Two-component sealant as well as preparation method and application thereof

Abstract

The invention relates to a two-component sealant as well as a preparation method and application thereof. The double-component sealant comprises a component A and a component B, the component A comprises amino resin; and the component B comprises an isocyanate curing agent X and an isocyanate curing agent Y. The two-component sealant has excellent water vapor barrier property, and can provide good waterproof protection for internal materials when being applied to the photovoltaic module, so that the service life of the photovoltaic module is effectively prolonged; meanwhile, the double-component sealant also has high strength and good thermal stability.

Description

Technical Field

[0001] The present invention relates to the technical field of sealants, and in particular to a two-component sealant and a preparation method and application thereof. Background Art

[0002] As a type of sealant with excellent performance, silicone sealant has good resilience, high heat resistance that can be used at 200°C, and excellent resistance to UV aging. It is widely used in sealing in construction, automobiles, photovoltaics, electronics and other scenarios. Photovoltaics, as one of the main forces of new clean power generation energy, has developed rapidly in recent years. Photovoltaic modules are one of the places where silicone sealants are widely used.

[0003] However, with the iteration and update of material technology, many application scenarios have increasingly highlighted the problem of materials being afraid of water vapor. For example, in the photovoltaic field, as power generation cells are transformed from perc type to topcon, HJT, perovskite and other technologies, the sensitivity of battery materials to water vapor has increased. However, existing silicone sealants have poor water vapor barrier properties, and their water vapor transmission rate is generally between 80-100g / (m 2 ·day). During the long-term operation of photovoltaic modules and electronic devices, external water vapor continuously penetrates through the sealant and penetrates into the components, causing the components to be damaged and fail, shortening their lifespan. Therefore, existing silicone sealants cannot provide good protection for internal power generation batteries, limiting their scope of use. In some electronic potting fields, the same technical problems are also faced. Water vapor erosion will directly affect the service life of photovoltaic modules, electronic devices, etc., making its impact on the industry immeasurable.

[0004] Therefore, it is of great significance to design and develop a sealant with excellent water vapor barrier properties and good thermal stability. Summary of the invention

[0005] In order to solve the above technical problems, the present invention provides a two-component sealant and a preparation method and application thereof. The two-component sealant has excellent water vapor barrier properties. When used in photovoltaic modules, it can provide good water-proof protection for internal materials, thereby effectively extending the service life of photovoltaic modules; at the same time, the two-component sealant also has high strength and good thermal stability.

[0006] To achieve this object, the present invention adopts the following technical solutions:

[0007] In a first aspect, the present invention provides a two-component sealant, comprising component A and component B; component A comprises an amino resin; and component B comprises an isocyanate curing agent X and an isocyanate curing agent Y.

[0008] The present invention forms component A using amino resin as a raw material, and forms component B using isocyanate curing agent X and isocyanate curing agent Y as raw materials, so that the obtained two-component sealant has excellent water vapor barrier and thermal stability. At the same time, the two-component sealant of the present invention has a molecular structure mainly composed of -NHCONH-, high strength, good resilience, high thermal stability (heat-resistant up to 200°C), and excellent water resistance and UV resistance, which makes it have obvious advantages in thermal application scenarios with high requirements for water vapor barrier, such as encapsulating photovoltaic modules and motor sealing.

[0009] Preferably, the amino resin comprises polyaspartic acid ester.

[0010] Preferably, the polyaspartic acid ester has a structure shown in formula (I):

[0011]

[0012] Wherein, R1, R2, R3, and R4 are each independently selected from one or more of substituted or unsubstituted C1-C18 alkyl, substituted or unsubstituted C6-C18 aryl, and substituted or unsubstituted C2-C16 hydrocarbon groups; the substituents include H, halogen, or C1-C5 alkyl;

[0013] X is selected from Any one of the groups, preferably

[0014]

[0015] In the present invention, C1-C18 may be, for example, C1, C3, C5, C8, C10, C12, C15 or C18, C6-C18 may be, for example, C6, C10, C12, C13, C14, C15, C16, C17 or C18, C2-C16 may be, for example, C2, C4, C6, C8, C10, C12, C14 or C16, and C1-C5 may be, for example, C1, C2, C3, C4 or C5. Halogen may be, for example, fluorine, chlorine or bromine.

[0016] In the present invention, when X is When the amino resin is added, the steric hindrance of the structure of the specific amino resin is large, the reactivity of -NH is weakened, and the reaction rate of -NH and isocyanate is slowed down, so that the room temperature gel time of the obtained two-component sealant can be regulated, and the actual production needs can be better met. At the same time, it also improves the water vapor barrier property of the obtained two-component sealant to a certain extent.

[0017] Preferably, the mass ratio of the isocyanate curing agent X to the isocyanate curing agent Y is 1:(0.37-1), and (0.37-1) can be, for example, 0.37, 0.375, 0.38, 0.4, 0.46, 0.5, 0.6, 0.7, 0.8, 0.9 or 1, as well as specific point values ​​between the above point values. Due to space limitations and for the sake of simplicity, the present invention no longer exhaustively lists the specific point values ​​included in the range, and is further preferably 1:(0.46-0.8).

[0018] In the present invention, isocyanate curing agent X and isocyanate curing agent Y are compounded, and the curing crosslinking degree of the colloid is first adjusted to obtain good mechanical properties such as elongation and tensile modulus. At the same time, the introduction of a monofunctional secondary amine with a long carbon chain structure is helpful to the water vapor barrier of the colloid. Further, when the mass ratio of the two is 1: (0.46-0.8), the technical effect is better. When the mass ratio of the two is higher than 1: 0.46, the proportion of isocyanate curing agent Y is too low, the crosslinking density of the colloid is too high, the tensile modulus is large, the resilience is poor, and the water vapor barrier is slightly poor; when the mass ratio of the two is lower than 1: 0.8, the proportion of isocyanate curing agent Y is too high, the crosslinking density of the colloid is too low, and the heat resistance is insufficient.

