A kind of hydrophobic organosilicon leather and its manufacturing process

Abstract

The present invention discloses a hydrophobic silicone leather and a production process thereof, and belongs to the technical field of silicone leather production. The silicone leather prepared by the present invention comprises a surface layer, an intermediate layer, a functional layer and a base layer from top to bottom, wherein phenyl, amide group and polydimethylsiloxane side chain are introduced into the molecular structure of the modified hydrophobic resin in the surface layer, which has the advantages of improving the hydrophobicity and wear resistance of the surface layer. Peppermint oil is added to the functional layer for blending, which effectively improves the antibacterial properties of the leather and gives the leather a fragrance. In the four-layer structure of the silicone leather prepared by the present invention, the fiber material and the silicone resin adhesive are alternately laminated to form a breathable channel of a three-dimensional structure, while having excellent hydrophobic and wear resistance.

Description

Technical Field

[0001] The invention belongs to the technical field of organosilicon leather production, and in particular relates to hydrophobic organosilicon leather and a production process thereof. Background Art

[0002] Silicone leather belongs to the new material industry developed in the 21st century. It uses solvent-free and water-free technology to coat and bond silicone on various substrates to make synthetic leather. This solvent-free technology not only avoids the air pollution caused by the large amount of solvent volatilization used in traditional leather production, but also reduces energy consumption and greenhouse gas emissions. In contrast, the production process of genuine leather, PU and PVC requires the use of various chemical reagents and solvents, which not only consumes a lot of energy, but also produces a large amount of waste gas, wastewater and solid waste, causing serious impact on the environment.

[0003] Silicone leather, as a kind of artificial leather, uses silicone as the main raw material and is closely combined with substrates such as microfibers, non-woven fabrics or knitted fabrics through a precise bonding process. It has good weather resistance, flame retardancy, anti-fouling and easy care properties, and is suitable for a variety of industry applications, such as hotels, medical care, home furnishings, and automobiles. These properties make silicone leather more environmentally friendly and durable during use, reducing the frequency of replacement and the generation of waste.

[0004] Silicone leather is mainly made of silicon-based polymers (polydimethylsiloxane). The Si-O bond structure of the main chain of the silicone material gives silicone leather good flexibility and elasticity. At the same time, the silicone molecular chains of silicone leather are arranged in a spiral shape, with the methyl group facing outward, surrounding the main chain of silicon oxygen. This structure makes silicone leather hydrophobic and can effectively resist the erosion of water and stains, thereby maintaining long-term cleanliness and beauty. However, at present, silicone leather generally has the problem that the strength of the surface layer is weaker than that of PU synthetic leather, and the leather surface has high friction and poor air permeability. With the gradual improvement of industry standards, ordinary hydrophobic properties can no longer meet the needs. Therefore, it is of great significance to develop a silicone leather with excellent hydrophobic properties, wear resistance and air permeability. Summary of the invention

[0005] The purpose of the present invention is to provide a hydrophobic silicone leather and a production process thereof, which can greatly improve the wear resistance of the silicone leather while ensuring that the silicone leather has excellent hydrophobic properties.

[0006] The purpose of the present invention can be achieved through the following technical solutions:

[0007] The present invention provides a hydrophobic silicone leather, wherein the leather comprises a surface layer, an intermediate layer, a functional layer and a base layer from top to bottom;

[0008] The raw materials of the surface layer include, by mass:

[0009] 20-35 parts of silicone epoxy resin, 50-65 parts of phenyl silicone resin, 10-20 parts of modified hydrophobic silicone resin, 10-20 parts of antistatic filler, 8-15 parts of crosslinking agent, 0.2-2 parts of curing accelerator, 0.05-1 parts of catalyst, 0.01-0.05 parts of inhibitor and 0.5-5 parts of color paste;

[0010] The structure of the modified hydrophobic silicone resin is:

[0011] ;

[0012] Wherein, m is an integer of 90-150, and n is an integer of 5-100.

