An edge sealing adhesive tape for photovoltaic modules and a preparation method and application thereof

Abstract

The application provides an edge sealing adhesive tape for photovoltaic modules and a preparation method and application thereof. The edge sealing adhesive tape for photovoltaic modules comprises, from top to bottom, an insulating glass cloth, a modified silicone rubber layer, a modified pressure-sensitive adhesive layer and a release film layer. The edge sealing adhesive tape is suitable for the insulation sealing protection of photovoltaic modules in extreme environments, and can be widely adapted to crystalline silicon photovoltaic modules, thin-film photovoltaic modules, BIPV modules and high-temperature environment special photovoltaic modules.

Description

Technical Field

[0001] This invention belongs to the technical field of photovoltaic module protective materials, and relates to a sealing tape for photovoltaic modules, its preparation method and application. Background Technology

[0002] During long-term outdoor operation, photovoltaic modules must withstand various harsh environmental factors such as extreme temperature differences, strong ultraviolet radiation, salt spray corrosion, and drastic humidity changes. As a key protective material for photovoltaic modules, the edge sealing tape's core indicators, such as insulation performance, weather resistance, and mechanical strength, directly determine the safe operation and service life of the photovoltaic modules.

[0003] Most photovoltaic edge sealing tapes currently on the market use single polyolefins or ordinary silicone rubber as the base material. In practical applications, this presents several technical challenges, making it difficult to meet the protection requirements of photovoltaic modules in extreme environments: Insufficient insulation performance: The dielectric strength of traditional polyolefin base materials is typically only 15-25kV / mm, and the volume resistivity is ≤10. 12 In high-voltage photovoltaic modules, the Ω·cm value poses a significant risk of current leakage, seriously threatening the safe operation of the photovoltaic system. Furthermore, the narrow temperature range of conventional sealing tapes, typically operating between -40℃ and 120℃, makes them unsuitable for extreme temperature environments such as high-temperature deserts (ambient temperature ≥60℃) and frigid regions (ambient temperature ≤-40℃). In these areas, the tape's performance is prone to significant degradation. A conflict exists between mechanical strength and flexibility: while pure silicone rubber substrates possess good weather resistance, their low tensile strength (≤5MPa) and poor tear resistance make them susceptible to damage during photovoltaic module installation and transportation, leading to protective failure. Finally, limited aging resistance is another concern: ordinary acrylic adhesives are prone to yellowing under prolonged UV exposure, resulting in a significant decrease in adhesion and ultimately causing the tape to peel off from the photovoltaic module substrate, losing its sealing and insulation effect and shortening the photovoltaic module's lifespan.

[0004] Therefore, developing a photovoltaic sealing tape that combines high insulation performance, wide temperature range adaptability, excellent mechanical strength, and long-lasting aging resistance is key to solving the protection problem of photovoltaic modules in extreme environments and is of great significance to promoting the development of the photovoltaic industry in complex environments. Summary of the Invention

[0005] To address the shortcomings of existing technologies, the present invention aims to provide an edge-sealing tape for photovoltaic modules, its preparation method, and its application. The edge-sealing tape of the present invention is suitable for the insulation and sealing protection of photovoltaic modules in extreme environments and can be widely adapted to crystalline silicon photovoltaic modules, thin-film photovoltaic modules, BIPV modules, and photovoltaic modules designed for high-temperature environments.

[0006] To achieve this objective, the present invention adopts the following technical solution: On one hand, the present invention provides a sealing tape for photovoltaic modules, which comprises, from top to bottom, an insulating fiberglass cloth, a modified silicone rubber layer, a modified pressure-sensitive adhesive layer and a release film layer.

[0007] Preferably, the insulating fiberglass cloth is alkali-free fiberglass cloth.

[0008] In this invention, the insulating fiberglass cloth is an inorganic non-metallic material woven from glass fiber, possessing excellent mechanical properties, chemical resistance, and insulation. It is widely used in composite material reinforcement (such as fiberglass), electronic insulation, building waterproofing, and adhesive / tape substrates. It exhibits high mechanical strength: tensile strength can reach 2000-3500 MPa (e.g., 2000 MPa, 2100 MPa, 2200 MPa, 2300 MPa, 2400 MPa, 2500 MPa, 2600 MPa, 2700 MPa, 2800 MPa, 2900 MPa, 3000 MPa, 3100 MPa, 3200 MPa, 3300 MPa, or 3500 MPa, etc.), and its specific strength (strength / density) is far higher than that of steel, effectively improving the load-bearing capacity of composite materials. It also possesses chemical stability: except for hydrofluoric acid and concentrated alkalis, it has good resistance to acids, alkalis, salts, and organic solvents, and can be used for extended periods in corrosive environments. Excellent insulation properties: Glass fiber itself is an inorganic insulating material, and fiberglass cloth can be used as an insulating pad for motors and electrical appliances or as a substrate for circuit boards. High temperature resistance: Alkali-free fiberglass cloth can withstand long-term operating temperatures up to 550℃, while medium-alkali fiberglass cloth can withstand around 300℃, far superior to organic fiber fabrics. Low shrinkage: Heat shrinkage rate <0.1% (below 200℃), strong dimensional stability, suitable for high-precision composite material molding. Using alkali-free fiberglass cloth (E-glass) as the reinforcing substrate, it inherently possesses excellent insulation properties (volume resistivity ≥10). 16 It possesses high strength (tensile strength ≥300MPa) and good dimensional stability, with a thickness of 0.05-0.5mm. To improve the interfacial bonding force with the silicone rubber matrix, the alkali-free fiberglass cloth is surface-modified with a silane coupling agent (KH-550 or KH-560). After treatment, the interfacial bonding force between the fiberglass cloth and the silicone rubber matrix is ​​increased by more than 40%, effectively solving the problem of easy delamination in traditional composite substrates.

