CN118421245B - A sealant composition and its preparation method and application - Google Patents

Abstract

The present invention relates to a sealant composition and a preparation method and application thereof, and belongs to the technical field of sealants. The sealant composition of the present invention comprises 5-40 parts of a bifunctional epoxy resin, 20-60 parts of a vinyl composition, 0.1-3 parts of a photoinitiator, 0.1-3 parts of a coupling agent, 0.1-5 parts of a curing agent, and 1-15 parts of a filler in parts by mass; the vinyl composition comprises an acrylic modified epoxy resin, an acrylate oligomer, and an aliphatic epoxy resin; wherein m and n are independently integers of 1-4; X, Y, and Z are independently selected from hydrogen or methyl; R is selected from hydrogen or an alkyl group of C1-C7, and p and q are independently integers of 2-20. The sealant composition is rapidly pre-cured during UV curing, which can ensure good adhesion of the sealant and has excellent high temperature and humidity resistance.

Description

A sealant composition and its preparation method and application

Technical Field

The present invention belongs to the technical field of sealants, and in particular relates to a sealant composition and a preparation method and application thereof.

Background Art

As customers' requirements for liquid crystal displays continue to increase and the size of displays continues to increase, in the fifth generation and above LCD packaging processes, the liquid crystal drop (ODF) process has become a trend due to its advantages such as simplified process, short process time and high liquid crystal utilization rate. At present, the mainstream ODF process uses a combination of photothermal curing and adhesive. UV light curing is used in the early stage of the application process to effectively avoid the contamination of the frame glue on the liquid crystal; then heat curing is performed to provide high adhesion. In the ODF process, UV glue usually uses a free radical initiator to induce the polymerization reaction of acrylic resin, and thermal curing is mainly the reaction of epoxy resin and thermal curing agent to form an adhesive film. Therefore, there are strict requirements for the adhesion, high temperature and high humidity resistance, and liquid crystal contamination of the sealant used for liquid crystal display elements.

Patent CN 116790214 A uses high Tg bifunctional epoxy resin and monofunctional acrylic resin as main materials, and adds photoinitiator, coupling agent, curing agent and filler to prepare a sealant composition. However, UV curing and thermal curing react separately, and the molecular chain exists only in the form of long chains, and the density of the film is insufficient.

Patent CN 102197334 A uses a resin having a methacryloyl group with a weight fraction of more than 50% for curing reaction. The resin reacts only during UV curing, and the molecular chain exists only in the form of a long chain of multiple benzene rings. The film is not dense enough, has weak resistance to high temperature and high humidity, and has no soft segments. The overall film is brittle and has poor applicability.

Acrylic modified epoxy resin is often used in the industry to achieve a combination of UV curing and thermal curing. However, acrylic modified epoxy resin has a relatively simple structure, limited cross-linking density, and often contains benzene ring structures. The film is brittle and lacks flexibility, making it difficult to achieve a balance between high adhesion and resistance to high temperature and humidity.

Summary of the invention

In order to solve the above technical problems, the present invention provides a sealant composition and a preparation method and application thereof. The sealant composition adopts a vinyl composition composed of an acrylic acid-modified epoxy resin, an acrylate oligomer having an aliphatic ring and a soft segment, and an aliphatic epoxy resin in a certain ratio. The sealant composition is quickly pre-cured during UV curing. The UV curing segment has epoxy groups of different chain lengths. In the thermal curing stage, it can form a dense network structure with a thermal curing agent, and the molecular chain contains a soft segment, which can ensure good adhesion of the sealant and have excellent high temperature and humidity resistance.

