Matt base glue for organic silicon leather coating and preparation method of matte base glue

Abstract

The invention relates to the field of leather coating materials, and particularly discloses matte base glue for an organic silicon leather coating and a preparation method of the matte base glue. The matte base adhesive for the organic silicon leather coating is prepared from the following raw materials in parts by weight: 30-40 parts of vinyl silicone oil, 15-25 parts of pretreated silicon dioxide and 10-20 parts of vinyl MQ silicon resin, the pretreated silicon dioxide is prepared from silicon dioxide, an ethanol water solution, a silane coupling agent, a vinyl polydimethylsiloxane / polymethylsiloxane silsesquioxane cross-linked polymer, a hydroxyl-terminated polymethylvinyl siloxane-polydimethylsiloxane copolymer and a glycidyl ether substance. The prepared matte base adhesive is applied to an organic silicon leather coating and has good matte texture and flexibility, and the prepared organic silicon leather coating can keep good wear-resistant stability and is not prone to cracking after being used for a long time and can be widely applied to the fields of automobile seats, home furnishing, medical treatment and the like.

Description

Technical Field

[0001] The present application relates to the field of leather coating materials, and more specifically, it relates to a matte base glue for silicone leather coating and a preparation method thereof. Background Art

[0002] Compared with PVC artificial leather and PU leather, silicone leather has excellent leather texture, softness and environmental friendliness, and is widely used in automotive products such as car seats; home decoration products such as furniture sofas; 3C electronic products such as computers and mobile phone cases; medical and other fields. Silicone leather generally consists of a base cloth layer, an adhesive layer and a silicone leather coating. Among them, the silicone leather coating endows silicone leather with excellent texture, softness, stain resistance and wear resistance. The silicone leather coating is generally prepared by hydrosilylation reaction of vinyl silicone oil, hydrogen-containing silicone oil, platinum catalyst and additives. In order to endow the silicone leather coating with excellent properties, it is necessary to repeatedly adjust the ratio of each silicone component and additive, resulting in a relatively high cost for the entire experimental process.

[0003] In order to solve the above technical problems, formulating the raw materials of the silicone leather coating into a base glue first and then applying the base glue to the downstream formula can directly be used with reaction additives without repeatedly adjusting the components of the entire formula, which can save the downstream R & D cost and time. Therefore, the performance requirements for the base glue are relatively strict.

[0004] The base glue in the prior art generally consists of vinyl silicone oil and filler. Although it can endow the base glue with certain texture and wear resistance, when it is applied to the silicone leather coating material, the silicone leather prepared is easily affected by environmental factors after being used for a period of time, and the leather surface is still prone to wear and cracking problems. Therefore, it is necessary to further improve the performance of the base glue. Summary of the Invention

[0005] In order to solve the problems that the silicone leather prepared by applying the existing base glue to the silicone leather coating is prone to wear and cracking during long-term use, the present application provides a matte base glue for silicone leather coating and a preparation method thereof.

[0006] In the first aspect, the present application provides a matte base glue for silicone leather coating, adopting the following technical solution: A matte base glue for silicone leather coating is prepared from the following raw materials in parts by weight: Vinyl silicone oil 30 - 40 parts Pretreated silica 15 - 25 parts Vinyl MQ silicone resin 10 - 20 parts; The pretreated silica is prepared from silica, aqueous ethanol solution, silane coupling agent, vinyl polydimethylsiloxane / polymethylsiloxane silsesquioxane cross-linked polymer, hydroxyl-terminated poly(methylvinylsiloxane-dimethylsiloxane) copolymer, and glycidyl ether substances.