[0009] Preferably, the modified silicone rubber comprises the following components: a silicone rubber matrix, inorganic reinforcing fillers, a crosslinking agent, and an antioxidant.

[0010] Preferably, the silicone rubber matrix includes at least one of methyl vinyl silicone rubber (MVQ) or phenyl silicone rubber (PVMQ).

[0011] Preferably, the inorganic reinforcing filler includes at least one of nano-silica (particle size 10-50nm, such as 10nm, 15nm, 20nm, 25nm, 30nm, 35nm, 40nm, 45nm or 50nm) or fumed silica.

[0012] Preferably, the crosslinking agent is a peroxide-based crosslinking agent, an addition vulcanization system, or a hydrogen-containing silicone oil; Preferably, the peroxide crosslinking agent includes any one or a combination of at least two of 2,5-dimethyl-2,5-bis(tert-butylperoxy)hexane (bis2,5)peroxide dicumylbenzene (DCP) or tert-butylisopropylbenzene peroxide; Preferably, the hydrogen-containing silicone oil includes methyl hydrogen-containing silicone oil, phenyl hydrogen-containing silicone oil, or multi-arm hydrogen-containing silicone oil.

[0013] The crosslinking agent described in this invention is odorless, dimensionally stable, and suitable for precision molding and liquid silicone.

[0014] Preferably, the antioxidant is one or a combination of at least two of the following: aromatic amine antioxidants, hindered phenolic antioxidants, and auxiliary antioxidants.

[0015] Preferably, the modified silicone rubber comprises the following components by weight percentage: 70-90 wt% silicone rubber matrix (e.g., 70 wt%, 71 wt%, 72 wt%, 73 wt%, 74 wt%, 75 wt%, 76 wt%, 77 wt%, or 85 wt%, 88 wt%, etc.), 10-20 wt% inorganic reinforcing filler (e.g., 10 wt%, 11 wt%, 12 wt%, 13 wt%, 14 wt%, 15 wt%, 16 wt%, 17 wt%, 18 wt%, or 20 wt%, etc.), 2-5 wt% crosslinking agent (e.g., 2 wt%, 2.3 wt%, 2.6 wt%, 2.9 wt%, 3.2 wt%, 3.5 wt%, 3.8 wt%, 4.1 wt%, 4.4 wt%, or 5 wt%, etc.), and 0.5-1 wt% antioxidant (e.g., 0.5 wt%, 0.6 wt%, 0.7 wt%, 0.8 wt%, 0.9 wt%, or 1 wt%, etc.).

[0016] In this invention, a three-dimensional network structure is formed through physical blending and chemical cross-linking. This retains the low dielectric properties (dielectric constant ≤3.0, dielectric loss ≤0.003) and wide temperature range adaptability (-50℃-200℃, such as -50℃, -25℃, 0℃, 25℃, 50℃, 75℃, 100℃, 125℃, 150℃ or 200℃, etc.) of silicone rubber, while increasing the tensile strength from 3-5MPa (such as 3MPa, 3.5MPa, 4MPa, 4.5MPa or 5MPa, etc.) of pure silicone rubber to ≥9.0MPa, the elongation at break ≥500%, and the tear strength ≥25N / mm, achieving a synergistic function of "rigid support-elastic buffer".

[0017] Preferably, the thickness of the modified silicone rubber layer is 0.05-0.3 mm, such as 0.05 mm, 0.1 mm, 0.15 mm, 0.2 mm or 0.3 mm.

[0018] Preferably, the thickness of the insulating fiberglass cloth is 0.2-0.5 mm, such as 0.2 mm, 0.24 mm, 0.28 mm, 0.32 mm, 0.36 mm, 0.4 mm, 0.44 mm, 0.48 mm or 0.5 mm.

[0019] Preferably, the raw materials for preparing the modified pressure-sensitive adhesive layer include the following components in parts by weight: 100 parts of solvent-based pressure-sensitive adhesive Hardener 0.2-10 parts Antioxidant 0.5-10 parts 0.5 to 5 parts of ultraviolet absorber 5-30 parts of tackifying resin Coupling agent 0.1-5 parts Organic solvents: 0-60 parts.

[0020] In the raw materials for preparing the modified pressure-sensitive adhesive layer of the present invention, relative to 100 parts of solvent-based pressure-sensitive adhesive, the amount of curing agent is 0.2 to 10 parts (e.g., 0.2 parts, 1 part, 2 parts, 3 parts, 4 parts, 5 parts, 6 parts, 7 parts, 8 parts, 9 parts, or 10 parts, etc.), the amount of antioxidant is 0.5 to 10 parts (e.g., 0.5 parts, 1 part, 2 parts, 3 parts, 4 parts, 5 parts, 6 parts, 7 parts, 8 parts, 9 parts, or 10 parts, etc.), and the amount of ultraviolet absorber is 0.5 to 5 parts (e.g., 0.5 parts, 1 part, 1.5 parts, 2 ... 0.5 parts, 3 parts, 3.5 parts, 4 parts, 4.5 parts or 5 parts, etc.), 5 to 30 parts of tackifying resin (e.g., 5 parts, 8 parts, 11 parts, 14 parts, 17 parts, 20 parts, 23 parts, 26 parts or 30 parts, etc.), 0.1 to 5 parts of coupling agent (e.g., 0.1 parts, 0.8 parts, 1.5 parts, 2.2 parts, 2.9 parts, 3.6 parts, 4.3 parts or 5 parts, etc.), 0 to 60 parts of organic solvent (e.g., 0 parts, 5 parts, 10 parts, 15 parts, 20 parts, 25 parts, 30 parts, 35 parts, 40 parts or 60 parts, etc.).

