A flame retardant and ultra-high temperature resistant ceramic silicone rubber material and preparation method thereof

Abstract

The invention relates to the field of ceramic silicone rubber, and in particular to a flame retardant and ultra-high temperature resistant ceramic silicone rubber material and a preparation method thereof. The ceramic silicone rubber material comprises the following raw materials in parts by weight: 40-70 parts of silicone oil, 10-15 parts of reinforcing fillers, 40-50 parts of ceramic fillers, 15-25 parts of composite additives, 10-20 parts of structure control agents, and 0.15-0.4 parts of inhibitors. By adding the composite additives, the problem that the flame retardant and high temperature resistance of the existing ceramic silicone rubber material decrease due to the addition of flux is solved, and the impact resistance of the ceramic silicone rubber material after ceramicization is improved, so that the ceramic silicone rubber material can still maintain a certain working ability when a fire occurs.

Description

Technical Field

[0001] The invention relates to the field of ceramic silicone rubber, and in particular to a flame retardant and ultra-high temperature resistant ceramic silicone rubber material and a preparation method thereof. Background Art

[0002] Ceramic silicone rubber composite material is a new type of polymer refractory material. Different from composite materials made of traditional flame retardant materials, ceramic silicone rubber composite materials have fireproof and fireproof functions in addition to traditional flame retardant. The main components that affect the ceramic properties are flux and ceramic filler. The ceramic filler mainly includes mica, kaolin, silicate, wollastonite, etc. The flux is generally glass powder, boron-containing compounds or alkali metal compounds, etc., or the ceramic powder itself contains flux components such as alkali metal oxides.

[0003] However, currently common fluxes all have the problem of supporting combustion or reducing the heat resistance of polymers, resulting in insufficient flame retardancy of ceramic silicone rubber. At the same time, in order to ensure that the ceramic silicone rubber material can still maintain a certain working ability when a fire occurs, it is necessary to improve its impact resistance after ceramicization. Summary of the invention

[0004] The purpose of the present invention is to provide a flame retardant and ultra-high temperature resistant ceramic silicone rubber material and a preparation method thereof. By adding a composite additive, the problem of the existing ceramic silicone rubber material having reduced flame retardancy and high temperature resistance due to the addition of flux is solved, and at the same time, the impact resistance of the ceramic silicone rubber material is improved, so that the material can still maintain a certain working ability when a fire occurs.

[0005] The purpose of the present invention can be achieved by the following technical scheme: A method for preparing a flame-retardant and ultra-high temperature resistant ceramic silicone rubber material, comprising the following steps: Step S1: weighing the following raw materials in parts by weight: 40-70 parts of silicone oil, 10-15 parts of reinforcing filler, 40-50 parts of ceramic filler, 15-25 parts of composite additive, 10-20 parts of structure control agent, and 0.15-0.4 parts of inhibitor;

[0006] Step S2: Silicone oil, reinforcing filler, ceramic filler, composite additive, structure control agent and inhibitor are mixed and added into a planetary mixer, stirred for 30 minutes at a speed of 50 rpm and room temperature, and then sent to a calendering line, cured for 5 minutes at a temperature of 120-140° C., to obtain a flame-retardant and ultra-high temperature resistant ceramic silicone rubber material;

[0007] The composite auxiliary agent is prepared by the following steps:

[0008] Step A1: hexagonal boron nitride, urea and deionized water are mixed and added to a ball mill, and ball milled for 8-10 hours at a rotation speed of 800 rpm and room temperature to obtain amino boron nitride; amino boron nitride, paraformylbenzoic acid and ethanol are mixed, and anhydrous acetic acid is added under argon protection at a stirring rate of 100-120 rpm and a temperature of 80°C, and the reaction is carried out for 3-4 hours to obtain a precursor 1;

[0009] The dosage ratio of hexagonal boron nitride, urea and deionized water is 2-3 g: 100 g: 180-200 mL, and the dosage ratio of amination boron nitride, p-formylbenzoic acid and anhydrous acetic acid is 0.15-0.18 g: 0.075-0.08 mol: 3-4 mL;

[0010] During the reaction, under the action of ball milling, the hexagonal boron nitride flakes are continuously peeled off with the assistance of urea, and at the same time, urea reacts chemically with the BN bond of boron nitride, thereby introducing an amino group to obtain amino boron nitride. The amino group in the amino boron nitride reacts with the aldehyde group in p-formylbenzoic acid to form an imine structure, thereby obtaining precursor 1.

