Single-component organic silica gel as well as preparation method and application thereof

Abstract

The single-component organic silica gel provided by the invention meets the bonding and fixing requirements of a low-temperature welding strip and meets the lamination requirements. The composition comprises the following components in parts by weight: 15-35 parts of vinyl silicone oil, 20-45 parts of hydrogen-containing silicone oil, 25-55 parts of vinyl MQ resin and 0.05-5 parts of a catalyst. According to the single-component organic silica gel, through a unique catalyst-inhibitor system, good storage stability is guaranteed, and the single-component organic silica gel can be rapidly cured at high temperature to form firm adhesion. The cured organic silica gel is high in light transmittance, and the light conversion efficiency is further improved. Meanwhile, a molecular chain of the single-component organic silica gel has good flexibility and rotation easiness, shows excellent high and low temperature resistance, can bear long-term severe environmental impact, and particularly has excellent yellowing resistance in a high-temperature environment, so that the long-term service life is ensured.

Description

Technical Field

[0001] The present invention relates to the technical field of solar cell assembly, and particularly to a preparation method of silicone rubber for HJT (Hetero Junction Technology) or TOPCON (Tunnel Oxide Passivating Contacts) process. Background Art

[0002] In the encapsulation process of crystalline cells, the traditional high-temperature encapsulation method generally uses soldering technology. Soldering is a method of heating a low-melting-point metal solder to a molten state and then infiltrating and filling the gaps at the joints of metal parts to achieve welding. However, the soldering process has extremely high requirements for the quality of welding points, and it is necessary to ensure that the surface of the solder joints is smooth and avoid defects such as excessive solder, false soldering, insufficient solder, and bridging, which results in a high defect rate in actual applications and affects the product quality and production efficiency.

[0003] In view of the limitations of the soldering process, many manufacturers have begun to explore the use of adhesives as an alternative. Currently, a variety of adhesives for crystalline cell encapsulation have emerged on the market, mainly including photocurable acrylate, photocurable epoxy resin, and thermosetting silicone rubber, etc.

[0004] The photocurable acrylate adhesive is composed of components such as acrylate oligomers, acrylic monomers, reactive diluents, and photoinitiators. Under the irradiation of ultraviolet light, these components can rapidly undergo a free radical polymerization reaction to achieve rapid crosslinking and curing. The photocurable acrylate adhesive has the advantages of fast curing speed and high production efficiency, and can complete the curing process within a few seconds. However, this adhesive also has some disadvantages, such as a large volume shrinkage rate during the curing process, resulting in gaps between the encapsulated parts, which in turn affects the encapsulation effect. In addition, the surface drying difference of the photocurable acrylate adhesive is also relatively large, which increases the difficulty of process control.

[0005] The photocurable epoxy resin adhesive is composed of components such as alicyclic epoxy resins, reactive diluents, cationic initiators, and photosensitizers. Under the irradiation of ultraviolet light, the photoexcited cationic initiator generates a protonic acid, which in turn initiates the ring-opening reaction of the epoxy group to achieve rapid crosslinking and curing. The photocurable epoxy resin adhesive has the advantage of high bonding strength, but the curing speed is relatively slow and it is easily affected by the yellowing problem, which to a certain extent limits its application range.

[0006] Moreover, the photocurable acrylate adhesive and the photocurable epoxy resin adhesive are generally two-component binders, and the convenience of storage and use is relatively poor. Summary of the Invention

[0007] In view of the problems existing in the prior art, the present invention provides a one-component organosilicone rubber, a preparation method thereof and an application thereof. Preferably, the present invention provides a one-component organosilicone rubber for the encapsulation process of crystalline batteries, a preparation method thereof and an application thereof.

[0008] To achieve the above object, the technical solution adopted by the present invention is as follows:

[0009] On the one hand, the present invention provides a one-component organosilicone rubber, based on the weight of the one-component organosilicone rubber, by mass, the composition includes:

[0010] 15-35 parts of vinyl silicone oil;

[0011] 20-45 parts of hydrogen-containing silicone oil;

[0012] 25-55 parts of vinyl MQ resin;

[0013] 0.05-5 parts of catalyst.

[0014] Preferably, based on the weight of the one-component organosilicone rubber, by mass, the composition includes:

[0015] 20-30 parts of vinyl silicone oil;

[0016] 25-40 parts of hydrogen-containing silicone oil;

[0017] 30-50 parts of vinyl MQ resin;

[0018] 0.1-2 parts of catalyst.