The first object of the present invention is to provide a sealant composition, which comprises, by mass, 5-40 parts of a bifunctional epoxy resin, 20-60 parts of a vinyl composition, 0.1-3 parts of a photoinitiator, 0.1-3 parts of a coupling agent, 0.1-5 parts of a curing agent and 1-15 parts of a filler; the vinyl composition comprises an acrylic modified epoxy resin, an acrylic ester oligomer and an aliphatic epoxy resin; the structures of the acrylic modified epoxy resin, the acrylic ester oligomer and the aliphatic epoxy resin are shown in Formula I, Formula II and Formula III, respectively:

,

,

;

Wherein, m and n are independently integers of 1-4;

X, Y, and Z are independently selected from hydrogen or methyl; R is selected from hydrogen or C1-C7 alkyl, and p and q are independently integers of 2-20.

In one embodiment of the present invention, the acrylic oligomer has aliphatic rings and soft segments, which achieves a good balance between rigidity and flexibility, that is, a balance between strength and adhesive force.

Furthermore, based on parts by mass, it includes 15-30 parts of a bifunctional epoxy resin, 25-50 parts of a vinyl composition, 0.5-2 parts of a photoinitiator, 0.5-2 parts of a coupling agent, 0.1-5 parts of a curing agent and 5-15 parts of a filler.

In one embodiment of the present invention, the mass ratio of the acrylic modified epoxy resin, the acrylic ester oligomer and the aliphatic epoxy resin is (4-8): (4-12): (2-10).

Furthermore, the mass ratio of the acrylic modified epoxy resin, the acrylic ester oligomer and the aliphatic epoxy resin is (5-7): (6-11): (2-6).

In one embodiment of the present invention, the preparation of the acrylic acid-modified epoxy resin specifically comprises the following steps: dissolving a first antioxidant and a first polymerization inhibitor in a first solvent, heating to 80°C-100°C, and continuously adding an epoxy resin of formula IV, acrylic acid and a first catalyst to react at 120°C-150°C for 3h-8h to obtain the acrylic acid-modified epoxy resin; the structure of the epoxy resin is shown in formula IV:

,

Here, m is an integer from 1 to 4.

In one embodiment of the present invention, the first antioxidant is 2,6-di-tert-butyl-p-cresol; the first inhibitor is p-hydroxyanisole; the first catalyst is selected from triphenylphosphine and/or tetrabutylphosphine chloride; and the first solvent is selected from diethylene glycol monoethyl ether acetate and/or dipropylene glycol monomethyl ether.

In one embodiment of the present invention, the preparation of the acrylate oligomer specifically comprises the following steps: dropwise adding an acrylate monomer solution and an initiator solution into a second solvent at 100°C-120°C for reaction, then cooling to 70°C-100°C, and continuously adding a second antioxidant, a second polymerization inhibitor, a second catalyst and an aliphatic epoxy resin of formula III for reaction at 100°C-130°C for 6h-12h to obtain the acrylate oligomer; the acrylate monomer comprises a first monomer and a second monomer; the first monomer is selected from methacrylic acid and/or acrylic acid; the structure of the second monomer is as shown in formula V:

,

Wherein, X is selected from hydrogen or methyl; R is selected from hydrogen or C1-C7 alkyl.

In one embodiment of the present invention, the second antioxidant is 2,6-di-tert-butyl-p-cresol; the second inhibitor is p-hydroxyanisole; the second catalyst is selected from triphenylphosphine and/or tetrabutylphosphine chloride; and the second solvent is selected from diethylene glycol monoethyl ether acetate and/or dipropylene glycol monomethyl ether.

In one embodiment of the present invention, the initiator is dibenzoyl peroxide.