[0021] Preferably, the solvent-based pressure-sensitive adhesive is selected from one or a mixture of at least two of polyurethane pressure-sensitive adhesives, silicone pressure-sensitive adhesives, acrylic pressure-sensitive adhesives, natural rubber-based pressure-sensitive adhesives, and synthetic rubber-based pressure-sensitive adhesives.

[0022] Preferably, the crosslinking agent is any one or a combination of at least two of epoxy crosslinking agents, isocyanate crosslinking agents, organic peroxides, and metal oxides.

[0023] Preferably, the antioxidant is one or a combination of at least two of the following: aromatic amine antioxidants, hindered phenolic antioxidants, and auxiliary antioxidants.

[0024] Preferably, the ultraviolet absorber is selected from one or a mixture of at least two of the following: salicylates, benzophenones, benzimidazoles, substituted acrylonitriles, triazines, and hindered amine compounds.

[0025] Preferably, the tackifying resin is one or a combination of at least two of the following: rosin resin, modified rosin resin, terpene resin, and synthetic petroleum resin.

[0026] Preferably, the coupling agent is any one or a combination of at least two of vinyltrimethoxysilane, vinyltriethoxysilane, vinyltri(β-methoxyethoxy)silane, N-(2-aminoethyl-3-aminopropyl)trimethoxysilane, 3-(2,3-epoxypropoxy)propylmethyldiethoxysilane, 3-(methacryloylchloro)propyltrimethoxysilane, or γ-methacryloyloxypropyltrimethoxysilane.

[0027] Preferably, the organic solvent is selected from any one or a combination of at least two of ethyl acetate (EA), butyl acetate (BAC), n-butyl acetate, isopropyl acetate (IPA-E), sec-butyl acetate (SBA), acetone butanone (MEK), methyl ethyl ketone, methyl isobutyl ketone (MIBK), cyclohexanone, toluene, and xylene.

[0028] Preferably, the thickness of the pressure-sensitive adhesive layer is 0.05 to 0.15 mm, such as 0.05 mm, 0.06 mm, 0.07 mm, 0.08 mm, 0.09 mm, 0.1 mm, 0.11 mm, 0.12 mm, 0.13 mm, or 0.15 mm.

[0029] In this invention, the release film layer used is a release film coated with silicone or fluorine release agent, and the substrate is a polyester film or PP release film. This ensures that the tape does not stick together during storage and transportation, while also meeting the requirements for rapid peeling during automated assembly, thereby improving the production efficiency of photovoltaic modules.

[0030] Preferably, the thickness of the substrate is 0.025-0.15 mm, such as 0.025 mm, 0.045 mm, 0.065 mm, 0.085 mm, 0.105 mm, 0.125 mm, 0.145 mm or 0.15 mm.

[0031] On the other hand, the present invention provides a method for preparing the edge-sealing tape for photovoltaic modules as described above, the method comprising the following steps: (1) The modified silicone rubber liquid is uniformly coated on the surface of the insulating fiberglass cloth and cured to obtain the modified silicone rubber layer of the insulating fiberglass cloth; (2) The modified pressure-sensitive adhesive is coated on the surface of the modified silicone rubber layer of insulating fiberglass cloth and dried to obtain the modified pressure-sensitive adhesive layer; (3) The material obtained in step (2) is combined with the release film to obtain the sealing tape for the photovoltaic module.

[0032] Preferably, the modified silicone rubber solution in step (1) is obtained by mixing the raw material components of the modified silicone rubber and then performing vacuum degassing treatment.

[0033] In this invention, the mixing is performed by stirring at a speed of 1000-1500 r / min (e.g., 1000 r / min, 1050 r / min, 1100 r / min, 1150 r / min, 1200 r / min, 1250 r / min, 1300 r / min, 1350 r / min, 1400 r / min or 1500 r / min, etc.) for 30-60 min (e.g., 30 min, 34 min, 38 min, 42 min, 46 min, 50 min, 54 min or 60 min, etc.).

[0034] Preferably, the amount of coating in step (1) is 50-100 g / m 2 For example, 50g / m 2 55g / m 2 60g / m 2 65g / m 2 70g / m 2 75g / m 2 80g / m 2 85g / m 2 90g / m 2 Or 100g / m 2 wait.

[0035] Preferably, the curing temperature in step (1) is 120-160℃ (e.g., 120℃, 125℃, 130℃, 135℃, 140℃, 145℃, 150℃, 155℃ or 160℃, etc.), and the curing time is 10-30min (e.g., 10min, 15min, 20min, 25min or 30min, etc.).

[0036] Preferably, the insulating fiberglass cloth is pretreated before use, and the pretreatment includes the following steps: Fiberglass cloth is immersed in an aqueous solution of silane coupling agent and then dried to obtain surface-modified fiberglass cloth.

[0037] Preferably, the basis weight of the fiberglass cloth is 50-150 g / m². 2 (e.g., 50g / m 2 60g / m 2 70g / m 2 80g / m 2 90g / m 2 100g / m 2 110g / m 2 120g / m 2 130g / m 2 Or 150g / m 2(etc.), with a thickness of 0.1-0.3mm (e.g., 0.1mm, 0.12mm, 0.14mm, 0.16mm, 0.18mm, 0.2mm, 0.22mm, 0.24mm or 0.3mm, etc.).

