Fluorine-containing composite adhesive, preparation method and device

Abstract

The embodiment of the invention discloses a fluorine-containing composite adhesive, a preparation method and a device. The fluorine-containing composite adhesive is prepared from the following components in parts by weight: 10 to 40 parts of bisphenol epoxy resin, 30 to 45 parts of resorcinol diglycidyl ether, 1 to 20 parts of fluorine-containing epoxy resin and 0.5 to 5 parts of cationic initiator, the fluorine-containing composite adhesive has high water and oxygen barrier rate and wettability, can improve the humidity and heat resistance and temperature change resistance of the prepared electrochromic device, and improves the problem of abnormal color development in the color fading state of the electrochromic device.

Description

Technical Field

[0001] The present invention relates to the field of packaging materials, and in particular to a fluorine-containing composite adhesive and a preparation method and device. Background Art

[0002] Electrochromic devices are made from electrochromic materials. When the material undergoes an electrochemical redox reaction, its light transmittance changes, creating a color-changing effect. They are currently widely used in products such as automotive rearview mirrors, car skylights, and virtual reality glasses. Existing electrochromic materials are mostly liquid, and a common process involves using a frame-type structural sealant to confine the material within the device. However, commonly used sealants for electrochromic devices can react with the electrochromic material, resulting in residual coloration at the interface between the sealant and the electrolyte. To address these issues, epoxy resin adhesives can be used to encapsulate liquid electrochromic devices. While epoxy resin adhesives offer relatively stable resistance to moisture and heat and electrolyte corrosion, they are also known to have a high hardness and elastic modulus. After curing between double-glazed windows, they can easily shrink or delaminate from the glass surface, leading to leakage under high temperature or high pressure. They also have poor water vapor resistance, making them difficult to pass reliability tests such as high-temperature and high-humidity testing, high-temperature boiling, humidity-heat cycling, and thermal shock testing, thus failing to meet the application requirements of solution-based electrochromic devices. Summary of the Invention

[0003] Based on this, the embodiments of the present invention provide a fluorine-containing composite adhesive and a preparation method and device. The fluorine-containing composite adhesive has a high water and oxygen barrier rate, high bonding strength, good moisture and heat resistance, good high temperature resistance, good resistance to electrolyte corrosion, and high wettability. It can solve the problem of coloring differences in electrochromic devices and can meet the industrial mass production needs of solution-type electrochromic devices.

[0004] In a first aspect, an embodiment of the present invention provides a fluorine-containing composite adhesive, which comprises the following components in parts by weight: 10-40 parts of bisphenol epoxy resin, 30-45 parts of resorcinol diglycidyl ether, 1-20 parts of fluorine-containing epoxy resin and 0.5-5 parts of cationic initiator.

[0005] In the embodiment of the present invention, the structure of the resorcinol diglycidyl ether is shown in formula (I):

[0006]

[0007] Wherein, n is selected from any integer between 0 and 25.

[0008] In an embodiment of the present invention, the fluorine-containing epoxy resin includes at least one of 4,4'-bis(hydroxyhexafluoroisopropyl)benzene diglycidyl ether, 1,3-bis(3-glycidyl ether tetrafluorophenoxy)-2-hydroxypropane, 1,4-bis(hydroxyhexafluoroisopropyl)benzene diglycidyl ether, 1,3-bis(hydroxyhexafluoroisopropyl)benzene diglycidyl ether, 1,4-bis(hydroxyhexafluoroisopropyl)n-perfluoropropylbenzene diglycidyl ether, 1,4-bis(hydroxyhexafluoroisopropyl)tetrafluorobenzene diglycidyl ether and 4,4'-bis(hydroxyhexafluoroisopropyl)octafluorobiphenyl diglycidyl ether.

[0009] In an embodiment of the present invention, the bisphenol epoxy resin includes at least one of bisphenol A epoxy resin and bisphenol F epoxy resin.

[0010] In the embodiment of the present invention, the structural formula of the bisphenol A epoxy resin is shown in formula (II):

[0011]

[0012] Wherein, n1 is selected from any integer between 0 and 25;

[0013] The structure of the bisphenol F epoxy resin is shown in formula (III):

[0014]

[0015] Wherein, n2 is selected from any integer between 0 and 25.

[0016] In the embodiment of the present invention, the chemical formula of the cationic initiator is AB, wherein A is selected from an aryl-substituted iodonium cation or an aryl-substituted sulfonium cation, and B is selected from SbF6 - PF6 - 、AsF6 - 、BF4 - 、B(C6F5)4 - 、B(C6F4OCF3)4 - or B(C6F4CF3)4 - .

[0017] In an embodiment of the present invention, the fluorine-containing composite adhesive further comprises at least one of a silane coupling agent, a plasticizer, a photoinitiator, a filler and insoluble particles.

[0018] In an embodiment of the present invention, in the fluorine-containing composite adhesive, the silane coupling agent is 1-15 parts, the plasticizer is 0.1-10 parts, the photoinitiator is 3-8 parts, and the filler is 20-40 parts by weight.

[0019] In an embodiment of the present invention, the silane coupling agent includes at least one of γ-aminopropyltriethoxysilane, γ-glycidoxypropyltrimethoxysilane and anilinomethyltrimethoxysilane;

[0020] The plasticizer comprises at least one of diisononyl adipate, diisononyl phthalate, diisodecyl phthalate, trioctyl trimellitate and tri-2-ethylhexyl trimellitate;

[0021] The photoinitiator includes a conjugated biphenyl organic compound, and the conjugated biphenyl organic compound includes at least one of 2-hydroxy-methylphenylpropane-1-one, 1-hydroxycyclohexylphenyl ketone, 2-methyl-1-(4-methylthiophenyl)-2-morpholinyl-1-propanone, benzoin dimethyl ether, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, ethyl dimethylaminobenzoate, benzophenone, 4-chlorobenzophenone, methyl o-benzoylbenzoate, 4-phenylbenzophenone, 2,4-diethylthiazolone, hexaaryldiimidazole and thioxanthone;

[0022] The filler includes at least one of an inorganic filler and an organic filler; the inorganic filler includes at least one of glass, silicon dioxide, talc, aluminum oxide, mica, ceramics, silicone rubber powder, calcium carbonate, aluminum nitride, carbon powder, kaolin, clay minerals and diatomaceous earth, and the particle size of the inorganic filler is 10 μm-50 μm; the organic filler includes at least one of polystyrene, polypropylene, polymethyl methacrylate, polybutylene and polypropylene carbonate, and the particle size of the organic filler is less than or equal to 50 μm,

[0023] The insoluble particles include one or more of plastic balls, glass balls and zirconium oxide balls, and the particle size of the insoluble particles is 100 μm-120 μm.

