Room-temperature vulcanized high-heat-resistance flame-retardant ceramic silicone rubber and preparation method thereof

Abstract

The invention belongs to the technical field of silicone rubber. The invention provides room-temperature vulcanization type high-heat-resistance flame-retardant ceramic silicone rubber. The high-temperature-resistant adhesive comprises the following components in parts by weight: 50-66 parts of a phenylene vinyl organic silicon polymer, 30-45 parts of a phenylene vinyl boron-containing organic silicon polymer, 4-8 parts of a cage-shaped organic silicon copolymer, 20-40 parts of a reinforcing filler, 10-20 parts of a ceramic filler, 2-4 parts of a platinum catalyst, 0.3-0.6 part of a cross-linking agent, 0.1-0.3 part of a cross-linking inhibitor and 1-4 parts of a processing aid. The peel strength of the prepared high-heat-resistance flame-retardant ceramic silicone rubber can reach 3.6 MPa, the elongation at break can reach 180%, the flame-retardant test passes the UL94V-0 standard, the heat insulation temperature can reach 500 DEG C or above, and the high-heat-resistance flame-retardant ceramic silicone rubber is vulcanized at normal temperature.

Description

Technical Field

[0001] This invention relates to the field of silicone rubber technology, and in particular to a room temperature vulcanizing type of high heat resistance and flame retardant ceramicized silicone rubber and its preparation method. Background Technology

[0002] Silicone rubber has a silicon-based structure as its main chain. Although silicon is chemically stable and not easily reduced or oxidized, its side chains contain a large number of carbon-containing groups. Therefore, modification and grafting of the side chains are necessary to impart better fire resistance and thermal insulation properties to silicon-based materials. In civilian applications, fire-resistant and thermal insulation layers are indispensable in the construction of high-rise buildings, hotels, large supermarkets, hospitals, and industrial insulated pipelines. In the military field, including nuclear power plants, launch vehicles, fighter jets, large warships, and aircraft carriers, there are also strict requirements for the thermal insulation and fire resistance of materials. In high-temperature operating environments, high-temperature resistant silicone rubber can ensure the safety of internal structural components such as wires and cables for a certain period of time, reducing casualties and loss of life and property, making it a reliable product for both military and civilian applications.

[0003] Therefore, researching and developing a room-temperature vulcanizing high heat-resistant and flame-retardant ceramicized silicone rubber and its preparation method can overcome the characteristic that ceramicized silicone rubber products in the existing technology require high-temperature vulcanization, and can also ensure the material's good thermal insulation performance and better application scenarios. Summary of the Invention

[0004] The purpose of this invention is to address the shortcomings of existing technologies by providing a room-temperature vulcanizing, high-heat-resistant, flame-retardant ceramicized silicone rubber and its preparation method. This addition-condensation hybrid flame-retardant ceramicized silicone rubber uses a single-component system, reacting at room temperature to form a structural layer. The three modified raw materials used give the silicone rubber excellent fire resistance and good flame retardancy with minimal degradation of material mechanical properties. Furthermore, it ensures excellent thermal insulation protection for components requiring protection even at high temperatures, thus expanding its application range.

[0005] To achieve the above-mentioned objectives, the present invention provides the following technical solution:

[0006] This invention provides a room temperature vulcanizing type of high heat resistance and flame retardant ceramicized silicone rubber, comprising the following components in parts by weight:

[0007] 50-66 parts of phenylene vinyl organosilicon polymer, 30-45 parts of phenylene vinyl boron-containing organosilicon polymer, 4-8 parts of cage-like organosilicon copolymer, 20-40 parts of reinforcing filler, 10-20 parts of ceramicized filler, 2-4 parts of platinum-based catalyst, 0.3-0.6 parts of crosslinking agent, 0.1-0.3 parts of crosslinking inhibitor, and 1-4 parts of processing aid.

[0008] Preferably, the phenylenevinyl silicone polymer has a number-average molecular weight of 400,000 to 800,000 and a structural formula of [structural formula would be inserted here]. The molar ratio of x, y, and z is 10–13:1:5–6.

