Flexible composite material and preparation method and application thereof

Abstract

The present invention provides a flexible composite material, and a preparation method and an application thereof, belonging to the technical field of functional materials. The flexible composite material provided by the present invention comprises a fiber cloth and a strontium titanate nano-micro material compounded in the fiber cloth; the raw materials for preparing the strontium titanate nano-micro material comprise a matrix material and a dispersant, the mass of the dispersant is 0.05-0.2% of the mass of the matrix material; the matrix material comprises the following raw materials in mass fractions: 50-90 parts of a powdered resin; 10-50 parts of a curing agent; 0-20 parts of an antioxidant additive; 0.05-0.2 parts of a catalyst; 0-10 parts of a surface adjuster; 0-20 parts of a light stabilizer; 0.05-5 parts of a strontium titanate nano-additive, and the strontium titanate nano-additive is a compound of octahedral strontium titanate, hexahedral strontium titanate and irregular strontium titanate in a specific ratio. The flexible composite material provided by the present invention has excellent weather resistance.

Description

A flexible composite material and its preparation method and application

[0001] This application claims priority to the Chinese patent application filed with the Patent Office of China on June 29, 2023, with application number CN202310778172.0 and invention name “A flexible composite material, its preparation method and application”, the entire contents of which are incorporated by reference into this application. Technical Field

[0002] The present invention relates to the technical field of functional materials, and in particular to a flexible composite material and a preparation method and application thereof. Background Art

[0003] Traditional photovoltaic modules are composed of TPT backsheets, EVA films, solar cells, glass panels, frames, and more. Traditional photovoltaic modules are rigid, not easily deformed, and are relatively heavy, making them unsuitable for applications requiring flexibility or lightweight. Flexible solar panels are an emerging technology product in the global solar industry. Specifically, they replace the glass panels and even the TPT backsheets in traditional photovoltaic modules with flexible composite materials, providing protection and support for the solar cells. Flexible solar panels are flexible and easy to bend, allowing them to bend freely to the shape of the roof when the average roof slope is less than 60° and the bending radius is greater than 13m. Furthermore, flexible solar panels are lightweight, and their installation will not place excessive loads on the roof, nor will the main roof structure undergo significant changes. However, the weather resistance of flexible composite materials in existing technologies still needs to be improved.

[0004] Summary of the Invention

[0005] The purpose of the present invention is to provide a flexible composite material and a preparation method and application thereof. The flexible composite material provided by the present invention has excellent weather resistance.

[0006] In order to achieve the above-mentioned object of the invention, the present invention provides the following technical solutions:

[0007] The present invention provides a flexible composite material, comprising a fiber cloth and a strontium titanate nanomaterial composited in the fiber cloth;

[0008] The raw materials for preparing the strontium titanate nanomaterial include a base material and a dispersant, wherein the mass of the dispersant is 0.05-0.2% of the mass of the base material; the base material includes the following raw materials in parts by mass: 50-90 parts of powdered resin; 10-50 parts of curing agent; 0-20 parts of antioxidant; 0.05-0.2 parts of catalyst; 0-10 parts of surface adjuster; 0-20 parts of light stabilizer; 0.05-5 parts of strontium titanate nano-additive, wherein the strontium titanate nano-additive is a mixture of octahedral strontium titanate, hexahedral strontium titanate and irregular strontium titanate, and the mass ratio of the octahedral strontium titanate, hexahedral strontium titanate and irregular strontium titanate is 3-4:4-6:1-2.

[0009] Preferably, the fiber cloth is glass fiber cloth.

[0010] Preferably, the fiber cloth has a gram weight of 100 to 400 g / m 2 .

[0011] Preferably, the particle size of the strontium titanate nano-additive is 50 to 300 nm.

[0012] Preferably, the particle size of the octahedral strontium titanate is 100 to 200 nm; the particle size of the hexahedral strontium titanate is 100 to 200 nm; and the particle size of the irregular strontium titanate is 50 to 100 nm.

[0013] Preferably, the powder resin includes one or more of acrylic resin, polyurethane resin and polyester resin.

[0014] Preferably, the acrylic resin is an epoxy acrylic resin.

[0015] Preferably, the curing agent includes one or more of dodecanedicarboxylic acid, triglycidyl isocyanurate and isocyanate.

[0016] Preferably, the antioxidant auxiliary agent includes one or more of β-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate, benzofuranone derivatives and thioester antioxidants.

[0017] Preferably, the catalyst comprises tetrabutylammonium bromide, dibutyltin dilaurate or 2-propylimidazole.

[0018] Preferably, the surface conditioning agent comprises benzoin.

[0019] Preferably, the particle size of the matrix material is 30 to 150 μm.

[0020] Preferably, the particle size of the dispersant is 2 to 8 μm.

