Water vapor permeable organic silicone synthetic leather and preparation method thereof

Abstract

The present application relates to machine silicon synthetic leather technical field, disclose a kind of water vapor permeable organic silicon synthetic leather and its preparation method.The following steps are included:(1) the surface glue with the thickness of 10~50 μm is coated on release paper, and heated and solidified in 110~140 ℃ for 1~3 min;(2) the bottom glue with the thickness of 80~200 μm is coated on the surface of the solidified surface glue, and heated and solidified in 110~140 ℃ for 1~3 min;(3) the bottom glue with the thickness of 50~100 μm is coated again on the surface of the solidified bottom glue, and the base cloth is attached, heated and solidified in 110~140 ℃ for 3~8 min, and the release paper is removed, and water vapor permeable organic silicon synthetic leather is prepared.The present application improves the affinity of silicone rubber to water, and improves the crosslinking density, and good reinforcing effect is achieved.Meanwhile, the present application introduces polyether segment into silicone rubber, which can effectively improve the affinity of silicone rubber to water, and improve the water vapor permeability of organic silicon synthetic leather.

Description

Technical Field

[0001] This invention relates to the field of silicone synthetic leather technology, specifically to a water-permeable silicone synthetic leather and its preparation method. Background Technology

[0002] my country's annual synthetic leather production exceeds 5 billion square meters, widely used in automobiles, aviation, medical, clothing, bags, furniture, decoration, and many other fields, closely related to people's daily life, work, and travel. However, traditional synthetic leather (polyvinyl chloride synthetic leather and polyurethane synthetic leather) has problems such as poor environmental performance, weather resistance, and lack of stain resistance, and cannot meet people's demand for high-performance synthetic leather.

[0003] Silicone-based synthetic leather has become a hot research area in synthetic leather in recent years. It boasts advantages such as being solvent-free and environmentally friendly, weather-resistant, stain-resistant, skin-friendly, resistant to high and low temperatures, flame-retardant, and resistant to chemical corrosion, overcoming most of the shortcomings of traditional synthetic leather. However, both silicone-based and traditional synthetic leathers need improvement in terms of water vapor permeability.

[0004] Patent CN 102041688A discloses a waterproof and breathable silicone synthetic leather and its manufacturing method. By adding a large amount of sodium chloride to the coating material, and then dissolving the sodium chloride in a large amount of water after the leather making process is completed to form pores, water vapor can be permeated. The process generates a large amount of wastewater and affects the appearance, strength and other properties of the synthetic leather. Patent CN 105544234A improves the water vapor permeability of silicone synthetic leather by using an open-cell foamed silicone coating, but this method affects the appearance, wear resistance and other properties of the synthetic leather.

[0005] The aforementioned studies have failed to prepare water-permeable silicone synthetic leather without affecting the inherent properties of silicone rubber synthetic leather. Therefore, it is necessary to develop a water-permeable silicone synthetic leather and its preparation method, so that the silicone synthetic leather possesses good abrasion resistance and interlayer adhesion, while also exhibiting excellent water permeability. Summary of the Invention

[0006] The present invention aims to solve at least one of the technical problems existing in the prior art. To this end, the present invention proposes a water-permeable silicone synthetic leather and its preparation method, which enables the silicone synthetic leather to have good abrasion resistance and interlayer adhesion, while also having excellent water permeability.

[0007] The first aspect of the present invention provides a method for preparing water-permeable silicone synthetic leather.

[0008] Specifically, it includes the following steps:

[0009] (1) Coat the release paper with a thickness of 10-50 μm of adhesive and heat it at 110-140℃ for 1-3 min to cure;

[0010] (2) Apply a base coat with a thickness of 80-200 μm to the surface of the cured top coat and heat it at 110-140℃ for 1-3 min to cure it;

[0011] (3) Apply a base coat of 50-100 μm thickness to the surface of the cured base coat, attach the base fabric, heat and cure at 110-140℃ for 3-8 min, peel off the release paper, and obtain water-permeable silicone synthetic leather.

[0012] Preferably, the preparation method of the adhesive includes the following steps: by weight, 80-120 parts of vinyl-terminated silicone oil, 5-20 parts of silica, and 30-70 parts of polysilsesquioxane are mixed and vacuum stirred for 0.5-2 hours; then 5-20 parts of polyether block silicone oil, 10-30 parts of polyether-modified hydrogen-containing silicone oil, 5-20 parts of crosslinking agent, and 0.1-5 parts of inhibitor are added and vacuum stirred for 0.1-1 hours; finally, 0.2-5 parts of catalyst are added, stirred, bubbles are removed, and impurities are filtered to obtain the adhesive.