[0009] Preferably, the phenylenevinyl boron-containing organosilicon polymer has a number-average molecular weight of 300,000 to 500,000 and a structural formula of [structural formula would be inserted here]. The molar ratio of x, y, and z is 28–31:1:18–20.

[0010] Preferably, the cage-like organosilicon copolymer has a number-average molecular weight of 800,000 to 1,000,000 and a structural formula of [structure not specified]. The molar ratio of x, y, and z is 12–14:1:10–12.

[0011] Preferably, the reinforcing filler is fumed silica.

[0012] The ceramicized filler is one or more of mica powder, wollastonite, magnesium silicate, and calcium silicate.

[0013] Preferably, the platinum-based catalyst is a cassiterite catalyst with a concentration of 1000–5000 ppm.

[0014] The crosslinking agent is one or more of benzoyl peroxide, 2,4-dichlorobenzoyl peroxide, and 2,5-dimethyl-2,5-di(tert-butylperoxide)hexane.

[0015] Preferably, the crosslinking inhibitor is an alkynyl alcohol and / or a polyvinyl silicone oil;

[0016] The processing aid is one or more of zinc oxide, titanium dioxide, zinc stearate, and calcium stearate.

[0017] The present invention also provides a method for preparing the room temperature vulcanizing high heat-resistant and flame-retardant ceramicized silicone rubber, comprising the following steps:

[0018] 1) The phenylene vinyl organosilicon polymer, the phenylene vinyl boron-containing organosilicon polymer, and the cage-like organosilicon copolymer were plasticized on a rubber two-roll mill to obtain an organosilicon rubber compound.

[0019] 3) The silicone rubber compound, reinforcing filler, ceramicized filler and crosslinking inhibitor are mixed to obtain silicone rubber composite material;

[0020] 3) After mixing the silicone rubber composite material, platinum catalyst, crosslinking agent and processing aid, stop the mixing, press into sheets, and wait for the product to naturally vulcanize to obtain room temperature vulcanizing type high heat resistance and flame retardant ceramicized silicone rubber.

[0021] Preferably, the plasticizing speed in step 1) is 120-130 r / min, the plasticizing temperature is 20-30℃, and the plasticizing time is 20-30 min.

[0022] Preferably, the mixing temperature in step 2) is 15-30°C, the mixing time is 1-2 min, and the mixing speed is 100-130 r / min;

[0023] The mixing temperature in step 3) is 15-30℃, the mixing time is 1-2 min, and the mixing speed is 100-130 r / min;

[0024] Step 3) The pressure of the tablet is 15-25 MPa, and the thickness of the tablet is 0.5-1.5 mm.

[0025] The beneficial effects of this invention are as follows:

[0026] The high heat-resistant and flame-retardant ceramicized silicone rubber prepared by this invention has a peel strength of up to 3.6 MPa, an elongation at break of up to 180%, passes the UL94 V-0 standard for flame retardancy testing, and has a heat insulation temperature of up to 500℃ and can be vulcanized at room temperature. Detailed Implementation

[0027] This invention provides a room temperature vulcanizing type of high heat resistance and flame retardant ceramicized silicone rubber, comprising the following components in parts by weight:

[0028] 50-66 parts of phenylene vinyl organosilicon polymer, 30-45 parts of phenylene vinyl boron-containing organosilicon polymer, 4-8 parts of cage-like organosilicon copolymer, 20-40 parts of reinforcing filler, 10-20 parts of ceramicized filler, 2-4 parts of platinum-based catalyst, 0.3-0.6 parts of crosslinking agent, 0.1-0.3 parts of crosslinking inhibitor, and 1-4 parts of processing aid.

[0029] The room temperature vulcanizing high heat-resistant and flame-retardant ceramicized silicone rubber of the present invention comprises 50 to 66 parts of phenylene vinyl organosilicon polymer, preferably 52 to 63 parts, more preferably 54 to 60 parts, and more preferably 55 parts.

