Flame-retardant organic silicon leather and preparation method thereof

Abstract

The invention provides flame-retardant organic silicon leather and a preparation method thereof, and belongs to the technical field of organic silicon leather. The flame-retardant organic silicon leather comprises glass fiber base cloth and an organic silicon coating, and the organic silicon coating comprises the following components in parts by weight: 1000 parts of liquid organic silicon rubber, 80-100 parts of hydrogen-containing vinyl silicone oil, 0.8-2 parts of 1-acetylene cyclohexanol, 0.5-1 part of a platinum catalyst, 20-40 parts of color paste, 200-450 parts of aluminum hydroxide and 150-400 parts of magnesium hydroxide; the coating is prepared through step-by-step stirring and vacuumizing, and the coating is obtained through three-layer step-by-step coating and curing and fitting and forming with glass fiber base cloth. The organic silicon leather prepared by the preparation method disclosed by the invention not only shows excellent flame retardant property, but also keeps good mechanical strength and wear resistance.

Description

Technical Field

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

[0002] Silicone leather is a new type of eco-friendly leather made by coating or bonding silicone rubber to various base fabrics (such as polyester fiber, glass fiber, etc.). Compared with traditional PVC (polyvinyl chloride) leather or PU (polyurethane) leather, silicone leather has significant advantages such as being non-toxic and environmentally friendly, resistant to high and low temperatures, having excellent weather resistance, a comfortable feel against the skin, excellent physical properties, and being easy to clean and maintain. It is widely used in automotive interiors, home furniture, consumer electronics, medical care, and public transportation.

[0003] Despite its superior performance, silicone leather, as a polymer material, has a relatively low limiting oxygen index (LOI), classifying it as flammable or combustible. This significantly limits its application in scenarios with stringent flame-retardant requirements (such as aircraft interiors, high-speed rail carriages, and special protective equipment). When burning, traditional silicone leather decomposes and releases heat, potentially dripping and accelerating the spread of fire, posing a potential safety hazard.

[0004] Therefore, developing a new type of flame-retardant silicone leather that combines extremely high flame retardancy with excellent flexibility, abrasion resistance, weather resistance, comfortable feel, and environmental friendliness and non-toxicity is of great practical significance. Summary of the Invention

[0005] The main objective of this invention is to provide a flame-retardant silicone leather and its preparation method, thereby solving the problems mentioned in the background art. The silicone leather of this invention exhibits excellent flame retardancy, mechanical properties, and abrasion resistance.

[0006] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows: A flame-retardant silicone leather comprises a fiberglass base fabric and a silicone coating. The silicone coating, by weight, comprises 1000 parts liquid silicone rubber, 80-100 parts hydrogen-containing vinyl silicone oil, 0.8-2 parts 1-acetylenecyclohexanol, 0.5-1 parts platinum catalyst, 20-40 parts color paste, 200-450 parts aluminum hydroxide, and 150-400 parts magnesium hydroxide.

[0007] Preferably, the hydrogen-containing vinyl silicone oil has a viscosity of 15-50 cSt and a hydrogen content of 0.36%-0.79%.

[0008] Preferably, the particle size of the aluminum hydroxide and magnesium hydroxide is in the nanometer range.

[0009] Preferably, the amount of aluminum hydroxide and magnesium hydroxide added accounts for 40%-60% of the liquid silicone rubber.

[0010] Preferably, the mass ratio of aluminum hydroxide to magnesium hydroxide is 1:1.

[0011] Preferably, the color paste is an addition-type silica gel color paste.

[0012] A second aspect of this invention provides a method for preparing flame-retardant silicone leather, comprising the following steps: (1) Liquid silicone rubber, hydrogen-containing vinyl silicone oil, aluminum hydroxide, magnesium hydroxide, 1-acetylenecyclohexanol and color paste are added to a planetary mixer and mixed evenly to obtain a mixture; (2) After adding platinum catalyst to the above mixture and stirring until homogeneous, an organosilicon coating is obtained; (3) The above-mentioned silicone coating is applied to the release paper, and then bonded to the fiberglass base cloth. After high-temperature curing, flame-retardant silicone leather is obtained.