[0013] More preferably, the mixing device is a planetary mixer or a high-speed disperser.

[0014] Preferably, the preparation method of the primer includes the following steps: by weight, 80-120 parts of vinyl-terminated silicone oil, 10-35 parts of silica, and 5-40 parts of polysilsesquioxane are mixed and vacuum stirred for 0.5-2 hours; then 5-25 parts of polyether block silicone oil, 10-25 parts of polyether modified hydrogen-containing silicone oil, 5-20 parts of crosslinking agent, and 0.1-5 parts of inhibitor are added and vacuum stirred for 0.1-1 hours; finally, 0.2-5 parts of catalyst are added, stirred, bubbles are removed, and impurities are filtered to obtain the primer.

[0015] Preferably, the vinyl content of the end-vinyl silicone oil is 0.06 to 0.2 wt% and the viscosity is 5000 to 100000 mPa·s.

[0016] Preferably, the polysilsesquioxane has the structural formula shown in Formula I:

[0017]

[0018] Where m is an integer from 2 to 30; R is The proportion of R is 20% to 60%.

[0019] Compared with traditional reinforcing fillers, polysilsesquioxane has a smaller thickening effect, which facilitates the application of silicone in the leather making process. The R-group has two main advantages in choosing the above two structures: (1) the vinyl groups on the methacrylate groups can participate in the cross-linking reaction, increase the cross-linking density of the system, and provide a reinforcing effect; (2) the introduction of ester groups and epoxy groups helps to improve the water vapor permeability.

[0020] Preferably, the polyether block silicone oil has the structural formula shown in Formula II:

[0021]

[0022] Where a is an integer from 0 to 30; b is an integer from 1 to 10; and c is an integer from 1 to 50.

[0023] The addition of polyether block silicone oil introduces hydrophilic polyether segments into the silicone rubber backbone, which can improve the affinity of silicone rubber for water and enhance the water vapor permeability of silicone synthetic leather.

[0024] Preferably, the polyether-modified hydrogen-containing silicone oil has the structural formula shown in Formula III:

[0025]

[0026] Where d is an integer from 0 to 30; e is an integer from 5 to 30; f is an integer from 5 to 30; and n is an integer from 2 to 10.

[0027] Polyether-modified hydrogen-containing silicone oil, as a partial crosslinking agent, can also introduce hydrophilic polyether segments into silicone rubber, thereby improving the affinity of silicone rubber for water and enhancing the water vapor permeability of silicone synthetic leather.

[0028] Preferably, the crosslinking agent is a hydrogen-containing silicone oil with a viscosity of 30–200 mPa·s and a hydrogen content of 0.36%–1.2%.

[0029] Preferably, the inhibitor is at least one of polyethylenesiloxane, alkynyl alcohol, and maleate ester.

[0030] Preferably, the silica is fumed silica or precipitated silica.

[0031] Preferably, the catalyst is a platinum-vinyl complex or a platinum-alkynyl complex.

[0032] A second aspect of the present invention provides a water-permeable silicone synthetic leather.

[0033] Specifically, the water-permeable silicone synthetic leather is prepared by the preparation method described in the first aspect.

[0034] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0035] This invention uses polysilsesquioxane to reinforce silicone rubber. While it has a relatively small thickening effect on silicone rubber, the introduction of epoxypropoxy and methacryloxy groups into the side groups of the polysilsesquioxane improves the silicone rubber's affinity for water and allows the methacryloxy groups to participate in the crosslinking reaction, increasing the crosslinking density and achieving a good reinforcing effect. Simultaneously, this invention uses polyether-block silicone oil and polyether-modified hydrogen-containing silicone oil to introduce polyether segments into the silicone rubber, effectively improving its affinity for water and enhancing the water vapor permeability of the silicone synthetic leather. Detailed Implementation

[0036] To enable those skilled in the art to more clearly understand the technical solutions described in this invention, the following embodiments are provided for illustration. It should be noted that the following embodiments do not constitute a limitation on the scope of protection claimed by this invention.

