A light valve and a method for improving the pressure resistance of a light valve

Abstract

The application provides a light valve, a manufacturing method of the light valve and a light control glass assembly. The light valve has excellent high-temperature compression resistance and can meet the requirements of a lamination process for manufacturing the light control glass assembly.

Description

Technical Field

[0001] The present invention relates to the field of electronic light-controlling materials, and in particular to a light valve with improved pressure resistance and a method for improving the pressure resistance of the light valve. Background Art

[0002] A light valve is an electronic light-control device consisting of a light-control layer placed between two layers of transparent conductive film. When an electric field is applied, the arrangement or state of the materials in the light-control layer changes, altering the device's light transmission characteristics, such as switching from low transmittance to high transmittance or vice versa. The electric field allows for rapid switching between on and off states. Depending on the light-control mechanism employed by the light-control layer, light valves can be categorized as suspended particle light valves, polymer dispersed liquid crystal light valves, and electrochemical reaction light valves.

[0003] Depending on the substrate of the light valve, it can be based on a plastic sheet such as PET, commonly known as a dimming film, or on glass, commonly known as dimming glass. The assembly formed by laminating the dimming film is generally known as a dimming glass assembly.

[0004] In practical applications, the film is often sandwiched between two pieces of glass and laminated under certain temperature and pressure to create a switchable glass assembly. However, the high temperature and pressure during the lamination process often significantly damage the color-changing properties of the film. This is primarily due to the poor compressive properties of the film's light-control layer at high temperatures, which significantly impacts the production of the switchable glass assembly.

[0005] Therefore, for the conventional dimming film, it is urgent to solve the problem of poor compressive performance of the light-controlling layer of the dimming film under high temperature conditions. Summary of the Invention

[0006] The present inventors unexpectedly discovered during long-term research that the problem of poor compressive performance of the light control layer under high temperature conditions can be effectively solved by using a polymer matrix containing a siloxane copolymer obtained by copolymerizing monomers of the following specific units:

[0007] (a) a silicon-containing non-crosslinking monomer, which may be provided in the form of a silicon-containing non-crosslinking monomer and / or an oligomer thereof,

[0008] (b) a silicon-containing crosslinkable monomer, and

[0009] (c) a silicon-containing monomer having a high-occupancy side chain, which has the following structural formula:

[0010] RX m -(CH2) n -SiR 1 x R2 y Formula (A)

[0011] in,

[0012] R 1 is a hydroxyl group or a group that can generate a hydroxyl group after hydrolysis, such as -Cl or C1-C3 alkoxy, especially R 1 selected from -OH, -Cl, -OCH3, -OCH2CH3, -OCH(CH3)2, -OCH2CH2OCH3, -OC(=O)-CH3, in particular selected from -OH, -Cl, -OCH3 and -OCH2CH3,

[0013] R 2 is C1-C3 alkyl, in particular methyl or ethyl,

[0014] x and y are integers from 0 to 3, and x+y=3, preferably x is 2 or 3,

[0015] X is selected from nitrogen, oxygen and sulfur,

[0016] m is 0 or 1, n is an integer from 0 to 10, preferably n is 0, 1, 2 or 3, more preferably 2 or 3,

[0017] R is a non-polymeric group, such as H or a chain or cyclic group R', wherein R' is selected from optionally substituted alkyl groups, cycloalkyl groups, aromatic ring groups, heterocyclic groups, cycloalkylalkyl groups, heterocyclic alkyl groups, aralkyl groups, carbonyl groups and carbamoyl groups, and the optional substituents are selected from hydroxyl groups, amino groups, mercapto groups, acidic groups, alkoxy groups, aryloxy groups, alkylthio groups, arylthio groups, alkylamino groups, arylamino groups, ester groups, halogen groups and epoxy groups, which may be further optionally substituted.

[0018] Accordingly, based on the above findings, in a first aspect, the present invention provides a light valve with improved pressure resistance, comprising:

[0019] a first transparent substrate,

[0020] a first transparent electrode formed on a first transparent substrate,

[0021] a second transparent substrate,

[0022] a second transparent electrode formed on a second transparent substrate, wherein the first transparent electrode and the second transparent electrode are arranged opposite to each other, and

[0023] A light-controlling layer is provided between the first transparent electrode and the second transparent electrode; the light-controlling layer comprises a polymer matrix;

[0024] The polymer matrix is ​​dispersed with suspension medium droplets, and solid light-controlling particles are distributed in the suspension medium droplets. The polymer matrix is ​​obtained by cross-linking and curing at least one siloxane copolymer, and the siloxane copolymer is obtained by copolymerizing monomers containing the following units:

[0025] (a) a silicon-containing non-crosslinking monomer, which may be provided in the form of a silicon-containing non-crosslinking monomer and / or an oligomer thereof,

[0026] (b) a silicon-containing crosslinkable monomer, and

[0027] (c) a silicon-containing monomer having a high-occupancy side chain, which has the following structural formula:

[0028] RX m -(CH2) n -SiR 1 x R 2 y Formula (A)

[0029] in,

[0030] R 1 is a hydroxyl group or a group that can generate a hydroxyl group after hydrolysis, such as -Cl or C1-C3 alkoxy, especially R 1 selected from -OH, -Cl, -OCH3, -OCH2CH3, -OCH(CH3)2, -OCH2CH2OCH3, -OC(=O)-CH3, in particular selected from -OH, -Cl, -OCH3 and -OCH2CH3,

[0031] R 2 is C1-C3 alkyl, in particular methyl or ethyl,

[0032] x and y are integers from 0 to 3, and x+y=3, preferably x is 2 or 3,

[0033] X is selected from nitrogen, oxygen and sulfur,

[0034] m is 0 or 1, n is an integer from 0 to 10, preferably n is 0, 1, 2 or 3, more preferably 2 or 3,

[0035] R is a non-polymeric group, such as H or a chain or cyclic group R', wherein R' is selected from optionally substituted alkyl groups, cycloalkyl groups, aromatic ring groups, heterocyclic groups, cycloalkylalkyl groups, heterocyclic alkyl groups, aralkyl groups, carbonyl groups and carbamoyl groups, and the optional substituents are selected from hydroxyl groups, amino groups, mercapto groups, acidic groups, alkoxy groups, aryloxy groups, alkylthio groups, arylthio groups, alkylamino groups, arylamino groups, ester groups, halogen groups and epoxy groups, which may be further optionally substituted.