[0019] Preferably, the isocyanate curing agent X comprises HDI trimer and / or HDI biuret.

[0020] Preferably, the isocyanate curing agent Y is an isocyanate adduct of a monofunctional amine.

[0021] Preferably, the isocyanate adduct of the monofunctional amine is obtained by reacting isocyanate with a monofunctional amine.

[0022] Preferably, the molar ratio of isocyanate to monofunctional amine in the reaction is (1.01-1.25):1, (1.01-1.25) can be, for example, 1.01, 1.03, 1.1, 1.12, 1.15, 1.18, 1.2, 1.23 or 1.25, as well as specific point values ​​between the above point values. Due to space limitations and for the sake of simplicity, the present invention no longer exhaustively lists the specific point values ​​included in the range.

[0023] Preferably, the temperature of the external heat source of the reaction is 45-55°C, for example, it can be 45°C, 48°C, 50°C, 52°C or 55°C, as well as specific point values ​​between the above point values. Due to space limitations and for the sake of simplicity, the present invention no longer exhaustively lists the specific point values ​​included in the range.

[0024] Preferably, the isocyanate comprises an aliphatic difunctional isocyanate.

[0025] Preferably, the aliphatic difunctional isocyanate includes any one or a combination of at least two of hexamethylene diisocyanate (HDI), isophorone diisocyanate (IPDI), dicyclohexylmethane-4,4'-diisocyanate (HMDI), 1,4-cyclohexane diisocyanate (CHDI), hydrogenated xylylene diisocyanate (HXDI), methylcyclohexane diisocyanate (HTDI), trimethylhexamethylene diisocyanate (TMDI) or 1,5-pentamethylene diisocyanate (PDI).

[0026] Preferably, the monofunctional amine comprises a monofunctional secondary amine.

[0027] Preferably, the monofunctional secondary amine includes any one of di-n-butylamine, di-n-hexylamine, dioctylamine or dicyclohexylamine, or a combination of at least two thereof.

[0028] Preferably, the monofunctional amine in the reaction is dried in advance.

[0029] Preferably, the drying treatment comprises molecular sieve drying and / or vacuum drying.

[0030] Preferably, the molecular sieve drying includes soaking the molecular sieve for 20-30 hours, for example, it can be 20 hours, 21 hours, 22 hours, 23 hours, 24 hours, 25 hours, 26 hours, 7 hours, 28 hours, 29 hours or 30 hours, as well as specific point values ​​between the above point values. Due to space limitations and for the sake of simplicity, the present invention no longer exhaustively lists the specific point values ​​included in the range.

[0031] Preferably, the vacuum drying comprises vacuum drying at 110-130°C (for example, it may be 112°C, 114°C, 116°C, 118°C, 120°C, 122°C, 124°C, 126°C or 128°C, etc.) for 1-3h (for example, it may be 1.2h, 1.4h, 1.6h, 1.8h, 2h, 2.2h, 2.4h, 2.6h or 2.8h, etc.).

[0032] Preferably, the reaction is carried out under a protective gas atmosphere.

[0033] Preferably, the protective gas includes any one of nitrogen, argon or helium, or a combination of at least two of them.

[0034] Preferably, the reaction is stopped when the mass fraction of isocyanate in the reaction system is determined to be 10.6-14.4% (for example, 10.6%, 11%, 11.5%, 12%, 12.5%, 13%, 13.5%, 14% or 14.4%, etc.).

[0035] Preferably, the specific preparation method of the isocyanate curing agent Y in the present invention comprises the following steps:

[0036] In a protective gas atmosphere, an external heat source is 45-55° C., and a dried monofunctional amine is added to the isocyanate to obtain the isocyanate curing agent Y. The molar ratio of the isocyanate to the monofunctional amine is (1.01-1.25):1.

[0037] Preferably, the component A further comprises a plasticizer.

[0038] Preferably, the plasticizer includes any one of liquid carbon nine petroleum resin, liquid hydrogenated carbon nine petroleum resin, cashew nut shell oil diluent or 2,6-diisopropylnaphthalene, or a combination of at least two thereof.

[0039] The selection of the specific plasticizer of the present invention is conducive to improving the water vapor barrier property of the obtained two-component sealant, and the plasticizers all have a dense molecular structure such as a long carbon chain, which is conducive to forming a barrier to block water vapor. At the same time, the specific plasticizer of the present invention can also improve the heat resistance and adhesion of the obtained two-component sealant.

[0040] Preferably, the component A further comprises any one of a dewatering agent, carbon black, a filler, a defoaming agent or an antioxidant, or a combination of at least two thereof.

[0041] Preferably, the water removal agent comprises 4A molecular sieve.

[0042] Preferably, the carbon black comprises specialty carbon black.

[0043] Preferably, the filler comprises a surface-modified or unmodified filler.

[0044] Preferably, the filler comprises any one or a combination of at least two of calcium carbonate, boehmite, aluminum hydroxide, aluminum oxide, magnesium hydroxide, kaolin, silica powder, mica powder or talc;

[0045] Preferably, the defoaming agent comprises a polysiloxane defoaming agent.

[0046] Preferably, the antioxidant includes any one of a hindered phenol antioxidant, an aromatic secondary amine antioxidant, a phosphite antioxidant or a thioether antioxidant, or a combination of at least two thereof.

[0047] Preferably, the hindered phenol antioxidant includes any one of antioxidant 1010, antioxidant 1098, antioxidant 2246, antioxidant 425 or antioxidant 330, or a combination of at least two thereof.

[0048] Preferably, the aromatic secondary amine antioxidant includes butylated hydroxyanisole (BHA) and / or N,N'-di-sec-butyl-p-phenylenediamine (BPA).