In one embodiment of the present invention, the bifunctional epoxy resin is selected from one or more of bisphenol A epoxy resin, bisphenol F epoxy resin and bisphenol S epoxy resin; the photoinitiator is selected from diphenyl-2,4,6-trimethylbenzoylphosphine oxide, bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide, 2-benzyl-2-(dimethylamino)-1-[4-(4-morpholinyl)phenyl]-1-butanone, benzoin isopropyl ether, 2-hydroxy-2-methyl-1-phenylpropane-1-one, 2-hydroxy-2-methyl-1-phenylacetone, 2,2-dimethoxy-2-phenylacetophenone, 2-ethylanthraquinone, 2-dichlorobenzophenone, p-dimethylaminobenzoate and benzyl dimethyl ketal. One or more of; the coupling agent is selected from one or more of γ-glycidyloxypropyltrimethoxysilane, γ-aminopropyltriethoxysilane, γ-methacryloxypropyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, vinyltrimethoxysilane and N-βaminoethyl-γ-aminopropyltrimethoxysilane; the curing agent is selected from one or more of organic acid hydrazides, imidazole derivatives, amine compounds and acid anhydrides; the curing agent is a latent thermal curing agent, which can ensure that the epoxy resin has good storage stability at low temperatures, and can react quickly after the temperature rises to a certain level, so that the epoxy resin can be quickly cross-linked and cured; the filler is selected from one or more of diatomaceous earth, silicon dioxide, calcium carbonate and talc.

The second object of the present invention is to provide a method for preparing the sealant composition, comprising the following steps: uniformly mixing a bifunctional epoxy resin, a vinyl composition, a photoinitiator, a coupling agent, a curing agent and a filler to obtain the sealant composition.

The third object of the present invention is to provide an application of the sealant composition in a liquid crystal display element.

The technical solution of the present invention has the following advantages over the prior art:

The sealant composition of the present invention adopts a vinyl composition containing both vinyl double bonds and epoxy groups (of different chain lengths), which can be quickly fixed during UV pre-curing and react with a curing agent during thermal curing to form a more compact network structure, thereby ensuring excellent high temperature and high humidity resistance. The acrylic modified epoxy resin contains a benzene ring structure, which provides rigid support in the molecular chain, and has excellent heat resistance due to the high _Tg of the acrylic modified epoxy resin. The introduction of acrylic ester oligomers and aliphatic epoxy resins provides a certain flexible structure in the molecular chain, which can well balance the defect of decreased adhesion caused by too much rigid structure of the molecular chain. Since the acrylic ester oligomers and aliphatic epoxy resins have different chain lengths, they can provide adhesion adapted to various curved surfaces, thereby avoiding rupture caused by too brittle film, especially rupture of the film at the bend, which causes air or water vapor to penetrate into the liquid crystal, resulting in defects such as light spots on the product, thereby achieving a balance between adhesion and high temperature and high humidity resistance.

DETAILED DESCRIPTION

The present invention is further described below in conjunction with specific embodiments so that those skilled in the art can better understand the present invention and implement it, but the embodiments are not intended to limit the present invention.

In the present invention, unless otherwise specified, the preparation of the acrylic acid-modified epoxy resin used in the examples and comparative examples specifically includes the following steps: 20 g of diethylene glycol monoethyl ether acetate is added to a 250 mL four-necked flask, 0.5 g of 2,6-di-tert-butyl-p-cresol and 0.05 g of p-hydroxyanisole are added under stirring, the temperature is raised to 100° C., 58 g of epoxy resin (purchased from DIC, brand EPICLON N-680) is added in batches until it is completely dissolved, compressed air is blown in, 11 g of acrylic acid and 0.3 g of triphenylphosphine are added, the temperature is raised to 120° C., the reaction is carried out for 4 hours, and the diethylene glycol monoethyl ether acetate is rotary distilled to obtain an acrylic acid-modified epoxy resin. .

In the present invention, unless otherwise specified, the preparation of the acrylate oligomer used in the examples and comparative examples specifically includes the following steps: adding 20 g of dipropylene glycol monomethyl ether to a 250 mL four-necked flask, stirring and heating to 100° C., and simultaneously dropping a monomer mixture (mixing 28.46 g of methacrylic acid, 12.17 g of acrylic acid and 2 g of dipropylene glycol monomethyl ether) and an initiator solution (mixing 1.3 g of dibenzoyl peroxide and 4 g of dipropylene glycol monomethyl ether) under nitrogen protection, and the dropping is completed in 4 hours. After keeping warm for 3 hours, the temperature is lowered to 80° C., and 0.14 g of 2,6-di-tert-butyl-p-cresol and 0.036 g of p-hydroxyanisole are continuously added, compressed air is blown in, 30.90 g of 3,4-epoxycyclohexyl methacrylate and 0.22 g of tetrabutylphosphine chloride are added, the temperature is raised to 110° C., reacted for 10 hours, and dipropylene glycol monomethyl ether is rotary distilled to obtain an acrylate oligomer. .