[0019] Preferably, the one-component organosilicone rubber of the present invention may further contain any one or more of a tackifier, an inhibitor, an antioxidant, a pigment, a filler, a lubricant, and a flame retardant.

[0020] Preferably, the one-component organosilicone rubber of the present invention contains a tackifier. Based on the weight of the one-component organosilicone rubber, by mass, the tackifier is 0.8-10 parts, more preferably 1-5 parts.

[0021] Preferably, the one-component organosilicone rubber of the present invention contains an inhibitor. Based on the weight of the one-component organosilicone rubber, by mass, the inhibitor is 0.05-5 parts, more preferably 0.1-2 parts.

[0022] Preferably, the one-component organosilicone rubber of the present invention contains a filler. Based on the weight of the one-component organosilicone rubber, by mass, the filler is 2-15 parts, more preferably 5-10 parts.

[0023] Preferably, the vinyl silicone oil includes end-vinyl silicone oil and / or side-vinyl silicone oil, or end-side double-vinyl silicone oil.

[0024] Among them, the terminal vinyl silicone oil can be vinyl mono-terminated silicone oil or vinyl di-terminated silicone oil.

[0025] Preferably, the viscosity of the vinyl silicone oil (under standard atmospheric pressure, 25 °C) is 200 - 7000 mPas, preferably 300 - 5000 mPas, more preferably 500 - 1000 mPas.

[0026] Preferably, the vinyl silicone oil is terminal vinyl silicone oil.

[0027] Preferably, the mass content of vinyl in the vinyl silicone oil is 0.1% - 1.2%, preferably 0.1% - 0.8%, more preferably 0.1% - 0.5%.

[0028] Preferably, the viscosity of the hydrogen-containing silicone oil (under standard atmospheric pressure, 25 °C) is 5 - 300 mPas, preferably 8 - 200 mPas, more preferably 10 - 100 mPas.

[0029] Preferably, the hydrogen content (weight content) of the hydrogen-containing silicone oil is 0.1% - 1.5%, preferably 0.1% - 1.5%, more preferably 0.1% - 1.5%.

[0030] Preferably, the hydrogen-containing silicone oil can be a silicone oil containing terminal hydrogen and / or side hydrogen.

[0031] Among them, the silicone oil containing terminal hydrogen refers to the silicone oil with a silicon-hydrogen bond introduced at the end of the chain (also known as terminal hydrogen-containing silicone oil, end hydrogen silicone oil); the silicone oil containing side hydrogen is the silicone oil with a silicon-hydrogen bond introduced into the side chain of the ester molecule (also known as side hydrogen-containing silicone oil, side-chain hydrogen-containing silicone oil, side-terminal hydrogen-containing silicone oil, side hydrogen silicone oil).

[0032] More preferably, the mass ratio of the terminal hydrogen-containing silicone oil to the side hydrogen-containing silicone oil is (10 - 50) : (2 - 15), preferably (15 - 40) : (3 - 12), more preferably (20 - 30) : (5 - 10).

[0033] Preferably, the hydrogen-containing silicone oil can also be a silicone oil containing both terminal and side hydrogen, that is, a silicone oil with silicon-hydrogen bonds introduced at both the end of the chain and the side chain.

[0034] Preferably, the MQ ratio (i.e., M:Q value, molar ratio) of the vinyl MQ resin is 0.2 - 1, preferably 0.3 - 1, more preferably 0.5 - 1.

[0035] Preferably, the viscosity of the vinyl MQ resin (under standard atmospheric pressure, 25 °C) is 600 - 25000 mPas, preferably 800 - 28000 mPas, more preferably 1000 - 30000 mPas, especially 4000 - 1000 mPas.

[0036] Preferably, the vinyl content (by weight) in the vinyl MQ resin is preferably 0.1-2%, more preferably 0.3-1.7%, still more preferably 0.5-1.5%, still more preferably 0.6-1.2%, and still more preferably 0.8-1.0%. Preferably, the present invention may also contain VQM series products produced by Evonik to provide vinyl MQ resin. The VQM series products are mixtures containing vinyl QM resin and vinyl silicone oil, and can provide vinyl QM resin and vinyl silicone oil simultaneously.

[0037] Preferably, the mass content of vinyl QM resin in the VQM is 10-65%, preferably 15-55%, and more preferably 20-45%. Such as VQM985, VQM973, VQM909 produced by Evonik.