[0024] The fluorine-containing composite adhesive provided by the embodiment of the present invention contains a fluorine-containing epoxy resin and resorcinol diglycidyl ether. The fluorine-containing epoxy resin has high density, high hydrophobicity and high chemical stability, and can effectively block the erosion of water and oxygen, thereby improving the water and oxygen barrier properties of the fluorine-containing composite adhesive, thereby improving the moisture and heat resistance and temperature change resistance of the prepared electrochromic device. Resorcinol diglycidyl ether can improve the toughness and wettability of the fluorine-containing composite adhesive, reduce its elastic modulus, and facilitate the timely release of the stress generated during the curing process, reduce the curing shrinkage rate, make it less likely to shrink and crack, and avoid the electric field unevenness caused by the irregular edge of the glue path during the curing process of the fluorine-containing composite adhesive, thereby alleviating the problem of abnormal color development in the fading state of the electrochromic device.

[0025] In a second aspect, an embodiment of the present invention provides a method for preparing the fluorine-containing composite adhesive described in the first aspect, comprising: mixing 10-40 parts by weight of bisphenol epoxy resin, 30-45 parts by weight of resorcinol diglycidyl ether, 1-20 parts by weight of fluorine-containing epoxy resin and 0.5-5 parts by weight of cationic initiator to obtain the fluorine-containing composite adhesive.

[0026] The preparation method of the fluorine-containing composite adhesive provided by the embodiment of the present invention has a simple process, is easy to operate, and can realize industrialized large-scale preparation.

[0027] In a third aspect, an embodiment of the present invention provides an electrochromic device, comprising a first substrate and a second substrate stacked together, a first conductive layer being provided on a surface of the first substrate facing the second substrate, and a second conductive layer being provided on a surface of the second substrate facing the first substrate, an encapsulation layer being provided on the periphery of surfaces facing each other of the first conductive layer and the second conductive layer, the encapsulation layer being used to connect the first conductive layer and the second conductive layer to form a sealed accommodating space between the first conductive layer and the second conductive layer, the accommodating space being filled with an electrochromic electrolyte, and the encapsulation layer being made of the fluorine-containing composite adhesive provided by the first aspect of the present invention or the fluorine-containing composite adhesive prepared by the preparation method provided by the second aspect of the present invention.

[0028] The electrochromic device provided in an embodiment of the present invention is sealed by a fluorine-containing composite adhesive. The fluorine-containing composite adhesive has excellent resistance to moisture and heat, resistance to high and low temperature environmental changes, and resistance to chemical solvent corrosion, and also has a high water and oxygen barrier rate, which can improve the stability and service life of the device.

[0029] In a fourth aspect, an embodiment of the present invention provides an electronic device, comprising the electrochromic device provided in the third aspect. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the background technology, the drawings required for use in the embodiments of the present invention or the background technology will be described below.

[0031] Figure 1 1 is a schematic structural diagram of an electrochromic device provided by one embodiment of the present invention;

[0032] Figure 2 This is a temperature change curve of a wet heat cycle power-on test in one embodiment of the present invention.

[0033] Explanation of Figure Numbers

[0034] 100 - electrochromic device; 101 - first substrate; 102 - second substrate; 103 - first conductive layer; 104 - second conductive layer; 105 - packaging layer; 106 - electrochromic electrolyte. DETAILED DESCRIPTION

[0035] The embodiments of the present invention are described below with reference to the accompanying drawings.

[0036] An electrochromic device is a device made from electrochromic materials. The electrochromic effect is achieved by changing the transmittance of these materials after an electrochemical redox reaction. Currently, electrochromic devices are used in products such as automotive rearview mirrors, car skylights, and virtual reality glasses. Most existing electrochromic materials are liquid. To confine these materials to the electrochromic device, a common process involves using a frame-type sealant with a liquid inlet. The color-changing material is then vacuum-injected into the sealant, and the opening is then sealed with a UV (ultraviolet radiation) light-curing sealant. Commonly used color-changing materials are highly reactive and easily react with water and oxygen, causing device failure. Therefore, the water and oxygen barrier properties of the sealant play a critical role in the lifespan, safety, and performance of the electrochromic device.

[0037] The main sealing adhesives for electrochromic devices include composite polyimide siloxane resins, polyurethane resins, polyacrylic resins, etc. However, the main chain structures of these adhesives contain a large number of polar functional groups, which have electronic interactions with electrochromic materials, and the contact surface between the sealing adhesive and the electrolyte is prone to coloring residues. In order to solve the above problems, epoxy resin adhesives used in the field of LCD (Liquid Crystal Display) can be used to encapsulate liquid electrochromic devices. The main types include thermosetting epoxy resins, UV cationic epoxy resins, acrylic modified UV epoxy resins, silane modified epoxy resins, silicone rubber modified epoxy resins, AB type epoxy resins, etc. The main chain structure of the above epoxy resins does not contain polar functional groups, and has relatively stable moisture and heat resistance, as well as resistance to electrolyte erosion under power-on conditions, and has great potential to meet long-term use in harsh environments.

