surface of the transparent substrate layer, the hydrogen-sensitive adhesive composition contains a hydrogen-induced color-changing material, polyacrylate, an initiator and an anionic emulsifier, the hydrogen-induced color-changing material comprises hexagonal-phase tungsten trioxide and precious metal nanoparticles, and the polyacrylate is an anionic emulsifier. The hexagonal-phase tungsten trioxide has a microstructure of a nanorod bundle formed by stacking a plurality of nanorods, and the dispersity of the noble metal nanoparticles on the hexagonal-phase tungsten trioxide is greater than or equal to 70%; the particle size of the hydrogen-induced discoloration material is 100 [mu] m or less. The hydrogen-sensitive functional film provided by the invention has quick response capability to hydrogen and has better environmental adaptability.

Description

Technical Field

[0001] The present invention relates to the field of gas-sensitive sensing technology, and in particular to a hydrogen-sensitive adhesive composition and a hydrogen-sensitive functional film, and a preparation method and application thereof. Background Art

[0002] The development of renewable energy represented by hydrogen energy is of great significance for my country to build a modern energy system that is "clean, low-carbon, safe and efficient". Hydrogen leak detection technology is the key to ensuring the safe development of the hydrogen energy industry.

[0003] The transportation sector based on fuel cell vehicles and hydrogen refueling stations is an important breakthrough for the recent development of the hydrogen energy industry. However, a hydrogen explosion occurred at a hydrogen refueling station. The accident investigation results showed that the direct cause of the accident was the lack of effective detection of hydrogen leakage. The accident led to regulatory measures such as the ban on hydrogen refueling stations and the ban on the sale of fuel cell vehicles across Norway, which aroused people's concerns about the safe development of the hydrogen energy industry.

[0004] Hydrogen has the characteristics of small molecules and easy penetration of materials to leak. At the same time, hydrogen is colorless and it is difficult for humans to effectively detect leakage. Therefore, the main technical challenge faced by hydrogen refueling stations in daily operation is how to achieve effective detection of hydrogen leaks. According to on-site investigations, hydrogen refueling stations mainly use fixed electrical hydrogen sensors to solve this problem. However, due to the large number of hydrogen pipelines and equipment connection points in hydrogen refueling stations, and the rapid diffusion rate of hydrogen, fixed electrical hydrogen sensors are difficult to effectively detect hydrogen leaks, let alone accurately locate the hydrogen leak site. Optical hydrogen leak detection technology based on hydrogen color-changing mechanism provides a feasible way to solve the above problems. The main challenge faced by the application of optical hydrogen leak detection technology is how to prepare inorganic functional materials with hydrogen color-changing properties into flexible materials that can be installed and used in hydrogen refueling stations, so as to achieve rapid detection and accurate positioning of hydrogen leaks.

[0005] Patent application CN113155906A discloses a hydrogen sensor and a preparation method and a hydrogen detection method, including a substrate, a hydrogen-sensitive film arranged under the substrate, and a gas-selective film arranged on the side of the hydrogen-sensitive film away from the substrate. The hydrogen-sensitive film used is selected from one of palladium nanofilm, magnesium nanofilm, yttrium nanofilm and nickel-magnesium alloy nanofilm, or a laminate formed by at least two of them. The preparation process of the hydrogen sensor is relatively complicated, involving the preparation of an elastic substrate, a substrate for a magnetron sputtering hydrogen-sensitive film, a spin coating method for preparing a polyacrylic acid film and a polymethyl methacrylate film, and a composite between films. There are many steps, and the reaction time for 4% hydrogenation is about 7s, which still makes it difficult to quickly detect hydrogen leaks.

[0006] Patent application CN113720780A discloses a hydrogen-sensitive optical element and a hydrogen-sensitive optical sensor, wherein the hydrogen-sensitive optical element includes a light-transmitting substrate and a hydrogen-sensitive film attached to at least one surface of the light-transmitting substrate, wherein Ag@Pd core-shell nanoparticles are distributed in the hydrogen-sensitive film, and the Ag@Pd core-shell nanoparticles are Ag cores wrapped with Pd shells, thereby realizing optical detection of hydrogen leakage. However, the response time to different concentrations of hydrogen is not specified.

[0007] Patent application CN109825090B discloses a hydrogen-sensitive composite silica gel material and a preparation method thereof, wherein a compound of vinyl silicone rubber, methyl MQ silicone resin, zinc oxide and silicon dioxide is dried, and then molybdenum oxide, palladium catalyst, hydroxy silicone oil and hydrogen-containing silicone oil are added for refining and drying. Molybdenum oxide and palladium catalyst are used as hydrogen-sensitive materials, and the palladium content is relatively high, accounting for 0.5-2wt.% of the hydrogen-sensitive composite silica gel material. The color change time is relatively long, at 49-72s, which poses certain challenges for the rapid detection of hydrogen leaks.

[0008] Patent application CN111662650A discloses a hydrogen-sensitive color-changing detection tape and its preparation method and application, which comprises polysiloxane, reinforcing agent, cross-linking agent, cross-linking catalyst, metal oxide, metal nanoparticles, etc. The raw materials are mixed on a kneader and then extruded through an extruder. Among them, the polysiloxane used is hydroxyl-terminated polysiloxane with a molecular weight of 400,000-600,000. For a 1L / min hydrogen mixture, when the hydrogen concentration is 1vol.%, there is a color change response in 3-10min, and when the hydrogen concentration is 4vol.%, there is a color change response in 1-3min. Summary of the invention

[0009] In view of the fact that existing high-pressure hydrogen equipment such as hydrogen refueling stations and hydrogen supply stations have many connection parts but lack effective hydrogen leakage detection methods for rapid detection and accurate positioning, the present invention provides a hydrogen-sensitive adhesive composition and a hydrogen-sensitive functional film and a preparation method and application thereof. The hydrogen-sensitive functional film not only has a rapid response capability to hydrogen, but also has a high color contrast before and after color change, which is convenient for rapid and accurate detection of hydrogen leakage.

[0010] In order to achieve the above-mentioned object, the present invention provides a hydrogen-sensitive adhesive composition on the one hand, which contains a hydrogen-chromic material, a polyacrylate, an initiator and an anionic emulsifier, wherein the hydrogen-chromic material comprises hexagonal tungsten trioxide and precious metal nanoparticles, the hexagonal tungsten trioxide has a microstructure of nanorod bundles formed by the accumulation of multiple bundles of nanorods, and the dispersion of the precious metal nanoparticles on the hexagonal tungsten trioxide is ≥70%, preferably ≥75%, and more preferably ≥80%; the particle size of the hydrogen-chromic material is less than 100 μm, preferably 1-60 μm.

[0011] Preferably, relative to 100 parts by weight of the polyacrylate, the content of the hydrogenochromic material is 1-10 parts by weight, preferably 3-7 parts by weight; the content of the initiator is 0.1-2 parts by weight, preferably 0.2-1.2 parts by weight; the content of the anionic emulsifier is 1-10 parts by weight, preferably 2.5-5 parts by weight.

[0012] Preferably, in the hydrogenochromic material, based on the total weight of the hydrogenochromic material, the content of the hexagonal tungsten trioxide is 98.5-99.9% by weight, and the content of the noble metal nanoparticles is 0.1-1.5% by weight.

[0013] Preferably, the noble metal nanoparticles are at least one of platinum nanoparticles, palladium nanoparticles, rhodium nanoparticles and gold nanoparticles, more preferably platinum nanoparticles.

[0014] Preferably, the average size of the noble metal nanoparticles is ≤5 nm, preferably ≤2 nm.

[0015] Preferably, the initial reduction temperature of the hydrogen-induced chromic material to hydrogen is ≤100°C, preferably ≤80°C, more preferably ≤60°C.

[0016] Preferably, the polyacrylate is a polymer formed by polymerized monomers, and the polymerized monomers are selected from at least one of acrylic acid, ethyl acrylate, propyl acrylate, isopropyl acrylate, n-butyl acrylate, tert-butyl acrylate, isobutyl acrylate, isooctyl acrylate, hydroxyethyl acrylate and 2-methoxyethyl acrylate.