[0011] Step A2: Precursor 1, 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide and anhydrous ethanol are mixed and ultrasonically dispersed for 15 minutes, and reacted for 4-6 hours at room temperature at a stirring rate of 100-120 rpm to obtain precursor 2. Precursor 2, mono-6-O-amino-β-cyclodextrin and deionized water are mixed and ultrasonically dispersed for 10 minutes, sodium carbonate solution is added to adjust the pH to 8, and then 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide and N-hydroxysuccinimide are added at a stirring rate of 100-120 rpm and a temperature of 35° C., and the reaction is carried out for 4-6 hours to obtain precursor 3;

[0012] The amount ratio of precursor 1, 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide and anhydrous ethanol is 0.18-0.2g: 0.03-0.04mol: 80-90mL, the mass fraction of the sodium carbonate solution is 10%, and the amount ratio of precursor 2, mono-6-O-amino-β-cyclodextrin, 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide and N-hydroxysuccinimide is 0.18-0.2g: 2-2.4g: 0.003mol: 0.003mol;

[0013] During the reaction, the imine group in the precursor 1 reacts with the PH bond in 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide to obtain the precursor 2, and then under the action of 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide and N-hydroxysuccinimide, the carboxyl group in the precursor 2 reacts with the amino group in mono-6-O-amino-β-cyclodextrin to form an amide group to obtain the precursor 3;

[0014] Step A3: Precursor 3 and dichloromethane were mixed and ultrasonically dispersed for 20 minutes, and the modified boron-containing silicone oil was added under stirring at a stirring rate of 120-160 rpm and a temperature of 40° C., and stirred for 3-4 hours to obtain a composite auxiliary agent;

[0015] The ratio of precursor 3, dichloromethane and modified boron-containing silicone oil is 0.4-0.48g: 60-80mL: 20-22g;

[0016] During the reaction, the precursor 3 is compounded in the modified boron-containing silicone oil through the host-guest inclusion reaction between the ferrocene structure in the modified boron-containing silicone oil and the cyclodextrin structure in the precursor 3, thereby obtaining a composite auxiliary agent;

[0017] The modified boron-containing silicone oil is prepared by the following steps:

[0018] Step B1: Mix ferrocenylboric acid and diethylene glycol dimethyl ether, stir at a stirring rate of 60-80 rpm and a temperature of 60° C., add concentrated sulfuric acid and dimethyldichlorosilane, react for 2-2.5 hours, then add methyldichlorosilane, continue to react for 1.5-2 hours, wash until neutral, and dry to obtain terminal hydrogen-containing boron silicone oil;

[0019] The mass fraction of concentrated sulfuric acid is 60%, and the dosage ratio of ferrocenylboric acid, diethylene glycol dimethyl ether, concentrated sulfuric acid, dimethyldichlorosilane and methyldichlorosilane is 0.05mol:400-500mL:100-120mL:0.4-0.5mol:0.05mol;

[0020] During the reaction, dimethyldichlorosilane and methyldichlorosilane will be hydrolyzed in water, so that the chlorine group is converted into a hydroxyl group. Then, concentrated sulfuric acid is used as a catalyst, and the hydrolyzed dimethyldichlorosilane is copolymerized with the boric acid group in ferrocenylboric acid, and then the hydrolyzed methyldichlorosilane is used to cap the end to obtain hydrogen-terminated boron-containing silicone oil.

[0021] Step B2: salicylaldehyde, (3-aminopropyl)triethoxysilane and anhydrous ethanol are mixed, stirred at a stirring rate of 80-100 rpm and a temperature of 80° C. under nitrogen protection, and anhydrous acetic acid is added for reaction for 2-3 hours to obtain intermediate a; intermediate a, platinum acetate and dichloromethane are mixed, stirred at a stirring rate of 40-60 rpm and room temperature for reaction for 24 hours to obtain intermediate b;

[0022] The amount ratio of salicylaldehyde, (3-aminopropyl) triethoxysilane and anhydrous acetic acid is 0.02-0.03 mol: 0.022-0.032 mol: 0.8-1 mL, and the amount ratio of intermediate a, platinum acetate and dichloromethane is 0.02-0.03 mol: 0.1-0.11 g: 20-25 mL;

[0023] During the reaction, the aldehyde group in salicylaldehyde reacts with the amino group in (3-aminopropyl)triethoxysilane to form a Schiff base structure to obtain an intermediate a, and then the Schiff base structure in the intermediate a is complexed with platinum acetate to obtain a complex platinum intermediate b;

[0024] Step B3: Mix allyl alcohol, butyl phthalate and toluene, stir at a stirring rate of 80-100 rpm and a temperature of 80°C, add intermediate b, and react for 2-3 hours to obtain intermediate c, mix intermediate c, hydrogen-terminated boron-containing silicone oil and Castaplatin catalyst, and react for 4-6 hours at a stirring rate of 50-60 rpm and a temperature of 80-90°C to obtain modified boron-containing silicone oil;

[0025] The usage ratio of allyl alcohol, butyl phthalate and intermediate b is 0.02-0.03 mol: 0.1-0.12 g: 0.02-0.024 mol, and the usage ratio of intermediate c, terminal hydrogen-containing boron silicone oil and Castaplatin catalyst is 0.02-0.022 mol: 20-22 g: 1-1.2 mL;

[0026] During the reaction, under the action of butyl phthalate, allyl alcohol undergoes an ester exchange reaction with the silicon ethoxy group in the intermediate b, thereby introducing a double bond to obtain an intermediate c. Then, under the action of a castable platinum catalyst, the double bond in the intermediate c undergoes a hydrosilylation reaction with the hydrogen-terminated boron-containing silicone oil to obtain a modified boron-containing silicone oil.