[0030] In this invention, the number-average molecular weight of the phenylenevinyl silicone polymer is preferably 400,000 to 800,000, and the preferred structural formula is... The molar ratio of x, y and z is preferably 10-13:1:5-6, and more preferably 12:1:5.

[0031] The room temperature vulcanizing high heat-resistant and flame-retardant ceramicized silicone rubber of the present invention comprises 30 to 45 parts of phenylene vinyl boron-containing organosilicon polymer, preferably 32 to 40 parts, more preferably 34 to 36 parts, and more preferably 35 parts.

[0032] In this invention, the number-average molecular weight of the phenylenevinyl boron-containing organosilicon polymer is preferably 300,000 to 500,000, and the preferred structural formula is... The molar ratio of x, y and z is preferably 28-31:1:18-20, and more preferably 30:1:20.

[0033] The room temperature vulcanizing high heat-resistant and flame-retardant ceramicized silicone rubber of the present invention comprises 4 to 8 parts of cage-like organosilicon copolymer, preferably 5 to 7 parts, more preferably 5.5 to 6.5 parts, and more preferably 6 parts.

[0034] In this invention, the number-average molecular weight of the cage-like organosilicon copolymer is preferably 800,000 to 1,000,000, and the preferred structural formula is... The molar ratio of x, y and z is preferably 12-14:1:10-12, and more preferably 13:1:11.

[0035] The room temperature vulcanizing high heat-resistant and flame-retardant ceramicized silicone rubber of the present invention contains 20 to 40 parts of reinforcing filler, preferably 24 to 36 parts, more preferably 28 to 32 parts, and more preferably 30 parts.

[0036] In this invention, the reinforcing filler is preferably fumed silica.

[0037] The room temperature vulcanizing high heat-resistant and flame-retardant ceramicized silicone rubber of the present invention contains 10 to 20 parts of ceramicized filler, preferably 12 to 18 parts, more preferably 14 to 16 parts, and even more preferably 15 parts.

[0038] In this invention, the ceramicized filler is preferably one or more of mica powder, wollastonite, magnesium silicate, and calcium silicate.

[0039] The room temperature vulcanizing high heat-resistant and flame-retardant ceramicized silicone rubber of the present invention contains 2 to 4 parts of platinum-based catalyst, preferably 2.4 to 3.6 parts, more preferably 2.8 to 3.2 parts, and more preferably 3 parts.

[0040] In this invention, the platinum-based catalyst is preferably a caster catalyst, and the concentration of the caster catalyst is preferably 1000-5000 ppm, more preferably 2000-4000 ppm, and even more preferably 3000 ppm.

[0041] The room temperature vulcanizing high heat-resistant and flame-retardant ceramicized silicone rubber of the present invention contains 0.3 to 0.6 parts of crosslinking agent, preferably 0.35 to 0.55 parts, more preferably 0.4 to 0.5 parts, and more preferably 0.45 parts.

[0042] In this invention, the crosslinking agent is preferably one or more of benzoyl peroxide, 2,4-dichlorobenzoyl peroxide, and 2,5-dimethyl-2,5-di(tert-butylperoxide)hexane.

[0043] The room temperature vulcanizing high heat-resistant and flame-retardant ceramicized silicone rubber of the present invention contains 0.1 to 0.3 parts of crosslinking inhibitor, preferably 0.15 to 0.25 parts, more preferably 0.18 to 0.22 parts, and more preferably 0.2 parts.

[0044] In this invention, the crosslinking inhibitor is preferably alkynyl alcohol and / or polyvinyl silicone oil.

[0045] The room temperature vulcanizing high heat-resistant and flame-retardant ceramicized silicone rubber of the present invention contains 1 to 4 parts of processing aids, preferably 1.5 to 3.5 parts, more preferably 2 to 3 parts, and more preferably 2.5 parts.