[0013] Preferably, the surface layer has a thickness of 50-100 μm, the intermediate layer has a thickness of 0.25-0.3 mm, the functional layer has a thickness of 10-30 μm, and the base layer has a thickness of 0.4-0.5 mm.

[0014] Preferably, the epoxy value of the silicone epoxy resin is 0.42-0.51. As the epoxy value increases, its friction coefficient increases, and as the epoxy value decreases, its viscosity and mechanical properties decrease. Selecting a moderate epoxy value can ensure that the material has excellent comprehensive properties.

[0015] Preferably, the phenyl silicone resin is methylphenyl silicone resin.

[0016] Preferably, the modified hydrophobic silicone resin is prepared as follows:

[0017] (1) Adding hydroxyl-terminated polydimethylsiloxane and 3-isocyanatepropyltrimethoxysilane in a molar ratio of 1:1.01 to a reaction kettle, and adding dibutyltin dilaurate in an amount of 1% by weight of the total weight of the hydroxyl-terminated polydimethylsiloxane and 3-isocyanatepropyltrimethoxysilane, and polymerizing at 50° C. for 1 hour to obtain polymer A;

[0018] The structure of the polymer A is:

[0019] ;

[0020] Wherein, m is 90-150;

[0021] (2) Polymer A, phenyltrimethoxysilane and methyltrimethoxysilane are put into a reactor in a molar ratio of 1:1:2, and a 30 wt% hydrochloric acid aqueous solution is added, the mass of the hydrochloric acid aqueous solution is 50% of the total mass of polymer A, phenyltrimethoxysilane and methyltrimethoxysilane, and the reaction is carried out at 60°C for 2 hours. Hexamethyldisiloxane is then added, the mass of hexamethyldisiloxane is 3% of the total mass of polymer A, phenyltrimethoxysilane and methyltrimethoxysilane, and the temperature is raised to 80°C to continue the reaction for 1 hour. At the same time, the generated water is removed by reflux, and the small molecules are removed by reduced pressure distillation to obtain a modified hydrophobic silicone resin.

[0022] Due to the long chain and polydimethylsiloxane on the side chain of the modified hydrophobic silicone resin, its surface energy is low and its compatibility with the silicone epoxy resin is poor, which makes it easy to enrich on the coating surface during the curing process, thereby reducing the surface energy of the coating. The introduction of phenyl in the side chain can promote the compatibility of the modified hydrophobic silicone resin and phenyl silicone resin, making it closely combined with the coating matrix, reducing the surface roughness while also having the effect of reducing the surface energy. The addition of methyltrimethoxysilane in the main chain condensation can increase the condensation degree, and hexamethyldisiloxane as a capping agent consumes Si-OH groups and improves the stability of the silicone resin.

[0023] Preferably, the antistatic filler is at least one of carbon black, graphene and mica powder;

[0024] Preferably, the cross-linking agent is polymethylhydrogensiloxane;

[0025] Preferably, the curing accelerator is at least one of ethylenediamine, diethylenetriamine and triethylenetetramine.

[0026] Preferably, the catalyst is one of chloroplatinic acid ethanol solution, chloroplatinic acid isopropanol solution and chloroplatinic acid tetrahydrofuran solution, wherein the Pt atomic content is 1000-10000 ppm.

[0027] Preferably, the inhibitor is at least one of maleate and fumarate.

[0028] Preferably, the color paste is a pigment dispersed in vinyl polydimethylsiloxane.

[0029] Preferably, the middle layer is a non-woven fabric blended with polyester and spandex;

[0030] Preferably, the raw materials of the functional layer include, by weight:

[0031] 60-80 parts of divinyl polydimethylsiloxane, 10-20 parts of methyl vinyl MQ type silicone resin, 25-45 parts of anhydrous ethanol, 2-8 parts of peppermint oil, 5-15 parts of functional layer crosslinking agent, 0.01-0.5 parts of functional layer catalyst, 0.005-0.01 parts of functional layer inhibitor, 15-35 parts of functional layer filler and 0.01-3 parts of functional layer color paste.