[0038] Preferably, the tackifier may be any one or more of rosin, hydrogenated rosin, polymerized rosin, maleic rosin, glycerol ester of rosin, hydrogenated glycerol ester of rosin, pentaerythritol ester of rosin, hydrogenated pentaerythritol ester of rosin, rosin-modified phenolic resin, terpene resin, β-terpene resin, terpene-phenol resin, terpene-styrene resin, terpene-phenolic resin, C5 petroleum resin, C9 petroleum resin, dicyclopentadiene petroleum resin, C5 / C9 copolymerized petroleum resin, piperylene petroleum resin, hydrogenated petroleum resin, styrene-indene resin, alkylphenolic resin, tall oil-modified phenolic resin, cashew oil-modified phenolic resin, poly-a-methylstyrene resin, polyketone resin, polyaldehyde resin, xylene formaldehyde resin, more preferably one of KH-560, KH-570, KH-171, and still more preferably KH-171.

[0039] Preferably, the catalyst is a compound capable of initiating or accelerating the curing of silicone polymers (such as through cross-linking reactions). Preferably, it may be any one or more of platinum-based catalysts, tin-based catalysts, peroxide catalysts, such as chloroplatinic acid, divinyltetramethyldisiloxane platinum complex, tin octoate, dibutyltin dilaurate, benzoyl peroxide, and diisopropyl peroxide. Especially preferably, it is a platinum-based catalyst, such as the Karstedt catalyst produced by Heraeus.

[0040] Preferably, the inhibitor refers to a substance that can reduce or lose the catalytic activity of the catalyst under the non-curing conditions of the one-component organosilicone rubber and restore the catalytic activity of the catalyst under the curing conditions. For example: 1) non-metals with unshared electron pairs and their compounds, such as N, P, and S organic compounds; 2) metal ion compounds such as Sn, Pb, Hg, Bi, and As; 3) unsaturated compounds; more preferably, unsaturated compounds, especially alkynyl-containing compounds or vinyl-containing (especially containing at least two vinyl groups) compounds. For example, benzotriazole, alkynyl-containing polyvinyl ether, isocyanate, fumarate, maleate, β-alkynol, etc., such as 1-ethynylcyclohexanol.

[0041] Preferably, the filler can be a composition selected from any one or several of kaolin, diatomaceous earth, talcum powder, graphite, carbon black, mica, quartz, limestone, calcite, wollastonite, white carbon black, silica, hollow microspheres, and fumed silica. More preferably, it is fumed silica or white carbon black, which is used to adjust the viscosity and thixotropy.

[0042] More preferably, the fumed silica is selected from at least one of Evonik R202, Evonik R208, Evonik R805, Evonik R812S, and Evonik R8200.

[0043] Preferably, the fumed silica is selected from Evonik R202.

[0044] On the other hand, the present invention provides a method for preparing the aforementioned one-component organosilicone rubber, which includes the following steps:

[0045] Mix vinyl silicone oil, hydrogen-containing silicone oil, and vinyl MQ resin to obtain a first mixture;

[0046] Add a catalyst to the first mixture and mix to obtain a second mixture;

[0047] Defoam the second mixture, dispense it into a cartridge and seal it to obtain the one-component organosilicone rubber.

[0048] Preferably, an inhibitor is further added to the one-component organosilicone rubber. The inhibitor can be added to the first mixture or the second mixture. Preferably, the inhibitor is added to the first mixture together with the catalyst.

[0049] Preferably, in the first mixture or the second mixture, a tackifier, an antioxidant, a pigment, a filler, a lubricant, a flame retardant, or any one or more of them can be added. For example, a tackifier is added to the first mixture and a filler is added to the second mixture. Preferably, the tackifier is added together with the vinyl silicone oil, and the filler is added together with the catalyst.

[0050] Preferably, the temperature for mixing vinyl silicone oil, hydrogen-containing silicone oil, vinyl MQ resin, and tackifier is 15 - 50°C, preferably 20 - 45°C, more preferably 25 - 40°C.

[0051] Preferably, the mixing time of vinyl silicone oil, hydrogen-containing silicone oil, vinyl MQ resin, and tackifier is 10 - 60 min, preferably 20 - 50 min, more preferably 30 - 40 min.

[0052] Preferably, the temperature for mixing the first mixture with inhibitor, filler, and catalyst is 15 - 50°C, preferably 20 - 45°C, more preferably 25 - 40°C.