[0017] Preferably, the polymerizable monomers are selected from at least two of acrylic acid, n-butyl acrylate, isooctyl acrylate, hydroxyethyl acrylate and 2-methoxyethyl acrylate.

[0018] Preferably, the initiator is at least one of azobisisobutyronitrile, dibenzoyl peroxide and tert-butyl perbenzoate.

[0019] Preferably, the anionic emulsifier is selected from one or any combination of two or more of alkyl sodium sulfate, alkyl sodium benzene sulfonate, dialkyl sodium 2-sulfosuccinate and alkyl allyloxy polyoxyethylene sodium phosphate.

[0020] Preferably, the hydrogen-sensitive adhesive composition further contains an anti-ultraviolet additive.

[0021] Preferably, the content of the anti-ultraviolet auxiliary agent is 3-30 parts by weight, preferably 6-26 parts by weight, relative to 100 parts by weight of the polyacrylate.

[0022] Preferably, the anti-ultraviolet auxiliary agent is nano titanium dioxide.

[0023] Preferably, the particle size of the nano titanium dioxide is 1-100 nm.

[0024] The second aspect of the present invention provides a hydrogen-sensitive functional film, which includes a transparent substrate layer and a hydrogen-sensitive color-changing layer located on one surface of the transparent substrate layer, wherein the hydrogen-sensitive color-changing layer is the hydrogen-sensitive adhesive composition described above.

[0025] Preferably, the thickness of the hydrogen-sensitive color-changing layer is 1-60 μm, preferably 3-40 μm.

[0026] Preferably, the amount of hydrogen-induced color changing material is 0.5-40g / m 2 , preferably 1.5-25g / m 2 .

[0027] Preferably, the transparent substrate layer is a polyethylene terephthalate film and / or a polyethylene film.

[0028] Preferably, the thickness of the transparent substrate layer is 5-200 μm, more preferably 10-150 μm.

[0029] Preferably, the light transmittance of the transparent substrate layer is greater than 90%.

[0030] Preferably, the color change response time to a hydrogen concentration of 4 volume % is less than 3 seconds, and the color change response time to a hydrogen concentration of 10 volume % is less than 1 second.

[0031] Preferably, the hydrogen-sensitive functional film further comprises a release layer covering the hydrogen-sensitive color-changing layer.

[0032] The third aspect of the present invention provides a method for preparing a hydrogen-sensitive functional membrane, the method comprising the following steps:

[0033] (1) grinding the hydrochromic material to obtain a hydrochromic material powder having a particle size of less than 100 μm;

[0034] (2) mixing the hydrochromic material powder, anionic emulsifier and optional anti-ultraviolet auxiliary agent, and emulsifying to obtain an emulsion;

[0035] (3) mixing the emulsion obtained in step (2), a polymerization monomer and an initiator to obtain a hydrogen-sensitive adhesive composition;

[0036] (4) coating a non-silicon release agent on one surface of the transparent substrate layer, and then coating the hydrogen-sensitive adhesive composition obtained in step (3) on the non-silicon release agent to form a hydrogen-sensitive color-changing layer;

[0037] (5) Optionally, a release layer is covered on the hydrogen-sensitive color-changing layer;

[0038] The hydrogen-induced color-changing material comprises hexagonal tungsten trioxide and noble metal nanoparticles, the hexagonal tungsten trioxide has a microstructure of nanorod bundles formed by stacking multiple bundles of nanorods, and the dispersion of the noble metal nanoparticles on the hexagonal tungsten trioxide is ≥70%, preferably ≥75%, and more preferably ≥80%;

[0039] The polymerizable monomer described in step (3) is selected from at least one of acrylic acid, ethyl acrylate, propyl acrylate, isopropyl acrylate, n-butyl acrylate, tert-butyl acrylate, isobutyl acrylate, isooctyl acrylate, hydroxyethyl acrylate and 2-methoxyethyl acrylate.

[0040] Preferably, in step (1), the hydrochromic material powder is ground to obtain a particle size of 2-60 μm.

[0041] Preferably, in step (2), the emulsification temperature is 40-95°C, preferably 55-85°C.

[0042] Preferably, in step (3), the mixing reaction is carried out under high-speed stirring, and the conditions of the mixing reaction include: temperature of 30-60° C., time of 0.5-5 h, and stirring speed of 200-1000 r / min.

[0043] A fourth aspect of the present invention provides use of the hydrogen-sensitive functional membrane described above or the hydrogen-sensitive functional membrane prepared according to the method described above in hydrogen leakage detection.

[0044] According to the technical scheme of the present invention, by combining hydrogen-induced color-changing materials, polyacrylates, initiators and anionic emulsifiers, and adjusting the particle size of the hydrogen-induced color-changing materials to a certain range, the hydrogen-sensitive adhesive composition not only has a rapid response capability to hydrogen, but also has a high color contrast before and after the color change, which is convenient for rapid and accurate detection of hydrogen leakage; moreover, in the preparation process of the hydrogen-sensitive functional film, the hexagonal tungsten trioxide and the precious metal nanoparticles in the hydrogen-induced color-changing materials are added as a whole, avoiding the defect of adding the two separately to the adhesive so that the two components cannot effectively contact, resulting in a long color change time; in addition, in the hydrogen-sensitive functional film of the present invention, the hydrogen-induced color-changing materials in the hydrogen-sensitive color-changing layer directly contact with hydrogen during detection, avoiding the defect of prolonged color change time caused by hydrogen penetrating the material. Specifically, the hydrogen-sensitive functional film of the present invention has a color change response time of <3s to 4% hydrogen and a color change response time of <1s to 10% hydrogen, which greatly reduces the color change response time.

[0045] Moreover, the dosage of the noble metal nanoparticles in the hydrogen-sensitive functional film of the present invention is relatively low, which can effectively reduce the product cost and facilitate large-scale application.

[0046] In addition, the hydrogen-sensitive functional film of the present invention only has the color-changing response characteristic to the hydrogen-presence equipment that the hydrogen-sensitive color-changing film contacts, and the external interfering gas (including hydrogen) cannot penetrate the transparent base layer to cause it to change color. Therefore, the hydrogen-sensitive functional film has high selectivity and high environmental adaptability, and provides an effective, reliable, highly selective and highly environmentally adaptable technical solution for hydrogen leak detection. DETAILED DESCRIPTION

[0047] The specific embodiments of the present invention are described in detail below. It should be understood that the specific embodiments described herein are only used to illustrate and explain the present invention, and are not used to limit the present invention.

[0048] The endpoints and any values ​​of the ranges disclosed in this article are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of each range, the endpoint values ​​of each range and the individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed in this article.

[0049] The hydrogen-sensitive adhesive composition of the invention contains a hydrogen-induced color-changing material, polyacrylate, an initiator and an anionic emulsifier.

[0050] In the hydrogen-sensitive adhesive composition, relative to 100 parts by weight of the polyacrylate, the content of the hydrogenochromic material may be 1-10 parts by weight, preferably 3-7 parts by weight; the content of the initiator may be 0.1-2 parts by weight, preferably 0.2-1.2 parts by weight; the content of the anionic emulsifier may be 1-10 parts by weight, preferably 2.5-5 parts by weight.

[0051] In a preferred case, the polyacrylate is a polymer formed by polymerized monomers, and the polymerized monomers are selected from at least one of acrylic acid, ethyl acrylate, propyl acrylate, isopropyl acrylate, n-butyl acrylate, tert-butyl acrylate, isobutyl acrylate, isooctyl acrylate, hydroxyethyl acrylate and 2-methoxyethyl acrylate. Further preferably, the polymerized monomers are selected from at least two of acrylic acid, n-butyl acrylate, isooctyl acrylate, hydroxyethyl acrylate and 2-methoxyethyl acrylate.