[0027] Beneficial effects of the invention: The invention discloses a flame retardant and ultra-high temperature resistant ceramic silicone rubber material and a preparation method thereof. By adding a composite auxiliary agent, the problem that the flame retardant and high temperature resistance of the existing ceramic silicone rubber material decreases due to the addition of a flux is solved, and at the same time, the impact resistance of the ceramic silicone rubber material is improved, so that it can still maintain a certain working ability when a fire occurs; the composite auxiliary agent is prepared by compounding the precursor 3 in a modified boron-containing silicone oil through host-guest inclusion. Since the modified boron-containing silicone oil in the composite auxiliary agent contains a large number of unreacted silicon ethoxy groups, these groups allow the composite auxiliary agent to be cross-linked with the silicone oil and participate in the curing and molding process of the silicone rubber material, so that the composite auxiliary agent can exert better performance. At the same time, due to the boron nitride sheet structure present in the composite auxiliary agent, under high temperature aerobic conditions, part of the boron nitride sheet undergoes oxidation reaction to generate low-melting-point liquid boron oxide, which fills the gaps in the system to form a "bridge". , playing the role of flux, the unoxidized boron nitride sheet can play a good filling and supporting role. At the same time, due to the presence of the boron silicone oil structure of the composite additive, it will form a silicon-oxygen-boron structure when a fire occurs, and they combine with each other, thereby better improving the impact resistance of the silicone rubber after ceramicization. At the same time, due to the presence of 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide structure and a large number of nitrogen-containing groups in the composite additive, it combines with the cyclodextrin structure to form an expansion flame retardant system. At the same time, due to the presence of ferrocene, they cooperate with each other, which can greatly improve the flame retardant properties of ceramic silicone rubber. At the same time, due to the presence of Schiff base complexed platinum structure in the composite additive, it can play a good catalytic role, which improves the ceramic properties of silicone rubber to a certain extent, and its structure also has certain antioxidant activity, which avoids the decline of its catalytic performance during daily use and ensures the service life of ceramic silicone rubber. DETAILED DESCRIPTION

[0028] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. 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.

[0029] Embodiment 1 A method for preparing a flame-retardant and ultra-high temperature resistant ceramic silicone rubber material comprises the following steps: Step S1: Weigh the following raw materials in parts by weight: 40 parts of commercially available Lana white silicone oil, 10 parts of commercially available R972 white carbon black reinforcing filler, 40 parts of commercially available Hengyue Minerals mica ceramic filler, 15 parts of composite additives, 10 parts of commercially available Yingyu structure control agent, and 0.1 parts of commercially available ALL inhibitor;

[0030] Step S2: Silicone oil, reinforcing filler, ceramic filler, composite additive, structure control agent and inhibitor are mixed and added into a planetary mixer, stirred for 30 minutes at a speed of 50 rpm and room temperature, and then sent to a calendering line, cured for 5 minutes at a temperature of 120° C., to obtain a flame-retardant and ultra-high temperature resistant ceramic silicone rubber material;

[0031] The composite auxiliary agent is prepared by the following steps:

[0032] Step A1: commercially available XFNAN hexagonal boron nitride, urea and deionized water were mixed and added to a ball mill, and ball milled for 8 hours at a rotation speed of 800 rpm and room temperature to obtain amino boron nitride. Aminated boron nitride, p-formylbenzoic acid and ethanol were mixed, and anhydrous acetic acid was added under argon protection at a stirring rate of 100 rpm and a temperature of 80°C, and the reaction was carried out for 3 hours to obtain precursor 1;

[0033] The dosage ratio of hexagonal boron nitride, urea and deionized water is 2g:100g:180mL, and the dosage ratio of amidated boron nitride, p-formylbenzoic acid and anhydrous acetic acid is 0.15g:0.075mol:3mL;

[0034] Step A2: Precursor 1, 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide and anhydrous ethanol were mixed and ultrasonically dispersed for 15 minutes, and reacted for 4 hours at a stirring rate of 100 rpm and room temperature to obtain precursor 2. Precursor 2, mono-6-O-amino-β-cyclodextrin and deionized water were mixed and ultrasonically dispersed for 10 minutes, sodium carbonate solution was added to adjust the pH to 8, and then 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide and N-hydroxysuccinimide were added at a stirring rate of 100 rpm and a temperature of 35°C, and the reaction was carried out for 4 hours to obtain precursor 3;