[0053] Preferably, the mixing time of the first mixture with inhibitor, filler, and catalyst is 10 - 60 min, preferably 20 - 50 min, more preferably 30 - 40 min.

[0054] Preferably, the rotation speed for defoaming the second mixture is 200 - 1500 r / min, preferably 300 - 1200 r / min, more preferably 500 - 1000 r / min.

[0055] Preferably, the defoaming time of the second mixture is 1 - 10 min, preferably 2 - 8 min, more preferably 2 - 6 min.

[0056] Preferably, the prepared one-component silicone rubber is stored frozen at (-30) - 0°C, preferably (-25) - 0°C, more preferably (-20) - 0°C.

[0057] On the other hand, the present invention provides the application of the one-component silicone rubber in HIT solar cells or TOPCon cells.

[0058] In the specification of this application, vinyl MQ resin is a special silicone resin composed of monofunctional siloxane linkages (M units) and tetrafunctional siloxane condensation linkages (Q units). The structural formula of this application is (CH 3 ) 2 (CH 2 =CH)SiO 1 / 2 a [(CH 3 ) 3 SiO 1 / 2 b [SiO 4 / 2 c , where [(CH 3 ) 2 (CH 2 =CH)SiO 1 / 2 a ​​​​[(CH 3 ) 3 SiO 1 / 2 b is of M structure, [SiO 4 / 2 c is of Q structure, a, b, and c are numbers ≥ 0, and the M:Q value is (a + b) / c.

[0059] In the above content of the present invention, without special statement, the viscosity is the dynamic viscosity.

[0060] Compared with the prior art, the present application has the following beneficial effects:

[0061] The present application provides a one-component silicone rubber, which meets the bonding and fixing requirements of low-temperature solder tapes and meets the lamination requirements. Compared with the traditional sealing method, the one-component silicone rubber of the present invention:

[0062] 1) In terms of storage stability and curing speed, the one-component silicone rubber of the present application, through a unique catalyst-inhibitor system, not only ensures good storage stability, with a viscosity increase of < 50% after 8 hours at 25°C, but also can be quickly cured at high temperature, forming a firm bond within 150°C / 10 min. The cured silicone rubber has a high light transmittance, further improving the light conversion efficiency.

[0063] 2) At the same time, the molecular chain of the one-component silicone rubber of the present application has good flexibility and easy rotatability, showing excellent high and low temperature resistance, and can withstand long-term severe environmental impacts under thermal shock (-40 - 125°C, 200 times, no fracture). Especially in a high temperature environment, its yellowing resistance is excellent, with a light transmittance > 90% at 150°C / 48 h, ensuring a long service life.

[0064] In summary, the one-component silicone rubber of the present application shows significant advantages in bonding and fixing, light transmittance, high temperature resistance, high and low temperature resistance, as well as storage stability and curing speed, providing technical support for the application fields of HIT solar cells or TOPCON cells. Specific Embodiments

[0065] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of them. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention. Additionally, it is worth noting that the raw materials involved in the present invention are all ordinary commercially available products without special description.

[0066] Example 1

[0067] ​​This embodiment provides a preparation method of a one-component organosilica gel, and the steps include:

[0068] (1) Provide the raw material composition of the one-component organosilica gel, including:

[0069] 30 wt% of vinyl silicone oil, with a viscosity of 1000 cps at 25 °C and a vinyl content of 0.32%;

[0070] 23 wt% of hydrogen-containing silicone oil, with a viscosity of 70 cps at 25 °C, including side hydrogen and terminal hydrogen, and its hydrogen content is 0.77%;

[0071] 40 wt% of vinyl MQ resin, with a viscosity of 1000 mPa·s and a vinyl content of 0.621%;

[0072] 1.5 wt% of tackifier, KH-560 produced by Hangzhou Jessica Company;

[0073] 0.5 wt% of catalyst, Karstedt catalyst produced by Heraeus Company, with a platinum content of 5000 ppm;

[0074] 0.5 wt% of inhibitor, TMDO produced by Beijing Forsman Company;

[0075] 4.5 wt% of fumed silica.

[0076] (2) At 20 - 30 °C, weigh the formulated amounts of vinyl silicone oil, hydrogen-containing silicone oil, vinyl MQ resin and tackifier, and add them to the stirring kettle in sequence, and stir well for 0.5 hours to obtain a first mixture to ensure uniform mixing of the raw materials.