[0052] In some embodiments, the polymerizable monomer is a combination of n-butyl acrylate, acrylic acid and isooctyl acrylate. According to this embodiment, in the polymerizable monomer, the mass ratio of n-butyl acrylate, acrylic acid and isooctyl acrylate is (1-5): (1-3): 1, preferably (2-4): (1.5-2.5): 1, and most preferably 3:2:1.

[0053] In other embodiments, the polymerizable monomer is a combination of n-butyl acrylate, isooctyl acrylate and hydroxyethyl acrylate. According to this embodiment, in the polymerizable monomer, the mass ratio of n-butyl acrylate, isooctyl acrylate and hydroxyethyl acrylate is (1-3): (0.5-2): 1, preferably (1.5-2.5): (0.8-1.4): 1, and most preferably 2: 1: 1.

[0054] In other embodiments, the polymerizable monomer is a combination of 2-methoxyethyl acrylate, isooctyl acrylate and hydroxyethyl acrylate. According to this embodiment, in the polymerizable monomer, the mass ratio of 2-methoxyethyl acrylate, isooctyl acrylate and hydroxyethyl acrylate is (2-6): (1-3): 1, preferably (3-5): (1.5-2.5): 1, and most preferably 4:2:1.

[0055] In other embodiments, the polymerizable monomer is a combination of n-butyl acrylate and hydroxyethyl acrylate. According to this embodiment, in the polymerizable monomer, the mass ratio of n-butyl acrylate to hydroxyethyl acrylate is (2-6):1, preferably (3-5):1, and most preferably 4:1.

[0056] In other embodiments, the polymerizable monomer is a combination of 2-methoxyethyl acrylate and hydroxyethyl acrylate. According to this embodiment, in the polymerizable monomer, the mass ratio of 2-methoxyethyl acrylate to hydroxyethyl acrylate is (2-6):1, preferably (3-5):1.

[0057] In the hydrogen-sensitive adhesive composition, preferably, the initiator is at least one of azobisisobutyronitrile, dibenzoyl peroxide and tert-butyl perbenzoate.

[0058] In the hydrogen-sensitive adhesive composition, preferably, the anionic emulsifier is selected from one or any combination of two or more of alkyl sodium sulfate, sodium alkylbenzene sulfonate, dialkyl-2-sulfosuccinate and alkyl allyloxy polyoxyethylene sodium phosphate. The alkyl sodium sulfate may be, for example, sodium n-dodecyl sulfate. The alkyl sodium benzene sulfonate may be, for example, sodium n-dodecylbenzene sulfonate.

[0059] In the present invention, preferably, the hydrogen-sensitive adhesive composition further contains an anti-ultraviolet additive, so as to improve the environmental adaptability of the hydrogen-sensitive adhesive composition.

[0060] Further preferably, in the hydrogen-sensitive adhesive composition, the content of the anti-ultraviolet auxiliary agent is 3-30 parts by weight, preferably 6-26 parts by weight, relative to 100 parts by weight of the polyacrylate.

[0061] In the present invention, the anti-ultraviolet auxiliary agent is preferably nano titanium dioxide. The particle size of the nano titanium dioxide can be 1-100nm. In this article, "particle size" refers to the maximum straight-line distance between two different points on the particle. When the particle is spherical, the particle size refers to the diameter of the particle.

[0062] In the hydrogen-sensitive adhesive composition of the present invention, the hydrogen-induced color-changing material comprises hexagonal tungsten trioxide and precious metal nanoparticles, the hexagonal tungsten trioxide has a microstructure of nanorod bundles formed by stacking multiple bundles of nanorods, and the dispersion degree of the precious metal nanoparticles on the hexagonal tungsten trioxide is ≥70%, preferably ≥75%, and more preferably ≥80%.

[0063] In the present invention, the dispersion degree refers to the dispersion performance of the noble metal nanoparticles on the hexagonal tungsten trioxide, which is tested by a quantitative hydrogen pulse chemical reaction method.

[0064] In the hydrogen-sensitive adhesive composition of the present invention, the particle size of the hydrogen-induced chromic material is less than 100 μm, preferably 1-60 μm.

[0065] In the hydrogenochromic material, based on the total weight of the hydrogenochromic material, the content of the hexagonal tungsten trioxide can be 98.5-99.9% by weight, preferably 98.8-99.5% by weight, and more preferably 98.9-99.3% by weight; the content of the noble metal nanoparticles can be 0.1-1.5% by weight, preferably 0.5-1.2% by weight, and more preferably 0.7-1.1% by weight.

[0066] In the present invention, the content of the noble metal nanoparticles is detected by an X-ray fluorescence method.

[0067] In the hydrogenochromic material, the diameter of the nanorod is 1-10 nm, the length of the nanorod bundle is between 500-1000 nm, and the diameter is between 50-100 nm. Further preferably, the nanorod bundle contains no less than 20 nanorods, and the aspect ratio of the nanorod bundle is preferably 5-20.

[0068] In the present invention, the microstructure of the hexagonal tungsten trioxide is obtained by scanning electron microscopy and high-power transmission electron microscopy analysis and observation.

[0069] In the present invention, the hexagonal tungsten trioxide has (002), (100), and (001) as the main exposed crystal planes, and the XRD characteristic diffraction peak intensity meets the following conditions: (002) =0.9-1.1×I (100) , and I (002) =1.2-2×I (001) , where I(002) is the intensity of the characteristic diffraction peak of the (002) crystal plane, I (100) is the intensity of the characteristic diffraction peak of the (100) crystal plane, I (001) is the intensity of the (001) crystal plane diffraction peak.

[0070] In the present invention, unless otherwise specified, the XRD diffraction pattern is obtained by X-ray diffractometer testing.

[0071] In the present invention, when the reflectivity of barium sulfate is equal to 100% as the standard, the reflectivity of the hexagonal tungsten trioxide to visible light in the wavelength range of 400-750nm measured by a spectrometer is ≥50%, preferably ≥60%, and more preferably ≥65%. For example, among the reflectivities of a certain hexagonal tungsten trioxide to light of all wavelengths in the wavelength range of 400-750nm, the reflectivity of light at a wavelength of 400nm is the lowest, which is 50%, and the reflectivity of light at a wavelength of 700nm is the highest, which is 70%. Then the reflectivity range of the hexagonal tungsten trioxide to visible light in the wavelength range of 400-750nm is 50-70%.

[0072] It should be noted that the value greater than or equal to the reflectivity of light within a certain wavelength range refers to the lowest value among the reflectivity of light of all wavelengths within the wavelength range. For example, among the reflectivity of light of all wavelengths within the wavelength range of 400-750nm, the reflectivity of light at 400nm is the lowest, which is 50%. Then the reflectivity of the hexagonal tungsten trioxide to visible light within the wavelength range of 400-750nm is ≥50%. Similarly, the value less than or equal to the reflectivity of light within a certain wavelength range refers to the highest value among the reflectivity of light of all wavelengths within the wavelength range.

[0073] In the present invention, when the reflectivity of barium sulfate is equal to 100% as a standard, the reflectivity of the hexagonal tungsten trioxide measured by a spectrometer to blue light within a wavelength range of 400-500nm is ≥50%, and the reflectivity of the red light within a wavelength range of 600-750nm is ≥70%. Preferably, when the reflectivity of barium sulfate is equal to 100% as a standard, the reflectivity of the hexagonal tungsten trioxide measured by a spectrometer to blue light within a wavelength range of 400-500nm is ≥67%, and the reflectivity of the red light within a wavelength range of 600-750nm is ≥72%.

[0074] In the present invention, unless otherwise specified, the reflectivity is obtained by testing with a spectrometer, with the reflectivity of barium sulfate being 100% as the standard. In the present invention, unless otherwise specified, the "visible light" refers to light in the wavelength range of 400-750nm; the "blue light" refers to light in the wavelength range of 400-500nm; and the "red light" refers to light in the wavelength range of 600-750nm.