[0021] Preferably, the dispersant includes one or more of alumina, fumed silica and glass microspheres.

[0022] Preferably, the content of strontium titanate nanomaterials in the flexible composite material is 50-80 wt%.

[0023] The present invention provides a method for preparing the flexible composite material described in the above technical solution, comprising the following steps:

[0024] The fiber cloth is impregnated with molten strontium titanate nanomaterials and then solidified to obtain a flexible composite material.

[0025] Preferably, the method of impregnating the fiber cloth with molten strontium titanate nanomaterial comprises the following steps:

[0026] The strontium titanate nano-micro material is laid on the surface of the fiber cloth, and is heated by a laminating device or a rolling device to melt the strontium titanate nano-micro material and infiltrate the fiber cloth.

[0027] Preferably, the method of impregnating the fiber cloth with molten strontium titanate nanomaterial comprises the following steps:

[0028] The strontium titanate nanomaterial is extruded to obtain a resin film, the resin film is laminated and compounded on the surface of the fiber cloth, and heated by a laminating device or a rolling device to melt the resin film and infiltrate the fiber cloth.

[0029] Preferably, the curing temperature is 130-200° C., the pressure is 1-20 MPa, and the curing time is 10-90 min.

[0030] The present invention provides the use of the flexible composite material described in the above technical solution or the flexible composite material prepared by the preparation method described in the above technical solution as a photovoltaic module packaging material.

[0031] Preferably, the packaging material is the packaging material of the front panel or the packaging material of the back panel of the photovoltaic module.

[0032] Beneficial effects: The flexible composite material provided by the present invention is compounded with strontium titanate nanomaterials in the fiber cloth, and a strontium titanate nano-additive is added to the matrix material of the strontium titanate nanomaterials, and the strontium titanate nano-additive is obtained by compounding strontium titanate of a specific morphology according to a specific ratio, which can make the flexible composite material have excellent weather resistance; in addition, the flexible composite material provided by the present invention also has the characteristics of light weight, high strength, high light transmittance and good water barrier properties. DETAILED DESCRIPTION

[0033] The present invention provides a flexible composite material, comprising a fiber cloth and a strontium titanate nanomaterial composited in the fiber cloth;

[0034] The raw materials for preparing the strontium titanate nanomaterial include a base material and a dispersant, wherein the mass of the dispersant is 0.05-0.2% of the mass of the base material; the base material includes the following raw materials in parts by mass: 50-90 parts of powdered resin; 10-50 parts of curing agent; 0-20 parts of antioxidant; 0.05-0.2 parts of catalyst; 0-10 parts of surface adjuster; 0-20 parts of light stabilizer; 0.05-5 parts of strontium titanate nano-additive, wherein the strontium titanate nano-additive is a mixture of octahedral strontium titanate, hexahedral strontium titanate and irregular strontium titanate, and the mass ratio of the octahedral strontium titanate, hexahedral strontium titanate and irregular strontium titanate is 3-4:4-6:1-2.

[0035] The strontium titanate nanomaterial described in the present invention is a powder coating used for photovoltaic module packaging materials and has excellent weather resistance; the nanomaterial described in the present invention is based on material size, namely nanoscale materials and microscale materials, and is not based on the amount of strontium titanate nano-additive used.

[0036] In the present invention, unless otherwise specified, the raw materials used are commercially available products well known to those skilled in the art or are prepared using methods well known to those skilled in the art.

[0037] The flexible composite material provided by the present invention includes fiber cloth. In the present invention, the fiber cloth is preferably glass fiber cloth, and the glass fiber cloth is preferably woven glass fiber cloth; the gram weight of the fiber cloth is preferably 100 to 400 g / m 2 , specifically 100g / m 2 , 200g / m 2 , 300g / m 2 or 400g / m 2 The thickness of the flexible composite material of the present invention is mainly affected by the basis weight of the fiber cloth. Specifically, in the present invention, the thickness of the flexible composite material is preferably 0.1 to 0.4 mm, more preferably 0.15 to 0.31 mm, and specifically can be 0.15 mm, 0.22 mm or 0.31 mm.

[0038] The flexible composite material provided by the present invention includes a strontium titanate nanomaterial composited in the fiber cloth, wherein the strontium titanate nanomaterial is specifically impregnated with and composited with the fibers in the fiber cloth. In the present invention, the content of the strontium titanate nanomaterial in the flexible composite material is preferably 50-80wt%, more preferably 51-78wt%, further preferably 52-75wt%, further preferably 53-70wt%, further preferably 54-65wt%, and further preferably 55-60wt%.