In the present invention, unless otherwise stated, the information of the experimental raw materials used in the examples and comparative examples is as follows:

The aliphatic epoxy resin is 3,4-epoxycyclohexyl methacrylate;

Bisphenol A epoxy resin was purchased from Nan Ya Resins, brand 128E;

Bisphenol F epoxy resin was purchased from Changchun Chemical Industry with the brand name BPF170;

Bisphenol S epoxy resin was purchased from DIC with the brand name EPICLON EXA1514;

The photoinitiator was 2-hydroxy-2-methyl-1-phenylpropanone, purchased from Wall-E Technology, brand number 1173;

The coupling agent was γ-glycidyloxypropyltrimethoxysilane, purchased from Momentive, with the brand name A-187;

The curing agent is adipic acid dihydrazide;

The filler is diatomaceous earth;

Acrylic resin is epoxy-modified acrylic resin oligomer purchased from Allnex Corporation with the brand name EB600.

Example 1

The raw material components and their weight parts of the sealant composition of this embodiment are as follows:

40 parts of bisphenol A epoxy resin, 45 parts of vinyl composition, 1.0 parts of photoinitiator, 1.5 parts of coupling agent, 2.5 parts of curing agent, and 10 parts of filler; the weight ratio of acrylic modified epoxy resin, acrylic ester oligomer and aliphatic epoxy resin in the vinyl composition is 7:8:5.

The preparation method specifically comprises the following steps:

S1. Preliminarily mix bisphenol A epoxy resin, vinyl composition, photoinitiator and coupling agent at room temperature, then add filler in batches, mix and stir thoroughly to obtain a mixture;

S2. Grind the mixture with a three-roll grinder until the fineness is less than 5 μm, add a curing agent, continue stirring and mixing until uniform, filter and fill, and obtain a sealant composition.

Example 2 is basically the same as Example 1, except that bisphenol A epoxy resin is replaced by bisphenol F epoxy resin.

The raw material components of the sealant composition and their weight parts are as follows:

40 parts of bisphenol F epoxy resin, 45 parts of vinyl composition, 1.0 parts of photoinitiator, 1.5 parts of coupling agent, 2.5 parts of curing agent, and 10 parts of filler; the weight ratio of acrylic modified epoxy resin, acrylic ester oligomer and aliphatic epoxy resin in the vinyl composition is 7:8:5;

The preparation method of the sealant composition is the same as that of Example 1.

Example 3 is basically the same as Example 1, except that bisphenol A epoxy resin is replaced by bisphenol S epoxy resin.

The raw material components of the sealant composition and their weight parts are as follows:

40 parts of bisphenol S epoxy resin, 45 parts of vinyl composition, 1.0 parts of photoinitiator, 1.5 parts of coupling agent, 2.5 parts of curing agent, and 10 parts of filler; the weight ratio of acrylic acid-modified epoxy resin, acrylic acid ester oligomer and aliphatic epoxy resin in the vinyl composition is 7:8:5;

The preparation method of the sealant composition is the same as that of Example 1.

Example 4 is basically the same as Example 1, except that the bisphenol A epoxy resin is partially replaced by bisphenol F epoxy resin.

The raw material components of the sealant composition and their weight parts are as follows:

20 parts of bisphenol A epoxy resin, 20 parts of bisphenol F epoxy resin, 45 parts of vinyl composition, 1.0 parts of photoinitiator, 1.5 parts of coupling agent, 2.5 parts of curing agent, and 10 parts of filler; the weight ratio of acrylic acid-modified epoxy resin, acrylic acid ester oligomer and aliphatic epoxy resin in the vinyl composition is 7:8:5;

The preparation method of the sealant composition is the same as that of Example 1.