[0046] In this invention, the processing aid is preferably one or more of zinc oxide, titanium dioxide, zinc stearate, and calcium stearate.

[0047] The present invention also provides a method for preparing the room temperature vulcanizing high heat-resistant and flame-retardant ceramicized silicone rubber, comprising the following steps:

[0048] 1) The phenylene vinyl organosilicon polymer, the phenylene vinyl boron-containing organosilicon polymer, and the cage-like organosilicon copolymer were plasticized on a rubber two-roll mill to obtain an organosilicon rubber compound.

[0049] 2) The silicone rubber compound, reinforcing filler, ceramicized filler and crosslinking inhibitor are mixed to obtain silicone rubber composite material;

[0050] 3) After mixing the silicone rubber composite material, platinum catalyst, crosslinking agent and processing aid, stop the mixing, press into sheets, and wait for the product to naturally vulcanize to obtain room temperature vulcanizing type high heat resistance and flame retardant ceramicized silicone rubber.

[0051] In this invention, the plasticizing speed in step 1) is preferably 120-130 r / min, more preferably 124-126 r / min, and even more preferably 125 r / min; the plasticizing temperature is preferably 20-30°C, more preferably 25°C; and the plasticizing time is preferably 20-30 min, more preferably 24-26 min, and even more preferably 25 min.

[0052] In this invention, the mixing temperature in step 2) is preferably 15-30°C, more preferably 18-25°C, and even more preferably 20°C; the mixing time is preferably 1-2 min, more preferably 1.4-1.6 min, and even more preferably 1.5 min; the mixing speed is preferably 100-130 r / min, more preferably 110-120 r / min, and even more preferably 115 r / min.

[0053] The mixing temperature in step 3) is preferably 15-30°C, more preferably 18-25°C, and even more preferably 20°C; the mixing time is preferably 1-2 min, more preferably 1.4-1.6 min, and even more preferably 1.5 min; the mixing speed is preferably 100-130 r / min, more preferably 110-120 r / min, and even more preferably 115 r / min.

[0054] The pressure of the tablet compression in step 3) is preferably 15-25 MPa, more preferably 20 MPa, and the thickness of the tablet is preferably 0.5-1.5 mm, more preferably 1 mm.

[0055] The technical solutions provided by the present invention will be described in detail below with reference to the embodiments, but they should not be construed as limiting the scope of protection of the present invention.

[0056] 1. The preparation process of the phenylenevinyl silicone polymer used in the embodiments of the present invention is as follows:

[0057] 1) Add 1,4-bis(dimethylhydroxysilyl)benzene to o-xylene, heat to 110°C, and then start mechanical stirring to completely dissolve it at a speed of 200 rpm to form a solution with a mass fraction of 40%.

[0058] 2) Add isooctanoate of hexylamine to the solution, the mass of isooctanoate of hexylamine being 1% of the mass of 1,4-bis(dimethylhydroxysilyl)benzene. Heat to a slight boil, assemble an oil-water separator, reflux and dehydrate for 6 hours, and then remove o-xylene by vacuum distillation at 120°C to obtain a condensation polymer of 1,4-bis(dimethylhydroxysilyl)benzene with a number average molecular weight of approximately 150,000.

[0059] 3) 5g of a 25% tetramethylammonium hydroxide methanol solution was placed in a three-necked flask and the methanol was removed by vacuum distillation at 80℃ and 20-40Pa to obtain a white solid. Then, nitrogen gas was introduced and the solid was sealed for later use.

[0060] 4) Add 34.4 g of tetramethyltetravinylcyclotetrasiloxane and 30 g of anhydrous toluene to the white solid. Then stir the mixture at 85 °C for 2 h. After that, remove the toluene and the small amount of water generated by vacuum distillation at 20-80 Pa. Purge with nitrogen and add 30 g of anhydrous toluene. Repeat the process every 1 h. After 8 h, remove the toluene and the small amount of water generated by vacuum distillation at 20-80 Pa to obtain a slightly viscous, translucent liquid.