[0032] Peppermint oil is a light grass green liquid or light yellow clear liquid with a strong mint aroma. It has antibacterial, antiviral, anti-inflammatory and antioxidant properties. It can give the material an aroma while improving its antibacterial properties.

[0033] Preferably, the vinyl mole percentage of the divinyl polydimethylsiloxane is 0.2-0.3%, and the M / Q ratio of the methyl vinyl MQ type silicone resin is 0.8;

[0034] The functional layer cross-linking agent is polymethyl hydrogen siloxane;

[0035] The functional layer catalyst is a vinyl platinum complex, wherein the mass fraction of platinum is 3-4.5%;

[0036] The vinyl platinum complex can inhibit the side reaction between vinyl and hydrogen and avoid the formation of black substances.

[0037] The inhibitor is at least one of polyvinyl polysiloxane, 4-trimethylsilyl-3-butyn-2-ol, phenyltris(methylbutynyloxy)silane, vinyltris(methylbutynyloxy)-silane and methyltris(cyclohexynyloxy)silane;

[0038] The functional layer filler is at least one of hollow glass microspheres, spherical calcium carbonate, spherical silicon dioxide and spherical zinc oxide. Compared with the inorganic filler with a sheet structure, the inorganic filler with a spherical structure can increase the gap between the polymers and improve the air permeability;

[0039] The functional layer color paste is a pigment dispersed in vinyl polydimethylsiloxane.

[0040] Preferably, the base layer is one of needle-punched cloth, woven cloth and spunlace cloth.

[0041] The present invention also provides a process for preparing hydrophobic organosilicon leather, which is used to prepare the hydrophobic organosilicon leather, comprising the following steps:

[0042] S1. Mix the raw materials of the functional layer evenly according to the ratio, apply them on the upper surface of the base layer, and attach the intermediate layer to the upper surface of the functional layer, and cure at 60-80°C for 5-10 minutes;

[0043] S2. Mix the raw materials of the surface layer evenly according to the ratio, apply them on the release paper, and laminate the release paper to the upper surface of the middle layer. Curing at 80-100° C. for 10-20 min, peeling off the release paper, and cooling to room temperature to obtain the finished silicone leather product.

[0044] Beneficial effects of the present invention:

[0045] (1) The organic silicone leather surface layer raw material prepared by the present invention includes organic silicone epoxy resin, phenyl silicone resin and modified hydrophobic silicone resin. The side chains of the modified hydrophobic silicone resin structure contain phenyl and polydimethylsiloxane, which can reduce the surface energy of the surface layer while improving the mechanical properties. The amide groups on the side chains can increase the softness of the surface layer. The prepared surface layer raw material contains a variety of different groups, which endows the surface layer with good hydrophobicity, wear resistance and temperature resistance.

[0046] (2) The functional layer raw material of the silicone leather of the present invention contains vinyl, and the functional layer has excellent bonding properties. By adding peppermint oil, the functional layer is given antibacterial properties, and by adding fillers, the porosity of the raw material of the functional layer is increased to enhance the breathability.

[0047] (3) The organic silicone leather prepared by the present invention comprises a four-layer structure, wherein the base layer and the middle layer are fiber cloth, and the rubber material and the fiber cloth are alternately bonded to form a three-dimensional breathable channel. The base layer and the middle layer give the leather higher mechanical properties and wear resistance. The surface layer and the functional layer protect the fiber cloth material from damage while achieving multi-layer efficient bonding. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] The present invention will be further described below in conjunction with the accompanying drawings.