[0049] Preferably, the phosphite antioxidant includes any one of antioxidant 168, antioxidant 618 or antioxidant 9928, or a combination of at least two of them.

[0050] Preferably, the thioether antioxidant includes any one of distearate thiodipropionate (DSTDP), didodecyl thiodipropionate (DLTDP) or pentaerythritol tetrakis (3-laurylthiopropionate) or a combination of at least two thereof.

[0051] In the present invention, the special combination of specific antioxidants can improve the long-term thermal stability of the obtained two-component sealant.

[0052] Preferably, the component A comprises the following components in parts by weight:

[0053]

[0054]

[0055] In the present invention, the content of amino resin is 55-75 parts by weight, for example, it can be 55 parts by weight, 57 parts by weight, 60 parts by weight, 62 parts by weight, 65 parts by weight, 68 parts by weight, 70 parts by weight, 72 parts by weight or 75 parts by weight, as well as specific values ​​between the above points. Due to space limitations and for the sake of simplicity, the present invention no longer exhaustively lists the specific points included in the range.

[0056] The content of the dehydrating agent is 0-5 parts by weight, for example, it can be 0 parts by weight, 1 part by weight, 2 parts by weight, 3 parts by weight, 4 parts by weight or 5 parts by weight, as well as specific values ​​between the above points. Due to space limitations and for the sake of simplicity, the present invention no longer exhaustively lists the specific points included in the range.

[0057] The content of carbon black is 0-1.5 parts by weight, for example, it can be 0 parts by weight, 0.2 parts by weight, 0.5 parts by weight, 0.8 parts by weight, 1 part by weight, 1.2 parts by weight or 1.5 parts by weight, as well as specific points between the above points. Due to space limitations and for the sake of simplicity, the present invention no longer exhaustively lists the specific points included in the range.

[0058] The content of filler is 20-60 parts by weight, for example, it can be 20 parts by weight, 25 parts by weight, 30 parts by weight, 35 parts by weight, 40 parts by weight, 45 parts by weight, 50 parts by weight, 55 parts by weight or 60 parts by weight, as well as specific points between the above points. Due to space limitations and for the sake of simplicity, the present invention no longer exhaustively lists the specific points included in the range.

[0059] The content of the defoaming agent is 0-0.2 parts by weight, for example, it can be 0 parts by weight, 0.03 parts by weight, 0.05 parts by weight, 0.08 parts by weight, 0.1 parts by weight, 0.13 parts by weight, 0.15 parts by weight, 0.18 parts by weight or 0.2 parts by weight, as well as specific points between the above points. Due to space limitations and for the sake of simplicity, the present invention no longer exhaustively lists the specific points included in the range.

[0060] The content of antioxidant is 0-1 weight part, for example, it can be 0 weight part, 0.1 weight part, 0.2 weight part, 0.3 weight part, 0.4 weight part, 0.5 weight part, 0.6 weight part, 0.7 weight part, 0.8 weight part, 0.9 weight part or 1 weight part, as well as specific point values ​​between the above point values. Due to space limitations and for the sake of simplicity, the present invention no longer exhaustively lists the specific point values ​​included in the said range.

[0061] The content of plasticizer is 0-8 parts by weight, for example, it can be 0 parts by weight, 1 part by weight, 2 parts by weight, 3 parts by weight, 4 parts by weight, 5 parts by weight, 6 parts by weight, 7 parts by weight or 8 parts by weight, as well as specific points between the above points. Due to space limitations and for the sake of simplicity, the present invention no longer exhaustively lists the specific points included in the range.

[0062] Preferably, the component B further comprises a silane coupling agent.

[0063] Preferably, the coupling agent comprises a silane coupling agent.

[0064] Preferably, the silane coupling agent includes any one of 3-glycidyloxypropyltrimethoxysilane, 3-glycidyloxypropyltriethoxysilane, β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, β-(3,4-epoxycyclohexyl)ethyltriethoxysilane, 3-isocyanatepropyltrimethoxysilane or 3-isocyanatepropylethoxysilane, or a combination of at least two thereof.

[0065] Preferably, the component B comprises the following components in parts by weight:

[0066] Isocyanate curing agent X 25-40 parts by weight Isocyanate curing agent Y 15-25 parts by weight Coupling agent 0-5 parts by weight.

[0067] In the present invention, the content of isocyanate curing agent X is 25-40 parts by weight, for example, it can be 25 parts by weight, 28 parts by weight, 30 parts by weight, 32 parts by weight, 35 parts by weight, 38 parts by weight or 40 parts by weight, as well as specific values ​​between the above points. Due to space limitations and for the sake of simplicity, the present invention no longer exhaustively lists the specific points included in the range.

[0068] The content of isocyanate curing agent Y is 15-25 parts by weight, for example, it can be 15 parts by weight, 16 parts by weight, 17 parts by weight, 18 parts by weight, 19 parts by weight, 20 parts by weight, 22 parts by weight or 25 parts by weight, as well as specific values ​​between the above points. Due to space limitations and for the sake of simplicity, the present invention no longer exhaustively lists the specific points included in the range.

[0069] The content of the silane coupling agent is 0-5 parts by weight, for example, it can be 0 parts by weight, 1 part by weight, 2 parts by weight, 3 parts by weight, 4 parts by weight or 5 parts by weight, as well as specific values ​​between the above points. Due to space limitations and for the sake of simplicity, the present invention no longer exhaustively lists the specific points included in the range.

[0070] In a second aspect, the present invention provides a method for preparing the two-component sealant as described in the first aspect, the preparation method comprising the following steps:

[0071] (1) stirring components including an amino resin to obtain component A;

[0072] (2) mixing components including an isocyanate curing agent X and an isocyanate curing agent Y to obtain the component B;

[0073] There is no particular order in which steps (1) and (2) are performed.

[0074] Preferably, the stirring speed in step (1) is 600 r / min.