[0037] Unless otherwise specified, the raw materials, reagents or devices used in the following examples are available from conventional commercial sources or can be obtained by existing known methods.

[0038] Example 1

[0039] A water-permeable silicone synthetic leather and its preparation method.

[0040] Includes the following steps:

[0041] (1) Preparation of the adhesive: By weight, 100 parts of vinyl-terminated silicone oil (20000 mPa·s), 10 parts of silica (Wacker T-30), and 50 parts of polysilsesquioxane (m=15, 45% propylene oxide) were added to a planetary mixer or high-speed disperser and stirred under vacuum for 1 hour. Then, 10 parts of polyether block silicone oil (a=10, b=5, c=20), 20 parts of polyether modified hydrogen-containing silicone oil (d=10, e=15, f=15, n=10), 10 parts of crosslinking agent (viscosity 150 mPa·s, hydrogen content 0.75%) and 0.3 parts of alkynylcyclohexanol were added and stirred under vacuum for 0.5 hours. Finally, 3 parts of platinum-vinyl complex were added, stirred, degassed, and impurities were filtered to obtain the adhesive.

[0042] (2) Preparation of primer: By weight, 100 parts of vinyl-terminated silicone oil (20000 mPa·s), 25 parts of silica (Wacker T-30), and 15 parts of polysilsesquioxane (m=15, 45% propylene oxide) were added to a planetary mixer or high-speed disperser and stirred under vacuum for 1 hour. Then, 10 parts of polyether block silicone oil (a=10, b=5, c=20), 20 parts of polyether modified hydrogen-containing silicone oil (d=10, e=15, f=15, n=10), 10 parts of crosslinking agent (viscosity 150 mPa·s, hydrogen content 0.5%) and 0.3 parts of alkynylcyclohexanol were added and stirred under vacuum for 0.5 hours. Finally, 3 parts of platinum-vinyl complex were added, stirred, degassed, and impurities were filtered to obtain primer.

[0043] (3) Coat the release paper with a surface adhesive with a thickness of 20 μm, and then bake at 130℃ for 2 min (first layer);

[0044] (4) Apply a base coat to the surface of the top coat, with a thickness of 140 μm, and then bake at 130 °C for 2 min (second layer);

[0045] (5) After curing, another layer of base adhesive is coated on the surface of the base adhesive with a thickness of 70μm (third layer). Then, the base fabric is bonded to the base adhesive and baked at 130℃ for 4min. The release paper is then peeled off to obtain water-permeable silicone synthetic leather.

[0046] Example 2

[0047] A water-permeable organosilicon synthetic leather and its preparation method.

[0048] Includes the following steps:

[0049] (1) Preparation of the adhesive: By weight, 100 parts of vinyl-terminated silicone oil (20000 mPa·s), 20 parts of silica (Wacker H2000), and 50 parts of polysilsesquioxane (m=15, propylene oxide content of 20%) were added to a planetary mixer or high-speed disperser and stirred under vacuum for 1 hour. Then, 10 parts of polyether block silicone oil (a=10, b=5, c=20), 20 parts of polyether modified hydrogen-containing silicone oil (d=10, e=15, f=15, n=5), 10 parts of crosslinking agent (viscosity 150 mPa·s, hydrogen content 0.9%) and 0.1 parts of alkynylcyclohexanol were added and stirred under vacuum for 0.5 hours. Finally, 0.2 parts of platinum-vinyl complex were added, stirred, degassed, and impurities were filtered to obtain the adhesive.

[0050] (2) Preparation of primer: By weight, 100 parts of vinyl-terminated silicone oil (5000 mPa·s), 35 parts of silica (Wacker H2000), and 5 parts of polysilsesquioxane (m=2, 45% propylene oxide) were added to a planetary mixer or high-speed disperser and stirred under vacuum for 1 hour. Then, 10 parts of polyether block silicone oil (a=10, b=5, c=20), 20 parts of polyether modified hydrogen-containing silicone oil (d=10, e=15, f=15, n=10), 5 parts of crosslinking agent (viscosity 100 mPa·s, hydrogen content 0.36%) and 0.1 parts of alkynylcyclohexanol were added and stirred under vacuum for 0.5 hours. Finally, 0.2 parts of platinum-vinyl complex were added, stirred, degassed, and impurities were filtered to obtain primer.