[0039] In the present invention, the raw materials for preparing the strontium titanate nanomaterial include a matrix material; by weight, the raw materials for preparing the matrix material include 50 to 90 parts, preferably 55 to 80 parts, more preferably 60 to 78 parts, further preferably 65 to 75 parts, and even more preferably 70 to 72 parts of a powdered resin. In the present invention, the powdered resin preferably includes one or more of an acrylic resin, a polyurethane resin, and a polyester resin, and is more preferably an acrylic resin.

[0040] The present invention preferably uses acrylic resin as the main material, which has the advantages of good weather resistance, high film-forming strength, excellent impact resistance and excellent flexibility. In the present invention, the acrylic resin is preferably an epoxy acrylic resin, more preferably the epoxy acrylic powder coating resin described in patent CN 115651473 A; specifically, the raw materials of the epoxy acrylic powder coating resin include 20 to 70 parts of hard monomer, 10 to 60 parts of soft monomer, 10 to 50 parts of cross-linking monomer and 0.5 to 8 parts of initiator; the cross-linking monomer includes epoxy-containing monomer and / or hydroxyl-containing monomer; the hard monomer includes at least one of methyl methacrylate, ethyl methacrylate, butyl methacrylate, isobornyl methacrylate, dicyclopentadiene acrylate, dicyclopentadiene ethoxyacrylate, styrene, methyl styrene or acrylonitrile; the soft monomer includes alkyl acrylate compounds; the epoxy-containing monomer includes at least one of glycidyl methacrylate, glycidyl acrylate, hydroxybutyl glycidyl ether or versatile glycidyl ether; the hydroxyl-containing The monomers include at least one of hydroxyethyl acrylate, hydroxyethyl methacrylate, hydroxypropyl acrylate, hydroxypropyl methacrylate, β-hydroxypropyl acrylate, β-hydroxypropyl methacrylate or N-hydroxymethyl acrylamide; the mass ratio of the epoxy-containing monomer to the hydroxyl-containing monomer in the cross-linking monomer is (2-15):1; the epoxy-type acrylic powder coating resin is prepared by the following method, which includes: dropwise adding a mixture of a hard monomer, a soft monomer, a cross-linking monomer, 40-50% of an initiator in the formula amount and an optional molecular weight regulator into a solvent; after a first reaction, dropwise adding the remaining initiator and continuing the reaction to obtain the epoxy-type acrylic powder coating resin; the temperature of the first reaction is 80-110° C., the time is 2-4 hours, and the time of the continued reaction is 2-4.5 hours.

[0041] Based on the mass fraction of the powdered resin, the raw materials for preparing the matrix material of the present invention include 10 to 50 parts of a curing agent, preferably 15 to 30 parts, more preferably 18 to 25 parts, and even more preferably 20 to 21 parts. In the present invention, the curing agent preferably includes one or more of dodecanoic acid (DDDA), triglycidyl isocyanurate (TGIC), and isocyanate, more preferably DDDA, TGIC, or isocyanate. The present invention preferably uses the above-mentioned types of curing agents, which are beneficial to improving film-forming efficiency while ensuring the basic physical properties of the film.

[0042] Based on the mass fraction of the powdered resin, the raw materials for preparing the matrix material of the present invention include 0 to 20 parts of an antioxidant, preferably 0.3 to 10 parts, more preferably 0.5 to 5 parts, and even more preferably 1 to 2 parts. In the present invention, the antioxidant preferably includes one or more of β-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate (Antioxidant 1076), benzofuranone derivatives, and thioesters, more preferably Antioxidant 1076. The present invention preferably uses the above-mentioned antioxidants to improve weather resistance.

[0043] Based on the mass fraction of the powdered resin, the raw materials for preparing the matrix material of the present invention include 0.05 to 0.2 parts of catalyst, preferably 0.06 to 0.15 parts, more preferably 0.07 to 0.1 parts, and even more preferably 0.075 to 0.085 parts. In the present invention, the catalyst preferably includes tetrabutylammonium bromide, dibutyltin dilaurate, or 2-propylimidazole, and more preferably tetrabutylammonium bromide. The present invention preferably uses the above-mentioned catalysts to improve film formation efficiency.

[0044] The raw materials used to prepare the matrix material of the present invention include 0 to 10 parts by weight of the powdered resin, preferably 0.3 to 5 parts, more preferably 0.5 to 2 parts, and even more preferably 0.8 to 1 part of a surface conditioner. In the present invention, the surface conditioner preferably includes benzoin. The preferred use of the above-mentioned surface conditioners in the present invention facilitates improved surface smoothness and light transmittance after film formation.