[0035] The amount ratio of precursor 1, 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide and anhydrous ethanol is 0.18g:0.03mol:80mL, the mass fraction of sodium carbonate solution is 10%, the amount ratio of precursor 2, mono-6-O-amino-β-cyclodextrin, 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide and N-hydroxysuccinimide is 0.18g:2g:0.003mol:0.003mol;

[0036] Step A3: Precursor 3 and dichloromethane were mixed and ultrasonically dispersed for 20 minutes, and the modified boron-containing silicone oil was added under stirring at a stirring rate of 120 rpm and a temperature of 40° C., and stirred for 3 hours to obtain a composite auxiliary agent;

[0037] The amount ratio of precursor 3, dichloromethane and modified boron-containing silicone oil is 0.4g:60mL:20g;

[0038] The modified boron-containing silicone oil is prepared by the following steps:

[0039] Step B1: Mix ferrocenylboric acid and diethylene glycol dimethyl ether, stir at a stirring rate of 60 rpm and a temperature of 60° C., add concentrated sulfuric acid and dimethyldichlorosilane, react for 2 h, then add methyldichlorosilane, continue to react for 1.5 h, wash to neutrality, and dry to obtain terminal hydrogen-containing boron silicone oil;

[0040] The mass fraction of concentrated sulfuric acid is 60%, and the usage ratio of ferrocenylboric acid, diethylene glycol dimethyl ether, concentrated sulfuric acid, dimethyldichlorosilane and methyldichlorosilane is 0.05mol:400mL:100mL:0.4mol:0.05mol;

[0041] Step B2: salicylaldehyde, (3-aminopropyl)triethoxysilane and anhydrous ethanol were mixed, stirred under nitrogen protection, at a stirring rate of 80 rpm and a temperature of 80°C, and anhydrous acetic acid was added to react for 2 hours to obtain intermediate a; intermediate a, platinum acetate and dichloromethane were mixed, and reacted at a stirring rate of 40 rpm and room temperature for 24 hours to obtain intermediate b;

[0042] The amount ratio of salicylaldehyde, (3-aminopropyl)triethoxysilane and anhydrous acetic acid is 0.02 mol: 0.022 mol: 0.8 mL, and the amount ratio of intermediate a, platinum acetate and dichloromethane is 0.02 mol: 0.1 g: 20 mL;

[0043] Step B3: Mix allyl alcohol, butyl phthalate and toluene, stir at a stirring rate of 80 rpm and a temperature of 80°C, add intermediate b, and react for 2 hours to obtain intermediate c; mix intermediate c, hydrogen-terminated boron-containing silicone oil and Castaplatin catalyst, and react for 4 hours at a stirring rate of 50 rpm and a temperature of 80°C to obtain modified boron-containing silicone oil;

[0044] The usage ratio of allyl alcohol, butyl phthalate and intermediate b is 0.02 mol: 0.1 g: 0.02 mol, and the usage ratio of intermediate c, terminal hydrogen-containing borosilicate oil and Castaplatin catalyst is 0.022 mol: 20 g: 1 mL.

[0045] Example 2 A method for preparing a flame-retardant and ultra-high temperature resistant ceramic silicone rubber material comprises the following steps: Step S1: Weigh the following raw materials in parts by weight: 70 parts of commercially available Lana white silicone oil, 10 parts of commercially available R972 white carbon black reinforcing filler, 50 parts of commercially available Hengyue Minerals mica ceramic filler, 15 parts of composite additives, 20 parts of commercially available Yingyu structure control agent, and 0.4 parts of commercially available ALL inhibitor;

[0046] Step S2: Silicone oil, reinforcing filler, ceramic filler, composite additive, structure control agent and inhibitor are mixed and added into a planetary mixer, stirred for 30 minutes at a rotation speed of 50 rpm and room temperature, and then sent to a calendering line, cured for 5 minutes at a temperature of 140° C., to obtain a flame-retardant and ultra-high temperature resistant ceramic silicone rubber material;

[0047] The composite auxiliary agent is prepared by the following steps:

[0048] Step A1: commercially available XFNAN hexagonal boron nitride, urea and deionized water were mixed and added to a ball mill, and ball milled for 10 hours at a rotation speed of 800 rpm and room temperature to obtain amino boron nitride. Aminated boron nitride, p-formylbenzoic acid and ethanol were mixed, and anhydrous acetic acid was added under argon protection at a stirring rate of 100 rpm and a temperature of 80°C, and the reaction was carried out for 4 hours to obtain precursor 1;

[0049] The dosage ratio of hexagonal boron nitride, urea and deionized water is 3g:100g:180mL, and the dosage ratio of amidated boron nitride, p-formylbenzoic acid and anhydrous acetic acid is 0.15g:0.08mol:3mL;