[0038] Preferably, the silane coupling agent is any one or a combination of at least two of vinyltrimethoxysilane, vinyltriethoxysilane, vinyltri(β-methoxyethoxy)silane, N-(2-aminoethyl-3-aminopropyl)trimethoxysilane, 3-(2,3-epoxypropoxy)propylmethyldiethoxysilane, 3-(methacryloylchloro)propyltrimethoxysilane, or γ-methacryloyloxypropyltrimethoxysilane.

[0039] Preferably, the concentration of the aqueous solution of the silane coupling agent is 1-3 wt%, such as 1 wt%, 1.5 wt%, 2 wt%, 2.5 wt%, or 3 wt%.

[0040] Preferably, the soaking time is 10-20 minutes, such as 10 minutes, 11 minutes, 12 minutes, 13 minutes, 14 minutes, 15 minutes, 16 minutes, 17 minutes, 18 minutes, or 20 minutes.

[0041] Preferably, the drying temperature is 80-100℃, such as 80℃, 82℃, 84℃, 86℃, 88℃, 90℃, 92℃, 94℃, 96℃ or 100℃.

[0042] Preferably, the coating thickness in step (2) is controlled between 0.05 and 0.15 mm, such as 0.05 mm, 0.06 mm, 0.07 mm, 0.08 mm, 0.09 mm, 0.1 mm, 0.11 mm, or 0.15 mm.

[0043] Preferably, the drying temperature in step (2) is 80-120℃ (e.g., 80℃, 85℃, 90℃, 95℃, 100℃, 105℃, 110℃, 115℃ or 120℃, etc.), and the drying time is 10-20min (e.g., 10min, 11min, 12min, 13min, 14min, 15min, 16min, 17min, 18min or 20min, etc.).

[0044] Preferably, step (3) involves compaction by a pressure roller at a pressure of 0.3-0.5 MPa (e.g., 0.3 MPa, 0.35 MPa, 0.4 MPa, 0.45 MPa, or 0.5 MPa) to ensure tight bonding between the layers. Subsequently, the layers are cut according to the preset dimensions of the photovoltaic module, and after passing inspection, they are vacuum-packed to obtain the finished photovoltaic module high-insulation edge-sealing tape.

[0045] The tape of this invention comprises, from top to bottom, insulating fiberglass cloth modified silicone rubber, a modified pressure-sensitive adhesive layer, and a release film layer. After physical, chemical, or blending modification, the insulating fiberglass cloth and insulating rubber retain their lightweight and corrosion-resistant advantages. The composite insulating substrate, reinforced by fiberglass cloth and synergistically modified with silicone rubber, retains these advantages while also possessing excellent electrical insulation properties (dielectric strength ≥35kV / mm, volume resistivity ≥10). 14 The tape boasts excellent thermal conductivity (Ω·cm), wide temperature range adaptability (-50℃ to 200℃, e.g., -50℃, -25℃, 0℃, 25℃, 50℃, 75℃, 100℃, 125℃, 150℃, or 200℃), and superior mechanical properties (tensile strength ≥9.0MPa, elongation at break ≥500%). The pressure-sensitive adhesive layer is modified by introducing UV absorbers, effectively improving the tape's yellowing resistance and enhancing its adhesion and compatibility with photovoltaic module substrates. This tape can be widely used in various photovoltaic modules, maintaining stable insulation and sealing performance in harsh environments, eliminating current leakage and short-circuit risks, extending module lifespan to over 30 years, and significantly improving the reliability and safety of photovoltaic systems.

[0046] On the other hand, the present invention provides the application of the edge-sealing tape for photovoltaic modules as described above in the encapsulation of photovoltaic modules.

[0047] Compared with the prior art, the present invention has the following beneficial effects: (1) Excellent insulation performance: The dielectric strength of the composite insulating substrate of the present invention is ≥35kV / mm and the volume resistivity is ≥10. 14 It has an insulation strength of Ω·cm and its insulation performance is unaffected by temperature and frequency changes. It can effectively isolate the conductive parts of photovoltaic modules, eliminate the risk of current leakage and short circuit, and is compatible with high-voltage photovoltaic modules.

[0048] (2) Strong adaptability to extreme environments: The sealing tape of the present invention has a wide long-term operating temperature range of -50℃ to 200℃ (e.g., -50℃, -25℃, 0℃, 25℃, 50℃, 75℃, 100℃, 125℃, 150℃ or 200℃, etc.), which can withstand extreme environments such as high-temperature deserts, frigid regions, and high-altitude strong ultraviolet radiation. At the same time, it has excellent ozone resistance (200pphm, 40℃, no cracking after 72h), salt spray resistance and chemical corrosion resistance, and its service life can be extended to more than 30 years.

[0049] (3) Excellent mechanical properties: The edge sealing tape of the present invention has a tensile strength ≥9.0MPa, an elongation at break ≥500%, and a tear strength ≥25N / mm. It combines rigid support and elastic buffering capacity, and can withstand the impact of external forces during the installation and transportation of photovoltaic modules, and is not easily damaged.

[0050] (4) Long-term stable bonding and sealing: The modified acrylic pressure-sensitive adhesive has excellent UV aging resistance. The peel strength with various component substrates such as aluminum alloy, glass, TPT backsheet, and fluoropolymer backsheet is ≥1.8N / mm. It has strong adhesion and no peeling or cracking during long-term use. The water-blocking and sealing effect is long-lasting.