[0007] By adopting the above technical solution, the matte base glue of the present application is prepared from vinyl silicone oil, pretreated silica, and vinyl MQ silicone resin. The vinyl silicone oil serves as the matrix and is compounded with the vinyl MQ silicone resin to form a stable network structure, significantly improving the flexibility and wear resistance of the matte base glue. The silica is modified with aqueous ethanol solution, silane coupling agent, vinyl polydimethylsiloxane / polymethylsiloxane silsesquioxane cross-linked polymer, hydroxyl-terminated poly(methylvinylsiloxane-dimethylsiloxane) copolymer, and glycidyl ether substances to prepare pretreated silica with good dispersion uniformity. By adding the pretreated silica, the performance of the formed network molecular structure can be strengthened, further improving the matte texture and flexibility of the prepared matte base glue. When applied, it can be directly used in combination with reaction aids such as hydrogen-containing silicone oil and platinum catalyst to form a stable and dense network cross-linked macromolecular structure, thereby endowing the prepared silicone leather coating with excellent matte texture, flexibility, and wear stability, and it is not easy to crack after long-term use. It can be widely applied in fields such as car seats, home furnishings, and medical treatment.

[0008] Preferably, the pretreated silica is prepared from the following raw materials in parts by weight: Silica 100 - 120 parts 50 - 85wt% aqueous ethanol solution 60 - 100 parts Silane coupling agent 3 - 5 parts Vinyl polydimethylsiloxane / polymethylsiloxane silsesquioxane cross-linked polymer 20 - 30 parts Hydroxyl-terminated poly(methylvinylsiloxane-dimethylsiloxane) copolymer 15 - 25 parts Glycidyl ether substances 10 - 20 parts.

[0009] By adopting the above technical solution, the surface of silica is hydroxylated with an aqueous ethanol solution, and then a silane coupling agent, a vinyl polydimethylsiloxane / polymethylsiloxanesilsesquioxane cross-linked polymer, a hydroxyl-terminated poly(methylvinylsiloxane)-polydimethylsiloxane copolymer, and a glycidyl ether substance are added to modify the surface-hydroxylated silica. The vinyl polydimethylsiloxane / polymethylsiloxanesilsesquioxane cross-linked polymer can produce a good synergistic effect with silica, enhancing the matte texture and wear resistance of the prepared matte base gum. The silane coupling agent, the hydroxyl-terminated poly(methylvinylsiloxane)-polydimethylsiloxane copolymer, and the glycidyl ether substance can further cooperate and uniformly adsorb on the surfaces of silica and the vinyl polydimethylsiloxane / polymethylsiloxanesilsesquioxane cross-linked polymer, further improving the dispersion uniformity of silica and the vinyl polydimethylsiloxane / polymethylsiloxanesilsesquioxane cross-linked polymer, and thereby endowing the prepared matte base gum with better flexibility and wear stability. When the prepared matte base gum is applied, the pretreated silica can further cooperate with the matte base gum system and the reaction assistant to produce good cross-linking performance, enhancing the cross-linking density of the prepared silicone leather coating, and thereby enhancing the wear stability and anti-cracking performance of the prepared silicone leather coating.

[0010] Preferably, the silane coupling agent is composed of a γ-mercaptopropyltrimethoxysilane coupling agent and a dodecyltrimethoxysilane with a weight ratio of 1:(2 - 3).

[0011] By adopting the above technical solution, using the γ-mercaptopropyltrimethoxysilane coupling agent and the dodecyltrimethoxysilane with a relatively optimal weight ratio as the silane coupling agent can further improve the compatibility and dispersion uniformity of silica and the vinyl polydimethylsiloxane / polymethylsiloxanesilsesquioxane cross-linked polymer in the hydroxyl-terminated poly(methylvinylsiloxane)-polydimethylsiloxane copolymer and the glycidyl ether substance, thereby enhancing the modification efficiency of the pretreated silicone, and further improving the overall flexibility and tear resistance of the prepared matte base gum, making the prepared silicone leather coating less prone to wear and cracking problems during long-term use.

[0012] Preferably, the glycidyl ether substance is composed of 1,2-cyclohexanediol diglycidyl ether and 4-vinylphenyl glycidyl ether with a weight ratio of (1.5 - 2.5):1.

[0013] By adopting the above technical solution, after 1,2-cyclohexanediol diglycidyl ether and 4-vinylphenyl glycidyl ether are compounded in a specific ratio, the dispersion performance of the pretreated silica is improved, thereby enhancing the overall flexibility and wear resistance of the matte base gum, and further reducing the wear and cracking problems that are prone to occur in the silicone leather coating during long-term use.