[0036] The siloxane copolymer of the light valve of the present invention contains the unit (c), and the siloxane copolymer containing the unit (c) provides increased compressive strength compared to a siloxane copolymer not containing the unit (c).

[0037] In some preferred embodiments of the present invention, in the above formula (A), when RX m -When it is -OH, -SH or -NH2, RX m -(CH2) n - the total number of atoms excluding hydrogen is at least 4; when RX m -When it is not -OH, -SH or -NH2, RX m -(CH2) n - the total number of atoms excluding hydrogen is at least 6, and / or

[0038] Wherein in formula (A), when unit (c) comprises only one silicon-containing monomer having a high-occupancy side chain, RX m - is not -NH2, hydroxyl, glycidoxy, acryloyloxy, methacryloyloxy and acidic groups. In the present invention, the "acidic group" refers to a group that can donate a proton according to the Lewis acid-base theory, such as a carboxyl group, a sulfonic acid group, and a phosphoric acid group.

[0039] In some embodiments of the present invention, the polymer matrix is ​​formed by cross-linking and solidifying a polymer matrix precursor, wherein the polymer matrix precursor is synthesized from raw materials comprising:

[0040] (a) an oligomer of a silicon-containing non-crosslinked monomer;

[0041] (b) a silicon-containing cross-linkable monomer; and

[0042] (c) Silicon-containing monomers with high-occupancy side chains.

[0043] Preferably, the crosslinking and curing of the polymer matrix precursor used to form the polymer matrix occurs under thermal catalysis or radiation catalysis conditions. For example, a photoinitiator can be added to the polymer matrix precursor to induce a polymerization reaction by radiation. The photoinitiator can be those commonly used in the art, for example, 184 (CAS No. 947-19-3), ITX (CAS No. 5495-84-1 or 83846-86-0), 819 (CAS No. 162881-26-7), 1173 (CAS No. 7473-98-5), BDK (CAS No. 24650-42-8), BP (CAS No. 119-61-9), TPO (CAS No. 75980-60-8), 369 (CAS No. 119313-12-1), 907 (CAS No. 71868-10-5), including any one or any combination thereof.

[0044] In some embodiments of the present invention, in the light valve, wherein

[0045] The oligomer of the silicon-containing non-crosslinked monomer is silicone oil; and / or

[0046] The silicon-containing crosslinkable monomer is derived from a compound of formula (1):

[0047] Q-(CH2) m -Si(R n X 3-n ) Formula (1);

[0048] in,

[0049] Q is an acrylate polymerizable group;

[0050] R is an alkyl group;

[0051] X is a hydroxyl group, or a group that can generate a hydroxyl group after hydrolysis reaction;

[0052] m is a positive integer; n is 0, 1 or 2.

[0053] In some embodiments of the present invention, in the light valve, wherein

[0054] The oligomer of the silicon-containing non-crosslinked monomer is at least one of hydroxyl-terminated silicone oil and methoxy-terminated silicone oil; and / or

[0055] The silicon-containing crosslinkable monomer is derived from a compound of formula (1):

[0056] Q-(CH2) m -Si(R n X 3-n ) Formula (1);

[0057] in,

[0058] Q is a methacryloxy group or an acryloxy group;

[0059] R is a C1-C4 alkyl group;

[0060] X is at least one of -OH, -Cl, -OCH3, -OCH2CH3, -OCH(CH3)2, -OCH2CH2OCH3, and -OC(=O)-CH3;

[0061] m is an integer of 1 to 10, and n is 0 or 1.

[0062] In some embodiments of the present invention, the polymer matrix is ​​formed by cross-linking and solidifying a polymer matrix precursor, wherein the polymer matrix precursor is synthesized from raw materials comprising:

[0063] (a) an oligomer of a silicon-containing non-crosslinked monomer;

[0064] (b) a silicon-containing cross-linkable monomer; and

[0065] (c) Silicon-containing monomers with high-occupancy side chains.

[0066] Specifically, the silanol groups and / or groups capable of forming silanol groups on units (a), (b), and (c) can be subjected to a condensation reaction between silanol groups, or a condensation reaction between silanol groups and groups capable of forming silanol groups, or a condensation reaction between groups capable of forming silanol groups under certain conditions to obtain the polymer matrix precursor. Alternatively, the groups capable of forming silanol groups on units (a), (b), and (c) can be hydrolyzed to silanol groups under an acid catalyst, and then subjected to a condensation reaction between silanol groups under certain conditions to obtain a siloxane copolymer, and the polymer matrix precursor can be obtained from at least one siloxane copolymer.

[0067] More specifically, an organic solvent selected from at least one of hexane, heptane, octane, and toluene is used, and an organic tin catalyst selected from at least one of stannous 2-ethylhexanoate, stannous octoate, dibutyltin dilaurate, dibutyltin diacetate, and dioctyltin dilaurate is used. Units (a), (b), and (c) are added, and the mixture is reacted under reflux. After the reaction, unreacted raw materials, solvent, and low-boiling components are removed by separation extraction, vacuum distillation, or other means to obtain a siloxane copolymer. The polymer matrix precursor is obtained from the at least one siloxane copolymer.

[0068] In some embodiments of the present invention, the material forming the suspending medium droplets is selected from at least one of fluorocarbon organic compounds, phthalates, trimellitates, dodecylbenzene, polybutene oil, polyacrylates, polymethacrylates, epoxidized soybean oil, and epoxidized linseed oil. The phthalates may be dioctyl terephthalate, di(2-ethylhexyl) isophthalate, dibutyl phthalate, dioctyl phthalate, diisooctyl phthalate, and the like; the trimellitates may be methyl trimesic acid, trioctyl trimellitate, triisodecyl trimellitate, and the like.