Example 5 is basically the same as Example 1, except for the weight parts of bisphenol A epoxy resin and vinyl composition.

The raw material components of the sealant composition and their weight parts are as follows:

35 parts of bisphenol A epoxy resin, 50 parts of vinyl composition, 1.0 parts of photoinitiator, 1.5 parts of coupling agent, 2.5 parts of curing agent, and 10 parts of filler; the weight ratio of acrylic acid-modified epoxy resin, acrylic acid ester oligomer and aliphatic epoxy resin in the vinyl composition is 7:8:5;

The preparation method of the sealant composition is the same as that of Example 1.

Example 6 is basically the same as Example 1, except for the weight parts of bisphenol A epoxy resin and vinyl composition.

The raw material components of the sealant composition and their weight parts are as follows:

30 parts of bisphenol A epoxy resin, 55 parts of vinyl composition, 1.0 parts of photoinitiator, 1.5 parts of coupling agent, 2.5 parts of curing agent, and 10 parts of filler; the weight ratio of acrylic acid-modified epoxy resin, acrylic acid ester oligomer and aliphatic epoxy resin in the vinyl composition is 7:8:5;

The preparation method of the sealant composition is the same as that of Example 1.

Example 7 is basically the same as Example 1, except for the weight parts of bisphenol A epoxy resin and vinyl composition.

The raw material components of the sealant composition and their weight parts are as follows:

25 parts of bisphenol A epoxy resin, 60 parts of vinyl composition, 1.0 parts of photoinitiator, 1.5 parts of coupling agent, 2.5 parts of curing agent, and 10 parts of filler; the weight ratio of acrylic acid-modified epoxy resin, acrylic acid ester oligomer and aliphatic epoxy resin in the vinyl composition is 7:8:5;

The preparation method of the sealant composition is the same as that of Example 1.

Example 8 is basically the same as Example 1, except for the mass ratio of each component in the vinyl composition.

The raw material components of the sealant composition and their weight parts are as follows:

40 parts of bisphenol A epoxy resin, 45 parts of vinyl composition, 1.0 parts of photoinitiator, 1.5 parts of coupling agent, 2.5 parts of curing agent, and 10 parts of filler; the weight ratio of acrylic acid-modified epoxy resin, acrylic acid ester oligomer and aliphatic epoxy resin in the vinyl composition is 4:12:4;

The preparation method of the sealant composition is the same as that of Example 1.

Example 9 is basically the same as Example 1, except for the mass ratio of each component in the vinyl composition.

The raw material components of the sealant composition and their weight parts are as follows:

40 parts of bisphenol A epoxy resin, 45 parts of vinyl composition, 1.0 parts of photoinitiator, 1.5 parts of coupling agent, 2.5 parts of curing agent, and 10 parts of filler; the weight ratio of acrylic acid-modified epoxy resin, acrylic acid ester oligomer and aliphatic epoxy resin in the vinyl composition is 6:6:8;

The preparation method of the sealant composition is the same as that of Example 1.

Example 10 is basically the same as Example 1, except for the mass ratio of each component in the vinyl composition.

The raw material components of the sealant composition and their weight parts are as follows:

40 parts of bisphenol A epoxy resin, 45 parts of vinyl composition, 1.0 parts of photoinitiator, 1.5 parts of coupling agent, 2.5 parts of curing agent, and 10 parts of filler; the weight ratio of acrylic acid-modified epoxy resin, acrylic acid ester oligomer and aliphatic epoxy resin in the vinyl composition is 8:10:2;

The preparation method of the sealant composition is the same as that of Example 1.

Comparative Example 1 is basically the same as Example 1, except for the weight parts of bisphenol A epoxy resin and vinyl composition.