[0049] Figure 1 Schematic diagram of the structure of the organosilicon leather prepared in the embodiment of the present invention. DETAILED DESCRIPTION

[0050] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0051] Example 1

[0052] Preparation of modified hydrophobic silicone resin:

[0053] Step 1: Add hydroxyl-terminated polydimethylsiloxane and 3-isocyanatepropyltrimethoxysilane into a reaction kettle at a molar ratio of 1:1.01, and add 1% of dibutyltin dilaurate as a catalyst, and perform polymerization reaction at 50° C. for 1 hour to obtain polymer A;

[0054] Step 2: Put polymer A, phenyltrimethoxysilane and methyltrimethoxysilane into a reactor in a molar ratio of 1:1:2, and add 30wt% hydrochloric acid aqueous solution, the mass of the hydrochloric acid aqueous solution is 50% of the total mass of polymer A, phenyltrimethoxysilane and methyltrimethoxysilane, react at 60°C for 2h, then add hexamethyldisiloxane, the mass of hexamethyldisiloxane is 3% of the total mass of polymer A, phenyltrimethoxysilane and methyltrimethoxysilane, heat to 80°C and continue to react for 1h, while separating and refluxing to remove the generated water, and remove small molecules by reduced pressure distillation to obtain a modified hydrophobic silicone resin.

[0055] Example 2

[0056] This embodiment provides a hydrophobic silicone leather, which comprises a surface layer, an intermediate layer, a functional layer and a base layer from top to bottom, wherein the raw materials of the surface layer include, by weight:

[0057] 35 parts of silicone epoxy resin (epoxy value 0.42-0.51), 50 parts of methylphenyl silicone resin, 10 parts of modified hydrophobic silicone resin prepared in Example 1, 15 parts of carbon black, 10 parts of polymethyl hydrogen siloxane, 1 part of diethylenetriamine, 0.5 parts of chloroplatinic acid ethanol solution (Pt atom content of 5000ppm), 0.03 parts of maleate and 3 parts of color paste.

[0058] The middle layer is a non-woven fabric blended with polyester and spandex.

[0059] The raw materials of the functional layer include, by weight:

[0060] 80 parts of divinyl polydimethylsiloxane (vinyl molar percentage is 0.2-0.3%), 10 parts of methyl vinyl MQ type silicone resin (M / Q ratio is 0.8), 25 parts of anhydrous ethanol, 5 parts of peppermint oil, 10 parts of polymethyl hydrogen siloxane, 0.1 parts of platinum-divinyltetramethyldisiloxane, 0.008 parts of 4-trimethylsilyl-3-butyn-2-ol, 20 parts of hollow glass microspheres and 1 part of functional layer color paste (pigment dispersed in vinyl polydimethylsiloxane).

[0061] The base layer is polyester needle-punched cloth.

[0062] Preparation of silicone leather:

[0063] S1. Mix the raw materials of the functional layer evenly according to the ratio, apply them on the upper surface of the base layer, and attach the intermediate layer to the upper surface of the functional layer, and cure at 60°C for 10 minutes;

[0064] S2. Mix the raw materials of the surface layer evenly according to the ratio, apply them on the release paper, and laminate the release paper to the upper surface of the middle layer. Curing at 80° C. for 20 min, peeling off the release paper, and cooling to room temperature to obtain the finished silicone leather product.

[0065] The finished organic silicone leather product prepared in this embodiment has a surface layer thickness of 50 μm, a middle layer thickness of 0.3 mm, a functional layer thickness of 30 μm, and a base layer thickness of 0.5 mm.

[0066] Example 3

[0067] The difference from Example 2 is that the raw material ratio of the surface layer is different, and the other steps are the same as Example 2. In terms of mass fraction, the raw materials of the organic silicon leather surface layer provided in this example include:

[0068] 30 parts of silicone epoxy resin (epoxy value 0.42-0.51), 50 parts of methylphenyl silicone resin, 15 parts of modified hydrophobic silicone resin prepared in Example 1, 15 parts of carbon black, 10 parts of polymethyl hydrogen siloxane, 1 part of diethylenetriamine, 0.5 parts of chloroplatinic acid ethanol solution (Pt atom content of 5000ppm), 0.03 parts of maleate and 3 parts of color paste.

[0069] Example 4

[0070] The difference from Example 2 is that the raw material ratio of the surface layer is different, and the other steps are the same as Example 2. In terms of mass fraction, the raw materials of the organic silicon leather surface layer provided in this example include:

[0071] 25 parts of silicone epoxy resin (epoxy value 0.42-0.51), 50 parts of methylphenyl silicone resin, 20 parts of modified hydrophobic silicone resin prepared in Example 1, 15 parts of carbon black, 10 parts of polymethyl hydrogen siloxane, 1 part of diethylenetriamine, 0.5 parts of chloroplatinic acid ethanol solution (Pt atom content of 5000ppm), 0.03 parts of maleate and 3 parts of color paste.