[0069] In the present invention, the solid light-controlling particles can be any suitable light-controlling particles. Preferably, the solid light-controlling particles are selected from at least one of oxide nanorods, perovskite nanorods, and polyiodine compound nanorods.

[0070] In the present invention, the first transparent substrate and the second transparent substrate can be in any suitable form. In some embodiments of the present invention, the first transparent substrate and the second transparent substrate are glass plates. In other embodiments of the present invention, the first transparent substrate and the second transparent substrate are transparent plastic sheets.

[0071] In the present invention, the first transparent electrode and the second transparent electrode can be any suitable transparent electrode. In some embodiments of the present invention, the first transparent electrode and the second transparent electrode are each independently selected from an ITO conductive layer, an FZO conductive layer, an IZO conductive layer, a GZO conductive layer, an AZO conductive layer, a PEDOT conductive layer, a nano-Ag wire conductive layer, conductive graphene, and a nano-Cu wire conductive layer.

[0072] Preferably, in the light valve of the present invention, the first transparent electrode and / or the second transparent electrode may be covered with an insulating layer.

[0073] In a second aspect of the present invention, a switchable glass assembly is provided, comprising:

[0074] a first glass sheet and a second glass sheet, and

[0075] The light valve (dim-switching film) of the present invention as described above is disposed between the first glass plate and the second glass plate.

[0076] Preferably, in the switchable glass assembly of the present invention, a first interlayer is provided between the first glass plate and the light valve, and / or a second interlayer is provided between the second glass plate and the light valve.

[0077] In the present invention, there is no particular limitation on the types of the first glass plate and the second glass plate. They can be transparent glass used in conventional dimming glass assemblies well known to those skilled in the art. They can be ordinary glass such as inorganic glass or organic glass, or functional glass such as UV-blocking glass, IR-blocking glass, Low-E glass, tempered glass, or antibacterial glass.

[0078] In the present invention, the types of the first interlayer and the second interlayer are not particularly limited. They are conventional interlayers for dimming glass assemblies well known to those skilled in the art, and can be EVA films, TPU films, PVB films, or functional films such as UV-blocking EVA films, UV-blocking TPU films, and UV-blocking PVB films.

[0079] In the present invention, the method for manufacturing the dimming glass assembly is not particularly limited and can be a conventional laminating method for dimming glass assemblies in the art, such as laminating in a laminator, or laminating in an autoclave or laminating box / furnace.

[0080] In a third aspect of the present invention, a method for improving the pressure resistance of a light valve is provided, comprising:

[0081] Providing a light-control layer base emulsion;

[0082] coating the light control layer matrix emulsion on the first transparent electrode to form a light control layer wet film;

[0083] Covering the light control layer wet film with a second transparent electrode; and

[0084] The light control layer wet film is cross-linked and cured to obtain the light valve of the present invention.

[0085] in

[0086] The light-control layer matrix emulsion contains a polymer matrix precursor, in which suspension medium droplets are dispersed, and solid light-control particles are distributed in the suspension medium droplets. The polymer matrix precursor contains at least one siloxane copolymer, which is obtained by copolymerizing monomers containing the following units:

[0087] (a) a silicon-containing non-crosslinking monomer, which may be provided in the form of a silicon-containing non-crosslinking monomer and / or an oligomer thereof,

[0088] (b) a silicon-containing crosslinkable monomer, and

[0089] (c) a silicon-containing monomer having a high-occupancy side chain, which has the following structural formula:

[0090] RX m -(CH2) n -SiR 1 x R 2 y Formula (A)

[0091] in,

[0092] R 1 is a hydroxyl group or a group that can generate a hydroxyl group after hydrolysis, such as -Cl or C1-C3 alkoxy, especially R 1 selected from -OH, -Cl, -OCH3, -OCH2CH3, -OCH(CH3)2, -OCH2CH2OCH3, -OC(=O)-CH3, in particular selected from -OH, -Cl, -OCH3 and -OCH2CH3,

[0093] R 2 is C1-C3 alkyl, in particular methyl or ethyl,

[0094] x and y are integers from 0 to 3, and x+y=3, preferably x is 2 or 3,

[0095] X is selected from nitrogen, oxygen and sulfur,

[0096] m is 0 or 1, n is an integer from 0 to 10, preferably n is 0, 1, 2 or 3, more preferably 2 or 3,

[0097] R is a non-polymeric group, such as H or a chain or cyclic group R', wherein R' is selected from optionally substituted alkyl groups, cycloalkyl groups, aromatic ring groups, heterocyclic groups, cycloalkylalkyl groups, heterocyclic alkyl groups, aralkyl groups, carbonyl groups and carbamoyl groups, and the optional substituents are selected from hydroxyl groups, amino groups, mercapto groups, acidic groups, alkoxy groups, aryloxy groups, alkylthio groups, arylthio groups, alkylamino groups, arylamino groups, ester groups, halogen groups and epoxy groups, which may be further optionally substituted.

[0098] In some embodiments of the present invention involving the above-mentioned method for improving the compressive resistance of a light valve, the light-controlling layer matrix emulsion is obtained by the following steps:

[0099] providing a mixture containing a suspension medium of solid light-controlling particles;

[0100] providing a polymer matrix precursor; and

[0101] An initiator for initiating crosslinking and curing of the polymer matrix precursor, a mixture of the suspension medium containing solid light-controlling particles, and the polymer matrix precursor are mixed.

[0102] In the method for improving the pressure resistance of a light valve of the present invention, the light-controlling layer matrix emulsion and the polymer matrix precursor contained therein are in a liquid state. In the light valve of the present invention, the polymer matrix is ​​in a solid state after cross-linking and curing. BRIEF DESCRIPTION OF THE DRAWINGS

[0103] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are merely embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying any creative work.