[0050] Step A2: Precursor 1, 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide and anhydrous ethanol were mixed and ultrasonically dispersed for 15 minutes, and reacted for 6 hours at a stirring rate of 100-120 rpm and room temperature to obtain precursor 2. Precursor 2, mono-6-O-amino-β-cyclodextrin and deionized water were mixed and ultrasonically dispersed for 10 minutes, sodium carbonate solution was added to adjust the pH to 8, and then 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide and N-hydroxysuccinimide were added at a stirring rate of 100 rpm and a temperature of 35°C, and the reaction was carried out for 6 hours to obtain precursor 3;

[0051] The amount ratio of precursor 1, 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide and anhydrous ethanol is 0.18 g: 0.04 mol: 80 mL, the mass fraction of sodium carbonate solution is 10%, and the amount ratio of precursor 2, mono-6-O-amino-β-cyclodextrin, 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide and N-hydroxysuccinimide is 0.2 g: 2 g: 0.003 mol: 0.003 mol;

[0052] Step A3: Precursor 3 and dichloromethane were mixed and ultrasonically dispersed for 20 minutes, and the modified boron-containing silicone oil was added under stirring at a stirring rate of 160 rpm and a temperature of 40° C., and stirred for 3 hours to obtain a composite auxiliary agent;

[0053] The amount ratio of precursor 3, dichloromethane and modified boron-containing silicone oil is 0.48g:60mL:22g;

[0054] The modified boron-containing silicone oil is prepared by the following steps:

[0055] Step B1: Mix ferrocenylboric acid and diethylene glycol dimethyl ether, stir at a stirring rate of 60 rpm and a temperature of 60° C., add concentrated sulfuric acid and dimethyldichlorosilane, react for 2.5 hours, then add methyldichlorosilane, continue to react for 2 hours, wash until neutral, and dry to obtain terminal hydrogen-containing boron silicone oil;

[0056] The mass fraction of concentrated sulfuric acid is 60%, and the usage ratio of ferrocenylboric acid, diethylene glycol dimethyl ether, concentrated sulfuric acid, dimethyldichlorosilane and methyldichlorosilane is 0.05mol:400mL:120mL:0.4mol:0.05mol;

[0057] Step B2: salicylaldehyde, (3-aminopropyl)triethoxysilane and anhydrous ethanol were mixed, stirred under nitrogen protection, at a stirring rate of 100 rpm and a temperature of 80°C, and anhydrous acetic acid was added, and the reaction was carried out for 2 hours to obtain intermediate a; intermediate a, platinum acetate and dichloromethane were mixed, and the reaction was carried out for 24 hours at a stirring rate of 40 rpm and room temperature to obtain intermediate b;

[0058] The amount ratio of salicylaldehyde, (3-aminopropyl)triethoxysilane and anhydrous acetic acid is 0.02 mol: 0.032 mol: 1 mL, and the amount ratio of intermediate a, platinum acetate and dichloromethane is 0.02 mol: 0.11 g: 20 mL;

[0059] Step B3: Mix allyl alcohol, butyl phthalate and toluene, stir at a stirring rate of 100 rpm and a temperature of 80°C, add intermediate b, and react for 2 hours to obtain intermediate c; mix intermediate c, hydrogen-terminated boron-containing silicone oil and Castaplatin catalyst, and react for 6 hours at a stirring rate of 60 rpm and a temperature of 80°C to obtain modified boron-containing silicone oil;

[0060] The usage ratio of allyl alcohol, butyl phthalate and intermediate b is 0.03 mol: 0.1 g: 0.024 mol, and the usage ratio of intermediate c, terminal hydrogen-containing boron silicone oil and Castaplatin catalyst is 0.02 mol: 22 g: 1 mL.

[0061] Example 3 A method for preparing a flame-retardant and ultra-high temperature resistant ceramic silicone rubber material, comprising the following steps: Step S1: Weigh the following raw materials in parts by weight: 70 parts of commercially available Lana white silicone oil, 15 parts of commercially available R972 white carbon black reinforcing filler, 50 parts of commercially available Hengyue Minerals mica ceramic filler, 25 parts of composite additives, 20 parts of commercially available Yingyu structure control agent, and 0.4 parts of commercially available ALL inhibitor;

[0062] Step S2: Silicone oil, reinforcing filler, ceramic filler, composite additive, structure control agent and inhibitor are mixed and added into a planetary mixer, stirred for 30 minutes at a rotation speed of 50 rpm and room temperature, and then sent to a calendering line, cured for 5 minutes at a temperature of 140° C., to obtain a flame-retardant and ultra-high temperature resistant ceramic silicone rubber material;

[0063] The composite auxiliary agent is prepared by the following steps:

[0064] Step A1: commercially available XFNAN hexagonal boron nitride, urea and deionized water were mixed and added to a ball mill, and ball milled for 10 hours at a rotation speed of 800 rpm and room temperature to obtain amino boron nitride. Aminated boron nitride, p-formylbenzoic acid and ethanol were mixed, and anhydrous acetic acid was added under argon protection at a stirring rate of 120 rpm and a temperature of 80°C, and the reaction was carried out for 4 hours to obtain precursor 1;