[0038] However, epoxy resins currently used in the LCD industry have a high hardness and elastic modulus. After curing between double layers of glass, they struggle to release stress, resulting in shrinkage or delamination from the glass surface. These resins are also prone to electrolyte leakage under high temperatures or high pressures, posing significant safety risks in products such as automobiles. Furthermore, epoxy resins such as acrylic-modified and silane-modified epoxy resins have poor moisture resistance, making them difficult to pass reliability tests such as high-temperature and high-humidity testing, high-temperature boiling, humidity-heat cycling, and thermal shock testing.

[0039] Based on this, an embodiment of the present invention provides a fluorine-containing composite adhesive, which includes the following components in parts by weight: 10-40 parts of bisphenol epoxy resin, 30-45 parts of resorcinol diglycidyl ether, 1-20 parts of fluorine-containing epoxy resin and 0.5-5 parts of cationic initiator.

[0040] The fluorine-containing composite adhesive provided by the embodiment of the present invention contains a fluorine-containing epoxy resin and resorcinol diglycidyl ether. The fluorine-containing epoxy resin has high density, high hydrophobicity and high chemical stability, and can effectively block the erosion of water and oxygen, thereby improving the water-oxygen barrier performance of the fluorine-containing composite adhesive. Resorcinol diglycidyl ether can improve the toughness and wettability of the fluorine-containing composite adhesive, reduce its elastic modulus, and facilitate the timely release of the stress generated during the curing process, reduce the curing shrinkage rate, make it less likely to shrink and crack, and avoid the electric field unevenness caused by the irregular edge of the glue path during the curing process of the fluorine-containing composite adhesive, thereby alleviating the problem of abnormal color development in the fading state of the electrochromic device.

[0041] In an embodiment of the present invention, the fluorine-containing epoxy resin includes at least one of 4,4'-bis(hydroxyhexafluoroisopropyl)benzene diglycidyl ether, 1,3-bis(3-glycidyl ether tetrafluorophenoxy)-2-hydroxypropane, 1,4-bis(hydroxyhexafluoroisopropyl)benzene diglycidyl ether, 1,3-bis(hydroxyhexafluoroisopropyl)benzene diglycidyl ether, 1,4-bis(hydroxyhexafluoroisopropyl)n-perfluoropropylbenzene diglycidyl ether, 1,4-bis(hydroxyhexafluoroisopropyl)tetrafluorobenzene diglycidyl ether and 4,4'-bis(hydroxyhexafluoroisopropyl)octafluorobiphenyl diglycidyl ether.

[0042] In an embodiment of the present invention, the weight of the fluorinated epoxy resin in the fluorinated composite adhesive is 1-20 parts. In some embodiments, the weight of the fluorinated epoxy resin in the fluorinated composite adhesive can be, for example, 1 part, 3 parts, 5 parts, 8 parts, 10 parts, 12 parts, 15 parts, 17 parts, or 20 parts. By controlling the content of the fluorinated epoxy resin in the fluorinated composite adhesive within an appropriate range, the present application can effectively control the cost while ensuring that the fluorinated composite adhesive provides excellent water and oxygen barrier properties, which is more conducive to large-scale industrial production.

[0043] In the embodiment of the present invention, the structural formula of resorcinol diglycidyl ether is shown in formula (I):

[0044]

[0045] Wherein, n is selected from any integer between 0-25; In some embodiments, n can be, for example, 0, 1, 2, 3, 4, 5, 6, 8, 10, 12, 15, 18, 20, 22, 24, or 25.

[0046] In an embodiment of the present invention, the weight proportion of resorcinol diglycidyl ether in the fluorine-containing composite adhesive is 30 parts to 45 parts. In some embodiments, the weight proportion of resorcinol diglycidyl ether in the fluorine-containing composite adhesive can be, for example, 30 parts, 32 parts, 34 parts, 35 parts, 36 parts, 38 parts, 40 parts, 42 parts, or 45 parts. Resorcinol diglycidyl ether can change the elastic modulus of the entire fluorine-containing composite adhesive. Controlling its content within an appropriate range can, on the one hand, avoid too little content, which may lead to the addition of more bisphenol epoxy resin, thereby causing the overall hardness of the fluorine-containing composite adhesive to be too high, which is not conducive to stress release; on the other hand, avoid excessive content, which may result in the overall softness of the fluorine-containing composite adhesive, reduced sealing performance, and reduced bonding strength.

[0047] In an embodiment of the present invention, the bisphenol epoxy resin includes at least one of bisphenol A epoxy resin and bisphenol F epoxy resin. In an embodiment of the present invention, the structural formula of the bisphenol A epoxy resin is shown in formula (II):

[0048]

[0049] Wherein, n1 is selected from any integer between 0 and 25; in some embodiments, n1 can be, for example, 0, 1, 2, 3, 4, 5, 6, 8, 10, 12, 15, 18, 20, 22, 24, or 25.

[0050] In the embodiment of the present invention, the structural formula of bisphenol F epoxy resin is shown in formula (III):

[0051]

[0052] Wherein, n2 is selected from any integer between 0 and 25; in some embodiments, n2 can be, for example, 0, 1, 2, 3, 4, 5, 6, 8, 10, 12, 15, 18, 20, 22, 24, or 25.

[0053] In an embodiment of the present invention, the weight ratio of the bisphenol epoxy resin in the fluorine-containing composite adhesive is 10-40 parts. In some embodiments, the weight ratio of the bisphenol epoxy resin in the fluorine-containing composite adhesive can be, for example, 10 parts, 12 parts, 15 parts, 17 parts, 19 parts, 20 parts, 22 parts, 25 parts, 28 parts, 30 parts, 35 parts, or 40 parts. The present application controls the content of the bisphenol epoxy resin in the fluorine-containing composite adhesive within a suitable range, so that the overall hardness of the fluorine-containing composite adhesive is moderate, and it has both excellent mechanical properties and sealing properties.