[0104] Figure 1 Schematic diagram of the structure of a light-adjusting film provided in some embodiments of the present invention. Reference numeral 1 represents a transparent electrode, reference numeral 2 represents a light-control layer, reference numeral 3 represents a transparent substrate, reference numeral 21 represents a polymer matrix, reference numeral 22 represents a suspension medium droplet containing solid light-control particles, and reference numeral 23 represents solid light-control particles. DETAILED DESCRIPTION

[0105] the term

[0106] In the present invention, the following terms used have the meanings defined below.

[0107] Light valve:

[0108] A light valve is an electronic light-control device that consists of a light-control layer placed between two layers of transparent conductive film. When an electric field is applied, the arrangement or state of the material in the light-control layer changes, thereby changing the light transmittance of the device, such as from low transmittance to high transmittance, or from high transmittance to low transmittance.

[0109] Cross-linking:

[0110] Crosslinking refers to the polymerization reaction of the active groups on the side chains of the unit monomers in the polymer matrix precursor. The side chains refer to structures covalently linked to silicon atoms other than silanol groups and groups that can form silanol groups. In this article, crosslinking is sometimes also called crosslinking curing, which occurs under thermal catalysis or radiation catalysis conditions. For example, a photoinitiator is added to the polymer matrix precursor to induce polymerization through radiation. Silicon-containing non-crosslinking monomers:

[0111] The side chains of the monomer units (a) forming the polymer matrix precursor do not participate in the crosslinking reaction, and the side chains refer to structures covalently linked to silicon atoms other than silanol groups and groups that can form silanol groups. Silicon-containing crosslinkable monomers:

[0112] The monomer unit (b) forming the polymer matrix precursor has an active group on its side chain that can participate in the cross-linking reaction. The side chain refers to a structure covalently connected to the silicon atom except for the silanol group and the group that can form the silanol group.

[0113] Silicon-containing monomers with high-occupancy side chains:

[0114] The monomer unit (c) forming the polymer matrix precursor does not contain a group that can participate in the polymerization reaction on its side chain, and the side chain has large steric hindrance. The side chain refers to a structure covalently connected to the silicon atom other than the silanol group and the group that can form the silanol group.

[0115] Silicone oil:

[0116] A linear polysiloxane that remains liquid at room temperature.

[0117] Acrylate polymerizable groups:

[0118] It refers to a group containing a methacryloxy group or an acryloyloxy group.

[0119] alkyl:

[0120] Refers to a branched or straight-chain saturated aliphatic hydrocarbon group having a specified number of carbon atoms. For example, "C1-C3 alkyl" refers to an alkyl group having 1 to 3 carbon atoms. Examples of alkyl groups include, but are not limited to, methyl (Me), ethyl (Et), propyl (e.g., n-propyl and isopropyl), butyl (e.g., n-butyl, isobutyl, tert-butyl), and pentyl (e.g., n-pentyl, isopentyl, neopentyl).

[0121] The present invention provides a light valve with improved compressive resistance, wherein the polymer matrix precursor is composed of at least one siloxane copolymer. When the polymer matrix precursor is composed of only one siloxane copolymer, the two terms siloxane copolymer and polymer matrix precursor are equivalent.

[0122] The present invention provides a light valve with improved compressive resistance. By using a polymer matrix precursor obtained by copolymerizing monomers containing specific units and then crosslinking to form a polymer matrix, the present invention effectively addresses the problem of poor compressive resistance of the light-control layer at high temperatures. Specifically, the present invention utilizes unit (c) of the following structural formula (A), i.e., a silicon-containing monomer with a high-occupancy side chain, to effectively achieve improved compressive resistance compared to a light valve without unit (c):

[0123] RX m -(CH2) n -SiR 1 x R 2 y Formula (A)

[0124] See also Figure 1 The polymer matrix precursor contains cross-linkable and curable functional groups, which undergo a cross-linking reaction and cure to form a polymer matrix 21. The suspending medium is dispersed in the polymer matrix in the form of droplets, and the droplets formed are called suspending medium droplets 22.

[0125] In order to better illustrate the present invention, the following specific embodiments are provided, including various preparation embodiments (including the preparation of solid light-controlling particles, the preparation of liquid suspension media, the preparation of polymer matrix precursors, and the preparation of dimming films) and compression resistance test embodiments.

[0126] Example 1 Preparation of solid light-controlling particles 23

[0127] To a 250 mL three-necked round-bottom glass flask, add 30 g of an isoamyl acetate solution containing 21.2 wt% nitrocellulose (model SS 1 / 4sec), 6 g of I2, 70 g of isoamyl acetate, and 4 g of anhydrous CaI2, and heat to 42°C. After the I2 is dissolved, add 6 g of anhydrous methanol, 0.8 g of distilled water, and 4 g of 2,5-pyrazinedicarboxylic acid dihydrate to the three-necked round-bottom glass flask, heat and stir at 42°C for 4 hours, and then cool naturally. The resulting reaction solution is centrifuged at 1350 g for 0.5 h to remove large particles of product, and then the supernatant is centrifuged at 18,000 g for 5 h. The supernatant is discarded to obtain solid light-controlling particles 23. The solid light-controlling particles 23 are fully dispersed with 250 ml of isoamyl acetate.

[0128] Example 2 Preparation of liquid suspension medium

[0129] 24.4 g of dodecyl methacrylate, 2.0 g of hydroxyethyl methacrylate, 2.3 g of 1-hexanethiol, and 20 mL of toluene were added to a 250 mL three-necked round-bottom glass flask. A mechanical stirrer was installed in the middle of the flask, with a condenser connected to one side and a thermometer placed on the other side, all connected to argon. Before heating, argon was passed through the flask for approximately 10 minutes to completely displace the air in the flask. The flask was then heated to 60°C. At this temperature, a 10 mL toluene solution containing 0.20 g of azobisisobutyronitrile was added to the flask. The reaction temperature was maintained at 60°C for 21 hours, then the temperature was raised and the reaction solution was refluxed for 3 hours. The reaction was stopped. The toluene and unreacted starting materials were then removed using a rotary evaporator at 100°C for 3 hours to obtain a liquid suspension medium.