[0013] Preferably, the mixing time in step (1) is 10-20 min and vacuuming is performed at room temperature.

[0014] Preferably, the mixing time in step (2) is 20-40 min and vacuuming is performed at room temperature.

[0015] Preferably, in step (3), the number of coating layers of the silicone coating is 3, and the thickness of each layer is 0.1 mm. After the first layer is cured at high temperature, the second layer is coated. After the second layer is cured at high temperature, the third layer is coated and bonded to the fiberglass cloth. After high temperature curing, flame-retardant silicone leather is obtained.

[0016] Preferably, the curing temperature for each layer of high-temperature curing is 100-180℃, and the curing time is 5-10 minutes. Preferably, the fiberglass base fabric in step (3) is flame-retardant fiberglass fabric.

[0017] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. This invention utilizes a 1:1 compound of nano-sized aluminum hydroxide and magnesium hydroxide, taking advantage of their synergistic high and low temperature flame-retardant effect. This not only significantly improves the flame-retardant rating of silicone leather, but also achieves higher flame-retardant efficiency and eliminates the risk of dripping compared to single flame retardant or micron-sized flame retardant systems. Simultaneously, the nano-sized flame retardant also has a reinforcing effect, bonding tightly with the silicone rubber matrix, effectively ensuring the material's mechanical properties and wear resistance, and avoiding the contradiction between flame retardancy and mechanical properties that traditional flame-retardant materials cannot simultaneously achieve.

[0018] 2. The flame-retardant silicone leather provided by this invention has a simple preparation process, convenient operation and control, stable quality, high production efficiency and finished product qualification rate, low production cost, and can be mass-produced industrially. Detailed Implementation

[0019] The technical solution of the present invention will be further explained and described below with reference to specific embodiments. It is worth noting that the following embodiments are only preferred embodiments of the present invention and should not be construed as limiting the present invention. The scope of protection of the present invention should be determined by the contents of the claims. Modifications and substitutions made by those skilled in the art to the technical solution of the present invention without creative effort all fall within the scope of protection of the present invention.

[0020] Example 1: A flame-retardant silicone leather comprises a fiberglass base fabric and a silicone coating, wherein the silicone coating comprises the following components in parts by weight: 1000 parts liquid silicone rubber, 300 parts nano-sized aluminum hydroxide, 300 parts nano-sized magnesium hydroxide, 100 parts hydrogen-containing vinyl silicone oil with a hydrogen content of 0.79%, 1.5 parts 1-acetylenecyclohexanol, 1.2 parts platinum catalyst, and 30 parts addition-cure silicone pigment.

[0021] The preparation method of the flame-retardant silicone leather includes the following steps: (1) Liquid organosilicon rubber, hydrogen-containing vinyl silicone oil, aluminum hydroxide, magnesium hydroxide, 1-acetylenecyclohexanol and addition-type silicone color paste are added to a planetary mixer and stirred for 10 minutes to mix evenly. Then, vacuum is applied to obtain a mixture. (2) Add platinum catalyst to the above mixture and stir for 30 minutes to mix evenly. Then, vacuum the mixture to obtain an organosilicon coating. (3) The above-mentioned silicone coating is applied to the release paper. The number of coating layers is 3, and the thickness of each layer is 0.1 mm. After the first layer is heated and cured, the second layer is applied. After the second layer is heated and cured, the third layer is applied and bonded to the flame-retardant fiberglass base cloth. The silicone leather is obtained by heating and curing for the third time. The curing temperature of the first layer and the second layer is 130℃ and the curing time is 6 min. The curing temperature of the third layer is 150℃ and the curing time is 6 min.

[0022] Example 2: A flame-retardant silicone leather comprises a fiberglass base fabric and a silicone coating, wherein the silicone coating comprises the following components in parts by weight: 1000 parts of liquid silicone rubber, 250 parts of nano-sized aluminum hydroxide, 250 parts of nano-sized magnesium hydroxide, 90 parts of hydrogen-containing vinyl silicone oil with a hydrogen content of 0.79%, 1.5 parts of 1-acetylenecyclohexanol, 1.2 parts of platinum catalyst, and 30 parts of addition-cure silicone pigment.