[0014] Preferably, the particle size of the silica is 50 - 100 nm.

[0015] By adopting the above technical solution, the silica with a relatively optimal particle size can endow the silicone leather coating with a delicate matte texture, can be better dispersed in the matte base glue, and enhance the mechanical strength and wear resistance of the prepared silicone leather coating.

[0016] Preferably, the pretreated silica is prepared by the following steps: A1. Add the silica into an ethanol aqueous solution, mix and stir, and filter to obtain hydroxylated silica; A2. Add the hydroxylated silica, silane coupling agent, vinyl polydimethylsiloxane / polymethylsiloxane silsesquioxane cross-linked polymer, hydroxyl-terminated poly(methylvinylsiloxane)-polydimethylsiloxane copolymer, and glycidyl ether substance into a reaction device for kneading and dispersion to obtain pretreated silica.

[0017] By adopting the above technical solution, pretreated silica with good dispersion uniformity and compatibility is prepared.

[0018] Preferably, the vinyl content of the vinyl silicone oil is 0.9 - 1.2%, and the viscosity is 60 - 100 cst.

[0019] By adopting the above technical solution, the vinyl silicone oil with a relatively optimal vinyl content and viscosity can effectively improve the mechanical strength and fluidity of the matte base glue, so that when used in combination with the pretreated silica and vinyl MQ silicone resin, the wear resistance and anti-cracking performance of the silicone leather are enhanced, and at the same time, good processing performance and soft leather texture are ensured.

[0020] Preferably, the vinyl content of the vinyl MQ silicone resin is 1.2 - 1.5%, the viscosity is 80 - 200 cst, and the MQ ratio is 0.8 - 0.9.

[0021] By adopting the above technical solution, the specific vinyl content, viscosity, and MQ ratio of the vinyl MQ silicone resin have a moderate network cross-linked structure, which can significantly improve the overall stability and mechanical strength of the matte base glue, thereby effectively enhancing the wear resistance and durability of the prepared silicone leather coating, and reducing the wear and cracking phenomena caused by environmental factors during long-term use.

[0022] In the second aspect, the present application provides a preparation method for a matte base glue for a silicone leather coating, adopting the following technical solution: A preparation method for a matte base glue for a silicone leather coating, comprising the following steps: adding vinyl silicone oil, pretreated silica, and vinyl MQ silicone resin into a reaction device for kneading to obtain a matte base glue for a silicone leather coating.

[0023] By adopting the above technical solution, the prepared matte base glue has good wear resistance and anti-cracking performance when applied to the silicone leather coating, and the service life of the silicone leather coating is prolonged.

[0024] Preferably, the kneading temperature is 55 - 75 °C and the kneading time is 1 - 3 h.

[0025] By adopting the above technical solution, the preferable kneading temperature and time can effectively promote the uniform dispersion performance among vinyl silicone oil, pretreated silica, and vinyl MQ silicone resin, and improve the stability and mechanical properties of the matte base glue.

[0026] In summary, this application includes at least one of the following beneficial technical effects: 1. In this application, vinyl silicone oil, pretreated silica, and vinyl MQ silicone resin are compounded to prepare a matte base glue. The prepared matte base glue has good matte texture, wear resistance, and flexibility. When applied to the silicone leather coating, it solves the problems of easy wear and cracking of the silicone leather coating during long-term use, and can be widely applied to fields such as car seats, home furnishing, and medical treatment. 2. By using an ethanol aqueous solution to perform surface hydroxylation treatment on silica, and then adding a silane coupling agent, vinyl polydimethylsiloxane / polymethylsiloxane silsesquioxane cross-linked polymer, hydroxyl-terminated poly(methylvinylsiloxane)-polydimethylsiloxane copolymer, and glycidyl ether substances to modify the surface-hydroxylated silica, the prepared pretreated silica can cooperate with the matte base glue system during application, further cross-link with reaction assistants, and further improve the matte texture, flexibility, and wear resistance of the prepared matte base glue.