[0130] 40 g of the obtained suspension medium was added to a 250 ml round-bottom glass flask, and the isoamyl acetate dispersion of the solid light-controlling particles 23 prepared in Example 1 was added in batches. The isoamyl acetate was removed by a rotary evaporator. Finally, the rotary evaporator was used to continue processing at 80°C for 3 hours to obtain a mixture of a liquid suspension medium containing solid light-controlling particles 23.

[0131] Example 3 Preparation of Siloxane Copolymer

[0132] To a 500 mL three-necked round-bottom glass flask, add (a) a silicon-containing, non-crosslinked oligomer: 54 g of hydroxyl-terminated dimethyldiphenylpolysiloxane and 190 mL of n-heptane. A water separator connected to a condenser was attached to one side of the flask, a mechanical stirrer was installed in the middle, and a thermometer was placed on the other side. The reaction solution in the flask was heated to reflux for 30 minutes, followed by the addition of a solution of 0.13 g of stannous octoate dissolved in 10 mL of n-heptane. A mixture of (b) a silicon-containing, crosslinkable monomer: 3 g of hydrolyzed 3-acryloyloxypropylmethyldimethoxysilane, and (c) a silicon-containing monomer with a high-occupancy side chain: 1.8 g of hydrolyzed 3-glycidoxypropylmethyldimethoxysilane was then added dropwise over approximately 5 minutes. The reaction was then allowed to proceed under reflux for 2 hours, after which 30 mL of trimethylmethoxysilane was immediately added as a terminator. The reaction was terminated for 2 hours, followed by rapid cooling to room temperature. Mix 50 mL of ethanol and the cooled reaction solution in a 1 L beaker, then rinse the reaction bottle with 30 mL of heptane and pour it into the beaker. After mixing evenly, add 200 mL of methanol and stir for 15 minutes. Pour the resulting mixture into a 1 L separatory funnel and let it stand for several hours until layers appear. Take out the lower layer and then treat it with a rotary evaporator at 70 ° C for 3 hours to remove low-boiling substances, and finally obtain Siloxane copolymer .

[0133] Hydrolysis reaction: Connect a condenser to one side of a three-necked round-bottom glass flask, install a mechanical stirrer in the middle, and place a thermometer on the other side. To a 250 mL three-necked round-bottom glass flask, add 0.1 g of acetic acid, 5.5 g of water, 44.5 g of 3-acryloyloxypropylmethyldimethoxysilane or 44.5 g of 3-glycidoxypropylmethyldimethoxysilane, and 35 mL of anhydrous ethanol. Control the hydrolysis temperature to 65°C and allow the reaction to proceed for 5 hours. After the reaction, remove the solvent, excess water, and acid using a rotary evaporator to obtain the hydrolyzed product.

[0134] Example 4 Preparation of Siloxane Copolymer

[0135] The same as Example 3, except that the silicon-containing monomer with a high-occupancy side chain in unit (c)) is replaced by 3-piperazinylpropylmethyldimethoxysilane: hydrolyzed 3-glycidyloxypropylmethyldimethoxysilane.

[0136] Example 5 Preparation of Siloxane Copolymer

[0137] The same as Example 3, except that the silicon-containing monomer with a high-occupancy side chain in unit (c): hydrolyzed 3-glycidyloxypropylmethyldimethoxysilane is replaced by isooctyltrimethoxysilane.

[0138] Example 6 Preparation of Siloxane Copolymer

[0139] The same as Example 3, except that the silicon-containing monomer with a non-crosslinked side chain in unit (c): hydrolyzed 3-glycidyloxypropylmethyldimethoxysilane is replaced by 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane.

[0140] Example 7 Preparation of Siloxane Copolymer

[0141] Same as Example 3, except that the silicon-containing crosslinkable monomer in unit (b): hydrolyzed 3-acryloxypropylmethyldimethoxysilane is replaced by 3-methacryloxypropyltrimethoxysilane;

[0142] At the same time, the silicon-containing monomer with a high-occupancy side chain in unit (c): hydrolyzed 3-glycidyloxypropylmethyldimethoxysilane is replaced with 3-(N-cyclohexylamino)propyltrimethoxysilane.

[0143] Example 8 Preparation of Siloxane Copolymer

[0144] The same as Example 7, except that the silicon-containing monomer with a high-occupancy side chain in unit (c): 3-(N-cyclohexylamino)propyltrimethoxysilane is replaced by 3-mercaptopropyltrimethoxysilane.

[0145] Example 9 Preparation of Siloxane Copolymer

[0146] The same as Example 7, except that the silicon-containing monomer with a high-occupancy side chain in unit (c): 3-(N-cyclohexylamino)propyltrimethoxysilane is replaced by 3-ureapropyltriethoxysilane.

[0147] Example 10 Preparation of siloxane copolymer

[0148] The same as Example 7, except that the silicon-containing monomer with a high-occupancy side chain in unit (c): 3-(N-cyclohexylamino)propyltrimethoxysilane is replaced by cyclohexyltrimethoxysilane.

[0149] Example 11 Preparation of Siloxane Copolymer

[0150] The same as Example 7, except that the silicon-containing monomer with a high-occupancy side chain in unit (c): 3-(N-cyclohexylamino)propyltrimethoxysilane is replaced by 1H,1H,2H,2H-perfluorooctyltrimethoxysilane.

[0151] Example 12 Preparation of Siloxane Copolymer

[0152] The same as Example 7, except that the silicon-containing monomer with a high-occupancy side chain in unit (c): 3-(N-cyclohexylamino)propyltrimethoxysilane is replaced by benzoyloxypropyltrimethoxysilane.

[0153] Example 13 Preparation of Siloxane Copolymer

[0154] The same as Example 7, except that the silicon-containing monomer with a high-occupancy side chain in unit (c): 3-(N-cyclohexylamino)propyltrimethoxysilane is replaced by methyl (trimethoxysilyl)propionate.