[0075] In the present invention, the reflectivity refers to the percentage of the reflected luminous flux of visible light to the incident luminous flux. There is a corresponding relationship between reflectivity and color and its depth. The higher the reflectivity of visible light, the lighter the color; the higher the reflectivity of light in a certain wavelength range, the higher the proportion of the corresponding color in the observed color within the wavelength range. In the present invention, the "blue" refers to a reflectivity of 30-37% for blue light in the wavelength range of 400-500nm, and a reflectivity of 20-30% for red light in the wavelength range of 600-750nm. In the present invention, the "dark blue" refers to a reflectivity of 15-29% for light in the wavelength range of 400-500nm, and a reflectivity of 1-15% for red light in the wavelength range of 600-750nm.

[0076] In the present invention, the noble metal nanoparticles may be one or more of platinum nanoparticles, palladium nanoparticles, rhodium nanoparticles and gold nanoparticles, preferably platinum nanoparticles.

[0077] In the present invention, the average size of the noble metal nanoparticles is ≤5 nm, more preferably ≤2 nm.

[0078] In the present invention, the average size of the noble metal nanoparticles is obtained by high resolution transmission electron microscopy (HRTEM) combined with energy dispersive spectrometer (ESD) analysis.

[0079] In the present invention, the initial reduction temperature of the hydrogen chromic material to hydrogen is ≤100°C, preferably ≤80°C, and more preferably ≤60°C. In a specific embodiment, the initial reduction temperature of the hydrogen chromic material to hydrogen can be 60°C, 55°C, 50°C, 45°C, 40°C, 35°C, 30°C, 25°C, 20°C, 15°C or 10°C. In a further preferred case, the initial reduction temperature of the hydrogen chromic material to hydrogen is ≤50°C, and more preferably ≤43°C.

[0080] In the present invention, "the initial reduction temperature to hydrogen" refers to the initial temperature when an obvious hydrogen consumption peak appears in the TPR analysis, which is obtained by a chemical adsorption instrument. The lower the initial reduction temperature to hydrogen, the better the reduction performance of the hydrogen-induced chromic material.

[0081] In the present invention, when the reflectivity of barium sulfate is 100% as a standard, the reflectivity of the hydrogenochromic material to visible light within the wavelength range of 400-750 nm measured by a spectrometer is ≥40%, preferably ≥45%.

[0082] In the present invention, when the reflectivity of barium sulfate is 100% as the standard, the reflectivity of the hydrogenochromic material measured by a spectrometer to blue light within the wavelength range of 400-500nm is ≥45%, and the reflectivity to red light within the wavelength range of 600-750nm is ≥49%.

[0083] In the present invention, when the reflectivity of barium sulfate is equal to 100% as a standard, the reflectivity of the hydrogen-induced chromic material to visible light within the wavelength range of 400-750nm measured by a spectrometer is ≤30%.

[0084] In the present invention, when the reflectivity of barium sulfate is 100% as the standard, the reflectivity of the hydrogenochromic material measured by a spectrometer to blue light within the wavelength range of 400-500nm is ≤30%, and the reflectivity of red light within the wavelength range of 600-750nm is ≤20%.

[0085] The method for measuring the reflectivity of the hydrogen-induced chromic material of the present invention is as follows: a sample groove with a diameter of 2 cm and a thickness of 1 cm is placed in a closed gas chamber (diameter of 10 cm and thickness of 5 cm), the hydrogen-induced chromic material is placed in the sample groove and ground flat, and then hydrogen with a concentration of 10 volume % is introduced at room temperature to contact the hydrogen-induced chromic material for 60 seconds to obtain a test sample, and a spectrometer is used to perform real-time testing on the color change process to obtain reflectivity data of the test sample.

[0086] In the present invention, the reflectivity change difference of the hydrogen chromic material to visible light within the wavelength range of 400-750nm is ≥20%.

[0087] In the present invention, the reflectivity change difference of the hydrogen-induced chromic material to blue light in the wavelength range of 400-500nm is ≥22%, and the reflectivity change difference to red light in the wavelength range of 600-750nm is ≥30%.

[0088] In the present invention, the reflectivity change difference refers to the difference between the reflectivity of the hydrogen-chromic material before and after hydrogenation. Specifically, the difference between the reflectivity of the hydrogen-chromic material before and after hydrogenation refers to the difference between the reflectivity of the hydrogen-chromic material to light of the same wavelength before and after hydrogenation. It should be noted that the minimum value of the reflectivity change difference of the hydrogen-chromic material to light within a certain wavelength range refers to the minimum value of the reflectivity difference of the hydrogen-chromic material to light within the wavelength range before and after hydrogenation. For example, before hydrogen is passed through a certain hydrogenochromic material, the reflectivity of blue light within the wavelength range of 400-500nm is between 50-60%, wherein the reflectivity of light at a wavelength of 450nm is 55%; after hydrogen is passed through, the reflectivity of blue light within the wavelength range of 400-500nm is between 20-30%, wherein the reflectivity of light at a wavelength of 450nm is 30%, then the reflectivity change difference of the hydrogenochromic material to light with a wavelength of 450nm is 25%; if the reflectivity change difference of the material to light with a wavelength of 450nm is lower than the reflectivity change difference of the material to light with other wavelengths within the wavelength range of 400-500nm, then the reflectivity of the hydrogenochromic material to blue light within the wavelength range of 400-500nm is ≥25%.

[0089] In the present invention, the color change response time of the hydrogen-induced color-changing material to pure hydrogen is ≤2s, the color change response time to hydrogen with a concentration of 10 volume % is ≤5s, the color change response time to hydrogen with a concentration of 4 volume % is ≤10s, the color change response time to hydrogen with a concentration of 2 volume % is ≤13s, the color change response time to hydrogen with a concentration of 1 volume % is ≤15s, the color change response time to hydrogen with a concentration of 0.5 volume % is ≤25s, and the color change response time to hydrogen with a concentration of 0.1 volume % is ≤50s. Wherein, the detection conditions of the above color change response time are: at room temperature, the flow rate of hydrogen is 200mL / min.

[0090] In the present invention, the "color change response time" refers to the time required for the color of the hydrogen-induced color material to undergo a significant visible change after hydrogen is passed through it, corresponding to the time required for the reflectivity change difference of light at a wavelength of 700nm to reach 10%.

[0091] In the present invention, the method for determining the color change response time of the hydrogen-induced chromic material is as follows: a sample groove with a diameter of 2 cm and a thickness of 1 cm is placed in a closed gas chamber (diameter of 10 cm, thickness of 5 cm), the hydrogen-induced chromic material is placed in the sample groove and ground flat, hydrogen under specific conditions is introduced, and a spectrometer is used to conduct a real-time test on the color change process, that is, the reflectance spectrum data of the hydrogen-induced chromic material before and during the hydrogen flow is recorded in real time, and then the color change response time is obtained accordingly, that is, the time required for the reflectivity change difference of the hydrogen-induced chromic material to light at a wavelength of 700 nm to reach 10%.

[0092] In the present invention, the hydrogen-induced color-changing material has a color-changing response time of ≤2.5s to a hydrogen gas with a flow rate of 500mL / min at room temperature, a color-changing response time of ≤3s to a hydrogen gas with a flow rate of 400mL / min, a color-changing response time of ≤4s to a hydrogen gas with a flow rate of 300mL / min, a color-changing response time of ≤5s to a hydrogen gas with a flow rate of 200mL / min, a color-changing response time of ≤8s to a hydrogen gas with a flow rate of 100mL / min, a color-changing response time of ≤10s to a hydrogen gas with a flow rate of 50mL / min, and a color-changing response time of ≤20s to a hydrogen gas with a flow rate of 20mL / min. The detection condition of the above-mentioned response color-changing time is: at room temperature, the concentration of hydrogen is 10% by volume.

