Insulating glue based on ultraviolet curing as well as preparation method and application of insulating glue

Abstract

The invention discloses insulating glue based on ultraviolet curing as well as a preparation method and application of the insulating glue. The insulating glue is prepared from the following raw materials in percentage by mass: 35 to 60 percent of modified polyurethane epoxy acrylate resin, 1 to 10 percent of photoinitiator, 5 to 20 percent of reactive diluent, 20 to 60 percent of inorganic filler and 1 to 4 percent of additive. The modified polyurethane epoxy acrylate resin is adopted in the insulating glue, so that a cured coating has better adhesive force and water resistance, higher hardness and lower warpage, lower cost is realized, and various standards in actual application can be met.

Description

Technical Field

[0001] The present invention relates to the technical field of photovoltaic cell sheet insulation coatings, and in particular to an insulation adhesive based on ultraviolet light curing, and a preparation method and application thereof. Background Art

[0002] With the acceleration of the carbon neutrality process, the cost of photovoltaic power generation continues to decline, technology continues to advance, and power generation efficiency continues to break through. As the main force of renewable clean energy, photovoltaic new energy has become an important support for achieving global energy transformation and green development. Photovoltaic cells are devices that convert light energy into electrical energy through the photovoltaic effect, and their core lies in the battery cell.

[0003] The output voltage of a single solar cell is only 0.5-0.7V, so multiple cells need to be welded in series to output the rated voltage. There are many hidden dangers in the process of cell welding, such as cold welding and over-welding. The use of insulating coating can effectively protect the electrode, ensure the battery yield and finished product quality during the production process, and ultraviolet light rapid curing is not only suitable for production line operation, but also helps to reduce production costs.

[0004] In view of the cell production process and actual application scenarios, the insulating coating needs to meet the following requirements: 1) Good insulation (volume resistivity ≥ 4×10 16 Ω·cm), to prevent short circuit during welding; 2) Good adhesion to the battery cell, film hardness ≥5H (Chinese hardness pencil, 750g load), to avoid damage to the coating during spot welding; 3) Resistant to high temperature and high humidity environment, to prevent carbonization damage to the coating caused by high temperature during welding and shortening of battery life caused by subsequent water vapor intrusion; 4) Low curing shrinkage rate, to avoid excessive warping of the battery cell; 5) Under 110-250 mesh screen printing conditions, there are almost no bubbles and shrinkage holes after the coating is cured.

[0005] The reliability of insulating adhesive greatly affects the service life of photovoltaic cells. Most insulating adhesives on the market are difficult to meet the requirements of strong adhesion, high hardness, and low warpage. Insulating adhesives with high-functionality oligomers as the main body often have higher hardness, but large curing shrinkage. Insulating adhesives with low-functionality oligomers as the main body have smaller curing shrinkage, but lower hardness. In addition, the degree of curing, adhesion, and surface hydrophobicity of the coating have a great influence on the heat resistance and water vapor resistance of the film. Therefore, it is very necessary to develop a UV-curable insulating adhesive that meets the above requirements, reducing the cost of raw materials while ensuring production efficiency and product quality. Summary of the invention

[0006] In view of the above problems existing in the prior art, the present invention provides an insulating adhesive based on UV curing and a preparation method and application thereof. The insulating adhesive of the present invention adopts a modified polyurethane epoxy acrylate resin, so that the cured coating has better adhesion and water resistance, higher hardness and lower warping, achieving lower cost while meeting the above standards in practical application.

[0007] The technical solution of the present invention is as follows:

[0008] The first object of the present invention is to provide an insulating adhesive based on ultraviolet light curing, wherein the raw materials of the insulating adhesive are as follows: each raw material is calculated by mass percentage.