[0072] Example 5

[0073] The difference from Example 2 is that the raw material ratio of the surface layer is different, and the other steps are the same as Example 2. In terms of mass fraction, the raw materials of the organic silicon leather surface layer provided in this example include:

[0074] 25 parts of organic silicon epoxy resin (epoxy value is 0.42-0.51), 60 parts of methylphenyl silicone resin, 10 parts of modified hydrophobic silicone resin prepared in Example 1, 15 parts of carbon black, 10 parts of polymethyl hydrogen siloxane, 1 part of diethylenetriamine, 0.5 parts of chloroplatinic acid ethanol solution (Pt atom content is 5000ppm), 0.03 parts of maleate and 3 parts of color paste.

[0075] Example 6

[0076] The difference from Example 2 is that the raw material ratio of the surface layer is different, and the other steps are the same as Example 2. In terms of mass fraction, the raw materials of the organic silicon leather surface layer provided in this example include:

[0077] 20 parts of silicone epoxy resin (epoxy value 0.42-0.51), 65 parts of methylphenyl silicone resin, 10 parts of modified hydrophobic silicone resin prepared in Example 1, 15 parts of carbon black, 10 parts of polymethyl hydrogen siloxane, 1 part of diethylenetriamine, 0.5 parts of chloroplatinic acid ethanol solution (Pt atom content of 5000ppm), 0.03 parts of maleate and 3 parts of color paste.

[0078] Example 7

[0079] The difference from Example 2 is that the raw material ratio of the functional layer is different, and the other steps are the same as Example 2. In terms of mass fraction, the raw materials of the organic silicon leather functional layer provided in this example include:

[0080] 80 parts of divinyl polydimethylsiloxane (vinyl molar percentage is 0.2-0.3%), 10 parts of methyl vinyl MQ type silicone resin (M / Q ratio is 0.8), 25 parts of anhydrous ethanol, 2 parts of peppermint oil, 10 parts of polymethyl hydrogen siloxane, 0.1 parts of platinum-divinyltetramethyldisiloxane, 0.008 parts of 4-polyvinyl polysiloxane, 20 parts of hollow glass microspheres and 1 part of functional layer color paste (pigment dispersed in vinyl polydimethylsiloxane).

[0081] Example 8

[0082] The difference from Example 2 is that the raw material ratio of the functional layer is different, and the other steps are the same as Example 2. In terms of mass fraction, the raw materials of the organic silicon leather functional layer provided in this example include:

[0083] 80 parts of divinyl polydimethylsiloxane (vinyl molar percentage is 0.2-0.3%), 10 parts of methyl vinyl MQ type silicone resin (M / Q ratio is 0.8), 25 parts of anhydrous ethanol, 8 parts of peppermint oil, 10 parts of polymethyl hydrogen siloxane, 0.1 parts of platinum-divinyltetramethyldisiloxane, 0.008 parts of 4-trimethylsilyl-3-butyn-2-ol, 20 parts of hollow glass microspheres and 1 part of functional layer color paste (pigment dispersed in vinyl polydimethylsiloxane).

[0084] Example 9

[0085] This embodiment provides a hydrophobic silicone leather, which comprises a surface layer, an intermediate layer, a functional layer and a base layer from top to bottom, wherein the raw materials of the surface layer include, by weight:

[0086] 35 parts of silicone epoxy resin (epoxy value 0.42-0.51), 50 parts of methylphenyl silicone resin, 10 parts of modified hydrophobic silicone resin prepared in Example 1, 10 parts of graphene, 15 parts of polymethylhydrogensiloxane, 2 parts of ethylenediamine, 0.05 parts of chloroplatinic acid ethanol solution (Pt atom content of 10000ppm), 0.05 parts of fumarate and 5 parts of color paste.