[0027] 3. Using γ-mercaptopropyltrimethoxysilane coupling agent and dodecyltrimethoxysilane as silane coupling agents, and 1,2-cyclohexanediol diglycidyl ether and 4-vinylphenyl glycidyl ether as glycidyl ether substances can further improve the dispersion uniformity of the prepared pretreated silica, and further improve the flexibility and wear stability of the prepared matte base glue. Specific Embodiments

[0028] The following further elaborates on this application with reference to embodiments.

[0029] The following are the sources and specifications of some raw materials of this application. The raw materials used in the preparation examples and embodiments of this application can all be obtained commercially, including but not limited to the raw materials of the following models and manufacturers. Raw materials with the same performance can all be used: 1. Silica: Fumed silica, with a particle size of 50 - 100 nm; 2. Vinyl silicone oil: The vinyl content is 0.9 - 1.2%, and the viscosity is 60 - 100 cst; 3. Vinyl MQ silicone resin: The vinyl content is 1.2 - 1.5%, the viscosity is 80 - 200 cst, and the MQ ratio is 0.8 - 0.9; 4. Vinyl polydimethylsiloxane / polymethylsiloxane silsesquioxane cross-linked polymer: Model KSP101; 5. Hydroxyl-terminated poly(methylvinylsiloxane)-polydimethylsiloxane copolymer: OF6051, Sisebo Silicone.

[0030] Preparation example of pretreated silica Preparation example 1 Preparation example 1 discloses a pretreated silica, which is prepared by the following steps: A1. Add 10 kg of silica to 6 kg of 50 wt% ethanol aqueous solution, heat up to 50 °C, mix and stir for 60 min, and filter to obtain hydroxylated silica; A2. Add the hydroxylated silica obtained in step A1, 0.3 kg of silane coupling agent (composed of vinyltrimethoxysilane and dodecyltrimethoxysilane with a weight ratio of 1:2), 3 kg of vinyl polydimethylsiloxane / polymethylsiloxane silsesquioxane cross-linked polymer, 1.5 kg of hydroxyl-terminated poly(methylvinylsiloxane)-polydimethylsiloxane copolymer, and 2 kg of glycidyl ether substances (composed of ethylene glycol diglycidyl ether and 1,2-cyclohexanediol diglycidyl ether with a weight ratio of 1:1) into the reaction kettle, and carry out kneading and dispersion at a temperature of 70 °C for 2 h to obtain pretreated silica.

[0031] Preparation examples 2 - 3 The differences between preparation examples 2 - 3 and preparation example 1 are that the preparation parameters are different. For details, see Table 1 below.

[0032] Table 1 Preparation parameter table of preparation examples 1 - 3 Preparation example 4 The difference between preparation example 4 and preparation example 1 is that the silane coupling agent is composed of γ-mercaptopropyltrimethoxysilane coupling and dodecyltrimethoxysilane with a weight ratio of 1:2, and the others are the same as preparation example 1.

[0033] Preparation example 5 The difference between preparation example 5 and preparation example 1 is that the silane coupling agent is composed of γ-mercaptopropyltrimethoxysilane coupling and dodecyltrimethoxysilane with a weight ratio of 1:3, and the others are the same as preparation example 1.

[0034] Preparation Example 6 The difference between Preparation Example 6 and Preparation Example 4 is that the glycidyl ether substances are composed of 1,2 - cyclohexanediol diglycidyl ether and 4 - vinylphenyl glycidyl ether with a weight ratio of 1.5:1, and the others are the same as Preparation Example 4.

[0035] Preparation Example 7 The difference between Preparation Example 7 and Preparation Example 4 is that the glycidyl ether substances are composed of 1,2 - cyclohexanediol diglycidyl ether and 4 - vinylphenyl glycidyl ether with a weight ratio of 2.5:1, and the others are the same as Preparation Example 4.

[0036] Preparation Comparative Example 1 The difference between Preparation Comparative Example 1 and Preparation Example 1 is that the vinyl polydimethylsiloxane / polymethylsilsesquioxane cross - linked polymer is replaced with silica in equal amount, and the others are the same as Preparation Example 1.