The raw material components of the sealant composition and their weight parts are as follows:

40 parts of bisphenol A epoxy resin, 65 parts of vinyl composition, 1.0 parts of photoinitiator, 1.5 parts of coupling agent, 2.5 parts of curing agent, and 10 parts of filler; the weight ratio of acrylic acid-modified epoxy resin, acrylic acid ester oligomer and aliphatic epoxy resin in the vinyl composition is 7:8:5;

The preparation method of the sealant composition is the same as that of Example 1.

Comparative Example 2 is basically the same as Example 1, except that the amount of acrylic modified epoxy resin in the vinyl composition is reduced.

The raw material components of the sealant composition and their weight parts are as follows:

40 parts of bisphenol A epoxy resin, 33.75 parts of vinyl composition, 1.0 parts of photoinitiator, 1.5 parts of coupling agent, 2.5 parts of curing agent, and 10 parts of filler; the weight ratio of acrylic acid-modified epoxy resin, acrylic acid ester oligomer and aliphatic epoxy resin in the vinyl composition is 2:8:5;

The preparation method of the sealant composition is the same as that of Example 1.

Comparative Example 3 is basically the same as Example 1, except that there is no acrylic oligomer in the components of the vinyl composition.

The raw material components of the sealant composition and their weight parts are as follows:

40 parts of bisphenol A epoxy resin, 27 parts of vinyl composition, 1.0 parts of photoinitiator, 1.5 parts of coupling agent, 2.5 parts of curing agent, and 10 parts of filler; the weight ratio of acrylic modified epoxy resin and aliphatic epoxy resin in the vinyl composition is 7:5;

The preparation method of the sealant composition is the same as that of Example 1.

Comparative Example 4 is basically the same as Example 1, except that the components of the vinyl composition do not contain an acrylic modified epoxy resin.

The raw material components of the sealant composition and their weight parts are as follows:

40 parts of bisphenol A epoxy resin, 29.25 parts of vinyl composition, 1.0 parts of photoinitiator, 1.5 parts of coupling agent, 2.5 parts of curing agent, and 10 parts of filler; the weight ratio of acrylate oligomer and aliphatic epoxy resin in the vinyl composition is 8:5;

The preparation method of the sealant composition is the same as that of Example 1.

Comparative Example 5 is basically the same as Example 1, except that the vinyl composition is replaced by acrylic resin.

The raw material components of the sealant composition and their weight parts are as follows:

40 parts of bisphenol A epoxy resin, 45 parts of acrylic resin, 1.0 parts of photoinitiator, 1.5 parts of coupling agent, 2.5 parts of curing agent, and 10 parts of filler;

The preparation method of the sealant composition is the same as that of Example 1.

Comparative Example 6 is basically the same as Example 1, except that the acrylic ester oligomer in the vinyl composition is replaced by acrylic resin.

The raw material components of the sealant composition and their weight parts are as follows:

40 parts of bisphenol A epoxy resin, 45 parts of vinyl composition, 1.0 parts of photoinitiator, 1.5 parts of coupling agent, 2.5 parts of curing agent, 10 parts of filler, the weight ratio of acrylic modified epoxy resin, acrylic resin and aliphatic epoxy resin in the vinyl composition is 7:8:5;

The preparation method of the sealant composition is the same as that of Example 1.

Test Case

The sealant compositions of Examples 1-10 and Comparative Examples 1-6 were subjected to performance tests, and the evaluation method was as follows:

(1) Adhesion: Place tiny drops of the sealant composition on one of two 30×40 mm glass sheets with an ITO film and a polyimide (PI) film, and attach the other glass test piece on top of the glass sheet in a cross-like arrangement, pressing to completely adhere. Irradiate with a metal halide UV lamp of 3000 mJ/ ^cm2 , and then heat at 120°C for 60 minutes to obtain an adhesive test piece. The clamps provided above and below the adhesive test piece are subjected to a tensile test (2 mm/sec). The value obtained by dividing the measured value (N) by the seal coating cross-sectional area ( ^mm2 ) is the adhesion of the sealant composition.