[0009]

[0010] Wherein, the modified polyurethane epoxy acrylate resin is prepared by the following method: each raw material is calculated by mass percentage;

[0011] Mix 30-50% polyurethane epoxy resin and 10-40% acrylic acid, heat to 80-90°C, disperse for 1-2 hours until completely dissolved after the temperature stabilizes, then add 0.1-10% catalyst and 0.1-10% inhibitor, and stir for 20-30 minutes;

[0012] Then add 8-15% active monomer, and raise the temperature to 100-110°C to react for 10-12 hours;

[0013] When the acid value is less than 5, 1-8% hydrogen-containing silicone oil is added, and the mixture is dispersed and stirred at 95-100° C. for 3-6 hours and then cooled to obtain the modified polyurethane epoxy acrylate resin.

[0014] In one embodiment of the present invention, the polyurethane epoxy resin is one or more of 102C-1 and 102C-1H of Taizhou Hengchuang Insulation Materials Co., Ltd., DER852 and DER791 of Dow Olin Company of the United States, SZ-2360 of Wuhan Shiquanxing New Materials Technology Co., Ltd., and EPU-133 and EPU-133L of Luohe High-tech Materials (Shanghai) Co., Ltd.

[0015] In one embodiment of the present invention, the catalyst is one or more of hydrochloric acid, sulfuric acid, phosphoric acid, and metal salts; the inhibitor is one or more of hydroquinone, p-hydroxyanisole, methylhydroquinone, and 2-tert-butylhydroquinone; and the active monomer is an acrylate monomer.

[0016] In one embodiment of the present invention, the active monomer is one or more of EOEOEA, CTFA, and THFA.

[0017] In one embodiment of the present invention, the hydrogen-containing silicone oil is a terminal hydrogen-containing silicone oil ( EH4000, EH8000), side hydrogen silicone oil ( SHS018A), end side multi-hydrogen silicone oil ( MHS01, MHS05) or more.

[0018] Preferably, the hydrogen-containing silicone oil is one or more of terminal hydrogen-containing silicone oil and terminal multi-hydrogen-containing silicone oil.

[0019] Preferably, the hydrogen-containing silicone oil is EH4000, One or more of MHS01.

[0020] In one embodiment of the present invention, the photoinitiator is one or more of phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide (819), 2-phenylbenzyl-2-dimethylamine-1-(4-morpholinobenzylphenyl)butanone (369), 1-hydroxy-cyclohexyl-phenyl ketone (184), benzoin diethyl ether (651), benzophenone (BP), 2-hydroxy-2-methyl-1-phenyl-1-propanone (1173), 2,4,6(trimethylbenzoyl)diphenylphosphine oxide (TPO), ethyl 2,4,6-trimethylbenzoylphosphonate (TPO-L), and 2-methyl-1-[4-methylthiophenyl]-2-morpholino-1-propanone (907).

[0021] In one embodiment of the present invention, the reactive diluent is one or more of monofunctional, difunctional, and multifunctional acrylates.

[0022] Preferably, the active diluent is one or more of DCPA, EOEOEA, CTFA, THFA, IBOA, THFMA, HDDA, DEGDMA, and DPHA.

[0023] In one embodiment of the present invention, the inorganic filler is one or more of barium sulfate, silicon powder, gas silica, talc, calcium carbonate, and wax powder.

[0024] In one embodiment of the present invention, the auxiliary agent is one or more of 2,2-(4,4-distyryl)bisbenzoxazole, 2,5-bis(5-tert-butyl-benzoxazole-2-yl)thiophene, 2-methylimidazole, 2-ethyl-4-methylimidazole, hydroquinone, γ-methacryloxypropyltrimethoxysilane, KS-66, and BYK-405.

[0025] Preferably, the auxiliary agent is one or more of 2,2-(4,4-diphenylethylene)bisbenzoxazole, γ-methacryloxypropyltrimethoxysilane, and KS-66.

[0026] The second object of the present invention is to provide a method for preparing the above-mentioned UV-curable insulating adhesive, comprising the following steps:

[0027] 35-60% of modified polyurethane epoxy acrylate resin, 1-10% of photoinitiator, 5-20% of active diluent, 1-4% of auxiliary agent and 20-60% of inorganic filler are added in sequence and dispersed evenly, then ground by a hydraulic three-roll mill until the particle fineness is less than 15 μm, the viscosity is adjusted to 5-8 Pa·s, and filtered to obtain the insulating adhesive.