[0061] 5) Take 0.5g of the slightly viscous, translucent liquid obtained in step 4), 30g of tetramethyltetravinylcyclotetrasiloxane, 63g of octamethylcyclotetrasiloxane, 0.035g of hexamethyldisiloxane, and 31g of the condensation polymer of 1,4-bis(dimethylhydroxysilyl)benzene. Then, stir the mixture at 95℃ under a nitrogen atmosphere for 6 hours, and then stir it at 160℃ and 50-100Pa for 2 hours at a stirring speed of 200 rpm. After that, cool the mixture to room temperature, slowly open the flask, and extract the low molecular weight polymer with isopropanol at a mass ratio of 3:1. Stir the mixture at room temperature for 1 hour at a stirring speed of 200 rpm, pour it into a separatory funnel, let it stand for 30 minutes, remove the supernatant, and repeat this process three times. Take out the product from the flask, and distill the remaining isopropanol under reduced pressure at 45℃.

[0062] 6) The product was dried in a vacuum drying oven at 60℃ and 20-40 Pa for 4 hours to obtain a phenylenevinyl silicone polymer. The number-average molecular weight of the phenylenevinyl silicone polymer was approximately 600,000, and its structural formula was as follows: Where x, y, and z are 4050, 330, and 1740, respectively.

[0063] 2. The preparation process of the phenylenevinyl boron-containing organosilicon polymer used in the embodiments of the present invention is as follows:

[0064] 1) Diphenyl dichlorosilane and boric acid were added to anhydrous n-butyl ether in a molar ratio of 1:1. The mixture was then heated to form a 30% (w / w) transparent solution under a nitrogen atmosphere and a stirring speed of 200 rpm at 100 °C. The n-butyl ether was removed under vacuum of 50–100 Pa. The reaction was continued at 100 °C for 0.5 h while maintaining the vacuum. The temperature was then lowered to 80 °C and dried under vacuum of 20–40 Pa for 24 h. The temperature was then lowered to room temperature, and hydroquinone and o-xylene were added in the same molar amount as diphenyl dichlorosilane. The mixture was stirred at 300 rpm to form a 30% (w / w) solution. The temperature was raised to 150 °C, and an oil-water separator was installed. The mixture was stirred and refluxed at 200 rpm for 7 h to remove water. The reaction was then carried out under vacuum distillation at 120 °C and 50–100 Pa to remove o-xylene, resulting in a hydroxyl-terminated phenylene boron-containing organosilicon polymer with a number average molecular weight of 50,000.

[0065] 2) 5g of a 25% tetramethylammonium hydroxide methanol solution was placed in a three-necked flask, and then the methanol was removed by vacuum distillation at 80℃ and 20-40Pa to obtain a white solid, which was then sealed with nitrogen for later use.

[0066] 3) Add 34.4 g of tetramethyltetravinylcyclotetrasiloxane and 30 g of anhydrous toluene to the white solid, stir at 85 °C for 2 h at a stirring speed of 200 rpm, then remove toluene and a small amount of water by vacuum distillation at 20-40 Pa, purge with nitrogen, add 30 g of anhydrous toluene, repeat the process every 1 h, and after 8 h, remove toluene and a small amount of water by vacuum distillation at 20-40 Pa to obtain a slightly viscous, translucent liquid.

[0067] 4) Take 0.5g of the slightly viscous, translucent liquid obtained in step 3), 30g of tetramethyltetravinylcyclotetrasiloxane, 42g of octamethylcyclotetrasiloxane, 0.035g of hexamethyldisiloxane, and 11g of terminal hydroxyphenylene boron-containing organosilicon polymer. Then, stir the mixture at 95℃ and nitrogen atmosphere for 6h at a stirring speed of 200rpm. After that, raise the temperature to 160℃ and stir at 50-100Pa for 2h. Cool to room temperature, slowly open the flask, and extract the low molecular weight polymer with isopropanol at a mass ratio of 3:1 to the product. Then, stir at room temperature for 1h at a stirring speed of 300rpm. Pour the mixture into a separatory funnel, let it stand for 30min, remove the supernatant, and repeat this process three times. Take out the product from the flask, and distill the remaining isopropanol under reduced pressure at 45℃.