[0051] (5) Wide range of applications: The sealing tape of the present invention can be adapted to various photovoltaic modules such as crystalline silicon photovoltaic modules, thin-film photovoltaic modules, BIPV modules, and photovoltaic modules for high-temperature environments, and is especially suitable for photovoltaic power plants in extreme environments. Using this tape can significantly reduce the failure rate and operation and maintenance costs of photovoltaic modules, and improve the overall reliability and economy of photovoltaic systems.

[0052] (6) To address the shortcomings of single substrate performance, this invention adopts a composite design concept of "rigid reinforcement + elastic matrix" to organically combine insulating fiberglass cloth with modified silicone rubber to achieve complementary performance. Attached Figure Description

[0053] Figure 1 This is a schematic diagram of the structure of the sealing tape for photovoltaic modules of the present invention, wherein 1 is an insulating fiberglass cloth layer, 2 is a silicone rubber layer, 3 is a pressure-sensitive adhesive layer, and 4 is a release film layer. Detailed Implementation

[0054] The technical solution of the present invention will be further illustrated below through specific embodiments. Those skilled in the art should understand that the embodiments described are merely illustrative of the present invention and should not be construed as limiting the invention.

[0055] Example 1 Composition of high-insulation sealing tape for photovoltaic modules Composite insulating substrate layer: made of alkali-free fiberglass cloth (100g / m²) 2 The coating is composed of a 0.2mm thick layer of silicone rubber and modified methyl vinyl silicone rubber (Hesheng Silicon Industry MVQ-110 80wt%; Hubei Huifu HL-200 fumed silica 15wt%; KZO Nobel Trigonox® B di-tert-butyl peroxide 3wt%; Rianlon RIANOX® 1010 2wt%), with a coating weight of 80g / m². 2 The substrate thickness after curing is 0.3mm; Raw materials for the preparation of modified acrylate pressure-sensitive adhesive layer: Shimei Chemical PS8541 acrylic copolymer 78wt%, Rianlon: RIANOX® 1010 2wt%, BASF Tinuvin® 770 1.5wt%, Wanhua Chemical HT-100TDI trimer 2.5wt%, Shandong Silicon Science CG-V171 coupling agent 1wt%, solvent ethyl acetate (EAC) 15%, thickness 0.1mm; Release film layer: 36μm silicone-coated polyester film HMX30T10 is selected.

[0056] Preparation method Pretreatment of fiberglass cloth: Immerse the alkali-free fiberglass cloth in a 2wt% KH-560 aqueous solution for 15 minutes, and then dry it in an oven at 90℃. Preparation of modified silicone rubber: Mix the raw materials according to the above formula ratio, put them into a high-speed stirring device and stir at a speed of 1200r / min for 40min, and then perform vacuum degassing treatment to obtain modified silicone rubber solution; Dip-coating and curing: The modified silicone rubber solution is uniformly dipped into the surface of the pretreated fiberglass cloth and then placed in an oven at 140°C for 20 minutes to cure, thereby obtaining a composite insulating substrate. Adhesive coating: Mix the adhesive raw materials according to the formula, apply them to the surface of the composite insulating substrate using a microgravure coating process, and then dry them in an oven at 100°C for 15 minutes. Composite slitting: The composite substrate coated with adhesive layer is laminated with release film, and after being compacted by pressure rollers, it is slitted into finished products with a width of 50mm.

[0057] Example 2 Composition of high-insulation sealing tape for photovoltaic modules Composite insulating substrate layer: made of alkali-free fiberglass cloth (80g / m²) 2 The coating is composed of PVMQ (75wt% Anhui Aiyota IOTA3120 (18% phenyl) + nano silica 20wt% Fujian Yuanxiang New Material YX-200HM + silazane crosslinking agent Hubei Tuoyuan: HMDS 4wt% + antioxidant 168 1wt% Lianlong LONGLIAO 168), with a coating weight of 60g / m². 2 The thickness of the substrate after curing is 0.25mm; Modified acrylic pressure-sensitive adhesive layer: The formulation is the same as in Example 1, with a thickness of 0.08 mm; Release film layer: 40μm PP release film is selected.

[0058] Preparation method The preparation method is basically the same as in Example 1, with only slight adjustments to some process parameters, as follows: for fiberglass cloth pretreatment, the soaking time is 12 min and the drying temperature is 85℃; the stirring speed of the modified silicone rubber is 1300 r / min and the stirring time is 35 min; the dip-coating curing temperature is 130℃ and the curing time is 25 min; the adhesive drying temperature is 95℃ and the drying time is 18 min.

[0059] Example 3 Composition of high-insulation sealing tape for photovoltaic modules Composite insulating substrate layer: made of alkali-free fiberglass cloth (110g / m²) 2 The coating is composed of a 0.10mm thick layer of PVMQ (PVMQ470 + PVMQ75wt% Dongyue Fluorosilicone + PVMQ470 ... 2 The thickness of the substrate after curing is 0.25mm; Modified acrylic pressure-sensitive adhesive layer: Zongyan Chemical PS-77302 acrylic copolymer 85wt%, antioxidant 168 (LONGLIAO 168) 1wt%, BASF Tinuvin® 477 1.0wt%, Jiangsu Sanmu Group triglycidyl isocyanate 2.5wt%, Hangzhou Jessica γ-aminopropyltriethoxysilane 0.5wt%, solvent butyl acetate (BAC) 10%, thickness 0.08mm; Release film layer: 75μm silicone-coated polyester film HMX30T10 is selected.