[0028] The third object of the present invention is to provide an application of the above-mentioned UV-curable insulating adhesive on photovoltaic cells, using 110-250 mesh screen printing to form an insulating coating on the cell, the coating thickness is 10-30 μm, and then the LED light source is used for exposure and curing, and the exposure energy is 10000±1000mj / cm 2 .

[0029] The beneficial technical effects of the present invention are:

[0030] The modified polyurethane epoxy acrylate resin used in the insulating glue of the present invention enables the insulating coating to have the characteristics of heat shock resistance, high temperature water vapor resistance, good adhesion, high hardness and low warping; at the same time, it solves the bubble problem that is easy to occur in rapid printing on the production line, and improves the reliability of the coating. DETAILED DESCRIPTION

[0031] The present invention will be described in detail below in conjunction with the embodiments.

[0032] Example 1

[0033] A method for preparing a modified polyurethane epoxy acrylate resin is as follows:

[0034] Add 50% EPU-133L resin to a three-necked flask containing 35% acrylic acid, heat to 90°C, disperse for 1 hour until completely dissolved after the temperature stabilizes, then add 0.4% phosphoric acid and 0.6% p-hydroxyanisole, stir for 30 minutes, then add 12% active monomer THFA, heat to 105°C and react for 10 hours. When the acid value is less than 5, add 2% MHS01, maintain 100℃ for 4 hours of dispersion and stirring, then cool down to obtain modified polyurethane epoxy acrylate resin GXE-2%.

[0035] A method for preparing an insulating adhesive based on ultraviolet light curing comprises the following steps:

[0036] 50% of the modified polyurethane epoxy acrylate resin, 5% of the photoinitiator TPO, 15% of the active diluent CTFA, 2% of the auxiliary agent, and 28% of the inorganic filler are added in sequence and dispersed evenly, then ground by a hydraulic three-roll mill until the particle fineness is less than 15 μm, the viscosity is adjusted to 5-8 Pa·s, and the insulating adhesive is obtained after filtering.

[0037] A 30 μm (thickness) uniform coating was formed on the cell by screen printing, and then irradiated with 395 nm LED ultraviolet light with an energy of 10000 ± 1000 mj / cm 2 .

[0038] Example 2

[0039] A method for preparing a modified polyurethane epoxy acrylate resin is as follows:

[0040] Add 50% EPU-133L resin to a three-necked flask containing 35% acrylic acid, heat to 90°C, disperse for 1 hour until completely dissolved after the temperature stabilizes, then add 0.4% phosphoric acid and 0.6% p-hydroxyanisole, stir for 30 minutes, then add 10% active monomer THFA, heat to 105°C and react for 10 hours. When the acid value is less than 5, add 4% MHS01, maintain 100℃ for 4 hours of dispersion and stirring, then cool down to obtain modified polyurethane epoxy acrylate resin GXE-4%.

[0041] A method for preparing an insulating adhesive based on ultraviolet light curing comprises the following steps:

[0042] 50% of the modified polyurethane epoxy acrylate resin, 5% of the photoinitiator TPO, 15% of the active diluent CTFA, 2% of the auxiliary agent, and 28% of the inorganic filler are added in sequence and dispersed evenly, then ground by a hydraulic three-roll mill until the particle fineness is less than 15 μm, the viscosity is adjusted to 5-8 Pa·s, and the insulating adhesive is obtained after filtering.

[0043] A 30 μm (thickness) uniform coating was formed on the cell by screen printing, and then irradiated with 395 nm LED ultraviolet light with an energy of 10000 ± 1000 mj / cm 2 .