[0037] Preparation Comparative Example 2 The difference between Preparation Comparative Example 2 and Preparation Example 1 is that the hydroxy - terminated poly(methylvinylsiloxane - dimethylsiloxane) copolymer is replaced with hydroxy - terminated polydimethylsiloxane in equal amount, OF0025, Sibo Organosilicon, and the others are the same as Preparation Example 1.

[0038] Preparation Comparative Example 3 The difference between Preparation Comparative Example 3 and Preparation Example 1 is that the glycidyl ether substances are replaced with silane coupling agents in equal amount, and the others are the same as Preparation Example 1.

[0039] Preparation Comparative Example 4 The difference between Preparation Comparative Example 4 and Preparation Example 1 is that the glycidyl ether substances are replaced with polyethylene glycol 800 in equal amount, and the others are the same as Preparation Example 1. Examples

[0040] Example 1 Example 1 discloses a matte base glue for organosilicon leather coating, which is prepared by the following steps: adding 3 kg of vinyl silicone oil, 1.5 kg of pretreated silica prepared in Preparation Example 1, and 2 kg of vinyl MQ silicone resin into a mixer for kneading. The kneading temperature is 55 °C and the kneading time is 3 h to obtain the matte base glue for organosilicon leather coating.

[0041] Examples 2 - 3 The difference between Examples 2 - 3 and Example 1 is that the raw material dosages and preparation parameters are different. See Table 2 below for details.

[0042] Table 2 Parameter Table of Examples 1 - 3 Examples 4 - 7 The differences between Examples 4 - 7 and Example 1 lie in the different sources of the pretreated silica. See Table 3 below for details.

[0043] Table 3 Sources of Pretreated Silica in Examples 4 - 7 Example Source of pretreated silica Example 4 Preparation Example 4 Example 5 Preparation Example 5 Example 6 Preparation Example 6 Example 7 Preparation Example 7 Comparative Examples Comparative Examples 1 - 4 The differences between Comparative Examples 1 - 4 and Example 1 lie in the different sources of the pretreated silica. See Table 4 below for details.

[0044] Table 4 Sources of Pretreated Silica in Comparative Examples 1 - 4 Comparative Example Source of pretreated silica Comparative Example 1 Preparation of Comparative Example 1 Comparative Example 2 Preparation of Comparative Example 2 Comparative Example 3 Preparation of Comparative Example 3 Comparative Example 4 Preparation of Comparative Example 4 Comparative Example 5 The difference between Comparative Example 5 and Example 1 is that the pretreated silica is replaced with an equal amount of fumed silica, and the others are the same as in Example 1.

[0045] Application Examples Application Example 1 Application Example 1 discloses an organosilicon leather coating material, which is prepared by the following steps: adding 10 kg of the matte base glue of Example 1, 0.8 kg of hydrogen-containing silicone oil, 0.2 kg of platinum catalyst, and 0.02 kg of 1-ethynylcyclohexanol as an inhibitor into a mixer, and mixing evenly to obtain the organosilicon leather coating material; the hydrogen-containing silicone oil is an end-hydrogen-containing silicone oil with the model HF2030 - M134, with a hydrogen content of 1.5%, and the platinum content in the platinum catalyst is 5000 ppm.

[0046] Application Examples 2 - 12 The differences between Application Examples 2 - 12 and Application Example 1 lie in the different sources of the matte base glue. See Table 5 below for details.