[0087] The middle layer is a non-woven fabric blended with polyester and spandex.

[0088] The raw materials of the functional layer include, by weight:

[0089] 70 parts of divinyl polydimethylsiloxane (vinyl molar percentage is 0.2-0.3%), 20 parts of methyl vinyl MQ type silicone resin (M / Q ratio is 0.8), 35 parts of anhydrous ethanol, 5 parts of peppermint oil, 15 parts of polymethyl hydrogen siloxane, 0.5 parts of platinum-divinyltetramethyldisiloxane, 0.01 parts of tetramethyltetravinylcyclotetrasiloxane, 35 parts of calcium carbonate and 3 parts of functional layer color paste (pigment dispersed in vinyl polydimethylsiloxane).

[0090] The base layer is polyester needle-punched cloth.

[0091] Preparation of silicone leather:

[0092] S1. Mix the raw materials of the functional layer evenly according to the proportion, apply them on the upper surface of the base layer, and attach the intermediate layer to the upper surface of the functional layer, and cure at 70°C for 8 minutes;

[0093] S2. Mix the raw materials of the surface layer evenly according to the ratio, apply them on the release paper, and laminate the release paper to the upper surface of the middle layer. Curing at 90° C. for 15 min, peeling off the release paper, and cooling to room temperature to obtain the finished silicone leather product.

[0094] The finished silicone leather product prepared in this embodiment has a surface layer thickness of 80 μm, a middle layer thickness of 0.28 mm, a functional layer thickness of 20 μm, and a base layer thickness of 0.46 mm.

[0095] Example 10

[0096] This embodiment provides a hydrophobic silicone leather, which comprises a surface layer, an intermediate layer, a functional layer and a base layer from top to bottom, wherein the raw materials of the surface layer include, by weight:

[0097] 35 parts of organic silicon epoxy resin (epoxy value 0.42-0.51), 50 parts of methylphenyl silicone resin, 10 parts of modified hydrophobic silicone resin prepared in Example 1, 20 parts of mica powder, 8 parts of polymethyl hydrogen siloxane, 0.2 parts of triethylenetetramine, 1 part of chloroplatinic acid ethanol solution (Pt atom content of 1000ppm), 0.01 parts of maleate and 0.5 parts of color paste.

[0098] The middle layer is a non-woven fabric blended with polyester and spandex.

[0099] The raw materials of the functional layer include, by weight:

[0100] 75 parts of divinyl polydimethylsiloxane (vinyl molar percentage is 0.2-0.3%), 15 parts of methyl vinyl MQ type silicone resin (M / Q ratio is 0.8), 45 parts of anhydrous ethanol, 5 parts of peppermint oil, 5 parts of polymethyl hydrogen siloxane, 0.01 parts of platinum-divinyltetramethyldisiloxane, 0.005 parts of 4-trimethylsilyl-3-butyn-2-ol, 15 parts of silicon dioxide and 0.01 parts of functional layer color paste (pigment dispersed in vinyl polydimethylsiloxane).

[0101] The base layer is polyester needle-punched cloth.

[0102] Preparation of silicone leather:

[0103] S1. Mix the raw materials of the functional layer evenly according to the proportion, apply them on the upper surface of the base layer, and attach the intermediate layer to the upper surface of the functional layer, and cure at 80°C for 5 minutes;

[0104] S2. Mix the raw materials of the surface layer evenly according to the ratio, apply them on the release paper, and laminate the release paper to the upper surface of the middle layer. Curing at 100° C. for 10 min, peeling off the release paper, and cooling to room temperature to obtain the finished silicone leather product.

[0105] The finished organic silicone leather product prepared in this embodiment has a surface layer thickness of 100 μm, a middle layer thickness of 0.25 mm, a functional layer thickness of 10 μm, and a base layer thickness of 0.4 mm.

[0106] Comparative Example 1

[0107] The silicone leather was prepared according to the preparation method provided in Example 1 of Patent No. CN115595800A.