[0044] Example 3

[0045] A method for preparing a modified polyurethane epoxy acrylate resin is as follows:

[0046] Add 50% EPU-133L resin to a three-necked flask containing 35% acrylic acid, heat it to 90°C, disperse it for 1 hour until it is completely dissolved after the temperature stabilizes, then add 0.4% phosphoric acid and 0.6% p-hydroxyanisole, stir for 30 minutes, then add 8% active monomer THFA, heat it to 105°C and react for 10 hours. When the acid value is less than 5, add 6% MHS01, maintain 100℃ for 4 hours of dispersion and stirring, then cool down to obtain modified polyurethane epoxy acrylate resin GXE-6%.

[0047] A method for preparing an insulating adhesive based on ultraviolet light curing comprises the following steps:

[0048] 50% modified polyurethane epoxy acrylate resin, 5% photoinitiator TPO, 15% active diluent CTFA, 2% additives, and 28% inorganic filler are added in sequence and dispersed evenly, then ground by a hydraulic three-roll mill until the particle fineness is less than 15 μm, the viscosity is adjusted to 5-8 Pa·s, and filtered to obtain the insulating adhesive.

[0049] A 30 μm (thickness) uniform coating was formed on the cell by screen printing, and then irradiated with 395 nm LED ultraviolet light with an energy of 10000 ± 1000 mj / cm 2 .

[0050] The results of TGA test (ambient conditions 25°C, 62% RH) of the cured coating showed that the temperature when the sample lost 2% of its mass was 268.02°C, and the temperature when the sample lost 5% of its mass was 321.75°C.

[0051] Example 4

[0052] A method for preparing a modified polyurethane epoxy acrylate resin is as follows:

[0053] Add 50% EPU-133L resin to a three-necked flask containing 35% acrylic acid, heat it to 90°C, disperse it for 1 hour until it is completely dissolved after the temperature stabilizes, then add 0.4% phosphoric acid and 0.6% p-hydroxyanisole, stir for 30 minutes, then add 8% active monomer THFA, heat it to 105°C and react for 10 hours. When the acid value is less than 5, add 6% MHS01, maintain 100℃ for 4 hours of dispersion and stirring, then cool down to obtain modified polyurethane epoxy acrylate resin GXE-6%.

[0054] A method for preparing an insulating adhesive based on ultraviolet light curing comprises the following steps:

[0055] 45% modified polyurethane epoxy acrylate resin, 5% photoinitiator TPO, 15% active diluent CTFA, 2% additives, and 33% inorganic filler are added in sequence and dispersed evenly, then ground by a hydraulic three-roll mill until the particle fineness is less than 15 μm, the viscosity is adjusted to 5-8 Pa·s, and filtered to obtain the insulating adhesive.

[0056] A 30 μm (thickness) uniform coating was formed on the cell by screen printing, and then irradiated with 395 nm LED ultraviolet light with an energy of 10000 ± 1000 mj / cm 2 .

[0057] Example 5

[0058] A method for preparing a modified polyurethane epoxy acrylate resin is as follows:

[0059] Add 50% EPU-133L resin to a three-necked flask containing 35% acrylic acid, heat it to 90°C, disperse it for 1 hour until it is completely dissolved after the temperature stabilizes, then add 0.4% phosphoric acid and 0.6% p-hydroxyanisole, stir for 30 minutes, then add 8% active monomer THFA, heat it to 105°C and react for 10 hours. When the acid value is less than 5, add 6% MHS01, maintain 100℃ for 4 hours of dispersion and stirring, then cool down to obtain modified polyurethane epoxy acrylate resin GXE-6%.

[0060] A method for preparing an insulating adhesive based on ultraviolet light curing comprises the following steps:

[0061] 55% modified polyurethane epoxy acrylate resin, 6% photoinitiator TPO, 15% active diluent CTFA, 2% additives, and 22% inorganic filler are added in sequence and dispersed evenly, then ground by a hydraulic three-roll mill until the particle fineness is less than 15 μm, the viscosity is adjusted to 5-8 Pa·s, and filtered to obtain the insulating adhesive.