[0047] Table 5 Sources of Matte Base Glue in Application Examples 1 - 12 Application Example Source table of matte base glue Application Example 1 Example 1 Application Example 2 Example 2 Application Example 3 Example 3 Application Example 4 Example 4 Application Example 5 Example 5 Application Example 6 Example 6 Application Example 7 Example 7 Application Example 8 Comparative Example 1 Application Example 9 Comparative Example 2 Application Example 10 Comparative Example 3 Application Example 11 Comparative Example 4 Application Example 12 Comparative Example 5 Performance Detection Test The following performance tests were carried out on the organosilicon leather coating materials prepared in Application Examples 1 - 12: Coat an organosilicon adhesive (Kanglibang, KL - 2620) on the surface of the base fabric, and form an organosilicon layer after drying. Coat the organosilicon leather coating prepared in Application Examples 1 - 12 on the surface of the organosilicon layer, and form an organosilicon leather coating with a thickness of 10 μm after curing and drying. Thus, an organosilicon leather is prepared, and the following tests were carried out on the prepared organosilicon leather: 1. Glossiness Detection Use a glossiness tester to detect the glossiness (unit: GU) of the silicone leather. The lower the glossiness, the better the matte effect. Test and record the test results; 2. Abrasion resistance test Use a Martindale abrasion resistance tester to conduct tests at room temperature (25°C) with a load of 595 g, a speed of 50 r / min, and a stroke of 24 mm. Calculate the abrasion of the silicone leather after 30,000 tests, record the abrasion mass (unit: g). If it wears through to the bottom, record it as worn through to the bottom and do not calculate the abrasion mass. Test and record the test results; 3. Heat resistance test Place the silicone leather in a thermo-hygrostat at a temperature of 50°C and a humidity of 85% for 7 days. Calculate the abrasion of the silicone leather after 30,000 tests, record the abrasion mass (unit: g). If it wears through to the bottom, record it as worn through to the bottom and do not calculate the abrasion mass. Test and record the test results; 4. Sweat resistance test Drop neutral standard artificial sweat onto the silicone leather and add 1 drop of artificial sweat every 10,000 tests. Calculate the abrasion of the silicone leather after 30,000 tests, record the abrasion mass (unit: g). If it wears through to the bottom, record it as worn through to the bottom and do not calculate the abrasion mass. Test and record the test results.

[0048] The following are the performance test data of the silicone leather coatings in Application Examples 1 - 12. See Table 6 below for details.

[0049] Table 6 Performance test data table of the silicone leather coatings in Application Examples 1 - 12 Combining Application Examples 1 - 3 and Application Examples 4 - 5 and referring to Table 6, it can be concluded that by optimizing the types and ratios of silane coupling agents, the matte performance and wear resistance stability of the prepared matte base glue can be improved. Compared with Application Example 1, Application Examples 4 - 5 have an increased matte degree and a significantly reduced abrasion mass. This may be because γ-mercaptopropyltrimethoxysilane coupling agent and dodecyltrimethoxysilane with a better weight ratio as silane coupling agents can improve the dispersion uniformity of silica in the matte base glue system, thereby enhancing the matte texture and wear resistance stability of the prepared silicone leather coating.

[0050] Combining Application Examples 4-5 and Application Examples 6-7 and referring to Table 6, it can be concluded that by optimizing the types and proportions of glycidyl ether substances, the wear resistance stability of the prepared matte base glue can be further improved. Compared with Application Example 4, Application Examples 6-7 use 1,2-cyclohexanediol diglycidyl ether and 4-vinylphenyl glycidyl ether with a better weight ratio as glycidyl ether substances, and the wear mass is significantly reduced. This may be because the selection of better glycidyl ether substances further improves the compatibility and flexibility of pretreated silica in the matte base glue, thereby enhancing the wear resistance stability of the prepared silicone leather coating.

[0051] Combining Application Examples 1-3 and Application Examples 8-12 and referring to Table 6, it can be obtained that in Application Example 8, when the vinyl polydimethylsiloxane / polymethylsiloxane silsesquioxane cross-linked polymer is replaced with silica, the glossiness of the prepared silicone leather coating is significantly improved, but the wear resistance is also significantly reduced, and the bottoming occurs after the wear resistance test. This may be because the synergistic effect of silica and vinyl polydimethylsiloxane / polymethylsiloxane silsesquioxane cross-linked polymer is reduced. In Application Example 9, when the hydroxyl-terminated polymethylvinylsiloxane-polydimethylsiloxane copolymer is replaced with hydroxyl-terminated polydimethylsiloxane, the wear resistance stability of the prepared silicone leather coating may be due to the reduction of the cross-linking performance between pretreated silica and the base glue system and hydrogen-containing silicone oil, thereby reducing the wear resistance, and the problem of bottoming occurs after the wear resistance test. In Application Examples 10-11, the application of silane coupling agent and glycidyl ether substances is changed, and the wear resistance stability of the prepared silicone leather coating is reduced. In Application Example 12, silica is directly used for compounding, and the glossiness of the prepared silicone leather coating is not only significantly reduced, but also bottoming and cracking occur. This may be because the dispersion uniformity of silica in the base glue system is poor, resulting in uneven glossiness of the local silicone leather coating and the problems of bottoming and cracking.