[0054] In the embodiment of the present invention, the chemical formula of the cationic initiator is AB, wherein A is selected from an aryl-substituted iodonium cation or an aryl-substituted sulfonium cation, and B is selected from SbF6 - PF6 -、AsF6 - 、BF4 - 、B(C6F5)4 - 、B(C6F4OCF3)4 - or B(C6F4CF3)4 - In some embodiments of the present invention, the aryl-substituted iodonium cation is Ar2I + , Ar is an aromatic group; the aromatic substituted sulfonium cation is Ar3S + , Ar is an aryl group. In some embodiments, the cationic initiator can be at least one of a diaryliodonium salt and a triarylsulfonium salt. Specifically, the cationic initiator can be at least one of diphenyliodonium hexafluoroantimonate, diphenyliodonium hexafluorophosphate, bis(p-tolyl)iodonium hexafluorophosphate, and a triarylsulfonium hexafluorophosphate.

[0055] In an embodiment of the present invention, the weight proportion of the cationic initiator in the fluorine-containing composite adhesive is 0.5 parts to 5 parts. In some embodiments, the weight proportion of the cationic initiator in the fluorine-containing composite adhesive can be, for example, 0.5 parts, 1 part, 1.5 parts, 2 parts, 2.5 parts, 3 parts, 3.5 parts, 4 parts, 4.5 parts or 5 parts. Cationic initiator is an important component that triggers the curing reaction of the adhesive. If the content is too low, it may cause the adhesive to cure more slowly or even fail to cure completely, which will reduce the overall strength of the product, resulting in unsatisfactory bonding effect, and may cause the joint to detach or separate. Excessive content of cationic initiator may trigger an overly fast curing reaction, causing the adhesive to generate excessive heat and internal stress, thereby causing shrinkage and cracking. Setting the content of cationic initiator within the above range can not only ensure the curing rate of the fluorine-containing composite adhesive, but also avoid shrinkage and cracking.

[0056] In an embodiment of the present invention, the fluorine-containing composite adhesive may further include at least one of a silane coupling agent, a plasticizer, a photoinitiator, a filler, and insoluble particles.

[0057] In an embodiment of the present invention, the silane coupling agent includes at least one of γ-aminopropyltriethoxysilane, γ-glycidoxypropyltrimethoxysilane, and anilinemethyltrimethoxysilane. The silane coupling agent can undergo a cross-linking reaction with the epoxy resin in the adhesive, increasing the strength and bond strength of the adhesive, thereby improving the adhesive's shear resistance. It can also improve the adhesive's fluidity and wettability, allowing the adhesive to be more evenly distributed on the substrate surface, increasing the contact area of the bonding surface, and thus enhancing the adhesion effect.

[0058] In embodiments of the present invention, the weight percentage of the silane coupling agent in the fluorinated composite adhesive can be 1 to 15 parts, which can enhance the adhesion of the fluorinated composite adhesive while not affecting its water and oxygen barrier properties. In some embodiments, the weight percentage of the silane coupling agent in the fluorinated composite adhesive can be, for example, 1 part, 3 parts, 5 parts, 7 parts, 10 parts, 12 parts, or 15 parts.

[0059] In an embodiment of the present invention, the plasticizer includes at least one of diisononyl adipate, diisononyl phthalate, diisodecyl phthalate, trioctyl trimellitate, and tri-2-ethylhexyl trimellitate. The plasticizer can increase the flexibility and ductility of the fluorine-containing composite adhesive, imparting greater elasticity and plasticity. This allows the adhesive to better adapt to substrate deformation under stress, thereby improving bond strength and durability.

[0060] In embodiments of the present invention, the plasticizer content in the fluorinated composite adhesive can range from 0.1 to 10 parts by weight, which increases the flexibility and ductility of the fluorinated composite adhesive while maintaining its water and oxygen barrier properties. In some embodiments, the plasticizer content in the fluorinated composite adhesive can range from 1 part, 2 parts, 3 parts, 4 parts, 5 parts, 6 parts, 7 parts, 8 parts, 9 parts, or 10 parts by weight.

[0061] In an embodiment of the present invention, the photoinitiator includes a conjugated biphenyl organic compound, specifically, the conjugated biphenyl organic compound includes at least one of 2-hydroxy-methylphenylpropane-1-one, 1-hydroxycyclohexylphenyl ketone, 2-methyl-1-(4-methylthiophenyl)-2-morpholinyl-1-propanone, benzoin dimethyl ether, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, dimethylaminobenzoic acid ethyl ester, benzophenone, 4-chlorobenzophenone, o-benzoylbenzoic acid methyl ester, 4-phenylbenzophenone, 2,4-diethylthiazolone, hexaaryldiimidazole and thioxanthone. The photoinitiator triggers the photocuring of the fluorine-containing composite adhesive after light irradiation, thereby enhancing the adhesion between the adhesive and the substrate. The photoinitiator can produce sufficient crosslinking under light irradiation to form a network structure with good affinity to the substrate, thereby increasing the contact area and adhesion between the adhesive and the substrate.

[0062] In embodiments of the present invention, the photoinitiator in the fluorinated composite adhesive comprises 3 to 8 parts by weight, which can initiate light-curing of the fluorinated composite adhesive while not affecting its water and oxygen barrier properties. In some embodiments, the photoinitiator in the fluorinated composite adhesive can comprise, for example, 3, 4, 5, 6, 7, or 8 parts by weight.

[0063] In embodiments of the present invention, the filler includes at least one of an inorganic filler and an organic filler. Specifically, the inorganic filler includes at least one of glass, silica, talc, alumina, mica, ceramics, silicone rubber powder, calcium carbonate, aluminum nitride, carbon powder, kaolin, clay minerals, and diatomaceous earth. The organic filler includes at least one of polystyrene, polypropylene, polymethyl methacrylate, polybutylene, and polypropylene carbonate. The filler can improve the elastic modulus and fluidity of the cured product of the fluorine-containing composite adhesive without compromising the stability during preparation and storage.

[0064] In an embodiment of the present invention, the inorganic filler may be spherical or quasi-spherical particles, and the particle size of the inorganic filler may be 10 μm-50 μm. Specifically, the particle size of the inorganic filler may be, for example, 10 μm, 15 μm, 20 μm, 25 μm, 30 μm, 35 μm, 40 μm, 45 μm, or 50 μm.