[0062] A 30 μm (thickness) uniform coating was formed on the cell by screen printing, and then irradiated with 395 nm LED ultraviolet light with an energy of 10000 ± 1000 mj / cm 2 .

[0063] Example 6

[0064] A method for preparing a modified polyurethane epoxy acrylate resin is as follows:

[0065] Add 50% EPU-133L resin to a three-necked flask containing 35% acrylic acid, heat it to 90°C, disperse it for 1 hour until it is completely dissolved after the temperature stabilizes, then add 0.4% phosphoric acid and 0.6% p-hydroxyanisole, stir for 30 minutes, then add 8% active monomer THFA, heat it to 105°C and react for 10 hours. When the acid value is less than 5, add 6% MHS01, maintain 100℃ for 4 hours of dispersion and stirring, then cool down to obtain modified polyurethane epoxy acrylate resin GXE-6%.

[0066] A method for preparing an insulating adhesive based on ultraviolet light curing comprises the following steps:

[0067] 45% modified polyurethane epoxy acrylate resin, 5% photoinitiator 819, 15% active diluent IBOA, 2% auxiliary agent, and 33% inorganic filler are added in sequence and dispersed evenly, then ground by a hydraulic three-roll mill until the particle fineness is less than 15 μm, the viscosity is adjusted to 5-8 Pa·s, and filtered to obtain the insulating adhesive.

[0068] A 30 μm (thickness) uniform coating was formed on the cell by screen printing, and then irradiated with 395 nm LED ultraviolet light with an energy of 10000 ± 1000 mj / cm 2 .

[0069] Example 7

[0070] A method for preparing a modified polyurethane epoxy acrylate resin is as follows:

[0071] Add 50% EPU-133L resin to a three-necked flask containing 35% acrylic acid, heat it to 90°C, disperse it for 1 hour until it is completely dissolved after the temperature stabilizes, then add 0.4% phosphoric acid and 0.6% p-hydroxyanisole, stir for 30 minutes, then add 8% active monomer THFA, heat it to 105°C and react for 10 hours. When the acid value is less than 5, add 6% MHS01, maintain 100℃ for 4 hours of dispersion and stirring, then cool down to obtain modified polyurethane epoxy acrylate resin GXE-6%.

[0072] A method for preparing an insulating adhesive based on ultraviolet light curing comprises the following steps:

[0073] 45% modified polyurethane epoxy acrylate resin, 5% photoinitiator 651, 15% active diluent HDDA, 2% auxiliary agent and 33% inorganic filler are added in sequence and dispersed evenly, then ground by a hydraulic three-roll mill until the particle fineness is less than 15 μm, the viscosity is adjusted to 5-8 Pa·s, and filtered to obtain the insulating adhesive.

[0074] A 30 μm (thickness) uniform coating was formed on the cell by screen printing, and then irradiated with 395 nm LED ultraviolet light with an energy of 10000 ± 1000 mj / cm 2 .

[0075] Example 8

[0076] A method for preparing a modified polyurethane epoxy acrylate resin is as follows:

[0077] Add 50% EPU-133L resin to a three-necked flask containing 35% acrylic acid, heat it to 90°C, disperse it for 1 hour until it is completely dissolved after the temperature stabilizes, then add 0.4% phosphoric acid and 0.6% p-hydroxyanisole, stir for 30 minutes, then add 8% active monomer THFA, heat it to 105°C and react for 10 hours. When the acid value is less than 5, add 6% MHS01, maintain 100℃ for 4 hours of dispersion and stirring, then cool down to obtain modified polyurethane epoxy acrylate resin GXE-6%.

[0078] A method for preparing an insulating adhesive based on ultraviolet light curing comprises the following steps:

[0079] 45% modified polyurethane epoxy acrylate resin, 5% photoinitiator TPO-L, 15% active diluent THFA, 2% additives, and 33% inorganic filler are added in sequence and dispersed evenly, then ground by a hydraulic three-roll mill until the particle fineness is less than 15 μm, the viscosity is adjusted to 5-8 Pa·s, and filtered to obtain the insulating adhesive.