[0093] In the present invention, the color change response time of the hydrogen-induced color-changing material to hydrogen at -25°C with a concentration of 10% by volume is ≤27s, the color change response time to hydrogen at -15°C is ≤15s, the color change response time to hydrogen at -5°C is ≤13s, the color change response time to hydrogen at 5°C is ≤8s, the color change response time to hydrogen at 15°C is ≤6.5s, the color change response time to hydrogen at 25°C is ≤5s, the color change response time to hydrogen at 35°C is ≤4s, and the color change response time to hydrogen at 45°C is ≤3s. Wherein, the detection conditions of the above color change response time are: the flow rate of hydrogen is 200mL / min, and the concentration of hydrogen is 10% by volume.

[0094] In the present invention, the specific composition and related parameters of the hydrogen chromic material and the preparation method of the hydrogen chromic material refer to patent application CN115711713A.

[0095] The hydrogen-sensitive functional film of the present invention comprises a transparent base layer and a hydrogen-sensitive color-changing layer located on one surface of the transparent base layer, wherein the hydrogen-sensitive color-changing layer is the hydrogen-sensitive adhesive composition described above.

[0096] In the hydrogen-sensitive functional film of the present invention, the thickness of the hydrogen-sensitive color-changing layer may be 1-60 μm, preferably 3-40 μm.

[0097] In the hydrogen-sensitive functional film of the present invention, the amount of hydrogen-induced color-changing material can be 0.5-40g / m 2 , preferably 1.5-25g / m 2 .

[0098] In the hydrogen-sensitive functional film of the present invention, the transparent substrate layer is preferably a polyethylene terephthalate film and / or a polyethylene film.

[0099] In the hydrogen-sensitive functional film of the present invention, the light transmittance of the transparent substrate layer is greater than 90%, preferably greater than or equal to 93%.

[0100] In the hydrogen-sensitive functional film of the present invention, the thickness of the transparent substrate layer may be 5-200 μm, preferably 10-150 μm.

[0101] In the present invention, the hydrogen-sensitive functional film has the characteristic of rapid response to hydrogen. Specifically, the color change response time to hydrogen with a concentration of 4 volume % is less than 3 seconds, and the color change response time to hydrogen with a concentration of 10 volume % is less than 1 second.

[0102] In a preferred embodiment, the hydrogen-sensitive functional film further comprises a release layer covering the hydrogen-sensitive color-changing layer. The release layer is preferably made of PET, PE, etc., which is treated with fluorine on the surface. Preferably, the release force of the release layer is <10g / 25mm.

[0103] The method for preparing the hydrogen-sensitive functional membrane of the present invention comprises the following steps:

[0104] (1) grinding the hydrochromic material to obtain hydrochromic material powder;

[0105] (2) mixing the hydrochromic material powder, anionic emulsifier and optional anti-ultraviolet auxiliary agent, and emulsifying to obtain an emulsion;

[0106] (3) mixing the emulsion obtained in step (2), a polymerization monomer and an initiator to obtain a hydrogen-sensitive adhesive composition;

[0107] (4) coating a non-silicon release agent on one surface of the transparent substrate layer, and then coating the hydrogen-sensitive adhesive composition obtained in step (3) on the non-silicon release agent to form a hydrogen-sensitive color-changing layer;

[0108] (5) Optionally, a release layer is covered on the hydrogen-sensitive color-changing layer.

[0109] In the method of the present invention, the hydrogen-induced chromic material, the anionic emulsifier, the initiator, the polymerizable monomer and the anti-ultraviolet auxiliary agent are the same as those described above.

[0110] In the method of the present invention, under preferred circumstances, the amounts of the hydrogenochromic material, the anionic emulsifier, the initiator, the polymerizable monomer and the anti-ultraviolet aid are such that in the prepared hydrogen-sensitive adhesive composition, relative to 100 parts by weight of polyacrylate, the content of the hydrogenochromic material is 1-10 parts by weight, preferably 3-7 parts by weight; the content of the initiator is 0.1-2 parts by weight, preferably 0.2-1.2 parts by weight; the content of the anionic emulsifier is 1-10 parts by weight, preferably 2.5-5 parts by weight; the content of the anti-ultraviolet aid is 3-30 parts by weight, preferably 6-26 parts by weight.

[0111] In the method of the present invention, in step (1), the hydrochromic material powder is ground to obtain a particle size of less than 100 μm, preferably 1-60 μm.

[0112] In the method of the present invention, in step (2), the emulsification temperature can be 40-95°C, preferably 55-85°C.

[0113] In the method of the present invention, in step (3), the mixing reaction is preferably carried out under high-speed stirring, and the conditions of the mixing reaction may include: temperature of 30-60°C, time of 0.5-5h, and stirring speed of 200-1000r / min.

[0114] In the method of the present invention, in step (4), the non-silicone release agent may be polyethyleneimine, and its average molecular weight Mw may be 300-1200.

[0115] In the method of the present invention, in step (4), the amount of the hydrogen-sensitive adhesive composition is such that the thickness of the formed hydrogen-sensitive color-changing layer is 1-60 μm, preferably 3-40 μm.

[0116] In the method of the present invention, the material and thickness of the transparent base layer and the release layer are the same as those described above.

[0117] The present invention also provides the use of the above hydrogen-sensitive functional membrane in hydrogen leakage detection. In the process of hydrogen leakage detection using the hydrogen-sensitive functional membrane of the present invention, it not only has a rapid response capability to hydrogen (the color change response time for 4% hydrogen is less than 3s, and the color change response time for 10% hydrogen is less than 1s), but also has a high color contrast before and after the color change, which is convenient for rapid and accurate detection of hydrogen leakage. Moreover, during detection, the hydrogen-induced color-changing material in the hydrogen-sensitive color-changing layer is in direct contact with hydrogen, avoiding the defect of prolonged color change time caused by hydrogen penetrating the material.

[0118] The hydrogen-sensitive adhesive composition and hydrogen-sensitive functional film of the present invention and their preparation methods and applications are further described below by way of examples. The examples are implemented based on the technical solution of the present invention, and detailed implementation methods and specific operation processes are given, but the protection scope of the present invention is not limited to the following examples.

[0119] The experimental methods in the following examples, unless otherwise specified, are all conventional methods in the art. The experimental materials used in the following examples, unless otherwise specified, are all commercially available.

[0120] In the following examples and comparative examples, the hydrogenochromic materials used were prepared according to the method described in patent application CN115711713A.

[0121] Example 1

[0122] The hydrogenochromic material used in this embodiment is prepared according to Example 4 in patent application CN115711713A, wherein, through XRD analysis, it is known that the crystal phase of tungsten trioxide is a hexagonal phase, the diffraction peak of 2θ at about 28° is attributed to the (002) crystal plane, the diffraction peak of 2θ at about 22° is attributed to the (100) crystal plane, and the diffraction peak of 2θ at about 14° is attributed to the (001) crystal plane, and the relative intensities of these three characteristic diffraction peaks satisfy: I (002) =1.07×I 100) =1.87×I (001) ; TEM analysis showed that the microscopic morphology of tungsten trioxide was a nanorod bundle stacked by multiple nanorods, the length of the nanorod bundle was about 900nm, the diameter was about 80nm, and the diameter of a single nanorod was about 8nm; the reflectivity of tungsten trioxide to visible light in the wavelength range of 400-750nm was greater than 50%; the content of platinum nanoparticles on the hydrogen-induced chromic material was measured by X-ray fluorescence analysis to be 0.35wt.%, the size of the platinum nanoparticles was less than 2nm, and the dispersion of metal platinum on tungsten trioxide was 76%; the initial reduction temperature of the hydrogen-induced chromic material to hydrogen was 46°C.

[0123] The transparent substrate used in this embodiment is a polyethylene terephthalate film (PET film) with a thickness of 125 μm and a light transmittance of 93%.