[0052] This specific embodiment is only an interpretation of the present application, and it does not limit the present application. After reading this specification, those skilled in the art can make modifications without creative contributions to this embodiment as needed, but as long as it is within the scope of the claims of the present application, it is protected by the patent law.

Claims

1. A matte base adhesive for silicone leather coating, characterized in that: Made from the following raw materials in parts by weight: 30-40 parts of vinyl silicone oil Pre-treated silica 15-25 parts 10-20 parts of vinyl MQ silicone resin; The pretreated silicon dioxide is prepared from silicon dioxide, ethanol aqueous solution, silane coupling agent, vinyl polydimethylsiloxane / polymethylsiloxane silsesquioxane crosslinked polymer, hydroxyl-terminated polymethylvinylsiloxane-polydimethylsiloxane copolymer and glycidyl ether substances.

2. The matte base adhesive for silicone leather coating according to claim 1, characterized in that: The pretreated silicon dioxide is prepared from the following raw materials in parts by weight: Silicon dioxide 100-120 parts 60-100 parts of 50-85wt% ethanol aqueous solution Silane coupling agent 3-5 parts Vinyl Dimethicone / Methicone Silsesquioxane Crosspolymer 20-30 parts 15-25 parts of hydroxyl-terminated polymethylvinylsiloxane-polydimethylsiloxane copolymer 10-20 parts of glycidyl ether substances.

3. The matte base adhesive for silicone leather coating according to claim 2, characterized in that: The silane coupling agent is composed of a γ-mercaptopropyltrimethoxysilane coupling agent and dodecyltrimethoxysilane in a weight ratio of 1:(2-3).

4. The matte base adhesive for silicone leather coating according to claim 2, characterized in that: The glycidyl ether substance consists of 1,2-cyclohexanediol diglycidyl ether and 4-vinylphenyl glycidyl ether in a weight ratio of (1.5-2.5):

1.

5. The matte base adhesive for silicone leather coating according to claim 1, characterized in that: The particle size of the silicon dioxide is 50-100 nm.

6. A matte base adhesive for silicone leather coating according to any one of claims 1 to 5, characterized in that: The pretreated silicon dioxide is prepared by the following steps: A1. Adding silicon dioxide to an ethanol aqueous solution, mixing and stirring, and filtering to obtain hydroxylated silicon dioxide; A2. Add hydroxylated silica, silane coupling agent, vinyl polydimethylsiloxane / polymethylsiloxane silsesquioxane crosslinked polymer, hydroxyl-terminated polymethylvinylsiloxane-polydimethylsiloxane copolymer and glycidyl ether substances into a reaction device for kneading and dispersion to obtain pretreated silica.

7. The matte base adhesive for silicone leather coating according to claim 1, characterized in that: The vinyl content of the vinyl silicone oil is 0.9-1.2% and the viscosity is 60-100 cst.

8. The matte base adhesive for silicone leather coating according to claim 1, characterized in that: The vinyl MQ silicone resin has a vinyl content of 1.2-1.5%, a viscosity of 80-200 cst, and an MQ ratio of 0.8-0.

9.

9. A method for preparing a matte base adhesive for silicone leather coating according to any one of claims 1 to 8, characterized in that: The following steps are involved: Vinyl silicone oil, pretreated silica and vinyl MQ silicone resin are added into a reaction device for kneading to prepare a matte base adhesive for silicone leather coating.

10. The method for preparing a matte base adhesive for silicone leather coating according to claim 9, characterized in that: The kneading temperature is 55-75°C, and the kneading time is 1-3h.

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