[0075] Preferably, the stirring time in step (1) is 10-60 min, for example, it can be 10 min, 20 min, 30 min, 40 min, 50 min or 60 min, as well as specific point values ​​between the above point values. Due to space limitations and for the sake of simplicity, the present invention no longer exhaustively lists the specific point values ​​included in the range.

[0076] Preferably, the mixing in step (2) is carried out under stirring.

[0077] Preferably, the stirring speed is 200 r / min.

[0078] Preferably, the mixing time is 15-30 min, for example, it can be 15 min, 17 min, 20 min, 22 min, 25 min, 28 min or 30 min, as well as specific point values ​​between the above point values. Due to space limitations and for the sake of simplicity, the present invention no longer exhaustively lists the specific point values ​​included in the range.

[0079] In the present invention, firstly, component A and component B are prepared separately according to a specific preparation method. When storing, component A and component B are stored separately; when using, component A and component B are directly blended to obtain a two-component sealant with good operability.

[0080] Exemplarily, the preparation method of the two-component sealant of the present invention specifically comprises the following steps:

[0081] (1) Preparation of component A:

[0082] The amino resin, plasticizer and dehydrating agent are mixed and stirred for 5-15 minutes, carbon black, filler, defoamer and antioxidant are added, mixed and stirred for 25-35 minutes, and the stirring is continued for 3-8 minutes under a vacuum degree of >0.095 MPa to obtain the component A.

[0083] (2) Preparation of component B:

[0084] Under a nitrogen atmosphere, isocyanate curing agent X, isocyanate curing agent Y and silane coupling agent are mixed and stirred for 15-25 minutes, and then stirred for 3-8 minutes under a vacuum degree of >0.095 MPa to obtain a clear and transparent component B.

[0085] Preferably, when the two-component sealant is used, component A and component B are first mixed and then cured at room temperature.

[0086] In the present invention, the weight proportions of the components A and B when mixed are calculated according to the component ratios in the above-mentioned formulas of the components A and B.

[0087] Preferably, the room temperature refers to a temperature of 10-30°C, for example, it can be 10°C, 12°C, 14°C, 16°C, 18°C, 20°C, 22°C, 24°C, 26°C, 28°C or 30°C, as well as specific point values ​​between the above point values. Due to space limitations and for the sake of simplicity, the present invention no longer exhaustively lists the specific point values ​​included in the range.

[0088] Preferably, the curing time is 3-7 days, for example, 3 days, 4 days, 5 days, 6 days or 7 days, as well as specific point values ​​between the above point values. Due to space limitations and for the sake of simplicity, the present invention no longer exhaustively lists the specific point values ​​included in the range.

[0089] In a third aspect, the present invention provides an application of the two-component sealant as described in the first aspect in photovoltaic sealing, new energy power station maintenance, automobile chassis sealing or electronic potting.

[0090] Compared with the prior art, the present invention has at least the following beneficial effects:

[0091] (1) The present invention uses amino resin as a raw material to form component A, and uses isocyanate curing agent X and isocyanate curing agent Y as raw materials to form component B, so that the obtained two-component sealant has excellent water vapor barrier and thermal stability. At the same time, it has high strength, good resilience, and excellent water resistance and UV resistance. It has obvious advantages in thermal application scenarios with high requirements for water vapor barrier, such as encapsulating photovoltaic modules and motor sealing.

[0092] (2) The present invention further optimizes the specific raw material selection of component A and component B, so that the water vapor transmission rate of the obtained two-component sealant is less than 10g / (m 2 ·day), when used in photovoltaic modules, it can provide good water-proof protection for internal materials, thereby effectively extending the service life of photovoltaic modules. DETAILED DESCRIPTION

[0093] For the convenience of understanding the present invention, the present invention lists the following embodiments. It should be understood by those skilled in the art that the embodiments are only to help understand the present invention and should not be regarded as specific limitations of the present invention.

[0094] Unless otherwise specified, the raw materials used in the following preparation examples, embodiments and comparative examples are commercially available. Information on some of the raw materials is as follows:

[0095] Amino resins: NH1420, NH2850, NH1220, all purchased from Covestro DESMOPHEN;

[0096] Isocyanate curing agent X: HDI trimer, Wanhua Chemical WANNATE HT-300;

[0097] Liquid hydrogenated carbon nine petroleum resin: purchased from Huntsman, brand name Regalite 1010;

[0098] Cashew nut shell liquid diluent: purchased from Cardolite, brand NX2026;

[0099] Dewatering agent: 4A molecular sieve, purchased from Dalian Haixin, brand HX-104;

[0100] Carbon black: purchased from Cabot, brand N330;

[0101] Surface-modified aluminum hydroxide: purchased from Foshan Huaya Nano New Materials, brand KA-5D;

[0102] Surface modified calcium carbonate: purchased from Omya, brand name omyacarb 5T-JI;

[0103] Surface-modified alumina: purchased from Foshan Huaya Nano New Materials, brand MK-35;

[0104] Surface-modified magnesium hydroxide: purchased from Anhui Yishitong, brand JMTH-02;

[0105] Surface-modified kaolin: purchased from Shanghai Yantai, brand C-96;

[0106] Defoaming agent: purchased from Mingling, Germany, brand A201;

[0107] Hindered phenol antioxidant: purchased from Taiwan Double Bond Chemical, brand name CHINOX 1010;

[0108] Phosphite antioxidant: purchased from Taiwan Double Bond Chemical, brand name CHINOX 168.

[0109] Preparation Example 1

[0110] This preparation example provides an isocyanate curing agent Y, and the preparation method thereof comprises the following steps:

[0111] 435 g of IPDI was weighed, and in a nitrogen atmosphere, an external heat source was set at 50° C., and 250 g of di-n-butylamine soaked in molecular sieves for 24 hours was added dropwise to the IPDI, wherein the molar ratio of IPDI to di-n-butylamine was 1.01:1. After the addition was completed, the isocyanate curing agent Y was obtained.