[0077] (3) Add the formulated amounts of inhibitor, fumed silica and catalyst to the first mixture in sequence, add them to the stirring kettle in sequence, and stir well again for 0.5 hours to complete the preparation of the reaction system and obtain a second mixture.

[0078] (4) Perform degassing treatment on the prepared second mixture, and dispense it into rubber tubes to obtain the one-component organosilica gel described in this embodiment, and store it in an environment of -20 °C for subsequent use.

[0079] Example 2

[0080] This embodiment provides a preparation method of a one-component organosilica gel, and the steps include:

[0081] (1) Provide the raw material composition of the one-component organosilica gel, including:

[0082] 32.5 wt% of vinyl silicone oil, with a viscosity of 500 cps at 25 °C and a vinyl content of 0.44%;

[0083] 27.5 wt% of hydrogen-containing silicone oil with a viscosity of 40 cps at 25°C, including side hydrogen and end hydrogen, and its hydrogen content is 0.44%;

[0084] 33 wt% of vinyl MQ resin with a viscosity of 30000 mPa·s and a vinyl content of 0.918%;

[0085] 1.5 wt% of tackifier, KH-560 produced by Hangzhou Jessica Company;

[0086] 0.5 wt% of catalyst, Karstedt catalyst produced by Heraeus Company with a platinum content of 5000 ppm;

[0087] 0.5 wt% of inhibitor, TMDO produced by Beijing Forsman Company;

[0088] 4.5 wt% of fumed silica.

[0089] (2) At room temperature (20 - 30°C), weigh the formulated amounts of vinyl silicone oil, hydrogen-containing silicone oil, vinyl MQ resin, and tackifier, and add them to the stirring kettle in sequence, and stir thoroughly for 0.5 hours to obtain the first mixture to ensure uniform mixing of the raw materials.

[0090] (3) Add the formulated amounts of inhibitor, fumed silica, and catalyst to the first mixture in sequence and add them to the stirring kettle, and stir thoroughly again for 0.5 hours to complete the preparation of the reaction system and obtain the second mixture.

[0091] (4) Carry out degassing treatment on the prepared second mixture, sub-pack it into rubber tubes to obtain the one-component silicone rubber described in this example, and store it in an environment of -20°C for subsequent use.

[0092] Example 3

[0093] This example provides a preparation method of a one-component silicone rubber, and the steps include:

[0094] (1) Provide the raw material composition of the one-component silicone rubber, including:

[0095] 20 wt% of vinyl silicone oil with a viscosity of 500 cps at 25°C and a vinyl content of 0.44%;

[0096] 38 wt% of hydrogen-containing silicone oil with a viscosity of 40 cps at 25°C, including side hydrogen and end hydrogen, and its hydrogen content is 0.44%;

[0097] 35 wt% of vinyl MQ resin with a viscosity of 4000 mPa·s and a vinyl content of 1.215%;

[0098] 1.5 wt% of tackifier, KH-560 produced by Hangzhou Jessica Company;

[0099] 0.5 wt% of catalyst, Karstedt catalyst produced by Heraeus Company, with a platinum content of 5000 ppm;

[0100] 0.5 wt% of inhibitor, TMDO produced by Beijing Forsman Company;

[0101] 4.5 wt% of silica white.

[0102] (2) At room temperature (20 - 30 °C), weigh the formulated amounts of vinyl silicone oil, hydrogen-containing silicone oil, vinyl MQ resin, and tackifier, and add them to the stirring kettle in sequence, and stir well for 0.5 hours to obtain the first mixture to ensure uniform mixing of the raw materials.

[0103] (3) Add the formulated amounts of inhibitor, silica white, and catalyst to the first mixture in sequence, add them to the stirring kettle in sequence, and stir well again for 0.5 hours to complete the preparation of the reaction system and obtain the second mixture.

[0104] (4) Perform degassing treatment on the prepared second mixture, dispense it into rubber tubes to obtain the one-component silicone rubber described in this example, and store it in an environment of -20 °C for subsequent use.