[0124] (1) grinding the hydrochromic material with a grinder to obtain a hydrochromic material powder having a particle size of less than 30 μm;

[0125] (2) 2 g of hydrogen-induced color-changing material powder was mixed with 130 g of deionized water, 1 g of sodium n-dodecyl sulfate and 1 g of sodium n-dodecylbenzene sulfonate were added, and 12 g of nano titanium dioxide (particle diameter was 20 nm) was added, and emulsified at 65° C. to obtain a hydrogen-sensitive functional material emulsion;

[0126] (3) adding 30 g of n-butyl acrylate, 20 g of acrylic acid, 10 g of isooctyl acrylate and 0.5 g of azobisisobutyronitrile to the hydrogen-sensitive functional material emulsion of step (2), stirring the mixture at 40° C. with a high-speed stirrer at 800 rpm for 1 h to obtain a hydrogen-sensitive adhesive composition;

[0127] (4) Polyethyleneimine (average molecular weight Mw=600) with a thickness of 5 μm was uniformly coated on the transparent substrate, and the hydrogen-sensitive adhesive composition obtained in step (3) was coated thereon. The thickness of the hydrogen-sensitive color-changing layer was 30 μm, and the amount of the hydrogen-induced color-changing material was 15 g / m 2 ;

[0128] (5) A release layer (obtained by fluorine coating on the surface of a PET film, with a peeling force of <10 g / 25 mm) is covered on the hydrogen-sensitive color-changing layer to obtain a flexible hydrogen-sensitive functional film A1.

[0129] Example 2

[0130] The hydrogenochromic material used in this embodiment is prepared according to Example 5 in patent application CN115711713A, wherein, through XRD analysis, it is known that the crystal phase of tungsten trioxide is a hexagonal phase, the diffraction peak of 2θ at about 28° is attributed to the (002) crystal plane, the diffraction peak of 2θ at about 22° is attributed to the (100) crystal plane, and the diffraction peak of 2θ at about 14° is attributed to the (001) crystal plane, and the relative intensities of these three characteristic diffraction peaks satisfy: I (002) =0.95×I 100) =1.35×I (001) ; TEM analysis showed that the microscopic morphology of tungsten trioxide was a nanorod bundle stacked by multiple nanorods, the length of the nanorod bundle was about 800nm, the diameter was about 60nm, and the diameter of a single nanorod was about 6nm; the reflectivity of tungsten trioxide to visible light in the wavelength range of 400-750nm was greater than 50%; the content of platinum nanoparticles on the hydrogen-induced chromic material was measured by X-ray fluorescence analysis to be 0.9wt.%, the size of the platinum nanoparticles was less than 2nm, and the dispersion of metal platinum on tungsten trioxide was 77%; the initial reduction temperature of the hydrogen-induced chromic material to hydrogen was 44°C.

[0131] The transparent substrate used in this embodiment is a polyethylene film (PE film) with a thickness of 200 μm and a light transmittance of 93%.

[0132] (1) grinding the hydrogen-sensitive functional material with a grinder to obtain a hydrogen-induced color-changing material powder with a particle size of less than 15 μm;

[0133] (2) 3.2 g of hydrogen-sensitive functional material powder was mixed with 145 g of deionized water, 1.5 g of sodium n-dodecylbenzene sulfonate and 1 g of sodium dialkyl-2-sulfosuccinate (purchased from Sinopharm Reagent Company, AR grade) were added, and 8 g of nano-titanium dioxide (particle diameter of 20 nm) was added, and emulsified at 50° C. to obtain a hydrogen-sensitive functional material emulsion;

[0134] (3) Add 25 g of n-butyl acrylate, 15 g of isooctyl acrylate, 15 g of hydroxyethyl acrylate and 0.2 g of azobisisobutyronitrile to the hydrogen-sensitive functional material emulsion of step (2), and stir the mixture at 35° C. with a high-speed stirrer at 600 rpm for 3 h to obtain a hydrogen-sensitive adhesive composition;

[0135] (4) Polyethyleneimine (average molecular weight Mw=600) with a thickness of 5 μm was uniformly coated on the transparent substrate, and the hydrogen-sensitive adhesive composition obtained in step (3) was coated thereon. The thickness of the hydrogen-sensitive color-changing layer was 25 μm, and the amount of the hydrogen-induced color-changing material was 10 g / m 2 ;

[0136] (5) Covering the hydrogen-sensitive color-changing layer with a release layer (obtained by fluorine coating on the surface of a PE film, with a peeling force of <10 g / 25 mm) to obtain a flexible hydrogen-sensitive functional film A2.

[0137] Example 3

[0138] The hydrogenochromic material used in this embodiment is prepared according to Example 6 of patent application CN115711713A, wherein, through XRD analysis, it is known that the crystal phase of tungsten trioxide is a hexagonal phase, the diffraction peak of 2θ at about 28° is attributed to the (002) crystal plane, the diffraction peak of 2θ at about 22° is attributed to the (100) crystal plane, and the diffraction peak of 2θ at about 14° is attributed to the (001) crystal plane, and the relative intensities of these three characteristic diffraction peaks satisfy: I (002) =1.07×I 100) =1.87×I (001) ; TEM analysis showed that the microscopic morphology of tungsten trioxide was a nanorod bundle stacked by multiple nanorods, the length of the nanorod bundle was about 900nm, the diameter was about 80nm, and the diameter of a single nanorod was about 8nm; the reflectivity of tungsten trioxide to visible light in the wavelength range of 400-750nm was greater than 50%; the content of platinum nanoparticles on the hydrogen-induced chromic material was measured by X-ray fluorescence analysis to be 0.24wt.%, the size of the platinum nanoparticles was less than 2nm, and the dispersion of metal platinum on tungsten trioxide was 71%; the initial reduction temperature of the hydrogen-induced chromic material to hydrogen was 47°C.

[0139] The transparent substrate used in this embodiment is a polyethylene terephthalate film (PET film) with a thickness of 175 μm and a light transmittance of 92%.

[0140] (1) grinding the hydrogen-sensitive functional material with a grinder to obtain a hydrogen-induced color-changing material powder with a particle size of less than 35 μm;

[0141] (2) 4.5 g of hydrogen-sensitive functional material powder was mixed with 150 g of deionized water, 1 g of sodium n-dodecylbenzene sulfonate and 2 g of sodium alkyl allyloxy polyoxyethylene phosphate (purchased from Sigma-Aldrich, AR grade) were added, and 10 g of nano titanium dioxide (particle diameter of 20 nm) was added, and emulsified at 55° C. to obtain a hydrogen-sensitive functional material emulsion;

[0142] (3) adding 40 g of 2-methoxyethyl acrylate, 20 g of isooctyl acrylate, 10 g of hydroxyethyl acrylate and 0.7 g of azobisisobutyronitrile to the hydrogen-sensitive functional material emulsion of step (2), stirring the mixture at 55° C. with a high-speed stirrer at 850 rpm for 2.3 h to obtain a hydrogen-sensitive adhesive composition;

[0143] (4) Polyethyleneimine (average molecular weight Mw=600) with a thickness of 5 μm was uniformly coated on the transparent substrate, and the hydrogen-sensitive adhesive composition obtained in step (3) was coated thereon. The thickness of the hydrogen-sensitive color-changing layer was 40 μm, and the amount of the hydrogen-induced color-changing material was 22 g / m 2 ;

[0144] (5) A release layer (obtained by fluorine coating on the surface of a PET film, with a peeling force of <10 g / 25 mm) is covered on the hydrogen-sensitive color-changing layer to obtain a flexible hydrogen-sensitive functional film A3.

[0145] Example 4

[0146] The hydrogenochromic material used in this embodiment is prepared according to Example 7 of patent application CN115711713A, wherein, through XRD analysis, it is known that the crystal phase of tungsten trioxide is a hexagonal phase, the diffraction peak of 2θ at about 28° is attributed to the (002) crystal plane, the diffraction peak of 2θ at about 22° is attributed to the (100) crystal plane, and the diffraction peak of 2θ at about 14° is attributed to the (001) crystal plane, and the relative intensities of these three characteristic diffraction peaks satisfy: I (002) =1.07×I 100) =1.87×I (001) ; TEM analysis showed that the microscopic morphology of tungsten trioxide was a nanorod bundle stacked by multiple nanorods, the length of the nanorod bundle was about 900nm, the diameter was about 80nm, and the diameter of a single nanorod was about 8nm; the reflectivity of tungsten trioxide to visible light in the wavelength range of 400-750nm was greater than 50%; the content of platinum nanoparticles on the hydrogen-induced chromic material was measured by X-ray fluorescence analysis to be 0.62wt.%, the size of the platinum nanoparticles was less than 2nm, and the dispersion of metal platinum on tungsten trioxide was 73%; the initial reduction temperature of the hydrogen-induced chromic material to hydrogen was 45°C.