[0060] Preparation method The preparation method is basically the same as in Example 1, with only slight adjustments to some process parameters, as follows: for fiberglass cloth pretreatment, the soaking time is 8 min and the drying temperature is 100℃; the stirring speed of the modified silicone rubber is 1500 r / min and the stirring time is 20 min; the dip-coating curing temperature is 130℃ and the curing time is 15 min; the adhesive drying temperature is 120℃ and the drying time is 12 min.

[0061] Example 4 Composition of high-insulation sealing tape for photovoltaic modules Composite insulating substrate layer: made of alkali-free fiberglass cloth (80g / m²) 2The coating is composed of PVMQ (73wt% Hubei Longsheng Sihai SH-5202N + 24wt% nano silica Huifu A-200L + 2% Jiangsu Qiangsheng Functional Chemical DCP-995 + 1wt% antioxidant 168 LONGLIAO 168), with a coating weight of 80g / m². 2 The thickness of the substrate after curing is 0.20 mm; Modified acrylic pressure-sensitive adhesive layer: Changxing Chemical EC-7705R acrylic copolymer 75wt%, antioxidant 168 1wt%, LONGLIAO 168 1.5wt%, BASF Tinuvin® 477 1.0wt%, Jiangsu Sanmu Group triglycidyl isocyanate 2.5wt%, Hangzhou Jessica γ-aminopropyltriethoxysilane 9wt%, solvent butyl acetate (BAC) 10%, thickness 0.08mm; Release film layer: 75μm silicone-coated polyester film HMX30T10 is selected.

[0062] Preparation method The preparation method is basically the same as in Example 1, with only slight adjustments to some process parameters, as follows: for fiberglass cloth pretreatment, the soaking time is 8 min and the drying temperature is 100℃; the stirring speed of the modified silicone rubber is 1500 r / min and the stirring time is 20 min; the dip-coating curing temperature is 130℃ and the curing time is 15 min; the adhesive drying temperature is 120℃ and the drying time is 12 min.

[0063] Comparative Example 1 The only difference from Example 1 is that alkali-free fiberglass cloth (100g / m²) is used. 2 The composite material is made of ordinary dimethyl silicone rubber (low methyl content, no vinyl active sites) and precipitated silica (0.2mm thickness) and ordinary dimethyl silicone rubber (low methyl content, no vinyl active sites). The compound ratio is as follows: ordinary dimethyl silicone rubber (Hesheng Silicon Industry 101) 80wt%; precipitated silica (Yuanxiang New Materials FXS-160) 15wt%; Akzo Trigonox® B di-tert-butyl peroxide 3wt%; Rianox® 1010 antioxidant 2wt%; coating weight 80g / m². 2 The substrate thickness after curing is 0.3mm.

[0064] Comparative Example 2 Compared with Example 1, the only difference is that the isocyanate crosslinking agent HT-100 is removed from the pressure-sensitive adhesive formulation, and the amount of acrylic copolymer is changed to 80.5%.

[0065] Comparative Example 3 The composite insulating substrate layer, release film layer, and other pressure-sensitive adhesive raw materials, their proportions, solvent ratios, and dry adhesive thickness are all completely consistent with those in Example 1; only the amount of Wanhua Chemical HT-100 TDI trimer is adjusted from 2.5wt% to 15wt%, and the corresponding amount of acrylic copolymer is reduced to 67wt%.

[0066] The adhesive tapes prepared in the above examples and comparative examples were subjected to performance tests, and the test methods are as follows: (1) Insulation performance test Breakdown voltage test (refer to GB / T 1408.1-2022 "Electrical strength test methods for insulating materials - Part 1: Tests at power frequency"); Test sample: Cut a 10mm×100mm sample from the finished tape, remove the release film, and attach the pressure-sensitive adhesive layer to a clean aluminum plate (ensure no bubbles or wrinkles) as the lower electrode; the upper electrode is a 25mm diameter circular copper electrode (with rounded edges to avoid electric field concentration).

[0067] Test conditions: ambient temperature 23℃±2℃, relative humidity 50%±5%; using the "step-by-step voltage increase method", the initial voltage is 5kV, the voltage is increased by 2kV at each step, and the dwell time at each step is 1min, until the sample breaks down, and the voltage value at the moment of breakdown is recorded; repeat the test 5 times, and take the average value as the final breakdown voltage (unit: kV / mm, which needs to be converted to "voltage / substrate thickness").

[0068] Insulation resistance test (refer to GB / T 1410-2006 "Test methods for volume resistivity and surface resistivity of solid insulating materials") Test sample: Cut a 50mm×50mm sample, remove the release film, and then attach it to a polished stainless steel plate (surface resistivity <10). 4 Ω), using a three-electrode system (main electrode diameter 20mm, protective electrode inner diameter 25mm, outer electrode outer diameter 50mm), the electrode is in close contact with the sample surface (applying 0.1MPa pressure).

[0069] Test conditions: ambient temperature 23℃±2℃, relative humidity 50%±5%; apply 500V DC voltage, let stand for 1 minute and then read the insulation resistance value. Calculate the volume resistivity (unit: Ω·cm) according to the formula "volume resistivity ρv=R×S / d" (R is insulation resistance, S is the area of ​​the main electrode, and d is the thickness of the substrate).