[0080] A 30 μm (thickness) uniform coating was formed on the cell by screen printing, and then irradiated with 395 nm LED ultraviolet light with an energy of 10000 ± 1000 mj / cm 2 .

[0081] Example 9

[0082] A method for preparing a modified polyurethane epoxy acrylate resin is as follows:

[0083] Add 50% 102C-1H resin to a three-necked flask containing 35% acrylic acid, heat to 90°C, disperse for 1 hour until completely dissolved after the temperature stabilizes, then add 0.4% phosphoric acid and 0.6% p-hydroxyanisole, stir for 30 minutes, then add 8% active monomer THFA, heat to 105°C and react for 10 hours. When the acid value is less than 5, add 6% MHS01, maintain the dispersion stirring at 100℃ for 4 hours and then cool down to obtain the modified polyurethane epoxy acrylate resin GXC-6%.

[0084] A method for preparing an insulating adhesive based on ultraviolet light curing comprises the following steps:

[0085] 45% modified polyurethane epoxy acrylate resin, 5% photoinitiator TPO, 15% active diluent CTFA, 2% additives, and 33% inorganic filler are added in sequence and dispersed evenly, then ground by a hydraulic three-roll mill until the particle fineness is less than 15 μm, the viscosity is adjusted to 5-8 Pa·s, and filtered to obtain the insulating adhesive.

[0086] A 30 μm (thickness) uniform coating was formed on the cell by screen printing, and then irradiated with 395 nm LED ultraviolet light with an energy of 10000 ± 1000 mj / cm 2 .

[0087] Example 10

[0088] A method for preparing a modified polyurethane epoxy acrylate resin is as follows:

[0089] Add 50% 102C-1H resin to a three-necked flask containing 35% acrylic acid, heat to 90°C, disperse for 1 hour until completely dissolved after the temperature stabilizes, then add 0.4% phosphoric acid and 0.6% p-hydroxyanisole, stir for 30 minutes, then add 8% active monomer THFA, heat to 105°C and react for 10 hours. When the acid value is less than 5, add 6% MHS01, maintain the dispersion stirring at 100℃ for 4 hours and then cool down to obtain the modified polyurethane epoxy acrylate resin GXC-6%.

[0090] A method for preparing an insulating adhesive based on ultraviolet light curing comprises the following steps:

[0091] 45% modified polyurethane epoxy acrylate resin, 4% photoinitiator 819, 1% photoinitiator 651, 15% active diluent HDDA, 2% auxiliary agent, and 33% inorganic filler are added in sequence and dispersed evenly, then ground by a hydraulic three-roll mill until the particle fineness is less than 15 μm, the viscosity is adjusted to 5-8 Pa·s, and filtered to obtain the insulating adhesive.

[0092] A 30 μm (thickness) uniform coating was formed on the cell by screen printing, and then irradiated with 395 nm LED ultraviolet light with an energy of 10000 ± 1000 mj / cm 2 .

[0093] Comparative Example 1

[0094] A method for preparing an unmodified polyurethane epoxy acrylate resin is as follows:

[0095] Add 50% EPU-133L resin to a three-necked flask containing 35% acrylic acid, heat it to 90°C, disperse it for 1 hour until it is completely dissolved after the temperature stabilizes, then add 0.4% phosphoric acid and 0.6% p-hydroxyanisole, stir for 30 minutes, then add 14% active monomer THFA, heat it to 105°C, react for 12 hours, and then cool it down. Unmodified polyurethane epoxy acrylate resin GXE-0% is obtained.

[0096] A method for preparing an insulating adhesive based on ultraviolet light curing comprises the following steps:

[0097] 50% unmodified polyurethane epoxy acrylate resin, 5% photoinitiator TPO, 15% active diluent CTFA, 2% additives, and 28% inorganic filler are added in sequence and dispersed evenly, then ground by a hydraulic three-roll mill until the particle fineness is less than 15 μm, the viscosity is adjusted to 5-8 Pa·s, and filtered to obtain the insulating adhesive.