[0147] The transparent substrate used in this embodiment is a polyethylene terephthalate film (PET film) with a thickness of 75 μm and a light transmittance of 95%.

[0148] (1) grinding the hydrogen-sensitive functional material with a grinder to obtain a hydrogen-induced color-changing material powder with a particle size of less than 22 μm;

[0149] (2) 3.8 g of hydrogen-sensitive functional material powder was mixed with 122 g of deionized water, 2.2 g of sodium dialkyl-2-sulfosuccinate and 5 g of nano-titanium dioxide (particle diameter of 20 nm) were added, and emulsification treatment was performed at 62° C. to obtain a hydrogen-sensitive functional material emulsion;

[0150] (3) Add 60 g of n-butyl acrylate, 15 g of hydroxyethyl acrylate and 0.4 g of azobisisobutyronitrile to the hydrogen-sensitive functional material emulsion of step (2), and stir the mixture at 52° C. with a high-speed stirrer at 650 rpm for 4 h to obtain a hydrogen-sensitive adhesive composition;

[0151] (4) Polyethyleneimine (average molecular weight Mw=600) with a thickness of 5 μm is uniformly coated on the transparent substrate, and the hydrogen-sensitive adhesive composition obtained in step (3) is coated thereon, and the thickness of the hydrogen-sensitive color-changing layer is 28 μm, wherein the amount of hydrogen-sensitive leakage detection material used is 18 g / m 2 ;

[0152] (5) A release layer (obtained by fluorine coating on the surface of a PET film, with a peeling force of <10 g / 25 mm) is covered on the hydrogen-sensitive color-changing layer to obtain a flexible hydrogen-sensitive functional film A4.

[0153] Example 5

[0154] The hydrogenochromic material used in this embodiment is prepared according to Example 8 in patent application CN115711713A, wherein XRD analysis shows that the crystal phase of tungsten trioxide is hexagonal, the diffraction peak of 2θ at about 28° is attributed to the (002) crystal plane, the diffraction peak of 2θ at about 22° is attributed to the (100) crystal plane, and the diffraction peak of 2θ at about 14° is attributed to the (001) crystal plane, and the relative intensities of these three characteristic diffraction peaks satisfy: I (002) =1.07×I 100) =1.87×I (001) ; TEM analysis showed that the microscopic morphology of tungsten trioxide was a nanorod bundle stacked by multiple nanorods, the length of the nanorod bundle was about 900nm, the diameter was about 80nm, and the diameter of a single nanorod was about 8nm; the reflectivity of tungsten trioxide to visible light in the wavelength range of 400-750nm was greater than 50%; the content of platinum nanoparticles on the hydrogen-induced chromic material was measured by X-ray fluorescence analysis to be 0.97wt.%, the size of the platinum nanoparticles was less than 2nm, and the dispersion of metal platinum on tungsten trioxide was 80%; the initial reduction temperature of the hydrogen-induced chromic material to hydrogen was 40°C.

[0155] The transparent substrate used in this embodiment is a polyethylene terephthalate film (PET film) with a thickness of 250 μm and a light transmittance of 91%.

[0156] (1) grinding the hydrogen-sensitive functional material with a grinder to obtain a hydrogen-induced color-changing material powder with a particle size of less than 8 μm;

[0157] (2) 1.8 g of hydrogen-sensitive functional material powder was mixed with 85 g of deionized water, 0.5 g of sodium n-dodecyl sulfate and 1.8 g of sodium dialkyl-2-sulfosuccinate were added, and 6.5 g of nano-titanium dioxide (particle diameter of 20 nm) was added, and emulsified at 73° C. to obtain a hydrogen-sensitive functional material emulsion;

[0158] (3) adding 45 g of 2-methoxyethyl acrylate, 12 g of hydroxyethyl acrylate and 0.15 g of azobisisobutyronitrile to the hydrogen-sensitive functional material emulsion of step (2), stirring the mixture at 38° C. with a high-speed stirrer at 720 rpm for 3.5 h to obtain a hydrogen-sensitive adhesive composition;

[0159] (4) Polyethyleneimine (average molecular weight Mw=600) with a thickness of 5 μm was uniformly coated on the transparent substrate, and the hydrogen-sensitive adhesive composition obtained in step (3) was coated thereon. The thickness of the hydrogen-sensitive color-changing layer was 10 μm, and the amount of the hydrogen-induced color-changing material was 11 g / m 2 ;

[0160] (5) A release layer (obtained by fluorine coating on the surface of a PET film, with a peeling force of <10 g / 25 mm) is covered on the hydrogen-sensitive color-changing layer to obtain a flexible hydrogen-sensitive functional film A5.

[0161] Example 6

[0162] A hydrogen-sensitive adhesive composition and a flexible hydrogen-sensitive functional film were prepared according to the method of Example 5, except that in step (4), the hydrogen-sensitive adhesive composition was coated to form a hydrogen-sensitive color-changing layer with a thickness of 20 μm, thereby obtaining a flexible hydrogen-sensitive functional film A6.

[0163] Example 7

[0164] A hydrogen-sensitive adhesive composition and a flexible hydrogen-sensitive functional film were prepared according to the method of Example 6, except that in step (2), no nano-titanium dioxide was added to obtain a flexible hydrogen-sensitive functional film A7.

[0165] Example 8

[0166] A hydrogen-sensitive adhesive composition and a flexible hydrogen-sensitive functional film were prepared according to the method of Example 6, except that in step (3), 45 g of ethyl acrylate and 12 g of propyl acrylate were added as polymerization monomers to obtain a flexible hydrogen-sensitive functional film A8.

[0167] Comparative Example 1

[0168] A hydrogen-sensitive adhesive composition and a flexible hydrogen-sensitive functional film were prepared according to the method of Example 7, except that in step (1), a hydrogen-chromic material powder having a particle size not greater than 150 μm was obtained by grinding, and in step (4), the hydrogen-sensitive adhesive composition was coated to form a hydrogen-sensitive color-changing layer with a thickness of 62 μm, thereby obtaining a flexible hydrogen-sensitive functional film D1.

[0169] Comparative Example 2

[0170] A hydrogen-sensitive adhesive composition and a flexible hydrogen-sensitive functional film were prepared according to the method of Example 7, except that in step (2), no emulsifier (i.e., sodium n-dodecyl sulfate and sodium dialkyl-2-sulfosuccinate) was added to obtain a flexible hydrogen-sensitive functional film D2.

[0171] Comparative Example 3

[0172] A hydrogen-sensitive adhesive composition and a flexible hydrogen-sensitive functional film were prepared according to the method of Example 7, except that in step (3), all the added polymerization monomers were acrylic acid, thereby obtaining a flexible hydrogen-sensitive functional film D3.

[0173] Test Case

[0174] The performance of the flexible hydrogen-sensitive functional membranes prepared in the above examples and comparative examples was tested according to the following method:

[0175] (1) Test method for environmental adaptability of flexible hydrogen-sensitive functional membrane

[0176] With reference to GB / T 18244-2000 "Aging Test Method for Building Waterproof Materials", the aging performance test was carried out in the Xe3 xenon lamp test chamber produced by Q-SUN. The aging process simulates the influence of multiple environmental factors such as light, rain, temperature, and humidity.