[0065] The dosage ratio of hexagonal boron nitride, urea and deionized water is 3g:100g:200mL, and the dosage ratio of amination boron nitride, p-formylbenzoic acid and anhydrous acetic acid is 0.18g:0.08mol:4mL;

[0066] Step A2: Precursor 1, 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide and anhydrous ethanol were mixed and ultrasonically dispersed for 15 minutes, and reacted for 6 hours at a stirring rate of 120 rpm and room temperature to obtain precursor 2. Precursor 2, mono-6-O-amino-β-cyclodextrin and deionized water were mixed and ultrasonically dispersed for 10 minutes, sodium carbonate solution was added to adjust the pH to 8, and then 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide and N-hydroxysuccinimide were added at a stirring rate of 120 rpm and a temperature of 35°C, and the reaction was carried out for 6 hours to obtain precursor 3;

[0067] The amount ratio of precursor 1, 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide and anhydrous ethanol is 0.2g:0.04mol:90mL, the mass fraction of sodium carbonate solution is 10%, and the amount ratio of precursor 2, mono-6-O-amino-β-cyclodextrin, 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide and N-hydroxysuccinimide is 0.2g:2.4g:0.003mol:0.003mol;

[0068] Step A3: Precursor 3 and dichloromethane were mixed and ultrasonically dispersed for 20 minutes, and the modified boron-containing silicone oil was added under stirring at a stirring rate of 160 rpm and a temperature of 40° C., and stirred for 4 hours to obtain a composite auxiliary agent;

[0069] The amount ratio of precursor 3, dichloromethane and modified boron-containing silicone oil is 0.48 g: 80 mL: 22 g;

[0070] The modified boron-containing silicone oil is prepared by the following steps:

[0071] Step B1: Mix ferrocenylboric acid and diethylene glycol dimethyl ether, stir at a stirring rate of 80 rpm and a temperature of 60° C., add concentrated sulfuric acid and dimethyldichlorosilane, react for 2.5 hours, then add methyldichlorosilane, continue to react for 2 hours, wash until neutral, and dry to obtain terminal hydrogen-containing boron silicone oil;

[0072] The mass fraction of concentrated sulfuric acid is 60%, and the amount ratio of ferrocenylboric acid, diethylene glycol dimethyl ether, concentrated sulfuric acid, dimethyldichlorosilane and methyldichlorosilane is 0.05mol:500mL:120mL:0.5mol:0.05mol;

[0073] Step B2: salicylaldehyde, (3-aminopropyl)triethoxysilane and anhydrous ethanol were mixed, stirred under nitrogen protection, at a stirring rate of 100 rpm and a temperature of 80°C, and anhydrous acetic acid was added, and the reaction was carried out for 3 hours to obtain intermediate a; intermediate a, platinum acetate and dichloromethane were mixed, and the reaction was carried out for 24 hours at a stirring rate of 60 rpm and room temperature to obtain intermediate b;

[0074] The amount ratio of salicylaldehyde, (3-aminopropyl)triethoxysilane and anhydrous acetic acid is 0.03 mol: 0.032 mol: 1 mL, and the amount ratio of intermediate a, platinum acetate and dichloromethane is 0.03 mol: 0.11 g: 25 mL;

[0075] Step B3: Mix allyl alcohol, butyl phthalate and toluene, stir at a stirring rate of 100 rpm and a temperature of 80°C, add intermediate b, and react for 3 hours to obtain intermediate c; mix intermediate c, hydrogen-terminated boron-containing silicone oil and Castaplatin catalyst, and react for 6 hours at a stirring rate of 60 rpm and a temperature of 90°C to obtain modified boron-containing silicone oil;

[0076] The usage ratio of allyl alcohol, butyl phthalate and intermediate b is 0.03 mol: 0.12 g: 0.024 mol, and the usage ratio of intermediate c, terminal hydrogen-containing borosilicate oil and Castaplatin catalyst is 0.022 mol: 22 g: 1.2 mL.

[0077] Comparative Example 1 Compared with Example 3, this comparative example replaces the composite additive in Example 3 with the commercially available Zenlong 480 flux, and the other steps are the same.

[0078] Comparative Example 2 Compared with Example 3, this comparative example is characterized in that the precursor 3 of Example 3 in the preparation process of the composite auxiliary agent of Example 3 is replaced by the precursor 1 of Example 3, and the other steps are the same.

[0079] Comparative Example 3 Compared with Example 3, this comparative example is characterized in that ferrocenylboric acid in the preparation process of the modified boron-containing silicone oil in Example 3 is replaced by phenylboric acid, and the other steps are the same.