[0051] (3) Coat the release paper with a surface adhesive with a thickness of 50 μm, and then bake at 140 °C for 3 min (first layer);

[0052] (4) Apply a base coat to the surface of the top coat, with a thickness of 80 μm, and then bake at 140 °C for 3 min (second layer);

[0053] (5) After curing, another layer of base adhesive is coated on the surface of the base adhesive with a thickness of 100μm (third layer). Then, the base fabric is bonded to the base adhesive and baked at 140℃ for 8 minutes. The release paper is then peeled off to obtain water-permeable silicone synthetic leather.

[0054] Example 3

[0055] A water-permeable silicone synthetic leather and its preparation method.

[0056] Includes the following steps:

[0057] (1) Preparation of the adhesive: By mass, 100 parts of vinyl-terminated silicone oil (100000 mPa·s), 5 parts of silica (Wacker T40), and 70 parts of polysilsesquioxane (m=30, 60% of propylene oxide) were added to a planetary mixer or high-speed disperser and stirred under vacuum for 1 hour. Then, 5 parts of polyether block silicone oil (a=0, b=10, c=50), 30 parts of polyether modified hydrogen-containing silicone oil (d=30, e=30, f=30, n=10), 15 parts of crosslinking agent (viscosity 50 mPa·s, hydrogen content 0.75%) and 1 part of alkynylcyclohexanol were added and stirred under vacuum for 0.5 hours. Finally, 3 parts of platinum-vinyl complex were added, stirred, degassed, and impurities were filtered to obtain the adhesive.

[0058] (2) Preparation of primer: By weight, 100 parts of vinyl-terminated silicone oil (20000 mPa·s), 10 parts of silica (Wacker T-40), and 40 parts of polysilsesquioxane (m=25, 60% propylene oxide) were added to a planetary mixer or high-speed disperser and stirred under vacuum for 1 hour. Then, 10 parts of polyether block silicone oil (a=10, b=5, c=20), 20 parts of polyether modified hydrogen-containing silicone oil (d=10, e=15, f=15, n=10), 20 parts of crosslinking agent (viscosity 30 mPa·s, hydrogen content 0.75%) and 1 part of alkynylcyclohexanol were added and stirred under vacuum for 0.5 hours. Finally, 3 parts of platinum-vinyl complex were added, stirred, degassed, and impurities were filtered to obtain primer.

[0059] (3) Coat the release paper with a surface adhesive with a thickness of 10 μm, and then bake at 130°C for 2 min (first layer);

[0060] (4) Apply a base coat to the surface of the top coat, with a thickness of 200 μm, and then bake at 130°C for 2 min (second layer);

[0061] (5) After curing, another layer of base adhesive is coated on the surface of the base adhesive with a thickness of 50μm (third layer). Then, the base fabric is bonded to the base adhesive and baked at 130℃ for 4min. The release paper is then peeled off to obtain water-permeable silicone synthetic leather.

[0062] Example 4

[0063] A water-permeable organosilicon synthetic leather and its preparation method.

[0064] Includes the following steps:

[0065] (1) Preparation of the face adhesive: By mass, 100 parts of vinyl-terminated silicone oil (60000 mPa·s), 10 parts of silica (Wacker H2000), and 60 parts of polysilsesquioxane (m=10, 50% of epoxypropoxypropyl) were added to a planetary mixer or high-speed disperser and stirred under vacuum for 1 hour. Then, 20 parts of polyether block silicone oil (a=30, b=10, c=1), 10 parts of polyether modified hydrogen-containing silicone oil (d=0, e=10, f=10, n=10), 10 parts of crosslinking agent (viscosity 150 mPa·s, hydrogen content 0.75%) and 5 parts of alkynylcyclohexanol were added and stirred under vacuum for 0.5 hours. Finally, 5 parts of platinum-vinyl complex were added, stirred, degassed, and impurities were filtered to obtain the face adhesive.

[0066] (2) Preparation of primer: By weight, 100 parts of vinyl-terminated silicone oil (20000 mPa·s), 25 parts of silica (Evonik D10), and 25 parts of polysilsesquioxane (m=30, propylene oxide content of 55%) were added to a planetary mixer or high-speed disperser and stirred under vacuum for 1 hour. Then, 5 parts of polyether block silicone oil (a=0, b=1, c=50), 25 parts of polyether modified hydrogen-containing silicone oil (d=30, e=30, f=30, n=10), 5 parts of crosslinking agent (viscosity 150 mPa·s, hydrogen content 0.9%) and 5 parts of alkynylcyclohexanol were added and stirred under vacuum for 0.5 hours. Finally, 5 parts of platinum-vinyl complex were added, stirred, degassed, and impurities were filtered to obtain primer.