[0112] Preparation Example 2

[0113] This preparation example provides an isocyanate curing agent Y, and the preparation method thereof comprises the following steps:

[0114] Weigh 230g HDI, add 250g di-n-hexylamine dried at 120°C for 2h in a nitrogen atmosphere with an external heat source at 40°C, wherein the molar ratio of HDI to di-n-hexylamine is 1.01:1. After the addition is completed, the isocyanate curing agent Y is obtained.

[0115] Preparation Example 3

[0116] This preparation example provides an isocyanate curing agent Y, and the preparation method thereof comprises the following steps:

[0117] 293 g of TMDI was weighed, and in a nitrogen atmosphere, an external heat source was set at 40° C., and 250 g of dicyclohexylamine that had been vacuum dried at 120° C. for 2 h was added dropwise to the TMDI. The molar ratio of TMDI to dicyclohexylamine was 1.01:1. After the addition was completed, the isocyanate curing agent Y was obtained.

[0118] Preparation Example 4

[0119] This preparation example provides an isocyanate curing agent Y, and the preparation method thereof comprises the following steps:

[0120] 355 g of TMDI was weighed, and 250 g of di-n-hexylamine dried at 120° C. in vacuum for 2 h was added dropwise to the TMDI in a nitrogen atmosphere with an external heat source at 40° C. The molar ratio of TMDI to di-n-hexylamine was 1.25:1. After the addition was completed, the isocyanate curing agent Y was obtained.

[0121] Example 1

[0122] This embodiment provides a two-component sealant, and the preparation method thereof comprises the following steps:

[0123] (1) Preparation of component A:

[0124] 60 parts by weight of amino resin (NH1420), 5 parts by weight of liquid hydrogenated carbon nine petroleum resin, and 5 parts by weight of dewatering agent were mixed and stirred for 10 minutes, and 1 part by weight of carbon black, 28 parts by weight of surface-modified aluminum hydroxide (average particle size of 5 μm), 0.15 parts by weight of defoamer, 0.4 parts by weight of hindered phenol antioxidant, and 0.4 parts by weight of phosphite antioxidant were added and mixed and stirred for 30 minutes. Stirring was continued for 5 minutes under a vacuum degree of 100 KPa to obtain a black component A, whose room temperature viscosity was 5500 mPa·s.

[0125] (2) Preparation of component B:

[0126] Under nitrogen atmosphere, 28 parts by weight of HDI trimer, 22 parts by weight of isocyanate curing agent Y (Preparation Example 1) and 4 parts by weight of 3-isocyanate propyl trimethoxy silane were mixed and stirred for 20 minutes. Stirring was continued for 5 minutes under a vacuum degree of 100 KPa to obtain a clear and transparent component B with a room temperature viscosity of 1000 mPa·s.

[0127] Example 2

[0128] This embodiment provides a two-component sealant, and the preparation method thereof comprises the following steps:

[0129] Step (1) has the same raw materials, content and preparation method as those in Example 1;

[0130] (2) Preparation of component B:

[0131] Under nitrogen atmosphere, 28 parts by weight of HDI trimer, 22 parts by weight of isocyanate curing agent Y (obtained from Preparation Example 2) and 4 parts by weight of 3-isocyanate propyl trimethoxy silane were mixed and stirred for 20 minutes. Stirring was continued for 5 minutes under a vacuum degree of 100 KPa to obtain a clear and transparent component B. Its room temperature viscosity was 950 mPa·s.

[0132] Example 3

[0133] This embodiment provides a two-component sealant, and the preparation method thereof comprises the following steps:

[0134] (1) Preparation of component A:

[0135] 65 parts by weight of amino resin (NH1420), 5 parts by weight of cashew nut shell oil diluent, and 5 parts by weight of dewatering agent were mixed and stirred for 10 minutes, and 1 part by weight of carbon black, 15 parts by weight of surface-modified calcium carbonate (average particle size of 5 μm), 8 parts by weight of surface-modified aluminum oxide (average particle size of 5 μm), 0.15 parts by weight of defoamer, 0.4 parts by weight of hindered phenol antioxidant, and 0.4 parts of phosphite antioxidant were added, and mixed and stirred for 30 minutes. Stirring was continued for 5 minutes under a vacuum degree of 100 KPa to obtain a black component A, whose room temperature viscosity was 4000 mPa·s.

[0136] (2) Preparation of component B:

[0137] Under nitrogen atmosphere, 35 parts by weight of HDI trimer, 23 parts by weight of isocyanate curing agent Y (Preparation Example 3) and 2 parts by weight of 3-glycidyloxypropyltrimethoxysilane were mixed and stirred for 20 minutes. Stirring was continued for 5 minutes under a vacuum degree of 100 KPa to obtain a clear and transparent component B, whose room temperature viscosity was 750 mPa·s.

[0138] Example 4

[0139] This embodiment provides a two-component sealant, and the preparation method thereof comprises the following steps:

[0140] (1) Preparation of component A:

[0141] 60 parts by weight of amino resin (NH1420), 4 parts by weight of 2,6-diisopropylnaphthalene, and 5 parts by weight of dewatering agent were mixed and stirred for 10 minutes, and 1 part by weight of carbon black, 29 parts by weight of surface-modified magnesium hydroxide (average particle size of 5 μm), 0.15 parts by weight of defoamer, 0.4 parts by weight of hindered phenol antioxidant, and 0.4 parts by weight of phosphite antioxidant were added and mixed and stirred for 30 minutes. Stirring was continued for 5 minutes under a vacuum degree of 100 KPa to obtain a black component A, whose room temperature viscosity was 4100 mPa·s.

[0142] The raw materials, contents and preparation methods of step (2) are the same as those of Example 1.