[0098] A 30 μm (thickness) uniform coating was formed on the cell by screen printing, and then irradiated with 395 nm LED ultraviolet light with an energy of 10000 ± 1000 mj / cm 2 .

[0099] Comparative Example 2

[0100] A method for preparing a modified polyurethane epoxy acrylate resin is as follows:

[0101] Add 50% EPU-133L resin to a three-necked flask containing 35% acrylic acid, heat it to 90°C, disperse it for 1 hour until it is completely dissolved after the temperature stabilizes, then add 0.4% phosphoric acid and 0.6% p-hydroxyanisole, stir for 30 minutes, then add 8% active monomer THFA, heat it to 105°C and react for 10 hours. When the acid value is less than 5, add 6% MHS01, maintain 100℃ for 4 hours of dispersion and stirring, then cool down to obtain modified polyurethane epoxy acrylate resin GXE-6%.

[0102] A method for preparing an insulating adhesive based on ultraviolet light curing comprises the following steps:

[0103] 30% modified polyurethane epoxy acrylate resin, 3% photoinitiator TPO, 15% active diluent CTFA, 2% additives, and 50% inorganic filler are added in sequence and dispersed evenly, then ground by a hydraulic three-roll mill until the particle fineness is less than 15 μm, the viscosity is adjusted to 5-8 Pa·s, and filtered to obtain the insulating adhesive.

[0104] A 30 μm (thickness) uniform coating was formed on the cell by screen printing, and then irradiated with 395 nm LED ultraviolet light with an energy of 10000 ± 1000 mj / cm2 .

[0105] The types and mass fractions of the insulating adhesive raw materials in the above-mentioned Examples 1 to 5 and Comparative Examples 1 to 2 are listed in Table 1; the types and mass fractions of the insulating adhesive raw materials in Examples 6 to 10 are listed in Table 2:

[0106] Table 1

[0107]

[0108]

[0109] Table 2

[0110]

[0111] The test methods for the performance of the insulating coating are as follows: the hardness test is carried out using a Chinese hardness pencil with a load of 750g; the warpage test is measured using a vernier caliper after UV irradiation; the adhesion is tested using a grid knife and 3M tape; the volume resistivity is tested using a DC high resistance measurement method; the heat resistance test is completed by applying flux on the coating and keeping it in a 300℃ tin furnace for 1 minute; the water vapor resistance test is carried out using high-pressure water boiling for 5 hours; the bubbles are counted by a magnifying glass for 1cm 2 The number of bubbles within the range is evaluated. The test results are listed in Table 3:

[0112] Table 3

[0113]

[0114] As can be seen from Table 3, Examples 1 to 10 using modified polyurethane epoxy acrylate all have excellent performance in hardness, warping, adhesion, insulation, heat resistance, water vapor resistance and bubble tests, indicating that modified polyurethane epoxy acrylate effectively improves the comprehensive performance of the insulating adhesive. Compared with Comparative Example 1, Examples 1 to 3 and Examples 4 to 5 compared with Comparative Example 2, the adhesion and water vapor resistance of the insulating adhesive are poor when unmodified polyurethane epoxy acrylate is used; when the mass fraction of modified polyurethane epoxy acrylate in the insulating adhesive is too low, the hardness, heat resistance and water vapor resistance of the coating cannot meet the standards. In summary, the insulating adhesive based on UV curing in the present invention provides a reliable implementation plan for the insulating coating of photovoltaic cells and has broad application prospects.

[0115] The embodiments provided above are not intended to limit the scope of the present invention, and the steps described are not intended to limit the execution order thereof. Those skilled in the art may make obvious improvements to the present invention in combination with existing common knowledge, which also fall within the scope of protection defined by the claims of the present invention.