[0105] Comparative Example 1

[0106] This comparative example provides a preparation method for one-component silicone rubber, and the steps include:

[0107] (1) Provide the raw material composition of the one-component silicone rubber, including:

[0108] 70 wt% of vinyl silicone oil, with a viscosity of 1000 cps at 25 °C and a vinyl content of 0.32%;

[0109] 23 wt% of hydrogen-containing silicone oil, with a viscosity of 70 cps at 25 °C, including side hydrogen-containing and end hydrogen-containing, and its hydrogen content is 0.77%;

[0110] 1.5 wt% of tackifier, KH-560 produced by Hangzhou Jessica Company;

[0111] 0.5 wt% of catalyst, Karstedt catalyst produced by Heraeus Company, with a platinum content of 5000 ppm;

[0112] 0.5 wt% of inhibitor, TMDO produced by Beijing Forsman Company;

[0113] 4.5 wt% of silica white.

[0114] (2) At room temperature (20 - 30 °C), weigh the formulated amounts of vinyl silicone oil, hydrogen-containing silicone oil, and tackifier, and add them to the stirring kettle in sequence, and stir well for 0.5 hours to obtain the first mixture, ensuring uniform mixing of the raw materials.

[0115] (3) Add the formulated amounts of inhibitor, fumed silica, and catalyst to the first mixture in sequence, add them to the stirring kettle, and stir well again for 0.5 hours to complete the preparation of the reaction system and obtain the second mixture.

[0116] (4) Debubble the prepared second mixture, dispense it into rubber tubes to obtain the one-component silicone rubber described in this comparative example, and store it in an environment of -20 °C for subsequent use.

[0117] Comparative Example 2

[0118] This comparative example provides a preparation method for one-component silicone rubber, and the steps include:

[0119] (1) Provide the raw material composition of the one-component silicone rubber, including:

[0120] 56 wt% of vinyl silicone oil, with a viscosity of 500 cps at 25 °C and a vinyl content of 0.44%;

[0121] 7 wt% of hydrogen-containing silicone oil, with a viscosity of 40 cps at 25 °C, including side hydrogen and terminal hydrogen, and its hydrogen content is 0.44%;

[0122] 30 wt% of vinyl MQ resin, DY-VMQ101 produced by Shandong Dayi Chemical Co., Ltd., white powder, soluble in vinyl silicone oil, with a vinyl content of 1.62%;

[0123] 1.5 wt% of tackifier, KH-560 produced by Hangzhou Jessica Co., Ltd.;

[0124] 0.5 wt% of catalyst, Karstedt catalyst produced by Heraeus, with a platinum content of 5000 ppm;

[0125] 0.5 wt% of inhibitor, TMDO produced by Beijing Fosman Co., Ltd.;

[0126] 4.5 wt% of fumed silica.

[0127] (2) At room temperature (20 - 30 °C), weigh the formulated amounts of vinyl silicone oil, hydrogen-containing silicone oil, vinyl MQ resin, and tackifier, and stir well for 0.5 hours to obtain the first mixture, ensuring uniform mixing of the raw materials.

[0128] (3) Sequentially add the formulated amounts of inhibitor, silica white, and catalyst to the first mixture, and add them to the stirring kettle in sequence. Stir well again for 0.5 hours to complete the preparation of the reaction system and obtain the second mixture.

[0129] (4) Debubble the prepared second mixture, and divide and fill it into rubber tubes to obtain the one-component silicone rubber described in this comparative example. Then store it in an environment of -20°C for subsequent use.

[0130] Comparative Example 3

[0131] This comparative example provides a preparation method for one-component silicone rubber. The steps include:

[0132] (1) Provide the raw material composition of the one-component silicone rubber, including:

[0133] 30 wt% vinyl silicone oil, with a viscosity of 1000 cps at 25°C and a vinyl content of 0.32%;

[0134] 23 wt% hydrogen-containing silicone oil, with a viscosity of 65 cps at 25°C, only including side hydrogen, and its hydrogen content is 0.74%;

[0135] 40 wt% vinyl MQ resin, with a viscosity of 10000 mPa·s and a vinyl content of 0.621%;

[0136] 1.5 wt% tackifier, KH-560 produced by Hangzhou Jessica Company;

[0137] 0.5 wt% catalyst, Karstedt catalyst produced by Heraeus Company, with a platinum content of 5000 ppm;

[0138] 0.5 wt% inhibitor, TMDO produced by Beijing Forsman Company;

[0139] 4.5 wt% silica white.

[0140] (2) At room temperature (20 - 30°C), weigh the formulated amounts of vinyl silicone oil, hydrogen-containing silicone oil, vinyl MQ resin, and tackifier, and stir well for 0.5 hours to obtain the first mixture to ensure uniform mixing of the raw materials.