[0080] Comparative Example 4 Compared with Example 3, this comparative example removes the platinum acetate in the preparation process of the modified boron-containing silicone oil in Example 3, and adds 0.1 parts by weight of commercially available silicone platinum catalyst in the preparation process of the flame retardant and ultra-high temperature resistant ceramic silicone rubber material, and the other steps are the same.

[0081] Take the flame retardant and ultra-high temperature resistant ceramic silicone rubber materials prepared in Example 1, Example 2, Example 3, Comparative Example 1, Comparative Example 2, Comparative Example 3 and Comparative Example 4, make the ceramic silicone rubber material into a 100mm×10mm×3mm sample, refer to GB / T 10707-2008, test its limiting oxygen index and vertical combustion grade, make the foam sealing strip material into a 50mm×10mm×6mm sample, sinter it at 600°C in a muffle furnace for 2h, measure the compressive strength of the ablated product when it is destroyed by a universal testing machine, and characterize its impact resistance by the maximum force required to destroy the sample, place the ceramic silicone rubber material in a precision blast drying oven for hot air aging test, heat age for 240h at a temperature of 120°C, and then test its impact resistance. The test results are as follows:

[0082]

[0083] It can be seen from the test results in the table shown that when Example 1, Example 2 and Example 3 are compared with Comparative Example 1, Comparative Example 2, Comparative Example 3 and Comparative Example 4, Comparative Example 1 replaces the composite additive of Example 3 with the commercially available Zenlong 480 flux, and its various properties are significantly reduced. Comparative Example 2 replaces the precursor 3 of Example 3 in the preparation process of the composite additive of Example 3 with the precursor 1 of Example 3. Due to the lack of phosphorus-containing structure and cyclodextrin structure, its flame retardant performance and impact resistance after ceramicization are greatly reduced. Comparative Example 3 replaces the modified containing of Example 3 with the precursor 1 of Example 3. Ferrocene boric acid in the preparation process of borosilicate oil is replaced by phenylboric acid. Due to the lack of ferrocene structure, its flame retardant properties are reduced to a certain extent. At the same time, the inclusion structure cannot be formed, resulting in the inability of precursor 3 to be dispersed in the matrix, which in turn leads to a significant decrease in its performance after ceramicization. In comparative example 4, the platinum acetate in the preparation process of the modified borosilicate oil in Example 3 is removed, and 0.1 parts by weight of platinum catalyst is added during the preparation of the flame-retardant and ultra-high temperature resistant ceramic silicone rubber material. Due to the lack of antioxidant protection of the imine structure, its performance is reduced after thermal aging.

[0084] In the description of the specification, the description with reference to the terms "one embodiment", "example", "specific example", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0085] The above contents are merely examples and explanations of the concept of the present invention. The technicians in this technical field may make various modifications or additions to the specific embodiments described or replace them in a similar manner. As long as they do not deviate from the concept of the invention or exceed the scope defined by the claims, they should all fall within the protection scope of the present invention.

Claims

1. A method for preparing a flame retardant and ultra-high temperature resistant ceramic silicone rubber material, characterized in that: The method comprises the following steps: Step S1: weighing the following raw materials in parts by weight: 40-70 parts of silicone oil, 10-15 parts of reinforcing filler, 40-50 parts of porcelain-forming filler, 15-25 parts of composite auxiliary agent, 10-20 parts of structure control agent, and 0.15-0.4 parts of inhibitor; Step S2: Silicone oil, reinforcing filler, ceramic filler, composite additive, structure control agent and inhibitor are mixed and added into a planetary mixer, stirred for 30 minutes at a speed of 50 rpm and room temperature, and then sent to a calendering line, cured for 5 minutes at a temperature of 120-140° C., to obtain a flame-retardant and ultra-high temperature resistant ceramic silicone rubber material; The composite auxiliary agent is prepared by the following steps: Step A1: hexagonal boron nitride, urea and deionized water are mixed and added to a ball mill, and ball milled for 8-10 hours at a rotation speed of 800 rpm and room temperature to obtain amino boron nitride; amino boron nitride, paraformylbenzoic acid and ethanol are mixed, and anhydrous acetic acid is added under argon protection at a stirring rate of 100-120 rpm and a temperature of 80°C, and the reaction is carried out for 3-4 hours to obtain a precursor 1; Step A2: Precursor 1, 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide and anhydrous ethanol are mixed and ultrasonically dispersed for 15 minutes, and reacted for 4-6 hours at room temperature with a stirring rate of 100-120 rpm to obtain precursor 2. Precursor 2, mono-6-O-amino-β-cyclodextrin and deionized water are mixed and ultrasonically dispersed for 10 minutes, and sodium carbonate solution is added to adjust the pH to 8. Then, 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide and N-hydroxysuccinimide are added under stirring at a stirring rate of 100-120 rpm and a temperature of 35° C., and the reaction is carried out for 4-6 hours to obtain precursor 3; Step A3: Precursor 3 and dichloromethane were mixed and ultrasonically dispersed for 20 minutes, and the modified boron-containing silicone oil was added under stirring at a stirring rate of 120-160 rpm and a temperature of 40° C., and stirred for 3-4 hours to obtain a composite auxiliary agent; The precursor 3 is compounded in the modified boron-containing silicone oil through the host-guest inclusion complex between the ferrocene structure in the modified boron-containing silicone oil and the cyclodextrin structure in the precursor 3, thereby preparing a composite auxiliary agent.