[0070] (2) Weather resistance test Ultraviolet aging test (refer to GB / T 16422.3-2022 "Laboratory Light Source Exposure Test Methods for Plastics - Part 3: Fluorescent Ultraviolet Lamps") Test sample: Cut a 50mm×150mm sample, retain half of the release film (as a blank control), and after removing the release film from the other half, attach it to the aluminum alloy frame commonly used in photovoltaic modules (surface pretreatment: wipe with alcohol to remove oil).

[0071] Test conditions: UVA-340 lamp tube (simulating outdoor ultraviolet light, wavelength 280~400nm, irradiance 0.71W / (m²)) was used. 2 •nm)); Execute “Cyclic Mode”: 8h UV irradiation (temperature 60℃±3℃, no condensation) + 4h dark condensation (temperature 50℃±3℃, relative humidity 95%±5%), for a total of 1000h of testing.

[0072] Test items: ① Yellowing index: The yellowing index of the samples before and after aging was tested using a colorimeter (CIE LAB system). , , Value, calculate the yellowing index ② Adhesion strength decay: After aging, test the peel strength between the tape and the aluminum alloy frame, and calculate the decay rate (decay rate = (initial peel strength - peel strength after aging) / initial peel strength × 100%).

[0073] High and low temperature cycling test (refer to IEC 61215-2:2021 "Design qualification and type approval of terrestrial crystalline silicon photovoltaic modules - Part 2: Test procedures") Test sample: The tape was applied to a photovoltaic module simulation piece (a composite structure of glass + encapsulating film + backsheet) to make a 100mm×100mm test piece with complete edge sealing.

[0074] Test conditions: Perform a "-40℃~120℃ cycle" in a high and low temperature chamber: ① Low temperature stage: -40℃±2℃, hold for 2 hours; ② Heating stage: rise to 120℃±2℃ at a rate of 10℃ / min; ③ High temperature stage: 120℃±2℃, hold for 2 hours; ④ Cooling stage: drop to -40℃ at a rate of 10℃ / min, complete 1 cycle, and accumulate 50 cycles.

[0075] Judgment criteria: After cycling, disassemble the test piece and observe that the tape is free from cracks and peeling, and that the bonding surface is free from bubbles and moisture penetration; retest the insulation resistance to be ≥10 ohms. 12 Ω·cm, peel strength ≥1.2N / mm (initial value ≥1.5N / mm).

[0076] (3) Adhesion performance test Peel strength test (refer to GB / T 2792-2014 "Adhesives 180° Peel Strength Test Method") Test sample: Cut a 25mm×200mm tape sample, remove the release film, and attach the pressure-sensitive adhesive layer to the commonly used substrates of photovoltaic modules (aluminum alloy frame, tempered glass, TPT backsheet). Roll the sample back and forth 3 times with a 2kg roller at a speed of 300mm / min. Test after 24 hours at room temperature.

[0077] Test conditions: tensile testing machine speed 300mm / min ± 10mm / min, test angle 180°, record the maximum force value during the peeling process, and take the average value of 5 tests (unit: N / mm).

[0078] (4) Water-blocking performance test Water vapor transmission rate test (refer to GB / T 1037-2021 "Determination of water vapor transmission rate of plastic films and sheets - cup method") Test sample: Cut a 70mm diameter sample (remove the release film), seal it in the test chamber of the permeation cup (the test chamber is filled with anhydrous calcium chloride, relative humidity 0%), and place the permeation cup in an environment with a temperature of 38℃±1℃ and a relative humidity of 90%±2%.

[0079] Test procedure: Initially weigh the total mass of the permeation cup (m0), then weigh it once every 24 hours (m). n ), continuously tested for 7 days, according to the formula "Water vapor transmission rate WVT=(m n The transmittance (unit: g / (m²)) is calculated using the formula: -m0) / (A×t)" where A is the effective area of ​​the sample and t is the testing time. 2 ·24h).

[0080] The test results are shown in the table below.

[0081] Table 1 The applicant declares that this invention illustrates the photovoltaic module sealing tape, its preparation method, and its application through the above embodiments. However, this invention is not limited to the above embodiments, meaning that this invention does not necessarily rely on the above embodiments for implementation. Those skilled in the art should understand that any improvements to this invention, equivalent substitutions of the raw materials used, additions of auxiliary components, and selection of specific methods all fall within the protection and disclosure scope of this invention.

Claims

1. A sealing tape for photovoltaic modules, characterized in that, The edge-sealing tape for the photovoltaic module comprises, from top to bottom, an insulating fiberglass cloth, a modified silicone rubber layer, a modified pressure-sensitive adhesive layer, and a release film layer.

2. The edge-sealing tape for photovoltaic modules according to claim 1, characterized in that, The insulating fiberglass cloth is alkali-free fiberglass cloth; Preferably, the modified silicone rubber comprises the following components: a silicone rubber matrix, inorganic reinforcing fillers, a crosslinking agent, and an antioxidant; Preferably, the silicone rubber matrix comprises at least one of methyl vinyl silicone rubber or phenyl silicone rubber; Preferably, the inorganic reinforcing filler includes at least one of nano-silica or fumed silica; Preferably, the crosslinking agent is a peroxide-based crosslinking agent, an addition vulcanization system, or a hydrogen-containing silicone oil; Preferably, the peroxide crosslinking agent comprises any one or a combination of at least two of 2,5-dimethyl-2,5-bis(tert-butylperoxy)hexane(bis2,5)peroxide dicumylbenzene or tert-butylisopropylbenzene peroxide; Preferably, the hydrogen-containing silicone oil includes methyl hydrogen-containing silicone oil or phenyl hydrogen-containing silicone oil; Preferably, the antioxidant is one or a combination of at least two of the following: aromatic amine antioxidants, hindered phenolic antioxidants, and auxiliary antioxidants; Preferably, the modified silicone rubber comprises the following components by weight percentage: 70%-90 wt% silicone rubber matrix, 10%-20 wt% inorganic reinforcing filler, 2%-5 wt% crosslinking agent, and 0.5%-1 wt% antioxidant; Preferably, the thickness of the modified silicone rubber layer is 0.2-0.5 mm.