[0068] 5) The product was dried in a vacuum drying oven at 50℃ and 20–40 Pa for 4 hours to obtain a phenylenevinyl boron-containing organosilicon polymer. The number-average molecular weight of the phenylenevinyl boron-containing organosilicon polymer was approximately 400,000, and its structural formula was as follows: Where x, y, and z are 2700, 92, and 1745, respectively.

[0069] 3. The preparation process of the cage-like organosilicon copolymer used in the embodiments of the present invention is as follows:

[0070] 1) Dissolve hexaphenyl dihydroxy POSS in o-xylene in a three-necked flask to form a 30% (w / w) solution. Then heat the solution to 150°C, assemble an oil-water separator, stir and reflux at 200 rpm for 7 h to remove water, and then remove o-xylene by vacuum distillation at 120°C and 50-100 Pa to obtain a terminal hydroxyl POSS polymer with a number average molecular weight of 300,000.

[0071] 2) Put 5g of 25% tetramethylammonium hydroxide methanol solution into a three-necked flask, then remove the methanol by vacuum distillation at 80℃ to form a white solid, and seal it with nitrogen for later use.

[0072] 3) Add 34.4 g of tetramethyltetravinylcyclotetrasiloxane and 30 g of anhydrous toluene to the white solid in step 2). Stir at 85 °C for 2 h at a stirring speed of 200 rpm. Then, remove toluene and a small amount of water by vacuum distillation at 20-40 Pa. Purge with nitrogen and add another 30 g of anhydrous toluene. Repeat this process every 1 h. After 8 h, remove toluene and a small amount of water by vacuum distillation at 20-40 Pa to obtain a slightly viscous, translucent liquid.

[0073] 4) Take 0.5g of the slightly viscous, translucent liquid obtained in step 3), 60g of tetramethyltetraethylenecyclotetrasiloxane, 62g of octamethylcyclotetrasiloxane, 0.033g of hexamethyldisiloxane, and 61g of terminal hydroxyl POSS polymer. Stir the mixture at 95℃ and a nitrogen atmosphere for 7 hours at a stirring speed of 300 rpm. Then, raise the temperature to 160℃ and stir for 2 hours under a negative pressure of 50-100 Pa at a stirring speed of 200 rpm. After that, lower the temperature to room temperature, slowly open the flask, and extract the low molecular weight polymer with isopropanol at a mass ratio of 3:1. Stir at 200 rpm for 1 hour at room temperature, pour the mixture into a separatory funnel, let it stand for 30 minutes, remove the supernatant, and repeat this process three times. The product was removed from the flask, and the remaining isopropanol was distilled under reduced pressure at 45°C and 20–40 Pa, followed by vacuum drying at 50–60°C and 20–40 Pa for 4 hours to obtain a cage-like organosilicon copolymer. The number-average molecular weight of the cage-like organosilicon copolymer was approximately 870,000, and its structural formula was as follows: Where x, y, and z are 4050, 310, and 3488, respectively.

[0074] 4. The fumed silica used in the embodiments of the present invention is hydrophobic amorphous fumed silica HDK H15 or HDK H20 produced by Wacker Chemie AG, Germany.

[0075] Example 1

[0076] 50g of phenylene vinyl silicone polymer, 42g of phenylene vinyl boron-containing silicone polymer and 8g of cage-shaped silicone copolymer were plasticized on a rubber two-roll mill at a speed of 125r / min, a temperature of 25℃ and a time of 25min to obtain silicone rubber compound.

[0077] The silicone rubber compound, 25g HDK H15, 6g mica powder, 8g wollastonite, 3g magnesium silicate and 0.2g 1-ethynylcyclohexanol were mixed at a temperature of 25℃ for 2 minutes and a speed of 130 r / min to obtain the silicone rubber composite material.