[0143] Example 5

[0144] This embodiment provides a two-component sealant, and the preparation method thereof comprises the following steps:

[0145] (1) Preparation of component A:

[0146] 60 parts by weight of amino resin (NH1420), 4 parts by weight of 2,6-diisopropylnaphthalene, and 5 parts by weight of dewatering agent were mixed and stirred for 10 minutes, and 1 part by weight of carbon black, 29 parts by weight of magnesium hydroxide (average particle size of 5 μm), 0.15 parts by weight of defoamer, 0.4 parts by weight of hindered phenol antioxidant, and 0.4 parts by weight of phosphite antioxidant were added and mixed and stirred for 30 minutes. Stirring was continued for 5 minutes under a vacuum degree of 100 KPa to obtain a black component A, whose room temperature viscosity was 5300 mPa·s.

[0147] (2) Preparation of component B:

[0148] Under nitrogen atmosphere, 33 parts by weight of HDI trimer, 15 parts by weight of isocyanate curing agent Y (Preparation Example 4), and 3 parts of 3-isocyanate propyl triethoxysilane were mixed and stirred for 20 minutes. Stirring was continued for 5 minutes under a vacuum degree of 100 KPa to obtain a clear and transparent component B. Its room temperature viscosity was 500 mPa·s.

[0149] Example 6

[0150] This embodiment provides a two-component sealant, and the preparation method thereof comprises the following steps:

[0151] (1) Preparation of component A:

[0152] 70 parts by weight of amino resin (NH1420), 5 parts by weight of 2,6-diisopropylnaphthalene, and 5 parts by weight of dewatering agent were mixed and stirred for 10 minutes, and 1 part by weight of carbon black, 20 parts by weight of surface-modified kaolin (average particle size of 5 μm), 0.15 parts by weight of defoamer, 0.4 parts by weight of hindered phenol antioxidant, and 0.4 parts by weight of phosphite antioxidant were added and mixed and stirred for 30 minutes. Stirring was continued for 5 minutes under a vacuum degree of 100 KPa to obtain a black component A, whose room temperature viscosity was 3200 mPa·s.

[0153] (2) Preparation of component B:

[0154] 38 parts by weight of HDI trimer, 22 parts by weight of isocyanate curing agent Y (Preparation Example 1), and 3 parts by weight of 3-isocyanate propyl triethoxy silane were mixed and stirred for 20 minutes. Stirring was continued for 5 minutes under a vacuum degree of 100 KPa to obtain a clear and transparent component B, whose room temperature viscosity was 800 mPa·s.

[0155] Example 7

[0156] This embodiment provides a two-component sealant, and the preparation method thereof comprises the following steps:

[0157] (1) Preparation of component A:

[0158] 75 parts by weight of amino resin (NH1420), 8 parts by weight of liquid hydrogenated carbon nine petroleum resin, and 5 parts by weight of dewatering agent were mixed and stirred for 15 minutes, and 1.5 parts by weight of carbon black, 60 parts by weight of surface-modified aluminum hydroxide (average particle size of 5 μm), 0.2 parts by weight of defoamer, 4 parts by weight of hindered phenol antioxidant, and 4 parts by weight of phosphite antioxidant were added and mixed and stirred for 35 minutes. Stirring was continued for 8 minutes under a vacuum degree of 100 KPa to obtain a black component A, whose room temperature viscosity was 6600 mPa·s.

[0159] (2) Preparation of component B:

[0160] Under nitrogen atmosphere, 40 parts by weight of HDI trimer, 25 parts by weight of isocyanate curing agent Y (Preparation Example 1) and 5 parts by weight of 3-isocyanate propyl trimethoxy silane were mixed and stirred for 25 minutes. Stirring was continued for 8 minutes under a vacuum degree of 100 KPa to obtain a clear and transparent component B, whose room temperature viscosity was 760 mPa·s.

[0161] Example 8

[0162] This embodiment provides a two-component sealant, and the preparation method thereof comprises the following steps:

[0163] (1) Preparation of component A:

[0164] 55 parts by weight of amino resin (NH1420) and 20 parts by weight of aluminum hydroxide were mixed and stirred for 25 minutes, and stirred for 8 minutes under a vacuum degree of 100 KPa to obtain the component A, whose room temperature viscosity was 3500 mPa·s.

[0165] (2) Preparation of component B:

[0166] Under nitrogen atmosphere, 25 parts by weight of HDI trimer and 15 parts by weight of isocyanate curing agent Y (Preparation Example 1) were mixed and stirred for 15 minutes, and stirred for 3 minutes under a vacuum degree of 100 KPa to obtain a clear and transparent component B with a room temperature viscosity of 980 mPa·s.

[0167] Example 9

[0168] This embodiment provides a two-component sealant, which differs from Embodiment 1 only in that the amino resin (NH1420) in step (1) is replaced by an amino resin (NH2850) of equal mass, and other raw materials, contents and preparation methods are the same as those in Embodiment 1.

[0169] Example 10

[0170] This embodiment provides a two-component sealant, which differs from Embodiment 1 only in that the amino resin (NH1420) in step (1) is replaced by amino resin (NH1220), and other raw materials, contents and preparation methods are the same as those in Embodiment 1.

[0171] Embodiment 11

[0172] This embodiment provides a two-component sealant, which differs from Embodiment 1 only in that liquid hydrogenated carbon nine petroleum resin is not added in step (1), and other raw materials, contents and preparation methods are the same as those in Embodiment 1.

[0173] Example 12

[0174] This embodiment provides a two-component sealant, which differs from Embodiment 1 only in that the liquid hydrogenated carbon nine petroleum resin in step (1) is replaced by an equal mass of diisononyl phthalate (DINP), and the other raw materials, contents and preparation methods are the same as those in Embodiment 1.