[0045] Based on the mass fraction of the powdered resin, the raw materials for preparing the matrix material of the present invention include 0 to 20 parts of a light stabilizer, preferably 0.5 to 15 parts, more preferably 0.8 to 10 parts, further preferably 1.2 to 7 parts, and even more preferably 1.66 to 3 parts. In the present invention, the light stabilizer preferably includes a triazine light stabilizer or a hindered amine light stabilizer, more preferably a triazine light stabilizer; the triazine light stabilizer is preferably 2-[2-hydroxy-4-[3-(2-ethylhexyloxy)-2-hydroxypropoxy]phenyl]-4,6-bis(2,4-dimethylphenyl)-1,3,5-triazine (light stabilizer UV-405); the hindered amine light stabilizer is preferably one or more of high molecular weight triazine-piperidine condensate (light stabilizer 119), Tinuvin 622, and Tinuvin 770. The present invention preferably uses the above-mentioned light stabilizers to improve weather resistance.

[0046] Based on the mass fraction of the powdered resin, the raw materials for preparing the matrix material in the present invention include 0.05 to 5 parts of strontium titanate nano-additive, preferably 0.1 to 4.8 parts, more preferably 0.5 to 4.5 parts, further preferably 1 to 4 parts, further preferably 1.5 to 3.5 parts, and even more preferably 2 to 3.45 parts. In the present invention, the strontium titanate nano-additive is a mixture of octahedral strontium titanate, hexahedral strontium titanate, and irregular strontium titanate, and the mass ratio of the octahedral strontium titanate, hexahedral strontium titanate, and irregular strontium titanate is 3 to 4:4 to 6:1 to 2, preferably 3 to 3.5:5 to 6:1 to 1.5, and more preferably 3:6:1. In the present invention, the particle size of the strontium titanate nano-additive is preferably 50 to 300 nm, more preferably 50 to 200 nm; in the present invention, the particle size of the octahedral strontium titanate is preferably 100 to 200 nm, the particle size (side length) of the hexahedral strontium titanate is preferably 100 to 200 nm, and the particle size of the irregular strontium titanate is preferably 50 to 100 nm. In the present invention, the strontium titanate nano-additive is obtained by compounding strontium titanate of a specific morphology, which can make the strontium titanate nano-material have excellent weather resistance; and the compounding of strontium titanate of different morphologies can provide different crystal planes, which is conducive to the efficient separation of photoinduced charges and holes, thereby improving the photoelectric conversion efficiency.

[0047] In the present invention, the raw materials for preparing the strontium titanate nanomaterial include a dispersant, which preferably includes one or more of alumina, fumed silica, and glass beads, with alumina being more preferred. In the present invention, the mass of the dispersant is 0.05-0.2% of the mass of the matrix material, preferably 0.1-0.15%. The preferred use of the above-mentioned dispersants helps prevent agglomeration and improves product processing performance.

[0048] In the present invention, the particle size of the matrix material is preferably 30 to 150 μm; the particle size of the dispersant is preferably 2 to 8 μm, more preferably 2 to 4 μm.

[0049] The present invention provides a method for preparing the strontium titanate nanomaterial described in the above technical solution, comprising the following steps:

[0050] The raw materials for preparing the matrix material are mixed, and the mixture is subjected to melt extrusion, cooling, crushing and screening in sequence to obtain the matrix material; the matrix material is mixed with a dispersant to obtain the strontium titanate nanomaterial;

[0051] Alternatively, the raw materials for preparing the matrix material are mixed with a dispersant, and the mixture is melt-extruded, cooled, crushed and sieved in sequence to obtain the strontium titanate nanomaterial.

[0052] In the present invention, different methods can be used to prepare the strontium titanate nanomaterials according to the timing of adding the dispersant, which will be described in detail below.

[0053] Method 1: The raw materials for preparing the matrix material are mixed and sequentially subjected to melt extrusion, cooling, pulverization, and screening to obtain the matrix material. The matrix material is then mixed with a dispersant to obtain the strontium titanate nanomaterial. In the present invention, the raw materials for preparing the matrix material are preferably mixed mechanically. The conditions for mechanical mixing are not particularly limited, as long as the raw materials are uniformly mixed. In the present invention, the temperature for melt extrusion is preferably 90-130°C, more preferably 110-120°C. The cooling method is not particularly limited, and any cooling method known to those skilled in the art can be employed. In the present invention, the pulverization preferably includes a first pulverization and a second pulverization. The first pulverization preferably pulverizes the material to a particle size of 0.2-1 cm, and the second pulverization preferably pulverizes the material to a particle size of 30-150 μm. The screening method is not particularly limited, as long as a matrix material of the desired particle size is obtained. In the present invention, the raw materials for preparing the matrix material are preferably mixed mechanically. The conditions for mechanical mixing are not particularly limited, as long as the matrix material and dispersant are uniformly mixed.