[0065] In an embodiment of the present invention, the organic filler may be spherical or quasi-spherical particles, and the particle size of the organic filler may be less than or equal to 50 μm. Specifically, the particle size of the organic filler may be, for example, 50 μm, 45 μm, 40 μm, 35 μm, 30 μm, 25 μm, 20 μm, 15 μm or 10 μm.

[0066] In embodiments of the present invention, the filler content in the fluorinated composite adhesive may be 20-40 parts by weight, which improves the elastic modulus and fluidity of the cured product of the fluorinated composite adhesive while maintaining its water and oxygen barrier properties. In some embodiments, the filler content in the fluorinated composite adhesive may be, for example, 20 parts, 22 parts, 25 parts, 27.5 parts, 30 parts, 32 parts, 35 parts, 37 parts, 38 parts, or 40 parts by weight.

[0067] In an embodiment of the present invention, when the fluorine-containing composite adhesive is used to bond the front and rear substrates of the electrochromic device, insoluble particles may be added. The insoluble particles may be plastic balls, glass balls or zirconia balls. The mass fraction of the insoluble particles in the fluorine-containing composite adhesive may be 1 / 1000-5 / 1000. In some embodiments, the diameter of the insoluble particles should be consistent with the spacing between the front and rear substrates of the electrochromic device, so that the front and rear substrates of the electrochromic device remain parallel and the spacing between the front and rear substrates remains consistent. In some embodiments, the particle size of the insoluble particles may be 100μm-120μm, and specifically, for example, may be 100μm, 105μm, 110μm, 115μm or 120μm.

[0068] An embodiment of the present invention also provides a method for preparing the fluorine-containing composite adhesive in any of the above embodiments, comprising: mixing 10-40 parts by weight of bisphenol epoxy resin, 30-45 parts by weight of resorcinol diglycidyl ether, 1-20 parts by weight of fluorine-containing epoxy resin and 0.5-5 parts by weight of cationic initiator to obtain the fluorine-containing composite adhesive.

[0069] The preparation method of the fluorine-containing composite adhesive provided by the embodiment of the present invention has a simple process, is easy to operate, and can realize industrialized large-scale preparation.

[0070] In an embodiment of the present invention, the bisphenol epoxy resin includes at least one of a bisphenol A epoxy resin and a bisphenol F epoxy resin.

[0071] In an embodiment of the present invention, the preparation of the fluorine-containing composite adhesive further comprises adding 1-15 parts by weight of a silane coupling agent, 0.1-10 parts by weight of a plasticizer, 3-8 parts by weight of a photoinitiator, and 20-40 parts by weight of a filler.

[0072] In some embodiments, the preparation of the fluorine-containing composite adhesive comprises the following steps:

[0073] S1. Add bisphenol A epoxy resin, bisphenol F epoxy resin, fluorinated epoxy resin, and resorcinol diglycidyl ether to a reaction vessel, then heat to 60°C and maintain for 30 minutes. Then, stir at 4000 r / min for 30-60 minutes using a high-speed disperser to thoroughly mix. Then, stop the machine, add the plasticizer, and continue stirring at 4000 r / min for 10 minutes. After uniform mixing, stop the machine.

[0074] S2. Adjust the speed of the high-speed disperser to 500r / min-800r / min, then slowly add the filler. When the powder filler is completely wetted and dissolved in the liquid phase, add the silane coupling agent and adjust the speed to 3000r / min-4000r / min for stirring. Keep the temperature at 60°C and stir for 60 minutes to ensure uniform mixing and complete reaction, then stop the machine.

[0075] S3. Cool the reactor to room temperature and place it in a light-shielding fume hood. Adjust the speed of the high-speed disperser to 500 r / min-800 r / min, then slowly add the cationic initiator and the photoinitiator, keep the temperature in the reactor not higher than 50° C., for example, 25° C.-50° C., stir for 60 minutes to mix evenly and react completely, and then shut down;

[0076] S4. Finally, the prepared mixture in the container is vacuumed, discharged, sieved, and packaged to obtain a fluorine-containing composite adhesive.

[0077] In an embodiment of the present invention, the mesh size of the sieve used in step S4 is selected based on the size of the filler. In some embodiments, the mesh size of the sieve used can be, for example, 100 mesh. In an embodiment of the present invention, the fluorine-containing composite adhesive is a liquid at 25° C. and can be stored in the dark at room temperature for more than 3 months.

[0078] In embodiments of the present invention, the fluorinated composite adhesive can be applied to the adherend using methods commonly known for sealants or adhesives. Specifically, the fluorinated composite adhesive can be applied to the adherend using methods such as automatic coating, spraying, inkjet coating, screen printing, gravure printing, dipping, spin coating, or a dispensing process.

[0079] In an embodiment of the present invention, the fluorine-containing composite adhesive can be cured by irradiation with light such as ultraviolet rays, visible light and active energy rays. The light mentioned here refers to light in a broad sense, including various active energy rays such as radiation such as α-rays and β-rays, electromagnetic waves such as γ-rays and X-rays, electron beam radiation, ultraviolet rays of about 100nm-400nm, and visible light of about 400nm-800nm. There is no special limitation on the light source used for curing, including but not limited to low-pressure mercury lamps, medium-pressure mercury lamps, high-pressure mercury lamps, ultra-high-pressure mercury lamps, black light lamps, microwave-excited mercury lamps, metal halide lamps, sodium lamps, halogen lamps, xenon lamps, LEDs, fluorescent lamps, sunlight, electron beam irradiation devices, etc. The irradiation dose of light irradiation can be greater than or equal to 3000mJ / cm 2 Furthermore, the irradiation dose may be greater than or equal to 7000 mJ / cm 2 .