[0155] Example 14 Preparation of Siloxane Copolymer

[0156] The same as Example 7, except that the silicon-containing monomer with a high-occupancy side chain in unit (c): 3-(N-cyclohexylamino)propyltrimethoxysilane is replaced by 9-anthryl(trimethoxy)silane.

[0157] Example 15 Preparation of Siloxane Copolymer

[0158] The same as Example 7, except that the silicon-containing monomer with a high-occupancy side chain in unit (c): 3-(N-cyclohexylamino)propyltrimethoxysilane is replaced by trimethoxysilylpropoxypolyethylene oxide methyl ether.

[0159] Example 16 Preparation of Siloxane Copolymer

[0160] The same as Example 7, except that the silicon-containing monomer with a high-occupancy side chain in unit (c): 3-(N-cyclohexylamino)propyltrimethoxysilane is replaced by 3-(phenylamino)propyltrimethoxysilane.

[0161] Example 17 Preparation and Compression Test of the Smart Film

[0162] The initiator for initiating cross-linking and curing of the polymer matrix precursor, the suspension medium containing the solid light-controlling particles 23 and the polymer matrix precursor are mixed uniformly, and the resulting mixture is called a light-controlling layer matrix emulsion.

[0163] The initiator for initiating cross-linking and curing of the polymer matrix precursor is preferably a photoinitiator, specifically photoinitiator 819 in the embodiment of the present invention. The type of photoinitiator can be selected according to actual needs in the present invention without any special limitation. The initiator for initiating cross-linking and curing of the polymer matrix precursor is preferably at least one of 184 (CAS No. 947-19-3), ITX (CAS No. 5495-84-1 or 83846-86-0), 819 (CAS No. 162881-26-7), 1173 (CAS No. 7473-98-5), BDK (CAS No. 24650-42-8), BP (CAS No. 119-61-9), TPO (CAS No. 75980-60-8), 369 (CAS No. 119313-12-1), and 907 (CAS No. 71868-10-5). The amount (mass percentage) of the photoinitiator used is preferably 0.05% to 1% of the polymer matrix precursor, more preferably 0.1% to 0.6%, and even more preferably 0.2% to 0.5%.

[0164] 0.03 g of photoinitiator 819, 3.0 g of the liquid suspension medium containing solid light-controlling particles 23 prepared in Example 2 and 3.0 g of the liquid suspension medium prepared in Example 3 were mixed. Siloxane copolymer 7.0 g were mixed evenly to obtain a light-control layer matrix emulsion.

[0165] The light-control layer matrix emulsion was coated onto an ITO / PET transparent conductive film using a doctor blade automatic coating machine (MSK-AFA-III, MTI Corporation) to a thickness of 80 μm. Another layer of ITO / PET transparent conductive film was then applied to the wet film containing the light-control layer matrix emulsion to obtain a wet film containing the light-control layer. The film was then cured for 1 minute using an Aventk X200-150 UV curing machine with a UV power of 700 W / m² under a nitrogen atmosphere. 2 , and the dimming film is obtained.

[0166] In this embodiment, a transparent conductive film (transparent electrode) is formed on a plastic sheet substrate.

[0167] The polymer matrix precursor is cross-linked and solidified to form a polymer matrix.

[0168] In this application, the relative change rate ΔT of the light valve transmittance T is used to characterize the pressure resistance of the light valve.

[0169] Relative change rate of ΔT = [(Ton before compression test - Toff before compression test) - (Ton after compression test - Toff after compression test)] / (Ton before compression test - Toff before compression test) * 100%, where Ton refers to the transmittance of the light valve when it is powered on, and Toff refers to the transmittance of the light valve when it is not powered on. The electric field strength measured by Ton before the compression test is the same as that measured by Ton after the compression test.

[0170] Obviously, the smaller the relative change rate of ΔT is, the better the pressure resistance of the light valve is.

[0171] The light transmittance of the dimming film was measured using an LS116 light transmittance meter (Shenzhen Linshang Technology Co., Ltd.). When no voltage was applied (off state), the film's light transmittance, Toff, was 0.5%. When 60 Hz, 220 V AC power was applied (on state), the film's total light transmittance, Ton, was 59.5%.

[0172] Compression test:

[0173] The dimming film was sandwiched between two sheets of glass and subjected to a compression test in a laminator. The test conditions were: 110°C, vacuum for 10 minutes, gradual pressure increase to 350kPa, a 30-minute delay, and then cooling to room temperature. The film's transmittance was then measured. When no voltage was applied (off state), the film's transmittance, Toff, was 0.5%. When 60Hz, 220V AC was applied (on state), the film's total light transmittance, Ton, was 56.1%.

[0174] See Table 1 for specific results.

[0175] Example 18 Preparation and Compression Test of the Shifting Film

[0176] The same as Example 17, except that the siloxane copolymer prepared in Example 3 was replaced by the siloxane copolymer prepared in Example 4. The compression test conditions were: temperature 110° C., vacuuming for 10 minutes, gradually increasing the pressure to 300 kPa, and delaying for 30 minutes.

[0177] Example 19 Preparation and Compression Test of the Shifting Film

[0178] The same as Example 17, except that the siloxane copolymer prepared in Example 3 was replaced by the siloxane copolymer prepared in Example 5. The compression test conditions were: temperature 120° C., vacuuming for 10 minutes, gradually increasing the pressure to 300 kPa, and delaying for 30 minutes.

[0179] Example 20 Preparation and Compression Test of the Shifting Film

[0180] The same as Example 17, except that the siloxane copolymer prepared in Example 3 was replaced by the siloxane copolymer prepared in Example 6. The compression test conditions were: temperature 115° C., vacuuming for 10 minutes, gradually increasing the pressure to 300 kPa, and delaying for 30 minutes.

[0181] Example 21 Preparation and Compression Test of the Shifting Film

[0182] The same as Example 17, except that the siloxane copolymer prepared in Example 3 was replaced by the siloxane copolymer prepared in Example 7. The laminator was replaced by an autoclave, and the compression test conditions were a temperature of 125° C., a gradual increase in pressure to 350 kPa, and a delay of 30 minutes.