[0078] The silicone rubber composite material, 2g of 2000ppm castor catalyst, 0.3g of benzoyl peroxide, 0.5g of titanium dioxide and 1g of zinc stearate were mixed at 15℃ for 2 minutes at a speed of 130r / min. The mixing was then stopped, and the product was pressed into sheets at a pressure of 15MPa and a thickness of 1.5mm. The product was allowed to naturally vulcanize to obtain a room temperature vulcanizing type of high heat resistance and flame retardant ceramicized silicone rubber.

[0079] Example 2

[0080] 60g of phenylene vinyl silicone polymer, 45g of phenylene vinyl boron-containing silicone polymer and 5g of cage-shaped silicone copolymer were plasticized on a rubber two-roll mill at a speed of 120r / min, a temperature of 20℃ and a time of 30min to obtain silicone rubber compound.

[0081] The silicone rubber compound, 25g HDK H2O, 6g mica powder, 8g wollastonite, 3g magnesium silicate and 0.25g 1-ethynylcyclohexanol were mixed at a temperature of 15℃ for 1 min and a speed of 120 r / min to obtain the silicone rubber composite material.

[0082] The silicone rubber composite material, 3g of 1000ppm castor catalyst, 0.5g of 2,4-dichlorobenzoyl peroxide, 0.5g of titanium dioxide, and 1g of zinc stearate were mixed at 30℃ for 1 minute at a speed of 100r / min. The mixing was then stopped, and the product was pressed into sheets at a pressure of 25MPa and a thickness of 0.5mm. The product was allowed to naturally vulcanize to obtain a room temperature vulcanizing type of high heat resistance and flame retardant ceramicized silicone rubber.

[0083] Example 3

[0084] 58g of phenylene vinyl silicone polymer, 45g of phenylene vinyl boron-containing silicone polymer and 4g of cage-shaped silicone copolymer were plasticized on a rubber two-roll mill at a speed of 130r / min, a temperature of 30℃ and a time of 20min to obtain silicone rubber compound.

[0085] The silicone rubber compound, 20g HDK H15, 14g wollastonite, 6g calcium silicate and 0.3g 1-ethynylcyclohexanol were mixed at a temperature of 30℃ for 1.5min and a speed of 100r / min to obtain the silicone rubber composite material.

[0086] The silicone rubber composite material, 4g of 5000ppm castor catalyst, 0.6g of 2,5-dimethyl-2,5-di(tert-butylperoxide)hexane, 0.5g of titanium dioxide and 1g of calcium stearate were mixed at 25℃ for 1.5min at a speed of 120r / min. The mixing was then stopped, and the product was pressed into sheets at a pressure of 20MPa and a thickness of 1mm. The product was allowed to naturally vulcanize to obtain a room temperature vulcanizing type of high heat resistance and flame retardant ceramicized silicone rubber.

[0087] Example 4

[0088] The method is basically the same as in Example 1, except that the amount of phenylene vinyl silicone polymer is modified to 66g, the amount of phenylene vinyl boron silicone polymer is modified to 30g, the amount of fumed silica is modified to 40g, and the amount of wollastonite is modified to 1g.

[0089] The room temperature vulcanized high heat-resistant and flame-retardant ceramicized silicone rubbers prepared in Examples 1-4 were subjected to performance tests, and the test results are shown in Table 1.

[0090] Table 1. Performance test results of silicone rubbers prepared in different embodiments.

[0091]

[0092] As shown in Table 1, the peel strength of the room temperature vulcanizing high heat resistance and flame retardant ceramicized silicone rubber prepared by this invention is all above 3.0 MPa, the flame retardant test all passed the UL94 V-0 standard, and the heat insulation temperature reaches above 500℃. The room temperature vulcanization effect is significant.