[0108] Comparative Example 2

[0109] The silicone leather was prepared according to the preparation method provided in Example 1 of Patent No. CN115287911A.

[0110] Performance tests were performed on Examples 1 to 10, Comparative Example 1 and Comparative Example 2, and the results are shown in Table 1:

[0111] The wear resistance test was carried out with reference to "GB / T 39507-2020 Physical and mechanical tests of leather - Determination of wear resistance: Martindale ball-on-disc method", using a CS-17 grinding wheel and a test load of 1000g.

[0112] The waterproof performance test is carried out with reference to "GB / T 4689.21-2008 Physical and mechanical tests on leather - Determination of static water absorption".

[0113] The antibacterial performance test refers to "GB / T 43722.1-2024 Determination of antibacterial properties of leather Part 1: Membrane contact method", and the bacteria species is Staphylococcus aureus.

[0114] The peel strength test was carried out with reference to "YBB00102003-2015 Peel Strength Determination Method". The sample cutting specification was 15.0mm×200mm, and 5 identical samples were tested. The composite direction was longitudinal. The sample should be at a temperature of (23±2)℃ and a relative humidity of (50±5)%. The composite layer (functional layer in the embodiment) and the substrate (base layer in the embodiment) were pre-peeled 50mm in the length direction of the sample, and the peeled part should not have obvious damage. The stretching machine speed was 300-30mm / min until it was broken. The peeling curve during the peeling process was observed.

[0115] The air permeability test is carried out with reference to "QB / T 2799-2006 Leather Air Permeability Determination Method".

[0116]

[0117] As can be seen from Table 1, the silicone leather prepared in Example 2-Example 4 has significantly improved hydrophobicity and wear resistance as the proportion of modified hydrophobic silicone resin in the surface raw material increases. In combination with Example 2, the proportion of phenyl silicone resin in the surface layer increases in Example 5 and Example 6. Due to the increase in the phenyl content, the bonding strength of the rubber material is improved, and the hydrophobic effect of the phenyl can improve the hydrophobicity, but due to the combination of modified hydrophobic resin and phenyl silicone resin, it is not easy to migrate to the coating surface, and the improvement of hydrophobicity is weak. In combination with Example 2, Example 7 and Example 8, increasing the dosage of peppermint oil in the functional layer can significantly improve the antibacterial properties of the leather. In Example 9 and Example 10, due to the different dosages of the additives in the fabric and the functional layer, the thickness of each layer is different, and its various properties are compared with Example 2. There are changes, but the comprehensive performance is more obvious than that of Comparative Example 1 and Comparative Example 2.

[0118] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0119] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A hydrophobic silicone leather, It is characterized in that The leather comprises a surface layer, a middle layer, a functional layer and a base layer from top to bottom; The raw materials of the surface layer include, by mass: 20-35 parts of silicone epoxy resin, 50-65 parts of phenyl silicone resin, 10-20 parts of modified hydrophobic silicone resin, 10-20 parts of antistatic filler, 8-15 parts of crosslinking agent, 0.2-2 parts of curing accelerator, 0.05-1 parts of catalyst, 0.01-0.05 parts of inhibitor and 0.5-5 parts of color paste; The structure of the modified hydrophobic silicone resin is: ； Wherein, m is 90-150, and n is an integer of 5-100; The middle layer is a non-woven fabric blended with polyester and spandex; The base layer is one of knitted fabric, woven fabric and spunlace fabric.

2. The hydrophobic silicone leather according to claim 1, It is characterized in that The surface layer has a thickness of 50-100 μm, the intermediate layer has a thickness of 0.25-0.3 mm, the functional layer has a thickness of 10-30 μm, and the base layer has a thickness of 0.4-0.5 mm.

3. The hydrophobic silicone leather according to claim 1, It is characterized in that The epoxy value of the organic silicon epoxy resin is 0.42-0.51, and the phenyl silicone resin is methyl phenyl silicone resin.