(2) Moisture permeability: The sealant composition was coated with a coating machine to a thickness of 200-300 μm to form a smooth release film, and then irradiated with 100 mW/ ^cm2 ultraviolet rays (wavelength 365 nm) using a metal halide lamp for 30 seconds, and then heated at 120°C to obtain a cured film for moisture permeability measurement. A moisture permeability test cup was prepared by the method of the moisture permeability test method (cup method) for moisture-proof packaging materials in JIS Z 0208, and the obtained cured film for moisture permeability measurement was installed and placed in a constant temperature and humidity oven at a temperature of 60°C and a humidity of 90%, and the moisture permeability was measured for 24 hours.

The test results are shown in Table 1 below:

Table 1

As can be seen from Table 1, the adhesive force of the sealant composition of the embodiment in ITO glass is above 4.5MPa, the adhesive force in PI glass is above 4.6MPa, and the moisture permeability of the cured film formed in the liquid crystal display element is below 53.6%. It can be seen that the sealant composition of the embodiment has excellent adhesive force and moisture permeability after curing, and is suitable for liquid crystal display products. This is because the vinyl composition used in the embodiment contains both soft segments and rigid groups. The soft segments enhance the toughness and adhesion of the resin after curing, and the rigid groups make the resin excellent in high temperature and high humidity resistance after curing. In addition, to balance the two, it is also necessary that the components in the vinyl composition are within a certain appropriate ratio.

Analysis of Examples 5-7 and Example 1 shows that the performance of Examples 5-7 is slightly worse than that of Example 1, proving that the proportion of the difunctional epoxy resin and the vinyl composition in the formula has a greater impact on the performance of the sealant composition.

Analysis of Examples 8-10 and Example 1 shows that the performance of Examples 8-10 is slightly worse than that of Example 1, proving that the mass ratio of acrylic modified epoxy resin, acrylic ester oligomer and aliphatic epoxy resin in the vinyl composition has a greater influence on the performance of the sealant composition.

Analysis of Comparative Example 1 and Example 1 shows that the performance of Comparative Example 1 is not as good as that of Example 1, which proves that the sealant composition formed by the difunctional epoxy resin and the vinyl composition within the dosage range of the example has better performance.

Analysis of Comparative Examples 2-4 and Example 1 shows that the performance of Comparative Examples 2-4 is not as good as that of Example 1, which proves that the sealant composition formed by the specific ratio range of the vinyl composition in the example has better performance.

Analysis of Comparative Example 5 and Example 1 shows that the performance of Comparative Example 5 is not as good as that of Example 1, which proves that the sealant composition formed by using the vinyl composition to replace the conventional acrylic resin oligomer has better performance.

Analysis of Comparative Example 6 and Example 1 shows that the performance of Comparative Example 6 is not as good as that of Example 1, which indicates that the types of three resins used in the vinyl composition are critical, and the effect of using the vinyl composition of the example is better than that of using other resins.

Obviously, the above embodiments are merely examples for clear explanation and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived from these are still within the protection scope of the invention.

Claims (9)