[0067] (3) Coat the release paper with a surface adhesive with a thickness of 20 μm, and then bake at 110 °C for 2 min (first layer);

[0068] (4) Apply a base coat to the surface of the top coat, with a thickness of 150 μm, and then bake at 110 °C for 2 min (second layer);

[0069] (5) After curing, another layer of base adhesive is coated on the surface of the base adhesive with a thickness of 60μm (third layer). Then, the base fabric is bonded to the base adhesive and baked at 110℃ for 6min. The release paper is then peeled off to obtain water-permeable silicone synthetic leather.

[0070] Example 5

[0071] A water-permeable organosilicon synthetic leather and its preparation method.

[0072] Includes the following steps:

[0073] (1) Preparation of the face adhesive: By mass, 100 parts of vinyl-terminated silicone oil (40000 mPa·s), 15 parts of silica (Wacker H2000), and 40 parts of polysilsesquioxane (m=10, 50% of epoxypropoxypropyl) were added to a planetary mixer or high-speed disperser and stirred under vacuum for 1 hour. Then, 20 parts of polyether block silicone oil (a=30, b=10, c=1), 20 parts of polyether modified hydrogen-containing silicone oil (d=0, e=10, f=10, n=10), 10 parts of crosslinking agent (viscosity 30 mPa·s, hydrogen content 1.2%) and 2 parts of alkynylcyclohexanol were added and stirred under vacuum for 0.5 hours. Finally, 4 parts of platinum-vinyl complex were added, stirred, degassed, and impurities were filtered to obtain the face adhesive.

[0074] (2) Preparation of primer: By weight, 100 parts of vinyl-terminated silicone oil (20000 mPa·s), 25 parts of silica (Evonik R8200), 25 parts of polysilsesquioxane (m=30, 55% propylene oxide) were added to a planetary mixer or high-speed disperser and stirred under vacuum for 1 hour. Then, 25 parts of polyether block silicone oil (a=5, b=6, c=20), 10 parts of polyether modified hydrogen-containing silicone oil (d=0, e=5, f=5, n=2), 20 parts of crosslinking agent (viscosity 150 mPa·s, hydrogen content 0.75%), and 2 parts of alkynylcyclohexanol were added and stirred under vacuum for 0.5 hours. Finally, 4 parts of platinum-vinyl complex were added, stirred, degassed, and impurities were filtered to obtain primer.

[0075] (3) Coat the release paper with a surface adhesive with a thickness of 30 μm, and then bake at 130°C for 1 min (first layer);

[0076] (4) Apply a base coat to the surface of the top coat, with a thickness of 150 μm, and then bake at 130 °C for 1 min (second layer).

[0077] (5) After curing, another layer of base adhesive is coated on the surface of the base adhesive with a thickness of 70μm (third layer). Then, the base fabric is bonded to the base adhesive and baked at 130℃ for 3 minutes. The release paper is then peeled off to obtain water-permeable silicone synthetic leather.

[0078] Example 6

[0079] A water-permeable organosilicon synthetic leather and its preparation method.

[0080] Includes the following steps:

[0081] (1) Preparation of the face adhesive: By mass, 100 parts of vinyl-terminated silicone oil (80000 mPa·s), 10 parts of silica (Wacker H2000), and 60 parts of polysilsesquioxane (m=10, 50% of epoxypropoxypropyl) were added to a planetary mixer or high-speed disperser and stirred under vacuum for 1 hour. Then, 20 parts of polyether block silicone oil (a=30, b=10, c=1), 20 parts of polyether modified hydrogen-containing silicone oil (d=0, e=10, f=10, n=10), 20 parts of crosslinking agent (viscosity 200 mPa·s, hydrogen content 0.36%) and 1 part of alkynylcyclohexanol were added and stirred under vacuum for 0.5 hours. Finally, 2 parts of platinum-vinyl complex were added, stirred, degassed, and impurities were filtered to obtain the face adhesive.