4. The hydrophobic silicone leather according to claim 1, It is characterized in that The preparation method of the modified hydrophobic silicone resin is as follows: (1) Adding hydroxyl-terminated polydimethylsiloxane and 3-isocyanatepropyltrimethoxysilane in a molar ratio of 1:1.01 to a reaction kettle, and adding dibutyltin dilaurate in an amount of 1% by weight of the total weight of the hydroxyl-terminated polydimethylsiloxane and 3-isocyanatepropyltrimethoxysilane, and polymerizing at 50° C. for 1 hour to obtain polymer A; The structure of the polymer A is: ； Wherein, m is 90-150; (2) Polymer A, phenyltrimethoxysilane and methyltrimethoxysilane are put into a reactor in a molar ratio of 1:1:2, and a 30 wt% hydrochloric acid aqueous solution is added, the mass of the hydrochloric acid aqueous solution is 50% of the total mass of polymer A, phenyltrimethoxysilane and methyltrimethoxysilane, and the reaction is carried out at 60°C for 2 hours. Hexamethyldisiloxane is then added, the mass of hexamethyldisiloxane is 3% of the total mass of polymer A, phenyltrimethoxysilane and methyltrimethoxysilane, and the temperature is raised to 80°C to continue the reaction for 1 hour. At the same time, the generated water is removed by reflux, and the small molecules are removed by reduced pressure distillation to obtain a modified hydrophobic silicone resin.

5. The hydrophobic silicone leather according to claim 1, It is characterized in that The antistatic filler is at least one of carbon black, graphene and mica powder; The cross-linking agent is polymethylhydrogensiloxane; The curing accelerator is at least one of ethylenediamine, diethylenetriamine and triethylenetetramine; The catalyst is one of chloroplatinic acid ethanol solution, chloroplatinic acid isopropanol solution and chloroplatinic acid tetrahydrofuran solution, wherein the Pt atom content is 1000-10000ppm; The inhibitor is at least one of maleate and fumarate; The color paste is a pigment dispersed in vinyl polydimethylsiloxane.

6. The hydrophobic silicone leather according to claim 1, It is characterized in that The raw materials of the functional layer include, by weight: 60-80 parts of divinyl polydimethylsiloxane, 10-20 parts of methyl vinyl MQ type silicone resin, 25-45 parts of anhydrous ethanol, 2-8 parts of peppermint oil, 5-15 parts of functional layer crosslinking agent, 0.01-0.5 parts of functional layer catalyst, 0.005-0.01 parts of functional layer inhibitor, 15-35 parts of functional layer filler and 0.01-3 parts of functional layer color paste.

7. The hydrophobic silicone leather according to claim 6, It is characterized in that The vinyl mole percentage of the divinyl polydimethylsiloxane is 0.2-0.3%, and the M / Q ratio of the methyl vinyl MQ type silicone resin is 0.8; The functional layer cross-linking agent is polymethyl hydrogen siloxane; The functional layer catalyst is a vinyl platinum complex, wherein the mass fraction of platinum is 3-4.5%; The inhibitor is at least one of polyvinyl polysiloxane, 4-trimethylsilyl-3-butyn-2-ol, phenyltris(methylbutynyloxy)silane, vinyltris(methylbutynyloxy)-silane and methyltris(cyclohexynyloxy)silane; The functional layer filler is at least one of hollow glass microspheres, spherical calcium carbonate, spherical silicon dioxide and spherical zinc oxide; The functional layer color paste is a pigment dispersed in vinyl polydimethylsiloxane.

8. A process for producing hydrophobic silicone leather. It is characterized in that The method for preparing the hydrophobic silicone leather according to any one of claims 1 to 7 comprises the following steps: S1. Mix the raw materials of the functional layer evenly according to the ratio, apply them on the upper surface of the base layer, and attach the intermediate layer to the upper surface of the functional layer, and cure at 60-80°C for 5-10 minutes; S2. Mix the raw materials of the surface layer evenly according to the ratio, apply them on the release paper, and laminate the release paper to the upper surface of the middle layer. Curing at 80-100° C. for 10-20 min, peeling off the release paper, and cooling to room temperature to obtain the finished silicone leather product.

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