[0177] (2) Testing method for the color change response time of the flexible hydrogen-sensitive functional film to 4 vol% hydrogen and to 10 vol% hydrogen

[0178] The hydrogen discoloration performance test refers to the method disclosed in CN115711713A. The amount of hydrogen and argon entering is controlled by a mass flow meter, and the gas of appropriate concentration is configured for testing.

[0179] Table 1

[0180]

[0181] It can be seen from the results in Table 1 that the hydrogen-sensitive functional membrane of the present invention has a rapid response capability to hydrogen and has good environmental adaptability.

[0182] The preferred embodiments of the present invention are described in detail above, but the present invention is not limited thereto. Within the technical concept of the present invention, the technical solution of the present invention can be subjected to a variety of simple modifications, including the combination of various technical features in any other suitable manner, and these simple modifications and combinations should also be regarded as the contents disclosed by the present invention and belong to the protection scope of the present invention.

Claims

1. A hydrogen-sensitive adhesive composition, It is characterized in that The hydrogen-sensitive adhesive composition contains a hydrogen-chromic material, a polyacrylate, an initiator and an anionic emulsifier, wherein the hydrogen-chromic material includes hexagonal tungsten trioxide and precious metal nanoparticles, the hexagonal tungsten trioxide has a microstructure of nanorod bundles formed by stacking multiple bundles of nanorods, and the dispersion of the precious metal nanoparticles on the hexagonal tungsten trioxide is ≥70%, preferably ≥75%, and more preferably ≥80%; the particle size of the hydrogen-chromic material is less than 100 μm, preferably 1-60 μm.

2. The hydrogen-sensitive adhesive composition according to claim 1, It is characterized in that Relative to 100 parts by weight of the polyacrylate, the content of the hydrogenochromic material is 1-10 parts by weight, preferably 3-7 parts by weight; the content of the initiator is 0.1-2 parts by weight, preferably 0.2-1.2 parts by weight; the content of the anionic emulsifier is 1-10 parts by weight, preferably 2.5-5 parts by weight.

3. The hydrogen-sensitive adhesive composition according to claim 1, It is characterized in that In the hydrogen-induced chromic material, based on the total weight of the hydrogen-induced chromic material, the content of the hexagonal tungsten trioxide is 98.5-99.9% by weight, and the content of the noble metal nanoparticles is 0.1-1.5% by weight; Preferably, the noble metal nanoparticles are at least one of platinum nanoparticles, palladium nanoparticles, rhodium nanoparticles and gold nanoparticles, more preferably platinum nanoparticles; Preferably, the average size of the noble metal nanoparticles is ≤5 nm, preferably ≤2 nm; Preferably, the initial reduction temperature of the hydrogen-induced chromic material to hydrogen is ≤100°C, preferably ≤80°C, more preferably ≤60°C.

4. The hydrogen-sensitive adhesive composition according to any one of claims 1 to 3, It is characterized in that The polyacrylate is a polymer formed by polymerized monomers, and the polymerized monomers are selected from at least one of acrylic acid, ethyl acrylate, propyl acrylate, isopropyl acrylate, n-butyl acrylate, tert-butyl acrylate, isobutyl acrylate, isooctyl acrylate, hydroxyethyl acrylate and 2-methoxyethyl acrylate; Preferably, the polymerizable monomers are selected from at least two of acrylic acid, n-butyl acrylate, isooctyl acrylate, hydroxyethyl acrylate and 2-methoxyethyl acrylate.

5. The hydrogen-sensitive adhesive composition according to any one of claims 1 to 3, It is characterized in that The initiator is at least one of azobisisobutyronitrile, dibenzoyl peroxide and tert-butyl perbenzoate.

6. The hydrogen-sensitive adhesive composition according to any one of claims 1 to 3, It is characterized in that The anionic emulsifier is selected from one or any combination of two or more of alkyl sodium sulfate, alkyl sodium benzene sulfonate, dialkyl sodium 2-sulfosuccinate and alkyl allyloxy polyoxyethylene sodium phosphate.

7. The hydrogen-sensitive adhesive composition according to any one of claims 1 to 3, It is characterized in that The hydrogen-sensitive adhesive composition also contains an anti-ultraviolet additive; Preferably, relative to 100 parts by weight of the polyacrylate, the content of the anti-ultraviolet auxiliary agent is 3-30 parts by weight, preferably 6-26 parts by weight; Preferably, the anti-ultraviolet additive is nano titanium dioxide; Preferably, the particle size of the nano titanium dioxide is 1-100 nm.

8. A hydrogen-sensitive functional membrane, It is characterized in that The hydrogen-sensitive functional film comprises a transparent base layer and a hydrogen-sensitive color-changing layer located on one surface of the transparent base layer, wherein the hydrogen-sensitive color-changing layer is the hydrogen-sensitive adhesive composition according to any one of claims 1 to 7.

9. The hydrogen-sensitive functional membrane according to claim 8, It is characterized in that The thickness of the hydrogen-sensitive color-changing layer is 1-60 μm, preferably 3-40 μm.

10. The hydrogen-sensitive functional membrane according to claim 8 or 9, It is characterized in that The amount of hydrogen-induced color changing material is 0.5-40g / m 2 , preferably 1.5-25g / m 2 .

11. The hydrogen-sensitive functional membrane according to claim 8 or 9, It is characterized in that The transparent substrate layer is a polyethylene terephthalate film and / or a polyethylene film; Preferably, the thickness of the transparent substrate layer is 5-200 μm, more preferably 10-150 μm; Preferably, the light transmittance of the transparent substrate layer is greater than 90%.

12. The hydrogen-sensitive functional membrane according to any one of claims 8 to 11, It is characterized in that The color change response time to a hydrogen concentration of 4 volume % is less than 3 seconds, and the color change response time to a hydrogen concentration of 10 volume % is less than 1 second.

13. The hydrogen-sensitive functional membrane according to any one of claims 8 to 12, It is characterized in that The hydrogen-sensitive functional film further includes a release layer covering the hydrogen-sensitive color-changing layer.

14. A method for preparing a hydrogen-sensitive functional membrane, It is characterized in that The method comprises the following steps: (1) grinding the hydrochromic material to obtain a hydrochromic material powder having a particle size of less than 100 μm; (2) mixing the hydrochromic material powder, anionic emulsifier and optional anti-ultraviolet auxiliary agent, and emulsifying to obtain an emulsion; (3) mixing the emulsion obtained in step (2), a polymerization monomer and an initiator to obtain a hydrogen-sensitive adhesive composition; (4) coating a non-silicon release agent on one surface of the transparent substrate layer, and then coating the hydrogen-sensitive adhesive composition obtained in step (3) on the non-silicon release agent to form a hydrogen-sensitive color-changing layer; (5) Optionally, a release layer is covered on the hydrogen-sensitive color-changing layer; The hydrogen-induced color-changing material comprises hexagonal tungsten trioxide and noble metal nanoparticles, the hexagonal tungsten trioxide has a microstructure of nanorod bundles formed by stacking multiple bundles of nanorods, and the dispersion of the noble metal nanoparticles on the hexagonal tungsten trioxide is ≥70%, preferably ≥75%, and more preferably ≥80%; The polymerizable monomer described in step (3) is selected from at least one of acrylic acid, ethyl acrylate, propyl acrylate, isopropyl acrylate, n-butyl acrylate, tert-butyl acrylate, isobutyl acrylate, isooctyl acrylate, hydroxyethyl acrylate and 2-methoxyethyl acrylate.

15. The method according to claim 14, It is characterized in that In step (2), the emulsification temperature is 40-95°C, preferably 55-85°C.

16. The method according to claim 14, It is characterized in that In step (3), the mixing reaction is carried out under high-speed stirring, and the conditions of the mixing reaction include: temperature of 30-60° C., time of 0.5-5 h, and stirring speed of 200-1000 r / min.

17. Use of the hydrogen-sensitive functional membrane according to any one of claims 8 to 13 or the hydrogen-sensitive functional membrane prepared according to the method according to any one of claims 14 to 16 in hydrogen leakage detection.

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