[0183] Example 22 Preparation and Compression Test of the Shifting Film

[0184] Same as Example 21, except that the siloxane copolymer prepared in Example 7 is replaced by the siloxane copolymer prepared in Example 8.

[0185] Example 23 Preparation and Compression Test of the Shifting Film

[0186] Same as Example 21, except that the siloxane copolymer prepared in Example 7 is replaced by the siloxane copolymer prepared in Example 9.

[0187] Example 24 Preparation and Compression Test of the Shifting Film

[0188] Same as Example 21, except that the siloxane copolymer prepared in Example 7 is replaced by the siloxane copolymer prepared in Example 10.

[0189] Example 25 Preparation and Compression Test of the Shifting Film

[0190] Same as Example 21, except that the siloxane copolymer prepared in Example 7 is replaced by the siloxane copolymer prepared in Example 11.

[0191] Example 26 Preparation and Compression Test of the Smart Film

[0192] Same as Example 21, except that the siloxane copolymer prepared in Example 7 is replaced by the siloxane copolymer prepared in Example 12.

[0193] Example 27 Preparation and Compression Test of the Smart Film

[0194] Same as Example 21, except that the siloxane copolymer prepared in Example 7 is replaced by the siloxane copolymer prepared in Example 13.

[0195] Example 28 Preparation and Compression Test of the Shifting Film

[0196] Same as Example 21, except that the siloxane copolymer prepared in Example 7 is replaced by the siloxane copolymer prepared in Example 14.

[0197] Example 29 Preparation and Compression Test of the Shifting Film

[0198] Same as Example 21, except that the siloxane copolymer prepared in Example 7 is replaced by the siloxane copolymer prepared in Example 15.

[0199] Example 30 Preparation and Compression Test of the Shifting Film

[0200] Same as Example 21, except that the siloxane copolymer prepared in Example 7 is replaced by the siloxane copolymer prepared in Example 16.

[0201] Comparative Example 1 Preparation without (c) Siloxane copolymer

[0202] The same as Example 3, except that (c) the silicon-containing monomer having a high-occupancy side chain is not added.

[0203] Comparative Example 2 Preparation without (c) Siloxane copolymer

[0204] Same as Example 7, except that (c) the silicon-containing monomer having a high-occupancy side chain is not added.

[0205] Comparative Example 3 Preparation and Compression Test of Smart Film

[0206] The same as Example 17, except that the siloxane copolymer prepared in Comparative Example 1 was used instead of the siloxane copolymer prepared in Example 3, and no pressure was applied, only vacuum was applied.

[0207] Comparative Example 4 Preparation and Compression Test of the DIY Film

[0208] Same as Example 17, except that the siloxane copolymer prepared in Comparative Example 1 was used instead of the siloxane copolymer prepared in Example 3.

[0209] Comparative Example 5 Preparation and Compression Test of the Smart Film

[0210] Same as Example 21, except that the siloxane copolymer prepared in Comparative Example 2 is used instead of the siloxane copolymer prepared in Example 7.

[0211] The results of Examples 17-30 and Comparative Examples 3-5 are shown in Table 1 below.

[0212] Table 1

[0213]

[0214]

[0215] A comparison of Comparative Examples 3-5 with Examples 17-30 in Table 1 demonstrates that the addition of (c) at least one silicon-containing monomer with a high-occupancy side chain significantly improves the compressive strength of the light-control layer. The relative change in ΔT is significantly lower than that of a dimming film prepared using a polymer matrix precursor without (c) at least one silicon-containing monomer with a high-occupancy side chain. This solution fully meets the laminating process requirements for subsequent dimming glass assembly fabrication using a laminator or autoclave.

[0216] The present invention has been described above using a light valve with a transparent plastic sheet as a substrate, i.e., a dimming film, as an example. Obviously, the concepts of the present invention are also fully applicable to light valves with a glass substrate, i.e., dimming glass. The above examples are merely intended to facilitate understanding of the method and core concepts of the present invention. Various modifications to these examples will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention is not limited to the embodiments shown herein, but is intended to be embodied in the widest possible scope consistent with the principles and novel features disclosed herein.

Claims

1. A light valve having increased compressive strength, comprising: a first transparent substrate, a first transparent electrode formed on a first transparent substrate, a second transparent substrate, a second transparent electrode formed on a second transparent substrate, wherein the first transparent electrode and the second transparent electrode are arranged opposite to each other, and A light-controlling layer is provided between the first transparent electrode and the second transparent electrode; the light-controlling layer comprises a polymer matrix; The polymer matrix is ​​dispersed with suspension medium droplets, and solid light-controlling particles are distributed in the suspension medium droplets. The polymer matrix is ​​obtained by cross-linking and curing at least one siloxane copolymer, and the siloxane copolymer is obtained by copolymerizing monomers containing the following units: (a) a silicon-containing non-crosslinking monomer, which is provided in the form of a silicon-containing non-crosslinking monomer and / or an oligomer thereof, (b) a silicon-containing crosslinkable monomer, and (c) a silicon-containing monomer having a high-occupancy side chain, which has the following structural formula: RX m -(CH2) n -SiR 1 x R 2 y Formula (A) in, R 1 It is a hydroxyl group or a group that can generate a hydroxyl group after hydrolysis reaction, R 2 is a C1-C3 alkyl group, x and y are integers from 0 to 3, and x+y=3, X is selected from nitrogen, oxygen and sulfur, m is 0 or 1, n is an integer from 0 to 10, R is a non-polymeric group selected from H, a chain group R' and a cyclic group R', wherein R' is selected from optionally substituted alkyl groups, cycloalkyl groups, aromatic ring groups, heterocyclic groups, cycloalkylalkyl groups, aralkyl groups, carbonyl groups and carbamoyl groups, and the optional substituents are selected from amino groups, mercapto groups, alkoxy groups, aryloxy groups, alkylthio groups, arylthio groups, alkylamino groups, arylamino groups, ester groups and halogen groups.