[0082] (2) Preparation of primer: By weight, 100 parts of vinyl-terminated silicone oil (20000 mPa·s), 25 parts of silica (Evonik R8200), 25 parts of polysilsesquioxane (m=30, propylene oxide content of 55%) were added to a planetary mixer or high-speed disperser and stirred under vacuum for 1 hour. Then, 10 parts of polyether block silicone oil (a=30, b=10, c=50), 20 parts of polyether modified hydrogen-containing silicone oil (d=5, e=20, f=10, n=2), 10 parts of crosslinking agent (viscosity 150 mPa·s, hydrogen content 0.75%), and 2 parts of alkynylcyclohexanol were added and stirred under vacuum for 0.5 hours. Finally, 4 parts of platinum-vinyl complex were added, stirred, degassed, and impurities were filtered to obtain primer.

[0083] (3) Coat the release paper with a surface adhesive with a thickness of 40 μm, and then bake at 130°C for 2 min (first layer);

[0084] (4) Apply a base coat to the surface of the top coat, with a thickness of 110 μm, and then bake at 130°C for 2 min (second layer).

[0085] (5) After curing, another layer of base adhesive is coated on the surface of the base adhesive with a thickness of 90μm (third layer). Then, the base fabric is bonded to the base adhesive and baked at 130℃ for 4min. The release paper is then peeled off to obtain water-permeable silicone synthetic leather.

[0086] Comparative Example 1

[0087] A water-permeable organosilicon synthetic leather and its preparation method.

[0088] The difference between Comparative Example 1 and Example 1 is that no polysilsesquioxane was added.

[0089] Comparative Example 2

[0090] A water-permeable organosilicon synthetic leather and its preparation method.

[0091] The difference between Comparative Example 2 and Example 1 is that the glycidoxypropyl group of polysilsesquioxane is replaced with methyl, and the methacryloyloxypropyl group of polysilsesquioxane is replaced with vinyl.

[0092] Comparative Example 3

[0093] A water-permeable organosilicon synthetic leather and its preparation method.

[0094] The difference between Comparative Example 3 and Example 1 is that no polyether block silicone oil is added.

[0095] Comparative Example 4

[0096] A water-permeable organosilicon synthetic leather and its preparation method.

[0097] The difference between Comparative Example 4 and Example 1 is that the polyether-modified hydrogen-containing silicone oil was replaced with a hydrogen-containing silicone oil with the same hydrogen content.

[0098] Comparative Example 5

[0099] A water-permeable organosilicon synthetic leather and its preparation method.

[0100] The difference between Comparative Example 5 and Example 1 is that no polyether block silicone oil was added, and the polyether modified hydrogen-containing silicone oil was replaced with a hydrogen-containing silicone oil with the same hydrogen content.

[0101] Comparative Example 6

[0102] A water-permeable organosilicon synthetic leather and its preparation method.

[0103] The difference between Comparative Example 6 and Example 1 is that the glycidyl group of polysilsesquioxane is replaced with methyl, the methacryloyloxypropyl group of polysilsesquioxane is replaced with vinyl, polyether block silicone oil is not added, and the polyether modified hydrogen-containing silicone oil is replaced with hydrogen-containing silicone oil with the same hydrogen content.

[0104] Test results:

[0105] The performance of the prepared silicone synthetic leather was tested in accordance with the standards QB / T 1811 and GB / T 19089, and the results are shown in Table 1.

[0106] Table 1 Performance tests of Examples 1-6 and Comparative Examples 1-6

[0107]

[0108] As can be seen from Table 1 above, the water-permeable silicone synthetic leathers prepared in Examples 1-6 all achieved a water permeability of 120 g / (m³). 2 ·h) or above, Martindale wear-resistant for 100,000 cycles (12kPa) without damage.