[0023] The preparation method of the flame-retardant silicone leather includes the following steps: (1) Liquid organosilicon rubber, hydrogen-containing vinyl silicone oil, aluminum hydroxide, magnesium hydroxide, 1-acetylenecyclohexanol and addition-type silicone color paste are added to a planetary mixer and stirred for 10 minutes to mix evenly. Then, vacuum is applied to obtain a mixture. (2) Add platinum catalyst to the above mixture and stir for 30 minutes to mix evenly. Then, vacuum the mixture to obtain an organosilicon coating. (3) The above-mentioned silicone coating is applied to the release paper. The number of coating layers is 3, and the thickness of each layer is 0.1 mm. After the first layer is heated and cured, the second layer is applied. After the second layer is heated and cured, the third layer is applied and bonded to the flame-retardant fiberglass base cloth. The silicone leather is obtained by heating and curing for the third time. The curing temperature of the first layer and the second layer is 130℃ and the curing time is 6 min. The curing temperature of the third layer is 150℃ and the curing time is 6 min.

[0024] Example 3: A flame-retardant silicone leather comprises a fiberglass base fabric and a silicone coating, wherein the silicone coating comprises the following components in parts by weight: 1000 parts liquid silicone rubber, 200 parts nano-sized aluminum hydroxide, 200 parts nano-sized magnesium hydroxide, 80 parts hydrogen-containing vinyl silicone oil with a hydrogen content of 0.79%, 1.5 parts 1-acetylenecyclohexanol, 1.2 parts platinum catalyst, and 30 parts addition-cure silicone pigment.

[0025] The preparation method of the flame-retardant silicone leather includes the following steps: (1) Liquid organosilicon rubber, hydrogen-containing vinyl silicone oil, aluminum hydroxide, magnesium hydroxide, 1-acetylenecyclohexanol and addition-type silicone color paste are added to a planetary mixer and stirred for 10 minutes to mix evenly. Then, vacuum is applied to obtain a mixture. (2) Add platinum catalyst to the above mixture and stir for 30 minutes to mix evenly. Then, vacuum the mixture to obtain an organosilicon coating. (3) The above-mentioned silicone coating is applied to the release paper. The number of coating layers is 3, and the thickness of each layer is 0.1 mm. After the first layer is heated and cured, the second layer is applied. After the second layer is heated and cured, the third layer is applied and bonded to the flame-retardant fiberglass base cloth. The silicone leather is obtained by heating and curing for the third time. The curing temperature of the first layer and the second layer is 130℃ and the curing time is 6 min. The curing temperature of the third layer is 150℃ and the curing time is 6 min.

[0026] Example 4: A flame-retardant silicone leather comprises a fiberglass base fabric and a silicone coating, wherein the silicone coating comprises the following components in parts by weight: 1000 parts of liquid silicone rubber, 350 parts of nano-sized aluminum hydroxide, 350 parts of nano-sized magnesium hydroxide, 100 parts of hydrogen-containing vinyl silicone oil with a hydrogen content of 0.79%, 1.5 parts of 1-acetylenecyclohexanol, 1.2 parts of platinum catalyst, and 30 parts of addition-cure silicone pigment.

[0027] The preparation method of the flame-retardant silicone leather includes the following steps: (1) Liquid organosilicon rubber, hydrogen-containing vinyl silicone oil, aluminum hydroxide, magnesium hydroxide, 1-acetylenecyclohexanol and addition-type silicone color paste are added to a planetary mixer and stirred for 10 minutes to mix evenly. Then, vacuum is applied to obtain a mixture. (2) Add platinum catalyst to the above mixture and stir for 30 minutes to mix evenly. Then, vacuum the mixture to obtain an organosilicon coating. (3) The above-mentioned silicone coating is applied to the release paper. The number of coating layers is 3, and the thickness of each layer is 0.1 mm. After the first layer is heated and cured, the second layer is applied. After the second layer is heated and cured, the third layer is applied and bonded to the flame-retardant fiberglass base cloth. The silicone leather is obtained by heating and curing for the third time. The curing temperature of the first layer and the second layer is 130℃ and the curing time is 6 min. The curing temperature of the third layer is 150℃ and the curing time is 6 min.