Claims

1. An insulating adhesive based on ultraviolet light curing, characterized in that: The raw material composition of the insulating glue is: Wherein, the modified polyurethane epoxy acrylate resin is prepared by the following method: Mix 30-50% polyurethane epoxy resin and 10-40% acrylic acid, heat to 80-90°C, disperse for 1-2 hours until completely dissolved after the temperature stabilizes, then add 0.1-10% catalyst and 0.1-10% inhibitor, and stir for 20-30 minutes; Then add 8-15% active monomer, and raise the temperature to 100-110°C to react for 10-12 hours; When the acid value is less than 5, 1-8% hydrogen-containing silicone oil is added, and the mixture is dispersed and stirred at 95-100° C. for 3-6 hours and then cooled to obtain the modified polyurethane epoxy acrylate resin.

2. The UV-curable insulating adhesive according to claim 1, characterized in that: The polyurethane epoxy resin is one or more of 102C-1 and 102C-1H of Taizhou Hengchuang Insulation Material Co., Ltd., DER852 and DER791 of Dow Olin Company of the United States, SZ-2360 of Wuhan Shiquanxing New Materials Technology Co., Ltd., and EPU-133 and EPU-133L of Luhe High-tech Materials (Shanghai) Co., Ltd.

3. The UV-curable insulating adhesive according to claim 1, characterized in that: The catalyst is one or more of hydrochloric acid, sulfuric acid, phosphoric acid and metal salt; the inhibitor is one or more of hydroquinone, p-hydroxyanisole, methylhydroquinone and 2-tert-butylhydroquinone; and the active monomer is an acrylate monomer.

4. The UV-curable insulating adhesive according to claim 1, characterized in that: The hydrogen-containing silicone oil is one or more of terminal hydrogen-containing silicone oil, side hydrogen-containing silicone oil, and terminal-side multi-hydrogen-containing silicone oil.

5. The UV-curable insulating adhesive according to claim 1, characterized in that: The photoinitiator is one or more of phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide, 2-phenylbenzyl-2-dimethylamine-1-(4-morpholinobenzylphenyl)butanone, 1-hydroxy-cyclohexyl-phenyl ketone, benzoin diethyl ether, benzophenone, 2-hydroxy-2-methyl-1-phenyl-1-propanone, 2,4,6(trimethylbenzoyl)diphenylphosphine oxide, ethyl 2,4,6-trimethylbenzoylphosphonate, and 2-methyl-1-[4-methylthiophenyl]-2-morpholinyl-1-propanone.

6. The UV-curable insulating adhesive according to claim 1, characterized in that: The active diluent is one or more of monofunctional, difunctional and multifunctional acrylates.

7. The UV-curable insulating adhesive according to claim 1, characterized in that: The inorganic filler is one or more of barium sulfate, silicon powder, gas silica, talcum powder, calcium carbonate and wax powder.

8. The UV-curable insulating adhesive according to claim 1, characterized in that: The auxiliary agent is one or more of 2,2-(4,4-distyryl)bisbenzoxazole, 2,5-bis(5-tert-butyl-benzoxazole-2-yl)thiophene, 2-methylimidazole, 2-ethyl-4-methylimidazole, hydroquinone, γ-methacryloxypropyltrimethoxysilane, KS-66, and BYK-405.

9. A method for preparing the UV-curable insulating adhesive according to claim 1, characterized in that: The preparation method comprises the following steps: 35-60% of modified polyurethane epoxy acrylate resin, 1-10% of photoinitiator, 5-20% of active diluent, 1-4% of auxiliary agent and 20-60% of inorganic filler are added in sequence and dispersed evenly, then ground by a hydraulic three-roll mill until the particle fineness is less than 15 μm, the viscosity is adjusted to 5-8 Pa·s, and filtered to obtain the insulating adhesive.

10. An application of the UV-curable insulating adhesive according to claim 1 on a photovoltaic cell, characterized in that: Use 110-250 mesh screen printing to form an insulating coating on the battery cell with a coating thickness of 10-30μm, and then expose and cure it with an LED light source with an exposure energy of 10000±1000mj / cm 2 .

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