[0080] In an embodiment of the present invention, the fluorine-containing composite adhesive can also be cured by thermosetting, and the curing temperature can be 80°C-150°C, and the curing time can be 1 hour-3 hours. In some embodiments, the curing temperature can be, for example, 80°C, 90°C, 100°C, 110°C, 120°C, 130°C, 140°C, or 150°C, and the curing time can be 1 hour, 1.5 hours, 2 hours, 2.5 hours, or 3 hours. In some embodiments, the fluorine-containing composite adhesive can adopt dual photothermal curing conditions to achieve better curing effect and help improve product performance.

[0081] like Figure 1As shown, the present application also provides an electrochromic device 100 including a first substrate 101 and a second substrate 102 stacked together, a first conductive layer 103 is provided on the surface of the first substrate 101 facing the second substrate 102, and a second conductive layer 104 is provided on the surface of the second substrate 102 facing the first substrate 101, and an encapsulation layer 105 is provided on the periphery of the surface facing each other of the first conductive layer 103 and the second conductive layer 104, and the encapsulation layer 105 is used to connect the first conductive layer 103 and the second conductive layer 104 to form a sealed accommodating space between the first conductive layer 103 and the second conductive layer 104, and the accommodating space is filled with an electrochromic electrolyte 106, and the encapsulation layer 105 includes the fluorine-containing composite adhesive described above or the fluorine-containing composite adhesive prepared by the preparation method described above.

[0082] In the embodiments of the present application, the first substrate 101 and the second substrate 102 can respectively provide support and protection for the first conductive layer 103 and the second conductive layer 104. In some embodiments of the present application, the first substrate 101 and the second substrate 102 can be made of transparent materials such as glass, PET (polyethylene terephthalate), PI (polyimide), PEN (polyethylene naphthalate), and sapphire; the materials of the first substrate 101 and the second substrate 102 can be the same or different.

[0083] In some embodiments of the present application, the first conductive layer 103 and the second conductive layer 104 have good optical transmittance, electrical conductivity, and transparency. In some embodiments of the present application, the first conductive layer 103 and the second conductive layer 104 can be, for example, ITO (indium tin oxide), AZO (zinc aluminum oxide), IZO (indium zinc oxide), etc.

[0084] In the embodiment of the present application, the electrochromic electrolyte 106 includes, but is not limited to, at least one of an organic electrochromic material, an inorganic electrochromic material, and a composite electrochromic material. The inorganic electrochromic material may be, but is not limited to, at least one of NiO, CO₃O₄, WO₃, TiO₂, and V₂O₅; the organic electrochromic material may be, but is not limited to, at least one of polyaniline, polypyrrole, polythiophene, polyfuran, phthalocyanine, phthalocyanine metal chelate, viologen, 9,10-anthraquinone, 2-2'-bipyridine, and tetrasaifenesin; and the composite electrochromic material may be, but is not limited to, an inorganic / inorganic, inorganic / organic, or organic / organic composite electrochromic material.

[0085] The present application also provides an electronic device comprising the electrochromic device described above. The electronic device includes electrochromic automobile rearview mirrors, automobile skylights, VR glasses, electrochromic windows for buildings and aircraft, sunglasses and goggles, and electrochromic displays.

[0086] The device provided in the embodiment of the present invention is sealed by a fluorine-containing composite adhesive. The fluorine-containing composite adhesive has excellent resistance to moisture and heat, resistance to high and low temperature environmental changes, and resistance to chemical solvent corrosion, and also has a high water and oxygen barrier rate, which can improve the stability and service life of the device.

[0087] The technical solution of the present invention is further illustrated below through specific examples and comparative examples.

[0088] Example 1

[0089] (1) Preparation of fluorine-containing composite adhesive

[0090] Add bisphenol A epoxy resin (9 parts), bisphenol F epoxy resin (10 parts), 4,4'-bis(hydroxyhexafluoroisopropyl)benzene diglycidyl ether (1 part), and resorcinol diglycidyl ether (38 parts) to the reaction vessel, then heat to 60°C and maintain for 30 minutes. Then use a high-speed disperser to stir at a speed of 4000 r / min for 30-60 minutes to fully mix. Then stop the machine, add the plasticizer trioctyl trimellitate (5 parts), and continue stirring at a speed of 4000 r / min for 10 minutes. After uniform mixing, stop the machine.

[0091] The speed of the high-speed disperser was adjusted to 500 r / min-800 r / min, and then talcum powder (27.5 parts) and plastic balls with a diameter of 100 μm (0.1 parts) were slowly added. When the powder filler was completely wetted and dissolved in the liquid phase, γ-glycidyloxypropyltrimethoxysilane (5 parts) was then added and the speed was adjusted to 3000 r / min-4000 r / min for stirring. The mixture was kept at 60°C and stirred for 60 minutes to ensure uniform mixing and complete reaction, and then the machine was stopped.

[0092] The reactor was cooled to room temperature and placed in a light-shielding fume hood. The speed of the high-speed disperser was adjusted to 500-800 r / min. Then, diphenyliodonium hexafluoroantimonate (1.5 parts) and 4-chlorobenzophenone (3 parts) were slowly added. The temperature in the reactor was kept below 50° C. and stirred for 60 minutes to ensure uniform mixing and complete reaction. The reactor was then shut down.

[0093] Finally, the prepared mixture in the container was vacuumed, discharged, passed through a 100-mesh sieve, and packaged to obtain the fluorine-containing composite adhesive of Example 1.

[0094] (2) Preparation of electrochromic devices

[0095] The fluorine-containing adhesive of Example 1 was uniformly dispensed into the electrochromic device with a width of 1.8 mm to 2.0 mm and a thickness of 100 μm. It was cured using an LED lamp with a total curing energy of 7000 mJ / cm 2, and then heated at 120° C. for 2 h. After the electrochromic solution was poured in, the opening was sealed with UV light-curing sealing glue to obtain the electrochromic device of Example 1 (length 25 cm, width 6.5 mm).

[0096] Example 2

[0097] The difference from Example 1 is that the weight proportion of 4,4'-bis(hydroxyhexafluoroisopropyl)benzene diglycidyl ether in the fluorine-containing adhesive is 3 parts.