[0093] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A room temperature vulcanizing, high heat-resistant, flame-retardant, ceramicized silicone rubber, characterized in that, The components comprise the following parts by weight: 50-66 parts of phenylene vinyl organosilicon polymer, 30-45 parts of phenylene vinyl boron-containing organosilicon polymer, 4-8 parts of cage-like organosilicon copolymer, 20-40 parts of reinforcing filler, 10-20 parts of ceramicized filler, 2-4 parts of platinum-based catalyst, 0.3-0.6 parts of crosslinking agent, 0.1-0.3 parts of crosslinking inhibitor, and 1-4 parts of processing aid.

2. The room temperature vulcanizing, high heat-resistant, flame-retardant ceramicized silicone rubber according to claim 1, characterized in that, The number-average molecular weight of the phenylenevinyl silicone polymer is 400,000 to 800,000, and its structural formula is as follows: The molar ratio of x, y, and z is 10–13:1:5–6.

3. The room temperature vulcanizing, high heat-resistant, flame-retardant, ceramicized silicone rubber according to claim 1 or 2, characterized in that, The phenylenevinyl boron-containing organosilicon polymer has a number-average molecular weight of 300,000 to 500,000 and a structural formula of [structural formula would be inserted here]. The molar ratio of x, y, and z is 28–31:1:18–20.

4. The room temperature vulcanizing, high heat-resistant, flame-retardant ceramicized silicone rubber according to claim 3, characterized in that, The cage-like organosilicon copolymer has a number-average molecular weight of 800,000 to 1,000,000 and its structural formula is as follows: The molar ratio of x, y, and z is 12–14:1:10–12.

5. The room temperature vulcanizing, high heat-resistant, flame-retardant, ceramicized silicone rubber according to claim 4, characterized in that, The reinforcing filler is fumed silica; The ceramicized filler is one or more of mica powder, wollastonite, magnesium silicate, and calcium silicate.

6. The room temperature vulcanizing, high heat-resistant, flame-retardant, ceramicized silicone rubber according to claim 4 or 5, characterized in that, The platinum-based catalyst is a cassiterite catalyst, and the concentration of the cassiterite catalyst is 1000-5000 ppm; The crosslinking agent is one or more of benzoyl peroxide, 2,4-dichlorobenzoyl peroxide, and 2,5-dimethyl-2,5-di(tert-butylperoxide)hexane.

7. The room temperature vulcanizing, high heat-resistant, flame-retardant, ceramicized silicone rubber according to claim 6, characterized in that, The crosslinking inhibitor is an alkynyl alcohol and / or a polyvinyl silicone oil; The processing aid is one or more of zinc oxide, titanium dioxide, zinc stearate, and calcium stearate.

8. The method for preparing room temperature vulcanizing high heat-resistant and flame-retardant ceramicized silicone rubber according to any one of claims 1 to 7, characterized in that, It includes the following steps: 1) The phenylene vinyl organosilicon polymer, the phenylene vinyl boron-containing organosilicon polymer, and the cage-like organosilicon copolymer were plasticized on a rubber two-roll mill to obtain an organosilicon rubber compound. 2) The silicone rubber compound, reinforcing filler, ceramicized filler and crosslinking inhibitor are mixed to obtain silicone rubber composite material; 3) After mixing the silicone rubber composite material, platinum catalyst, crosslinking agent and processing aid, stop the mixing, press into sheets, and wait for the product to naturally vulcanize to obtain room temperature vulcanizing type high heat resistance and flame retardant ceramicized silicone rubber.

9. The preparation method according to claim 8, characterized in that, Step 1) The plasticizing speed is 120-130 r / min, the plasticizing temperature is 20-30℃, and the plasticizing time is 20-30 min.

10. The preparation method according to claim 9, characterized in that, The mixing temperature in step 2) is 15-30℃, the mixing time is 1-2 min, and the mixing speed is 100-130 r / min; Step 3) The mixing temperature is 15-30℃, the mixing time is 1-2 min, and the mixing speed is 100-130 r / min; Step 3) The pressure of the tablet is 15-25 MPa, and the thickness of the tablet is 0.5-1.5 mm.

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