[0141] (3) Sequentially add the formulated amounts of inhibitor, silica white, and catalyst to the first mixture, and add them to the stirring kettle in sequence. Stir well again for 0.5 hours to complete the preparation of the reaction system and obtain the second mixture.

[0142] (4) Debubble the prepared second mixture, and divide and fill it into rubber tubes to obtain the one-component silicone rubber described in this comparative example. Then store it in an environment of -20°C for subsequent use.

[0143] Comparative Example 4

[0144] This comparative example provides a method for preparing a one - component silicone rubber, and the steps include:

[0145] (1) Provide the raw material composition of the one - component silicone rubber, including:

[0146] 30 wt% vinyl silicone oil, with a viscosity of 2000 cps at 25 °C and a vinyl content of 0.46%;

[0147] 23 wt% hydrogen - containing silicone oil, with a viscosity of 70 cps at 25 °C, including side - hydrogen - containing and end - hydrogen - containing, and its hydrogen content is 0.77%;

[0148] 30 wt% vinyl MQ resin, with a viscosity of 1000 mPa·s and a vinyl content of 0.621%;

[0149] 1.5 wt% tackifier, KH - 560 produced by Hangzhou Jessica Company;

[0150] 0.5 wt% catalyst, Karstedt catalyst produced by Heraeus Company, with a platinum content of 5000 ppm;

[0151] 0.5 wt% inhibitor, TMDO produced by Beijing Forsman Company;

[0152] 4.5 wt% fumed silica.

[0153] (2) At room temperature (20 - 30 °C), weigh the formulated amounts of vinyl silicone oil, hydrogen - containing silicone oil, vinyl MQ resin and tackifier, and stir well for 0.5 hours to obtain a first mixture to ensure uniform mixing of the raw materials.

[0154] (3) Sequentially add the formulated amounts of inhibitor, fumed silica and catalyst to the first mixture, add them to the stirring kettle in sequence, and stir well again for 0.5 hours to complete the preparation of the reaction system and obtain a second mixture.

[0155] (4) Perform degassing treatment on the prepared second mixture, dispense it into rubber tubes to obtain the one - component silicone rubber described in this comparative example, and store it in an environment of - 20 °C for subsequent use.

[0156] List the raw material compositions of Examples 1 - 3 and Comparative Examples 1 - 4 in Table 1.

[0157] Table 1. Raw material compositions of Examples 1 - 3 and Comparative Examples 1 - 4

[0158]

[0159] Performance Test

[0160] Test the viscosity stability, light transmittance, shear strength, and peel strength of the examples and comparative examples of this application. The test methods are as follows (please provide the test methods):

[0161] Viscosity stability: Brookfield DVN CP52 rotor @ 5 rpm, 25 °C, viscosities at 0 h and 8 h

[0162] Curing process (including temperature and time): Use a non-rotating rheometer to test the vulcanization curve of the glue under the conditions of 150 °C @ 10 min, and record the data of TC10 / s, TC50 / s, and TC90 / s (TC is the time required for the specimen to reach a certain degree of vulcanization. For example, TC10 / s is the time for the specimen to reach 10% vulcanization degree, in s).

[0163] Light transmittance: Measure the transmittance at a specific wavelength (700 nm) through a UV spectrophotometer.

[0164] Shear strength: Lap aluminum sheets with an area of 25 mm * 15 mm, and test the shear strength after curing at 150 °C / 10 mins.

[0165] Peel strength: Use a tinned wire with a diameter of 150 um to lap with the battery chip, and test the peel strength after curing at 150 °C / 10 mins.

[0166] List the characterization properties of the one-component silicone rubbers of Examples 1-3 and Comparative Examples 1-4 in Table 2.

[0167] Table 2, Properties of the silicone rubbers of Examples 1-3 and Comparative Examples 1-4

[0168]

[0169] The above test results show that the one-component silicone rubbers provided in Examples 1-3 of this application simultaneously meet the requirements of light transmittance > 90%, shear strength > 1.5 Mpa, and peel strength > 0.2 N, and can be used for the bonding between the solder tape and the battery chip during the encapsulation process of crystal batteries.

[0170] In contrast, if the combination of vinyl MQ resin and vinyl silicone oil is not used, the Al-Al shear strength is greatly affected. At the same time, if the hydrogen-containing silicone oil is absent or the content is too low, it will also significantly reduce the Al-Al shear strength. For example, in Comparative Example 2, the Al-Al shear strength is no longer sufficient for the welding of battery chips, indicating that vinyl MQ resin, hydrogen-containing silicone oil, and vinyl silicone oil can play a synergistic effect within the scope of the present invention.