2. The light valve according to claim 1, wherein in formula (A), when RX m -When it is -OH, -SH or -NH2, RX m -(CH2) n - the total number of atoms excluding hydrogen is at least 4; when RX m -When it is not -OH, -SH or -NH2, RX m -(CH2) n - the total number of atoms excluding hydrogen is at least 6, and / or Wherein in formula (A), when unit (c) comprises only one silicon-containing monomer having a high-occupancy side chain, RX m - is not -NH2, hydroxyl, glycidoxy, acryloyloxy, methacryloyloxy or acidic group.

3. The light valve according to claim 1, wherein the polymer matrix is ​​formed by cross-linking and curing a polymer matrix precursor, wherein the polymer matrix precursor is synthesized from raw materials comprising: (a) an oligomer of a silicon-containing non-crosslinked monomer; (b) a silicon-containing crosslinkable monomer; and (c) Silicon-containing monomers with high-occupancy side chains.

4. The light valve according to claim 3, wherein the cross-linking curing occurs under thermal catalysis or radiation catalysis conditions. 5 . The light valve according to claim 4 , wherein the photoinitiator is selected from at least one of 184, ITX, 819, 1173, BDK, BP, TPO, 369, and 907.

6. The light valve according to any one of claims 1 to 5, wherein: The oligomer of the silicon-containing non-crosslinked monomer is silicone oil; and / or The silicon-containing crosslinkable monomer is derived from a compound of formula (1): Q-(CH2) m -Si(R n X 3-n ) formula (1); in, Q is an acrylate polymerizable group; R is an alkyl group; X is a hydroxyl group, or a group that can generate a hydroxyl group after hydrolysis reaction; m is a positive integer; n is 0, 1 or 2.

7. The light valve according to any one of claims 1 to 5, wherein: The oligomer of the silicon-containing non-crosslinked monomer is at least one of hydroxyl-terminated silicone oil and methoxy-terminated silicone oil; and / or The silicon-containing crosslinkable monomer is derived from a compound of formula (1): Q-(CH2) m -Si(R n X 3-n ) formula (1); in, Q is a methacryloxy group or an acryloxy group; R is a C1-C4 alkyl group; X is at least one of -OH, -Cl, -OCH3, -OCH2CH3, -OCH(CH3)2, -OCH2CH2OCH3, and -OC(=O)-CH3; m is an integer of 1 to 10, and n is 0 or 1.

8. The light valve according to any one of claims 1 to 5, wherein: The material forming the suspension medium droplets is selected from at least one of fluorocarbon organic compounds, phthalates, trimellitates, dodecylbenzene, polybutene oil, polyacrylates, polymethacrylates, epoxidized soybean oil, and epoxidized linseed oil.

9. The light valve according to any one of claims 1 to 5, wherein: The solid light-controlling particles are selected from at least one of oxide nanorods, perovskite nanorods, and polyiodine compound nanorods.

10. The light valve according to any one of claims 1 to 5, wherein the first transparent substrate and the second transparent substrate are glass plates.

11. The light valve according to any one of claims 1 to 5, wherein the first transparent substrate and the second transparent substrate are transparent plastic sheets.

12. The light valve according to any one of claims 1 to 5, wherein the first transparent electrode and the second transparent electrode are each independently selected from an ITO conductive layer, an FZO conductive layer, an IZO conductive layer, a GZO conductive layer, an AZO conductive layer, a PEDOT conductive layer, a nano-Ag wire conductive layer, conductive graphene, and a nano-Cu wire conductive layer. 13 . The light valve according to claim 1 , wherein the first transparent electrode and / or the second transparent electrode is covered with an insulating layer.

14. A dimming glass assembly comprising a first glass sheet and a second glass sheet, and The light valve according to any one of claims 1 to 13, arranged between the first glass plate and the second glass plate. 15 . The switchable glass assembly according to claim 14 , wherein a first interlayer is provided between the first glass plate and the light valve, and / or a second interlayer is provided between the second glass plate and the light valve.

16. A method for improving the compressive performance of a light valve, comprising: Providing a light-control layer base emulsion; coating the light control layer matrix emulsion on the first transparent electrode to form a light control layer wet film; Covering the light control layer wet film with a second transparent electrode; and The light control layer wet film is cross-linked and cured to obtain the light valve according to any one of claims 1 to 13, in The light-control layer matrix emulsion contains a polymer matrix precursor, in which suspension medium droplets are dispersed, and solid light-control particles are distributed in the suspension medium droplets. The polymer matrix precursor contains at least one siloxane copolymer, which is obtained by copolymerizing monomers containing the following units: (a) a silicon-containing non-crosslinking monomer, which is provided in the form of a silicon-containing non-crosslinking monomer and / or an oligomer thereof, (b) a silicon-containing crosslinkable monomer, and (c) a silicon-containing monomer having a high-occupancy side chain, which has the following structural formula: RX m -(CH2) n -SiR 1 x R 2 y Formula (A) in, R 1 It is a hydroxyl group or a group that can generate a hydroxyl group after hydrolysis reaction, R 2 is a C1-C3 alkyl group, x and y are integers from 0 to 3, and x+y=3, X is selected from nitrogen, oxygen and sulfur, m is 0 or 1, n is an integer from 0 to 10, R is a non-polymeric group selected from H, a chain group R' and a cyclic group R', wherein R' is selected from optionally substituted alkyl groups, cycloalkyl groups, aromatic ring groups, heterocyclic groups, cycloalkylalkyl groups, aralkyl groups, carbonyl groups and carbamoyl groups, and the optional substituents are selected from amino groups, mercapto groups, alkoxy groups, aryloxy groups, alkylthio groups, arylthio groups, alkylamino groups, arylamino groups, ester groups and halogen groups.

17. The method according to claim 16, wherein the light control layer base emulsion is obtained by the steps of: providing a mixture containing a suspension medium of solid light-controlling particles; providing a polymer matrix precursor; and An initiator for initiating crosslinking and curing of the polymer matrix precursor, a mixture of the suspension medium containing solid light-controlling particles, and the polymer matrix precursor are mixed.

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