[0054] The second method: The present invention mixes the raw materials for preparing the matrix material with a dispersant, and sequentially melt-extrudes, cools, crushes and screens to obtain the strontium titanate nanomaterial. In the present invention, the raw materials for preparing the matrix material and the dispersant are preferably mixed mechanically. The present invention does not specifically limit the conditions for the mechanical mixing, as long as the raw materials are uniformly mixed. In the present invention, the specific operations of melt extrusion, cooling, crushing and screening involved in the second method are preferably consistent with the specific operations of melt extrusion, cooling, crushing and screening involved in the first method, and will not be repeated here.

[0055] The present invention provides a method for preparing the flexible composite material described in the above technical solution, comprising the following steps:

[0056] The fiber cloth is impregnated with molten strontium titanate nanomaterials and then solidified to obtain a flexible composite material.

[0057] The present invention can impregnate the fiber cloth with the molten strontium titanate nanomaterial by different methods, which are described in detail below.

[0058] The first method is to lay the strontium titanate nanomaterial on the surface of the fiber cloth, and heat it with a laminating device or a rolling device to melt the strontium titanate nanomaterial and impregnate the fiber cloth. The present invention preferably uses a powdering device to evenly sprinkle the strontium titanate nanomaterial on the surface of the fiber cloth, and then put the fiber cloth with the strontium titanate nanomaterial on the surface into the laminating device, close the mold and heat it to melt the strontium titanate nanomaterial and impregnate the fiber cloth; or use a rolling device to roll and heat the fiber cloth with the strontium titanate nanomaterial on the surface to melt the strontium titanate nanomaterial and impregnate the fiber cloth. The present invention uses a rolling device to facilitate continuous production. In the present invention, the powdering speed of the powdering device is preferably 1 to 10 m / min, more preferably 2 to 6 m / min, and even more preferably 3 to 4 m / min. In the present invention, the heating temperature is based on ensuring the melting of the strontium titanate nanomaterial. Specifically, the heating temperature is preferably 130-170°C, more preferably 130-160°C, and further preferably 130-150°C.

[0059] The second method involves extruding the strontium titanate nanomaterial to obtain a resin film, laminating the resin film onto the surface of the fiber cloth, and heating the film via a laminating device or a rolling device to melt the resin film and impregnate the fiber cloth. The present invention preferably utilizes an extrusion device to extrude the strontium titanate nanomaterial to obtain a resin film, laminating the resin film onto the surface of the fiber cloth, and then rolling and heating the fiber cloth laminating the resin film with a rolling device to melt the resin film and impregnate the fiber cloth with the molten strontium titanate nanomaterial. The use of a rolling device facilitates continuous production. In the present invention, the extrusion speed of the extruder is preferably 1 to 10 m / min, more preferably 1 to 6 m / min. In the present invention, the heating temperature is based on ensuring that the resin film melts. Specifically, the heating temperature is preferably 130 to 170°C, more preferably 130 to 160°C, and even more preferably 130 to 150°C.

[0060] After impregnating the fiber cloth with molten strontium titanate nanomaterial, the present invention solidifies the obtained material to obtain a flexible composite material. In the present invention, the curing temperature is preferably 130-200°C, more preferably 140-170°C, and further preferably 150-160°C; the pressure is preferably 1-20MPa, more preferably 5-15MPa, and further preferably 8-10MPa; the time is preferably 10-90min, more preferably 20-60min, and further preferably 30-40min. In the present invention, when a laminating device is used to prepare the flexible composite material, the curing is preferably followed by cooling and demoulding to obtain a flexible composite material; when a rolling device is used to prepare the flexible composite material, the curing is preferably followed by winding or cutting into the desired size to obtain a flexible composite material.

[0061] The present invention provides the use of the flexible composite material described in the above technical solution, or the flexible composite material prepared by the preparation method described in the above technical solution, as a photovoltaic module encapsulation material. In the present invention, the photovoltaic module is preferably a lightweight photovoltaic module. In the present invention, the encapsulation material can be used for the front panel or the back panel of the photovoltaic module.

[0062] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions of the present invention. Obviously, the embodiments described are only some of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0063] The strontium titanate nano-additive used in the examples of the present invention is the product prepared in Preparation Examples 1 to 3.

[0064] Preparation Example 1

[0065] The steps for preparing hexahedral strontium titanate nanoparticles are as follows:

[0066] Palmitic acid, ethylene glycol, 1,2-butanediol, and water are mixed to obtain a composite morphology regulator, wherein the concentration of palmitic acid, the concentration of ethylene glycol, and the concentration of 1,2-butanediol are 0.2 wt %, and the concentration of 1,2-butanediol are 2 wt %; a titanium tetrachloride aqueous solution having a concentration of 0.003 g / mL is added dropwise to the composite morphology regulator, and the volume ratio of the composite morphology regulator to the titanium tetrachloride aqueous solution is 1:2, and the mixture is stirred for 30 minutes. During the stirring process, the mixture is cooled with ice water to obtain a mixed solution I;

[0067] The mixed solution I, a lithium hydroxide aqueous solution with a concentration of 0.033 g / mL, and a strontium hydroxide aqueous solution with a concentration of 0.01 g / mL were mixed in a volume ratio of 3:3:1, and stirred for 15 minutes to obtain a mixed solution II with a pH value of 13.8;

[0068] The mixed solution II was heated to 180°C at a heating rate of 4°C / min for a hydrothermal reaction for 48 hours, and then cooled at a cooling rate of 2°C / min. The material after the hydrothermal reaction was centrifuged, and the precipitate was washed alternately with water and ethanol 5 times, and finally dried at 90°C for 4 hours to obtain hexahedral strontium titanate nanoparticles.