3. The edge-sealing tape for photovoltaic modules according to claim 1 or 2, characterized in that, The raw materials for preparing the modified pressure-sensitive adhesive layer include the following components in parts by weight: 100 parts of solvent-based pressure-sensitive adhesive Crosslinking agent 0.2-10 parts Antioxidant 0-10 parts 0.5 to 5 parts of ultraviolet absorber 5-30 parts of tackifying resin Coupling agent 0.1-5 parts Organic solvents: 0-60 parts.

4. The edge-sealing tape for photovoltaic modules according to claim 3, characterized in that, The solvent-based pressure-sensitive adhesive is selected from one or a mixture of at least two of the following: polyurethane pressure-sensitive adhesive, silicone pressure-sensitive adhesive, acrylic pressure-sensitive adhesive, natural rubber-based pressure-sensitive adhesive, and synthetic rubber-based pressure-sensitive adhesive. Preferably, the crosslinking agent is any one or a combination of at least two of epoxy crosslinking agents, isocyanate crosslinking agents, organic peroxides, and metal oxides; Preferably, the antioxidant is one or a combination of at least two of the following: aromatic amine antioxidants, hindered phenolic antioxidants, and auxiliary antioxidants; Preferably, the ultraviolet absorber is selected from one or a mixture of at least two of the following: salicylates, benzophenones, benzimidazoles, substituted acrylonitriles, and triazine compounds with hindered amines; Preferably, the tackifying resin is one or a combination of at least two of the following: rosin resin, modified rosin resin, terpene resin, and synthetic petroleum resin. Preferably, the coupling agent is any one or a combination of at least two of vinyltrimethoxysilane, vinyltriethoxysilane, vinyltri(β-methoxyethoxy)silane, N-(2-aminoethyl-3-aminopropyl)trimethoxysilane, 3-(2,3-epoxypropoxy)propylmethyldiethoxysilane, 3-(methacryloylchloro)propyltrimethoxysilane, or γ-methacryloyloxypropyltrimethoxysilane; Preferably, the organic solvent is selected from any one or a combination of at least two of ethyl acetate, n-butyl acetate, isopropyl acetate, sec-butyl acetate, acetone, butanone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, toluene, and xylene; Preferably, the thickness of the pressure-sensitive adhesive layer is 0.05 to 0.15 mm.

5. The edge-sealing tape for photovoltaic modules according to any one of claims 1-4, characterized in that, The release film layer is a release film coated with silicone or fluorine release agent, and the substrate is a polyester film or a PP release film.

6. The method for preparing the edge-sealing tape for photovoltaic modules according to any one of claims 1-5, characterized in that, The preparation method includes the following steps: (1) The modified silicone rubber liquid is uniformly coated on the surface of the insulating fiberglass cloth and cured to obtain the modified silicone rubber layer of the insulating fiberglass cloth; (2) The modified pressure-sensitive adhesive is coated on the surface of the modified silicone rubber layer of insulating fiberglass cloth and dried to obtain the modified pressure-sensitive adhesive layer; (3) The material obtained in step (2) is combined with the release film to obtain the sealing tape for the photovoltaic module.

7. The preparation method according to claim 6, characterized in that, The modified silicone rubber solution in step (1) is obtained by mixing the raw material components of the modified silicone rubber and then performing vacuum degassing treatment; Preferably, the mixing is performed by stirring at a speed of 1000-1500 r / min for 30-60 min; Preferably, the amount of coating in step (1) is 50-100 g / m 2 ; Preferably, the curing temperature in step (1) is 120-160℃ and the curing time is 10-30min.

8. The preparation method according to claim 6, characterized in that, The insulating fiberglass cloth undergoes pretreatment before use, which includes the following steps: Fiberglass cloth is immersed in an aqueous solution of silane coupling agent and then dried to obtain surface-modified fiberglass cloth. Preferably, the basis weight of the fiberglass cloth is 50-150 g / m². 2 The thickness is 0.1-0.3mm; Preferably, the silane coupling agent is any one or a combination of at least two of vinyltrimethoxysilane, vinyltriethoxysilane, vinyltri(β-methoxyethoxy)silane, N-(2-aminoethyl-3-aminopropyl)trimethoxysilane, 3-(2,3-epoxypropoxy)propylmethyldiethoxysilane, 3-(methacryloylchloro)propyltrimethoxysilane, or γ-methacryloyloxypropyltrimethoxysilane; Preferably, the concentration of the aqueous solution of the silane coupling agent is 1%-3wt%; Preferably, the soaking time is 10-20 minutes; Preferably, the drying temperature is 80-100℃.

9. The preparation method according to claim 6, characterized in that, The coating thickness in step (2) is controlled to be 0.05-0.15 mm; Preferably, the drying temperature in step (2) is 80-120℃ and the drying time is 10-20 min; Preferably, step (3) is compounding by compaction with a pressure roller, the pressure of which is 0.3-0.5 MPa.

10. The application of the edge-sealing tape for photovoltaic modules according to any one of claims 1-5 in the encapsulation of photovoltaic modules.

Images