[0171] The viscosity of vinyl silicone oil also affects the Al-Al shear strength. The viscosity of vinyl silicone oil should not be too high, and it is preferably between 500 and 1000 mPa·s.

[0172] It is not advisable to use solid vinyl MQ resin. It is better to choose a liquid product with a certain viscosity. The viscosity can be preferably 600 - 25000 mPa·s, especially 4000 - 10000 mPa·s.

[0173] When both terminal and side hydrogen silicone oils are contained, the Al-Al shear strength is better. If only side hydrogen silicone oil is used, the decrease in Al-Al shear strength is also relatively obvious, and this influence is beyond expectation.

[0174] The present invention is a one-component adhesive with very good stability. Compared with two-component silicone rubber, the process of the one-component silicone rubber in this embodiment is simpler, the processing efficiency is higher, the mixing / defoaming process before using the two components is omitted, and the production and transfer of the production line are more efficient.

[0175] Finally, it should be noted that the above content is only used to illustrate the technical solution of the present invention, rather than limiting the protection scope of the present invention. Any simple modification or equivalent replacement of the technical solution of the present invention by those of ordinary skill in the art does not depart from the essence and scope of the technical solution of the present invention.

Claims

1. A one-component organic silica gel, characterized in that: Based on the weight of the single-component organic silica gel, the composition includes: 15-35 parts of vinyl silicone oil; 20-45 parts of hydrogen silicone oil; 25-55 parts of vinyl MQ resin; Catalyst 0.05-5 parts.

2. The one-component organic silica gel according to claim 1, characterized in that: Based on the weight of the single-component organic silica gel, the composition by mass includes: 20-30 parts of vinyl silicone oil; 25-40 parts of hydrogen silicone oil; 30-50 parts of vinyl MQ resin; Catalyst 0.1-2 parts.

3. The one-component organic silica gel according to claim 1, characterized in that: The vinyl silicone oil has a dynamic viscosity of 200-7000 mpas; and / or The hydrogen-containing silicone oil has a dynamic viscosity of 5-300 mpas and a hydrogen content of 0.1%-1.5%.

4. The one-component organic silica gel according to claim 1, characterized in that: The hydrogen-containing silicone oil comprises at least one of terminal hydrogen silicone oil and side hydrogen silicone oil; and / or The mass ratio of the terminal hydrogen-containing silicone oil to the end side hydrogen-containing silicone oil is (10-50):(2-15).

5. The one-component organic silica gel according to claim 1, characterized in that: The vinyl silicone oil includes terminal vinyl silicone oil and / or side vinyl silicone oil, or terminal and side divinyl silicone oil; the vinyl silicone oil has a vinyl mass content of 0.1%-1.2%.

6. The one-component organic silica gel according to claim 1, characterized in that: The vinyl MQ resin has a dynamic viscosity of 600-25000 mpas, an MQ ratio of 0.2-1, and a vinyl content of 0.1-2%.

7. The one-component organic silica gel according to claim 1, characterized in that: It also contains any one or more of a tackifier, an inhibitor, an antioxidant, a pigment, a filler, a lubricant, and a flame retardant; based on the weight of the single-component organic silica gel, the tackifier is 0.8-10 parts, the inhibitor is 0.05-5 parts, and the filler is 2-15 parts.

8. A method for preparing the one-component organic silica gel according to claim 1, characterized in that: The steps include: Mixing vinyl silicone oil, hydrogen-containing silicone oil, and vinyl MQ resin to obtain a first mixture; adding a catalyst to the first mixture and mixing to obtain a second mixture; The second mixture is degassed, packed into rubber cartridges and sealed to obtain the one-component organic silica gel.

9. The preparation method according to claim 8, characterized in that: The temperature of the mixture of vinyl silicone oil, hydrogen silicone oil and vinyl MQ resin is 15-50°C; and / or The mixing time of vinyl silicone oil, hydrogen silicone oil and vinyl MQ resin is 10-60 minutes; and / or The temperature of the first mixture and the catalyst is 15-50°C; and / or The mixing time of the first mixture and the catalyst is 10-60 minutes; The degassing time of the second mixture is 1-10 min.

10. Use of the one-component organic silica gel according to any one of claims 1 to 7, characterized in that: The single-component organic silicon is applied to HIT solar cells or TOPCON cells.

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