[0098] Example 3

[0099] The difference from Example 1 is that the weight proportion of 4,4'-bis(hydroxyhexafluoroisopropyl)benzene diglycidyl ether in the fluorine-containing adhesive is 5 parts.

[0100] Example 4

[0101] The difference from Example 1 is that the weight proportion of 4,4'-bis(hydroxyhexafluoroisopropyl)benzene diglycidyl ether in the fluorine-containing adhesive is 8 parts.

[0102] Example 5

[0103] The difference from Example 1 is that the weight proportion of 4,4'-bis(hydroxyhexafluoroisopropyl)benzene diglycidyl ether in the fluorine-containing adhesive is 20 parts.

[0104] Example 6

[0105] The difference from Example 3 is that 4,4'-bis(hydroxyhexafluoroisopropyl)octafluorobiphenyl diglycidyl ether is used instead of 4,4'-bis(hydroxyhexafluoroisopropyl)benzene diglycidyl ether.

[0106] Example 7

[0107] The difference from Example 3 is that the weight proportion of resorcinol diglycidyl ether in the fluorine-containing adhesive is 30 parts.

[0108] Example 8

[0109] The difference from Example 3 is that the weight proportion of resorcinol diglycidyl ether in the fluorine-containing adhesive is 45 parts.

[0110] Example 9

[0111] The difference from Example 3 is that the weight proportion of bisphenol A epoxy resin in the fluorine-containing adhesive is 5 parts, the weight proportion of bisphenol F epoxy resin is 5 parts, and the weight proportion of diphenyliodonium hexafluoroantimonate is 0.5 parts.

[0112] Example 10

[0113] The difference from Example 3 is that the weight proportion of bisphenol A epoxy resin in the fluorine-containing adhesive is 20 parts, the weight proportion of bisphenol F epoxy resin is 20 parts, and the weight proportion of diphenyliodonium hexafluoroantimonate is 5 parts.

[0114] Comparative Example 1

[0115] The difference from Example 1 is that the fluorine-containing adhesive does not contain 4,4'-bis(hydroxyhexafluoroisopropyl)benzene diglycidyl ether.

[0116] Comparative Example 2

[0117] The difference from Example 1 is that the weight proportion of 4,4'-bis(hydroxyhexafluoroisopropyl)benzene diglycidyl ether in the fluorine-containing adhesive is 30 parts.

[0118] Aging resistance test

[0119] The electrochromic devices of Examples 1-10 and Comparative Examples 1-2 were subjected to high-temperature water boiling, high-temperature and high-humidity, wet-heat cycle power-on, hot-cold shock, and room-temperature power-on and power-off tests:

[0120] High-temperature boiling water test method: The electrochromic device was placed in a water bath maintained at 90°C. The power was turned off and the duration for which the electrochromic device remained leak-proof under the high-temperature boiling water test conditions was recorded. The test results are shown in Table 1.

[0121] High-temperature and high-humidity test method: Place the electrochromic device in a constant temperature chamber, adjust the temperature to 85°C and the humidity to 90%, and power it on at a test voltage of 1.2V. Use the control software to make the device cycle, with power on for 30 seconds and power off for 30 seconds as one cycle. Record the length of time the electrochromic device remains leak-proof under high-temperature and high-humidity test conditions. The test results are shown in Table 1.

[0122] Wet heat cycle test method: Place the electrochromic device in a constant temperature box, and the temperature changes as shown in the following example: Figure 2 As shown, odd-numbered cycles include a low-temperature section, and even-numbered cycles do not include a low-temperature section (the low temperature is replaced by 23°C). The humidity is not controlled below 23°C. The humidity in the heating and constant temperature sections is (93±3)% RH, and the humidity in the cooling stage is greater than or equal to 80% RH. The time it takes for the electrochromic device to remain leak-free under the wet-heat cycle power-on test conditions is recorded. The test results are shown in Table 1.

[0123] Thermal shock test method: The electrochromic device was tested at 85°C and -40°C. One cycle consisted of 30 minutes at 85°C and 30 minutes at -40°C. The switching time was less than 30 seconds. The duration for which the electrochromic device remained leak-proof under high temperature and high humidity test conditions was recorded. The test results are shown in Table 1.

[0124] Normal temperature power-on / off test: After the electrochromic device was continuously powered at 1.2V for 50 minutes, the color difference of the adhesive edge of the electrochromic device in the power-off state was observed. The test results are shown in Table 1.

[0125] Table 1 Test results of aging resistance

[0126] Serial number High temperature boiling / h High temperature and high humidity / h Wet heat cycle / h Thermal shock / h Normal temperature power on and off (color difference) Example 1 160 280 290 320 slight Example 2 360 660 360 360 none Example 3 740 1180 360 360 none Example 4 1000 1440 360 360 none Example 5 850 1300 360 360 none Example 6 810 1240 360 360 none Example 7 740 1200 360 360 none Example 8 680 970 360 360 none Example 9 800 1250 360 360 none Example 10 700 1090 360 360 none Comparative Example 1 72 180 240 260 serious Comparative Example 2 140 250 160 180 More obvious

[0127] As can be seen from Table 1, compared with Comparative Example 1 and Comparative Example 2, the electrochromic devices of Examples 1-10 have better resistance to high-temperature boiling water, high-temperature and high-humidity, moisture-heat cycle resistance, and cold and hot shock resistance, and the color difference of the adhesive edge is smaller in the power-off state, indicating that the fluorine-containing composite adhesive provided by the embodiment of the present invention is used to encapsulate the electrochromic device. Since the fluorine-containing composite adhesive contains a fluorine-containing epoxy resin and its weight content is controlled within an appropriate range, the moisture-heat and temperature change resistance of the electrochromic device can be effectively improved, and the problem of color difference in the faded state of the electrochromic device can be improved.