[0069] Preparation Example 2

[0070] The steps for preparing octahedral strontium titanate nanoparticles are as follows:

[0071] Palmitic acid, ethylene glycol, 1,2-butanediol, and water are mixed to obtain a composite morphology regulator, wherein the concentration of palmitic acid in the composite morphology regulator is 0.2 wt %, the concentration of ethylene glycol is 1 wt %, and the concentration of 1,2-butanediol is 0.2 wt %; a titanium tetrachloride aqueous solution having a concentration of 0.003 g / mL is added dropwise to the composite morphology regulator, and the volume ratio of the composite morphology regulator to the titanium tetrachloride aqueous solution is 1:2, and the mixture is stirred for 30 minutes. During the stirring process, ice water is used for cooling to obtain a mixed solution I;

[0072] The mixed solution I, a sodium hydroxide aqueous solution with a concentration of 0.033 g / mL, and a strontium chloride hexahydrate aqueous solution with a concentration of 0.01 g / mL were mixed in a volume ratio of 3:3:1, and stirred for 30 minutes to obtain a mixed solution II with a pH value of 14.2;

[0073] The mixed solution II was heated to 190°C at a heating rate of 4°C / min for a hydrothermal reaction for 24 hours, and then cooled at a cooling rate of 2°C / min. The material after the hydrothermal reaction was centrifuged, and the precipitate was washed alternately with water and ethanol three times, and finally dried at 80°C for 6 hours to obtain octahedral strontium titanate nanoparticles.

[0074] Preparation Example 3

[0075] The steps for preparing irregular strontium titanate are as follows:

[0076] Palmitic acid, ethylene glycol, 1,2-butanediol, and water were mixed to obtain a composite morphology regulator, wherein the concentration of palmitic acid in the composite morphology regulator was 0.2 wt %, the concentration of ethylene glycol was 1.2 wt %, and the concentration of 1,2-butanediol was 1.6 wt %; a titanium tetrachloride aqueous solution having a concentration of 0.003 g / mL was added dropwise to the composite morphology regulator, with the volume ratio of the composite morphology regulator to the titanium tetrachloride aqueous solution being 1:2, and the mixture was stirred for 30 minutes, cooling with ice water during the stirring process to obtain a mixed solution I;

[0077] The mixed solution I, a sodium hydroxide aqueous solution with a concentration of 0.033 g / mL, and a strontium chloride hexahydrate aqueous solution with a concentration of 0.01 g / mL were mixed in a volume ratio of 3:3:1, and stirred for 30 minutes to obtain a mixed solution II with a pH value of 14.2;

[0078] The mixed solution II was heated to 180°C at a heating rate of 4°C / min for a hydrothermal reaction for 72 hours, and then cooled at a cooling rate of 2°C / min. The material after the hydrothermal reaction was centrifuged, and the precipitate was washed alternately with water and ethanol 5 times, and finally dried at 80°C for 6 hours to obtain irregular strontium titanate nanoparticles.

[0079] Example 1

[0080] In this embodiment, the raw materials for preparing strontium titanate nanomaterials include a base material and a dispersant;

[0081] 72 parts by mass of an acrylic resin (specifically, the epoxy acrylic powder coating resin prepared in Example 7 of patent CN 115651473 A), 21 parts of a curing agent (specifically, DDDA), 1 part of an antioxidant (specifically, antioxidant 1076), 0.085 parts of a catalyst (specifically, tetrabutylammonium bromide), 0.8 parts of a surface conditioner (specifically, benzoin), 1.66 parts of a light stabilizer (specifically, light stabilizer UV-405), and 3.45 parts of a strontium titanate nano-additive (specifically, a mixture of octahedral strontium titanate, hexahedral strontium titanate, and irregular strontium titanate in a mass ratio of 3:6:1) were mixed, melt-extruded at 120° C., and the resulting extrudate was cooled and crushed to a particle size of 0.2 to 1 cm. The extrudate was then further crushed and graded and sieved to obtain a matrix material with a particle size of 30 to 150 μm.