1. A sealant composition, characterized in that, in parts by mass, it comprises 5-40 parts of a bifunctional epoxy resin, 20-60 parts of a vinyl composition, 0.1-3 parts of a photoinitiator, 0.1-3 parts of a coupling agent, 0.1-5 parts of a curing agent and 1-15 parts of a filler; the vinyl composition comprises an acrylic acid-modified epoxy resin, an acrylate oligomer and an aliphatic epoxy resin; the mass ratio of the acrylic acid-modified epoxy resin, the acrylate oligomer and the aliphatic epoxy resin is (4-8):(4-12):(2-10); the structures of the acrylic acid-modified epoxy resin, the acrylate oligomer and the aliphatic epoxy resin are shown in Formula I, Formula II and Formula III, respectively: Wherein, m and n are independently integers of 1-4; X, Y, and Z are independently selected from hydrogen or methyl; R is selected from hydrogen or C1-C7 alkyl, and p and q are independently integers of 2-20. 2. The sealant composition according to claim 1, characterized in that the preparation of the acrylic acid-modified epoxy resin specifically comprises the following steps: dissolving a first antioxidant and a first polymerization inhibitor in a first solvent, heating to 80°C-100°C, and continuously adding an epoxy resin of formula IV, acrylic acid and a first catalyst to react at 120°C-150°C for 3h-8h to obtain the acrylic acid-modified epoxy resin; the structure of the epoxy resin is shown in formula IV: Here, m is an integer from 1 to 4. 3. The sealant composition according to claim 2, characterized in that the first antioxidant is 2,6-di-tert-butyl-p-cresol; The first inhibitor is p-hydroxyanisole; The first catalyst is selected from triphenylphosphine and/or tetrabutylphosphine chloride; The first solvent is selected from diethylene glycol monoethyl ether acetate and/or dipropylene glycol monomethyl ether. 4. The sealant composition according to claim 1, characterized in that the preparation of the acrylate oligomer specifically comprises the following steps: dropwise adding an acrylate monomer solution and an initiator solution into a second solvent at 100° C.-120° C. for reaction, then cooling to 70° C.-100° C., and continuously adding a second antioxidant, a second polymerization inhibitor, a second catalyst and an aliphatic epoxy resin of formula III for reaction at 100° C.-130° C. for 6 h-12 h to obtain the acrylate oligomer; the acrylate monomer comprises a first monomer and a second monomer; the first monomer is selected from methacrylic acid and/or acrylic acid; the structure of the second monomer is as shown in formula V: Wherein, X is selected from hydrogen or methyl; R is selected from hydrogen or C1-C7 alkyl. 5. The sealant composition according to claim 4, wherein the second antioxidant is 2,6-di-tert-butyl-p-cresol; The second polymerization inhibitor is p-hydroxyanisole; The second catalyst is selected from triphenylphosphine and/or tetrabutylphosphine chloride; The second solvent is selected from diethylene glycol monoethyl ether acetate and/or dipropylene glycol monomethyl ether. The sealant composition according to claim 4 , wherein the initiator is dibenzoyl peroxide. 7. The sealant composition according to claim 1, characterized in that the bifunctional epoxy resin is selected from one or more of bisphenol A epoxy resin, bisphenol F epoxy resin and bisphenol S epoxy resin; The photoinitiator is selected from one or more of diphenyl-2,4,6-trimethylbenzoylphosphine oxide, bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide, 2-benzyl-2-(dimethylamino)-1-[4-(4-morpholinyl)phenyl]-1-butanone, benzoin isopropyl ether, 2-hydroxy-2-methyl-1-phenylpropane-1-one, 2-hydroxy-2-methyl-1-phenylacetone, 2,2-dimethoxy-2-phenylacetophenone, 2-ethylanthraquinone, 2-dichlorobenzophenone, p-dimethylaminobenzoate and benzyl dimethyl ketal; The coupling agent is selected from one or more of γ-glycidoxypropyltrimethoxysilane, γ-aminopropyltriethoxysilane, γ-methacryloxypropyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, vinyltrimethoxysilane and N-β-aminoethyl-γ-aminopropyltrimethoxysilane; The curing agent is selected from one or more of organic acid hydrazides, amine compounds and acid anhydrides; The filler is selected from one or more of diatomaceous earth, silicon dioxide, calcium carbonate and talc. 8. The method for preparing the sealant composition according to any one of claims 1 to 7, characterized in that it comprises the following steps: uniformly mixing a bifunctional epoxy resin, a vinyl composition, a photoinitiator, a coupling agent, a curing agent and a filler to obtain the sealant composition. 9. Use of the sealant composition according to any one of claims 1 to 7 in a liquid crystal display element.