[0128] The above-described embodiments merely illustrate several implementations of the present invention, and while their descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that a person skilled in the art would be able to make numerous variations and improvements without departing from the spirit of the present invention, all of which fall within the scope of protection of the present invention. Therefore, the scope of protection of the present invention shall be determined by the appended claims.

Claims

1. A fluorine-containing composite adhesive, characterized in that: The fluorine-containing composite adhesive comprises the following components in parts by weight: 10-40 parts of bisphenol epoxy resin, 30-45 parts of resorcinol diglycidyl ether, 1-20 parts of fluorine-containing epoxy resin and 0.5-5 parts of cationic initiator.

2. The fluorine-containing composite adhesive according to claim 1, characterized in that The structure of the resorcinol diglycidyl ether is shown in formula (I): Wherein, n is selected from any integer between 0 and 25.

3. The fluorine-containing composite adhesive according to claim 1 or 2, characterized in that: The fluorine-containing epoxy resin includes at least one of 4,4'-bis(hydroxyhexafluoroisopropyl)benzene diglycidyl ether, 1,3-bis(3-glycidyltetrafluorophenoxy)-2-hydroxypropane, 1,4-bis(hydroxyhexafluoroisopropyl)benzene diglycidyl ether, 1,3-bis(hydroxyhexafluoroisopropyl)benzene diglycidyl ether, 1,4-bis(hydroxyhexafluoroisopropyl)n-perfluoropropylbenzene diglycidyl ether, 1,4-bis(hydroxyhexafluoroisopropyl)tetrafluorobenzene diglycidyl ether and 4,4'-bis(hydroxyhexafluoroisopropyl)octafluorobiphenyl diglycidyl ether.

4. The fluorine-containing composite adhesive according to any one of claims 1 to 3, characterized in that: The bisphenol epoxy resin includes at least one of bisphenol A epoxy resin and bisphenol F epoxy resin.

5. The fluorine-containing composite adhesive according to claim 4, characterized in that: The structural formula of the bisphenol A epoxy resin is shown in formula (II): Wherein, n1 is selected from any integer between 0 and 25; The structure of the bisphenol F epoxy resin is shown in formula (III): Wherein, n2 is selected from any integer between 0 and 25.

6. The fluorine-containing composite adhesive according to any one of claims 1 to 5, characterized in that: The chemical formula of the cationic initiator is AB, wherein A is selected from an aryl-substituted iodonium cation or an aryl-substituted sulfonium cation, and B is selected from SbF6 - PF6 - 、AsF6 - 、BF4 - 、B(C6F5)4 - 、B(C6F4OCF3)4 - or B(C6F4CF3)4 - .

7. The fluorine-containing composite adhesive according to any one of claims 1 to 6, characterized in that: The fluorine-containing composite adhesive further comprises at least one of a silane coupling agent, a plasticizer, a photoinitiator, a filler and insoluble particles.

8. The fluorine-containing composite adhesive according to claim 7, characterized in that In the fluorine-containing composite adhesive, by weight, the silane coupling agent is 1 part to 15 parts, the plasticizer is 0.1 parts to 10 parts, the photoinitiator is 3 parts to 8 parts, and the filler is 20 parts to 40 parts.

9. The fluorine-containing composite adhesive according to claim 7 or 8, characterized in that: The silane coupling agent includes at least one of γ-aminopropyltriethoxysilane, γ-glycidyloxypropyltrimethoxysilane and anilinomethyltrimethoxysilane; The plasticizer comprises at least one of diisononyl adipate, diisononyl phthalate, diisodecyl phthalate, trioctyl trimellitate and tri-2-ethylhexyl trimellitate; The photoinitiator includes a conjugated biphenyl organic compound, and the conjugated biphenyl organic compound includes at least one of 2-hydroxy-methylphenylpropane-1-one, 1-hydroxycyclohexylphenyl ketone, 2-methyl-1-(4-methylthiophenyl)-2-morpholinyl-1-propanone, benzoin dimethyl ether, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, ethyl dimethylaminobenzoate, benzophenone, 4-chlorobenzophenone, methyl o-benzoylbenzoate, 4-phenylbenzophenone, 2,4-diethylthiazolone, hexaaryldiimidazole and thioxanthone; The filler includes at least one of an inorganic filler and an organic filler; the inorganic filler includes at least one of glass, silica, talc, alumina, mica, ceramics, silicone rubber powder, calcium carbonate, aluminum nitride, carbon powder, kaolin, clay minerals and diatomaceous earth, and the particle size of the inorganic filler is 10 μm-50 μm; the organic filler includes at least one of polystyrene, polypropylene, polymethyl methacrylate, polybutylene and polypropylene carbonate, and the particle size of the organic filler is less than or equal to 50 μm; The insoluble particles include one or more of plastic balls, glass balls and zirconium oxide balls, and the particle size of the insoluble particles is 100 μm-120 μm.

10. A method for preparing the fluorine-containing composite adhesive according to any one of claims 1 to 9, characterized in that: include: The fluorine-containing composite adhesive is obtained by mixing 10-40 parts by weight of bisphenol epoxy resin, 30-45 parts by weight of resorcinol diglycidyl ether, 1-20 parts by weight of fluorine-containing epoxy resin and 0.5-5 parts by weight of cationic initiator.

11. An electrochromic device, characterized in that: The electrochromic device includes a first substrate and a second substrate stacked together, a first conductive layer is provided on the surface of the first substrate facing the second substrate, and a second conductive layer is provided on the surface of the second substrate facing the first substrate. An encapsulation layer is provided on the periphery of the surfaces facing each other of the first conductive layer and the second conductive layer, and the encapsulation layer is used to connect the first conductive layer and the second conductive layer to form a sealed accommodating space between the first conductive layer and the second conductive layer. The accommodating space is filled with an electrochromic electrolyte, and the encapsulation layer is made of the fluorine-containing composite adhesive described in any one of claims 1 to 9 or the fluorine-containing composite adhesive prepared by the preparation method described in claim 10.

12. An electronic device, characterized in that: Comprising the electrochromic device as claimed in claim 11.

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