[0175] Embodiment 13

[0176] This embodiment provides a two-component sealant, which differs from Example 1 in that the content of HDI trimer in step (2) is adjusted from 28 parts by weight to 36.5 parts by weight, and the content of isocyanate curing agent Y (Preparation Example 1) is adjusted from 22 parts by weight to 13.5 parts by weight, and other raw materials, contents and preparation methods are the same as those in Example 1.

[0177] Embodiment 14

[0178] This embodiment provides a two-component sealant, which differs from Example 1 in that the content of HDI trimer in step (2) is adjusted from 28 parts by weight to 34.2 parts by weight, and the content of isocyanate curing agent Y (Preparation Example 1) is adjusted from 22 parts by weight to 15.8 parts by weight, and other raw materials, contents and preparation methods are the same as those in Example 1.

[0179] Embodiment 15

[0180] This embodiment provides a two-component sealant, which differs from Example 1 in that the content of HDI trimer in step (2) is adjusted from 28 parts by weight to 26.3 parts by weight, and the content of isocyanate curing agent Y (Preparation Example 1) is adjusted from 22 parts by weight to 23.7 parts by weight, and other raw materials, contents and preparation methods are the same as those in Example 1.

[0181] Comparative Example 1

[0182] This comparative example provides a two-component sealant, which adopts a two-component vulcanized silicone rubber sealing system.

[0183] (1) Preparation of component A:

[0184] 150 parts by weight of α,ω-dihydroxy polydimethylsiloxane (purchased from Guangdong Chensi CX-107, with a viscosity of 2000 mPa·s at 25°C) and 15 parts by weight of dimethyl silicone oil (purchased from Zhejiang Zhenghe 201-100, with a viscosity of 100 mPa·s at 25°C) were mixed, and 60 parts by weight of surface-modified aluminum hydroxide (average particle size of 5 μm) were mixed and stirred for 20 minutes. The mixture was stirred for 5 minutes under a vacuum degree of 100 KPa to obtain the component A;

[0185] (2) Preparation of component B:

[0186] Under nitrogen protection, 15 parts by weight of dimethyl silicone oil (purchased from Zhejiang Zhenghe 201-100, with a viscosity of 100 mPa·s at 25°C), 1 part by weight of tetraethoxysilane, 4 parts by weight of methyltrimethoxysilane, 3 parts by weight of γ-aminopropyltriethoxysilane, 3 parts by weight of γ-(2,3-epoxypropoxy)propyltrimethoxysilane, and 1 part by weight of dibutyltin dilaurate were mixed and stirred for 20 minutes, and stirred for 5 minutes under a vacuum degree of 100 KPa to obtain the component B.

[0187] Comparative Example 2

[0188] This embodiment provides a two-component sealant, which differs from Example 1 only in that isocyanate curing agent Y (Preparation Example 1) is not added in step (2), the content of HDI trimer is adjusted from 28 parts by weight to 50 parts by weight, and other raw materials, contents and preparation methods are the same as those in Example 1.

[0189] Component A and component B of the two-component sealant in the above Examples 1-15 and Comparative Examples 1-2 were mixed to pot the photovoltaic junction box, and the performance test was performed after curing at 25° C. for seven days. The test method / standard is as follows:

[0190] (1) Density: refer to GB / T 13354;

[0191] (2) Mixed viscosity: refer to GB / T 2794-2013;

[0192] (3) Room temperature gel time: The time from mixing to the time when the glue stops flowing horizontally when poured into a container with an inner diameter of 4 cm and a depth of 20 cm under the conditions of 23±2°C and 50±5% RH;

[0193] (4) Thermal conductivity: refer to GB / T 11205;

[0194] (5) Tensile elastic modulus: refer to GB / T 528-2009;

[0195] (6) Flame retardant grade: refer to UL94 standard test;

[0196] (7) Volume resistivity: refer to GB / T 1692-2008;

[0197] (8) Breakdown voltage: refer to GB / T 1695-2005;

[0198] (9) Water vapor transmission value: The water vapor transmission rate through a 1 mm thick film is measured at 38°C and 90% RH.

[0199] (10) Adhesion performance: Test the adhesion performance with polyphenylene ether (PPO) at 85°C and 85% RH for 1000 h (cohesive failure 100%);

[0200] (11) Diode power-on heating simulation: Connect the positive and negative poles of the diode and pass a current of 30A for 1 hour. The junction temperature of the diode stabilizes at 190-200°C. At this temperature, the sealant is tested for heat resistance to check whether the sealant sample has any appearance defects such as cracking, bulging, and cracks.

[0201] The test results are shown in Table 1.

[0202] Table 1

[0203]

[0204]

[0205] The test results show that:

[0206] (1) It can be seen from Examples 1 to 15 that the present invention uses amino resin as a raw material to form component A and uses isocyanate curing agent X and isocyanate curing agent Y as raw materials to form component B, so that the obtained two-component sealant has excellent water vapor barrier properties. At the same time, it has high strength, good resilience, and excellent water resistance and UV resistance.

[0207] (2) By comparing Example 1 with Examples 9 and 10, it can be seen that the present invention can adjust the room temperature gel time of the obtained two-component sealant by further optimizing the type of amino resin in component A, and at the same time, it can also effectively improve the water vapor barrier property of the obtained two-component sealant.

[0208] (3) It can be seen from Example 1 and Examples 11 and 12 that the addition of a specific plasticizer in Component A of the present invention can further improve the water vapor barrier performance of the obtained two-component sealant, and no debonding occurs in the diode power-on heating simulation, and the heat resistance and adhesion are good.

[0209] (4) By comparing Examples 1 and 13-15, it can be seen that the present invention can improve the mechanical properties of the obtained two-component sealant by optimizing the mass ratio of isocyanate curing agent X and isocyanate curing agent Y in component B, and at the same time has a certain influence on its water vapor barrier performance. The mass ratio of the two in component B of Example 13 is higher than 1:0.46, that is, the proportion of isocyanate curing agent Y is too low, the cross-linking density of the colloid is too high, the tensile modulus is large, the resilience is poor, and the water vapor barrier property is slightly poor. The mass ratio of the two in component B of Example 15 is lower than 1:0.8, that is, the proportion of isocyanate curing agent Y is too high, the cross-linking density of the colloid is too low, and the heat resistance is insufficient.