[0109] Comparative Example 1, without the addition of polysilsesquioxane, resulted in silicone synthetic leather with poor abrasion resistance; Martindale leather broke after only 10,000 cycles. Comparative Example 2 used ordinary methyl vinyl polysilsesquioxane as a reinforcing filler, without introducing hydrophilic functional groups; it only increased the strength of the silicone synthetic leather but affected its water vapor permeability. Comparative Example 3, without polyether block silicone oil, affected the affinity of silicone rubber for water, resulting in poor water vapor permeability of the silicone synthetic leather. Comparative Example 4 replaced the polyether-modified hydrogen-containing silicone oil with a hydrogen-containing silicone oil of the same hydrogen content, affecting the affinity of silicone rubber for water. The synthetic leather produced had poor water vapor permeability. Comparative Example 5, without polyether block silicone oil and replacing the polyether-modified hydrogen-containing silicone oil with a hydrogen-containing silicone oil of the same hydrogen content without adding a tackifier, showed a significant decrease in the silicone rubber's affinity for water, resulting in poor water vapor permeability of the silicone synthetic leather. Comparative Example 6 replaced the glycidoxypropyl group of polysilsesquioxane with methyl groups and the methacryloyloxypropyl group with vinyl groups, without adding polyether block silicone oil, and replaced the polyether-modified hydrogen-containing silicone oil with a hydrogen-containing silicone oil of the same hydrogen content. This was equivalent to not optimizing the water vapor permeability of the silicone rubber, resulting in silicone synthetic leather with poor water vapor permeability. However, the methods used in Examples 1-6 all yielded silicone synthetic leather with better performance.

[0110] The preferred embodiments of the present invention have been described in detail above. It should be understood that those skilled in the art can make numerous modifications and variations based on the concept of the present invention without creative effort. Therefore, any technical solutions obtained by those skilled in the art through logical analysis, reasoning, or limited experimentation based on the concept of the present invention and on the existing technology should be within the scope of protection defined by the claims.

Claims

1. A method for preparing a water-permeable organosilicon synthetic leather, characterized in that, Includes the following steps: (1) Coat the release paper with a thickness of 10~50μm of adhesive and heat it at 110~140℃ for 1~3min; (2) Apply a base coat with a thickness of 80~200μm to the surface of the cured top coat and heat it at 110~140℃ for 1~3min; (3) Apply a base coat with a thickness of 50~100μm to the surface of the cured base coat, attach the base fabric, heat and cure at 110~140℃ for 3~8min, peel off the release paper, and obtain water-permeable silicone synthetic leather. The preparation method of the adhesive includes the following steps: by weight, 80-120 parts of vinyl-terminated silicone oil, 5-20 parts of silica, and 30-70 parts of polysilsesquioxane are mixed and vacuum stirred for 0.5-2 hours. Then, 5-20 parts of polyether block silicone oil, 10-30 parts of polyether modified hydrogen-containing silicone oil, 5-20 parts of crosslinking agent, and 0.1-5 parts of inhibitor are added and vacuum stirred for 0.1-1 hours. Finally, 0.2-5 parts of catalyst are added, stirred, bubbles are removed, and impurities are filtered to obtain the adhesive. The preparation method of the primer includes the following steps: by weight, 80-120 parts of vinyl-terminated silicone oil, 10-35 parts of silica, and 5-40 parts of polysilsesquioxane are mixed and vacuum stirred for 0.5-2 hours. Then, 5-25 parts of polyether block silicone oil, 10-25 parts of polyether modified hydrogen-containing silicone oil, 5-20 parts of crosslinking agent, and 0.1-5 parts of inhibitor are added and vacuum stirred for 0.1-1 hours. Finally, 0.2-5 parts of catalyst are added, stirred, bubbles are removed, and impurities are filtered to obtain the primer. The structural formula of the polysilsesquioxane is shown in Formula I: Formula I; Where m is an integer from 2 to 30; R is or The proportion of R is 20-60%.

2. The preparation method according to claim 1, characterized in that, The vinyl content of the terminal vinyl silicone oil is 0.06~0.2wt%; the viscosity is 5000~100000mPa·s.

3. The preparation method according to claim 1, characterized in that, The structural formula of the polyether block silicone oil is shown in Formula II: Formula II; Where a is an integer from 0 to 30; b is an integer from 1 to 10; and c is an integer from 1 to 50.

4. The preparation method according to claim 1, characterized in that, The structural formula of the polyether-modified hydrogen-containing silicone oil is shown in Formula III: Formula III; Where d is an integer from 0 to 30; e is an integer from 5 to 30; f is an integer from 5 to 30; and n is an integer from 2 to 10.

5. The preparation method according to claim 1, characterized in that, The crosslinking agent is a hydrogen-containing silicone oil with a viscosity of 30~200 mPa·s and a hydrogen content of 0.36%~1.2%.

6. The preparation method according to claim 1, characterized in that, The inhibitor is at least one of polyethylenesiloxane, alkynyl alcohol, and maleate ester.

7. A water-permeable silicone synthetic leather, characterized in that, The water-permeable silicone synthetic leather is prepared by any one of claims 1 to 6.

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