2. The method for preparing a flame retardant and ultra-high temperature resistant ceramic silicone rubber material according to claim 1, characterized in that: In step A1, the ratio of hexagonal boron nitride, urea and deionized water is 2-3 g: 100 g: 180-200 mL, and the ratio of amination boron nitride, p-formylbenzoic acid and anhydrous acetic acid is 0.15-0.18 g: 0.075-0.08 mol: 3-4 mL.

3. The method for preparing a flame retardant and ultra-high temperature resistant ceramic silicone rubber material according to claim 1, characterized in that: In step A2: the amount ratio of precursor 1, 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide and anhydrous ethanol is 0.18-0.2g: 0.03-0.04mol: 80-90mL, the mass fraction of sodium carbonate solution is 10%, and the amount ratio of precursor 2, mono-6-O-amino-β-cyclodextrin, 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide and N-hydroxysuccinimide is 0.18-0.2g: 2-2.4g: 0.003mol: 0.003mol.

4. The method for preparing a flame retardant and ultra-high temperature resistant ceramic silicone rubber material according to claim 1, characterized in that: In step A3: the ratio of precursor 3, dichloromethane and modified boron-containing silicone oil is 0.4-0.48 g: 60-80 mL: 20-22 g.

5. The method for preparing a flame retardant and ultra-high temperature resistant ceramic silicone rubber material according to claim 1, characterized in that: The modified boron-containing silicone oil is prepared by the following steps: Step B1: Mix ferrocenylboric acid and diethylene glycol dimethyl ether, stir at a stirring rate of 60-80 rpm and a temperature of 60° C., add concentrated sulfuric acid and dimethyldichlorosilane, react for 2-2.5 hours, then add methyldichlorosilane, continue to react for 1.5-2 hours, wash until neutral, and dry to obtain terminal hydrogen-containing boron silicone oil; Step B2: salicylaldehyde, (3-aminopropyl)triethoxysilane and anhydrous ethanol are mixed, stirred at a stirring rate of 80-100 rpm and a temperature of 80°C under nitrogen protection, and anhydrous acetic acid is added for reaction for 2-3 hours to obtain intermediate a; intermediate a, platinum acetate and dichloromethane are mixed, stirred at a stirring rate of 40-60 rpm and room temperature for reaction for 24 hours to obtain intermediate b; Step B3: Mix allyl alcohol, butyl phthalate and toluene, stir and add intermediate b at a stirring rate of 80-100 rpm and a temperature of 80°C, and react for 2-3 hours to obtain intermediate c. Mix intermediate c, terminal hydrogen-containing borosilicate oil and Castell platinum catalyst, stir at a rate of 50-60 rpm and a temperature of 80-90°C, and react for 4-6 hours to obtain modified borosilicate oil.

6. The method for preparing a flame retardant and ultra-high temperature resistant ceramic silicone rubber material according to claim 5, characterized in that: In step B1: the mass fraction of concentrated sulfuric acid is 60%, and the usage ratio of ferrocenylboric acid, diethylene glycol dimethyl ether, concentrated sulfuric acid, dimethyldichlorosilane and methyldichlorosilane is 0.05mol:400-500mL:100-120mL:0.4-0.5mol:0.05mol.

7. The method for preparing a flame retardant and ultra-high temperature resistant ceramic silicone rubber material according to claim 5, characterized in that: In step B2, the ratio of salicylaldehyde, (3-aminopropyl)triethoxysilane and anhydrous acetic acid is 0.02-0.03 mol: 0.022-0.032 mol: 0.8-1 mL, and the ratio of intermediate a, platinum acetate and dichloromethane is 0.02-0.03 mol: 0.1-0.11 g: 20-25 mL.

8. The method for preparing a flame retardant and ultra-high temperature resistant ceramic silicone rubber material according to claim 5, characterized in that: In step B3: the usage ratio of allyl alcohol, butyl phthalate and intermediate b is 0.02-0.03 mol: 0.1-0.12 g: 0.02-0.024 mol, and the usage ratio of intermediate c, terminal hydrogen-containing boron silicone oil and Castaplatin catalyst is 0.02-0.022 mol: 20-22 g: 1-1.2 mL.

9. A flame retardant and ultra-high temperature resistant ceramic silicone rubber material, characterized in that: Prepared according to any one of claims 1 to 8.

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