[0210] (5) By comparing Example 1 with Comparative Example 1, it can be seen that the two-component sealant provided by the present invention has excellent water vapor barrier properties.

[0211] (6) By comparing Example 1 with Comparative Example 2, it can be seen that the present invention can obtain a better technical effect of resilience by using isocyanate curing agents X and Y in combination, and no debonding occurs in the diode power-on heating simulation; when the isocyanate curing agent Y is missing, its tensile modulus is as high as 1480 MPa, the resilience is poor, and debonding occurs in the diode power-on heating simulation, and it exhibits slightly poor water vapor barrier properties.

[0212] In summary, the present invention uses amino resin as a raw material to form component A, and uses isocyanate curing agent X and isocyanate curing agent Y as raw materials to form component B, so that the obtained two-component sealant has excellent water vapor barrier and thermal stability; at the same time, it has high strength, good resilience, and excellent water resistance and UV resistance. It has obvious advantages in thermal application scenarios with high requirements for water vapor barrier, such as encapsulating photovoltaic modules and motor sealing.

[0213] The applicant declares that the above is only a specific implementation mode of the present invention, but the protection scope of the present invention is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed by the present invention shall fall within the protection scope and disclosure scope of the present invention.

Claims

1. A two-component sealant, characterized in that: The two-component sealant comprises component A and component B; the component A comprises amino resin; and the component B comprises isocyanate curing agent X and isocyanate curing agent Y.

2. The two-component sealant according to claim 1, characterized in that: The amino resin includes polyaspartic acid ester; Preferably, the polyaspartic acid ester has a structure shown in formula (I): Wherein, R1, R2, R3, and R4 are each independently selected from one or more of substituted or unsubstituted C1-C18 alkyl, substituted or unsubstituted C6-C18 aryl, and substituted or unsubstituted C2-C16 hydrocarbon groups; the substituents include H, halogen, or C1-C5 alkyl; X is selected from Any one of the groups, preferably 3. The two-component sealant according to claim 1 or 2, characterized in that: The mass ratio of the isocyanate curing agent X to the isocyanate curing agent Y is 1:(0.37-1), preferably 1:(0.46-0.8); Preferably, the isocyanate curing agent X comprises HDI trimer and / or HDI biuret; Preferably, the isocyanate curing agent Y is an isocyanate adduct of a monofunctional amine; Preferably, the isocyanate adduct of the monofunctional amine is obtained by reacting a monofunctional amine with an isocyanate; Preferably, the molar ratio of isocyanate to monofunctional amine in the reaction is (1.01-1.25):1; Preferably, the isocyanate comprises an aliphatic difunctional isocyanate; Preferably, the aliphatic difunctional isocyanate includes any one or a combination of at least two of hexamethylene diisocyanate, isophorone diisocyanate, dicyclohexylmethane-4,4'-diisocyanate, 1,4-cyclohexane diisocyanate, hydrogenated xylylene diisocyanate, methylcyclohexane diisocyanate, trimethylhexamethylene diisocyanate or 1,5-pentane diisocyanate; Preferably, the monofunctional amine comprises a monofunctional secondary amine; Preferably, the monofunctional secondary amine includes any one of di-n-butylamine, di-n-hexylamine, dioctylamine or dicyclohexylamine, or a combination of at least two thereof.

4. The two-component sealant according to any one of claims 1 to 3, characterized in that: The component A also includes a plasticizer; Preferably, the plasticizer includes any one of liquid carbon nine petroleum resin, liquid hydrogenated carbon nine petroleum resin, cashew nut shell oil diluent or 2,6-diisopropylnaphthalene, or a combination of at least two thereof.

5. The two-component sealant according to any one of claims 1 to 4, characterized in that: The component A further comprises any one or a combination of at least two of a dewatering agent, carbon black, a filler, a defoaming agent or an antioxidant; Preferably, the dehydrating agent comprises 4A molecular sieve; Preferably, the carbon black comprises specialty carbon black; Preferably, the filler comprises a surface-modified or unmodified filler; Preferably, the filler comprises any one or a combination of at least two of calcium carbonate, boehmite, aluminum hydroxide, aluminum oxide, magnesium hydroxide, kaolin, silica powder, mica powder or talc; Preferably, the defoaming agent comprises a polysiloxane defoaming agent; Preferably, the antioxidant includes any one of a hindered phenol antioxidant, an aromatic secondary amine antioxidant, a phosphite antioxidant or a thioether antioxidant, or a combination of at least two thereof.

6. The two-component sealant according to any one of claims 1 to 5, characterized in that: The component A comprises the following components in parts by weight:

7. The two-component sealant according to any one of claims 1 to 6, characterized in that: The component B also includes a coupling agent; Preferably, the coupling agent comprises a silane coupling agent.

8. The two-component sealant according to any one of claims 1 to 7, characterized in that: The component B comprises the following components in parts by weight: Isocyanate curing agent X 25-40 parts by weight Isocyanate curing agent Y 15-25 parts by weight Coupling agent 0-5 parts by weight 9. A method for preparing a two-component sealant according to any one of claims 1 to 8, characterized in that: The preparation method comprises the following steps: (1) preparing component A: stirring components including an amino resin to obtain component A; (2) preparing component B: mixing components including isocyanate curing agent X and isocyanate curing agent Y to obtain component B; There is no particular order in which steps (1) and (2) are performed.

10. Use of the two-component sealant according to any one of claims 1 to 8 in photovoltaic sealing, new energy power station maintenance, automobile chassis sealing or electronic potting.

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