[0028] Comparative Example 1: The flame-retardant silicone leather components in this comparative example are the same as those in Example 2, except that aluminum hydroxide and magnesium hydroxide are both non-nanoscale, with a size in the micrometer range.

[0029] The preparation method is the same as in Example 2.

[0030] Comparative Example 2: The flame-retardant silicone leather component of this comparative example is the same as that of Example 2, except that it does not contain nano-sized aluminum hydroxide and nano-sized magnesium hydroxide, and contains 1.0 part of 1-acetylenecyclohexanol and 0.8 parts of platinum catalyst.

[0031] The preparation method is the same as in Example 2.

[0032] Comparative Example 3: The flame-retardant silicone leather component in this comparative example is the same as in Example 2, except that: both nano-sized aluminum hydroxide and nano-sized magnesium hydroxide are 150 parts.

[0033] The preparation method is the same as in Example 2.

[0034] Comparative Example 4: The flame-retardant silicone leather component in this comparative example is the same as in Example 2, except that: the amount of nano-sized aluminum hydroxide is 500 parts, and it does not contain nano-sized magnesium hydroxide.

[0035] The preparation method is the same as in Example 2.

[0036] Comparative Example 5: The flame-retardant silicone leather component in this comparative example is the same as in Example 2, except that it does not contain nano-sized aluminum hydroxide, and contains 500 parts of nano-sized magnesium hydroxide.

[0037] The preparation method is the same as in Example 2.

[0038] Comparative Example 6: The flame-retardant silicone leather components in this comparative example are the same as those in Example 2, except that: 100 parts of nano-sized aluminum hydroxide and 400 parts of nano-sized magnesium hydroxide are used.

[0039] The preparation method is the same as in Example 2.

[0040] Comparative Example 7: The flame-retardant silicone leather components in this comparative example are the same as those in Example 2, except that: the amount of nano-sized aluminum hydroxide is 200 parts and the amount of nano-sized magnesium hydroxide is 300 parts.

[0041] The preparation method is the same as in Example 2.

[0042] Comparative Example 8: The flame-retardant silicone leather components in this comparative example are the same as those in Example 2, except that: 400 parts of nano-sized aluminum hydroxide and 100 parts of nano-sized magnesium hydroxide are used.

[0043] The preparation method is the same as in Example 2.

[0044] Comparative Example 9: The flame-retardant silicone leather components in this comparative example are the same as those in Example 2, except that: the amount of nano-sized aluminum hydroxide is 300 parts and the amount of nano-sized magnesium hydroxide is 200 parts.

[0045] The preparation method is the same as in Example 2.

[0046] The performance of the silicone leather prepared in the above examples and comparative examples was tested respectively: (1) Flame retardant performance: The silicone leather was subjected to a 12s vertical burning test to evaluate its flame retardant performance. The flame retardant performance was evaluated according to the UL 94 test standard, with the grades being V0, V1, and V2. (2) Abrasion resistance: The Martindale abrasion resistance test method was used for testing. (3) Mechanical properties of the adhesive layer: Tensile strength (≥5MPa), elongation at break (≥90%), and tear strength (≥15kN / m) were examined.

[0047] The test results are shown in Table 1.

[0048] Table 1

[0049] As shown in Table 1, Examples 1-4 all achieved the UL94 V0 flame retardant rating, indicating that nano-sized aluminum hydroxide and magnesium hydroxide have a good synergistic flame retardant effect in the organosilicon coating. Among them, Examples 2 and 3 showed the best performance in terms of tensile strength, elongation at break, and tear strength. Example 3 (total flame retardant 400 parts) achieved mechanical properties of 6.0 MPa, 183%, and 19 kN / m, with the best overall performance. Although Example 4 met the flame retardant standard, the excessive flame retardant content caused the adhesive layer to become brittle, the tensile strength decreased to 4.4 MPa, the elongation at break was only 93%, and the abrasion resistance was less than 10,000 cycles, indicating that excessive filling would damage the toughness of the material.