[0082] The dispersant is aluminum oxide, and the particle size of the dispersant is 2 to 4 μm; the mass of the dispersant is 0.1% of the mass of the base material;

[0083] The matrix material is mixed with a dispersant to obtain strontium titanate nanomaterials.

[0084] Use powder spreading equipment to evenly spread strontium titanate nanomaterials on glass fiber cloth (specifically woven glass fiber cloth with a gram weight of 100g / m 2 ) at a powder sprinkling speed of 4 m / min, loading a glass fiber cloth sprinkled with strontium titanate nanomaterials onto a laminating device, closing the mold and heating to a temperature of 130° C. to melt the strontium titanate nanomaterials and impregnate the glass fiber cloth, and then curing the composite material at a temperature of 160° C. and a pressure of 10 MPa for 30 min. After curing, cooling the composite material and demoulding the composite material to obtain a flexible composite material. The content of strontium titanate nanomaterials in the flexible composite material is 55 wt %, and the thickness of the flexible composite material is 0.15 mm.

[0085] Example 2

[0086] A flexible composite material was prepared according to the method of Example 1, except that the weight of the glass fiber cloth used was 200 g / m 2 , the thickness of the flexible composite material is 0.22 mm.

[0087] Example 3

[0088] A flexible composite material was prepared according to the method of Example 1, except that the weight of the glass fiber cloth used was 300 g / m 2 , the thickness of the flexible composite material is 0.31 mm.

[0089] Example 4

[0090] A flexible composite material was prepared according to the method of Example 1, except that the content of strontium titanate nanomaterial in the flexible composite material was 60 wt %.

[0091] Comparative Example 1

[0092] The flexible composite material was prepared according to the method of Example 1, except that the strontium titanate nano-additive in the strontium titanate nano-material was omitted.

[0093] Test Example 1

[0094] The strength of the flexible composite materials prepared in Examples 1 to 4 and Comparative Example 1 was tested according to the method of GB / T 13542.2-2021 (the product strength requirement is ≥100 MPa), and the water permeability of the flexible composite materials prepared in Examples 1 to 4 and Comparative Example 1 was tested according to the method of GB / T 21529-2008 (the product water permeability requirement is ≤1.5 g / (m 2 ·24h)), the results are shown in Table 1.

[0095] Table 1 Performance test results of flexible composite materials prepared in Examples 1 to 4 and Comparative Example 1

[0096] As shown in Examples 1 to 3 in Table 1, the greater the gram weight of the glass fiber cloth, the thicker the prepared flexible composite material, the greater its tensile strength, and the higher its water permeability. As shown in Examples 1 and 4, as the content of strontium titanate nanomaterial in the flexible composite material increases, the strength of the flexible composite material decreases and the water permeability decreases slightly. As shown in Example 1 and Comparative Example 1, omitting the strontium titanate nano-additive from the strontium titanate nanomaterial does not significantly change the strength and water permeability of the flexible composite material. This indicates that adding strontium titanate nanomaterials during the preparation of the flexible composite material can still enable the flexible composite material to maintain good mechanical properties and water barrier properties.

[0097] Comparative Example 2

[0098] A flexible composite material was prepared according to the method of Example 1, except that the strontium titanate nanomaterial was replaced with a commercially available flexible photovoltaic material.

[0099] Test Example 2

[0100] The elongation at break and light transmittance of the flexible composite materials prepared in Example 1 and Comparative Example 2 were tested and compared with those of traditional photovoltaic glass. The elongation at break was tested according to GB / T 13542.2-2021, and the light transmittance was tested according to GB / T 2410-2008. The results are shown in Table 2. As shown in Table 2, while the light transmittance of the flexible composite material prepared using strontium titanate nanomaterials is lower than that of traditional photovoltaic glass, its elongation at break and light transmittance are superior to those of flexible composite materials prepared using commercially available flexible photovoltaic materials, and its elongation at break is also superior to that of traditional photovoltaic glass.

[0101] Table 2 Performance test results of flexible composite materials and photovoltaic glass prepared in Example 1 and Comparative Example 2

[0102] Test Example 3

[0103] The weather resistance of the flexible composite materials prepared in Example 1 and Comparative Examples 1 and 2 was tested according to the method of GB / T 29848-2018, and the results are shown in Table 3. As can be seen from Table 3, the flexible composite material prepared in Example 1 of the present invention, in which the strontium titanate nanomaterial is compounded in the fiber cloth and the strontium titanate nano-additive is added to the matrix material of the strontium titanate nanomaterial, can provide the flexible composite material with excellent weather resistance, such as UV resistance and heat and humidity resistance, which are superior to those of the flexible composite materials prepared in Comparative Examples 1 and 2.

[0104] Table 3 Performance test results of the flexible composite materials prepared in Example 1 and Comparative Examples 1-2

[0105] The above test examples show that the flexible composite material provided by the present invention has excellent weather resistance, and also has the characteristics of light weight, high strength, high light transmittance and good water barrier performance. In addition, the flexible composite material provided by the present invention has the characteristics of high anti-fouling and easy cleaning. Usually, the main dirt can be removed by washing with rainwater, and the expected outdoor service life is more than 25 years.

[0106] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as within the scope of protection of the present invention.

Claims

1. A flexible composite material, comprising a fiber cloth and a strontium titanate nanomaterial composited in the fiber cloth; The raw materials for preparing the strontium titanate nanomaterial include a base material and a dispersant, wherein the mass of the dispersant is 0.05-0.2% of the mass of the base material; the base material includes the following raw materials by mass: 50-90 parts of powdered resin; 10-50 parts of curing agent; 0-20 parts of antioxidant; 0.05-0.2 parts of catalyst; 0-10 parts of surface adjuster; 0-20 parts of light stabilizer; 0.05-5 parts of strontium titanate nano-additive, wherein the strontium titanate nano-additive is a mixture of octahedral strontium titanate, hexahedral strontium titanate and irregular strontium titanate, and the mass ratio of the octahedral strontium titanate, the hexahedral strontium titanate and the irregular strontium titanate is 3-4:4-6:1-2.

2. The flexible composite material according to claim 1, characterized in that: The fiber cloth is glass fiber cloth.

3. The flexible composite material according to claim 2, characterized in that: The fiber cloth has a gram weight of 100 to 400 g / m 2 .

4. The flexible composite material according to claim 1, characterized in that: The particle size of the strontium titanate nano-additive is 50-300nm.

5. The flexible composite material according to claim 4, characterized in that: The particle size of the octahedral strontium titanate is 100-200 nm; the particle size of the hexahedral strontium titanate is 100-200 nm; and the particle size of the irregular strontium titanate is 50-100 nm.

6. The flexible composite material according to claim 1, characterized in that: The powder resin includes one or more of acrylic resin, polyurethane resin and polyester resin.

7. The flexible composite material according to claim 6, characterized in that: The acrylic resin is an epoxy acrylic resin.

8. The flexible composite material according to claim 1, characterized in that: The curing agent includes one or more of dodecanedioic acid, triglycidyl isocyanurate and isocyanate.

9. The flexible composite material according to claim 1, characterized in that: The antioxidant auxiliary agent includes one or more of β-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate, benzofuranone derivatives and thioester antioxidants.

10. The flexible composite material according to claim 1, characterized in that: The catalyst includes tetrabutylammonium bromide, dibutyltin dilaurate or 2-propylimidazole.

11. The flexible composite material according to claim 1, characterized in that: The surface conditioning agent includes benzoin.

12. The flexible composite material according to claim 1, characterized in that: The light stabilizer includes a triazine light stabilizer or a hindered amine light stabilizer.

13. The flexible composite material according to claim 1, characterized in that: The particle size of the matrix material is 30 to 150 μm.

14. The flexible composite material according to claim 1, characterized in that: The particle size of the dispersant is 2 to 8 μm.

15. The flexible composite material according to claim 1, characterized in that: The dispersant includes one or more of alumina, fumed silica and glass microspheres.

16. The flexible composite material according to any one of claims 1 to 15, characterized in that: The content of strontium titanate nanomaterials in the flexible composite material is 50-80wt%.

17. A method for preparing the flexible composite material according to any one of claims 1 to 16, comprising the following steps: The fiber cloth is impregnated with molten strontium titanate nanomaterials and then solidified to obtain a flexible composite material.

18. The preparation method according to claim 17, characterized in that: The method of using molten strontium titanate nano-material to impregnate the fiber cloth comprises the following steps: The strontium titanate nano-micro material is laid on the surface of the fiber cloth, and is heated by a laminating device or a rolling device to melt the strontium titanate nano-micro material and infiltrate the fiber cloth.

19. The preparation method according to claim 17, characterized in that: The method of using molten strontium titanate nano-material to impregnate the fiber cloth comprises the following steps: The strontium titanate nanomaterial is extruded to obtain a resin film, the resin film is laminated and compounded on the surface of the fiber cloth, and heated by a laminating device or a rolling device to melt the resin film and infiltrate the fiber cloth.

20. The preparation method according to any one of claims 17 to 19, characterized in that: The curing temperature is 130-200° C., the pressure is 1-20 MPa, and the curing time is 10-90 minutes.

21. Use of the flexible composite material according to any one of claims 1 to 16 or the flexible composite material prepared by the preparation method according to any one of claims 17 to 20 as a photovoltaic module packaging material.

22. The use according to claim 21, characterized in that The packaging material is the packaging material of the front panel or the packaging material of the back panel of the photovoltaic module.

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