[0050] Compared to Example 2, Comparative Example 1 used a micron-sized flame retardant. Although the flame retardancy was still V0, the mechanical properties decreased significantly, and the abrasion resistance was less than 10,000 cycles, indicating that nano-sizing is crucial for improving dispersibility and overall performance. Comparative Example 2 did not add a flame retardant and only contained a small amount of catalyst. Although the mechanical properties were excellent, the flame retardancy rating was only V2, which could not meet the flame retardancy requirements. In Comparative Examples 3-9, when the ratio of aluminum hydroxide to magnesium hydroxide was unbalanced or the total amount was too low, the flame retardancy could be maintained at V0 or V1, but the mechanical properties generally decreased. The tensile strength of Comparative Example 8 was only 2.7 MPa, and the tear strength was only 7.4 kN / m, indicating that aluminum hydroxide and magnesium hydroxide can only achieve the best synergistic effect when they are compounded in a 1:1 ratio.

[0051] In summary, this invention uses nano-grade aluminum hydroxide and magnesium hydroxide in a 1:1 ratio, with the total addition controlled within the range of 400-600 parts, and adds an appropriate amount of catalytic system, thereby achieving a balance between flame retardancy, mechanical properties and wear resistance.

[0052] The above embodiments are merely preferred technical solutions of the present invention and should not be considered as limitations on the present invention. The scope of protection of the present invention should be limited to the technical solutions described in the claims, including equivalent substitutions of the technical features described in the claims. That is, equivalent substitutions and improvements within this scope are also within the scope of protection of the present invention.

Claims

1. A flame-retardant silicone leather, characterized in that: It includes a fiberglass base fabric and an organosilicon coating. The organosilicon coating, by weight, includes 1000 parts of liquid organosilicon rubber, 80-100 parts of hydrogen-containing vinyl silicone oil, 0.8-2 parts of 1-acetylenecyclohexanol, 0.5-1 parts of platinum catalyst, 20-40 parts of color paste, 200-450 parts of aluminum hydroxide, and 150-400 parts of magnesium hydroxide.

2. The flame-retardant silicone leather according to claim 1, characterized in that: The hydrogen-containing vinyl silicone oil has a viscosity of 15-50 cSt and a hydrogen content of 0.36%-0.79%.

3. The flame-retardant silicone leather according to claim 1, characterized in that: The aluminum hydroxide and magnesium hydroxide both have nano-sized particles and a mass ratio of 1:

1.

4. The flame-retardant silicone leather according to claim 1, characterized in that: The amount of aluminum hydroxide and magnesium hydroxide added accounts for 40%-60% of the liquid silicone rubber.

5. The flame-retardant silicone leather according to claim 1, characterized in that: The colorant is an addition-type silica gel colorant.

6. The method for preparing a flame-retardant silicone leather according to any one of claims 1-5, characterized in that: Includes the following steps: (1) Liquid silicone rubber, hydrogen-containing vinyl silicone oil, aluminum hydroxide, magnesium hydroxide, 1-acetylenecyclohexanol and color paste are added to a planetary mixer and mixed evenly to obtain a mixture; (2) After adding platinum catalyst to the above mixture and stirring until homogeneous, an organosilicon coating is obtained; (3) The above-mentioned silicone coating is applied to the release paper, and then bonded to the fiberglass base cloth. After high-temperature curing, it becomes silicone leather.

7. The preparation method according to claim 6, characterized in that: The mixing time in step (1) is 10-20 minutes and vacuuming is performed at room temperature.

8. The preparation method according to claim 6, characterized in that: The mixing time in step (2) is 20-40 minutes and vacuuming is performed at room temperature.

9. The preparation method according to claim 6, characterized in that: In step (3), the number of silicone coating layers is 3. After the first layer is cured at high temperature, the second layer is coated. After the second layer is cured at high temperature, the third layer is coated and bonded to the fiberglass cloth. After high temperature curing, flame-retardant silicone leather is obtained.

10. The preparation method according to claim 9, characterized in that: The curing temperature for each layer is 100-180℃, and the curing time is 5-10 minutes.

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