Environment-friendly organic silicon intumescent fireproof coating for transformer substation or converter station as well as preparation method and application of environment-friendly organic silicon intumescent fireproof coating

Abstract

The invention discloses an environment-friendly organic silicon intumescent fireproof coating for a transformer substation or a converter station as well as a preparation method and application of the environment-friendly organic silicon intumescent fireproof coating. The coating comprises the following raw materials in parts by mass: 30-60 parts of organic silicon resin, 30-45 parts of an intumescent flame retardant, 5-10 parts of modified glass powder, 2-20 parts of an inorganic filler, 2-10 parts of an auxiliary agent and 5-25 parts of a curing agent. The intumescent flame retardant takes a phosphazene compound as a gas source and an acid source; the phosphazene compound is prepared by carrying out nucleophilic substitution reaction on phosphonitrilic chloride trimer and melamine or dicyandiamide; the modified glass powder is prepared by mixing a plurality of glass powder with the melting point of 350-700 DEG C and then modifying by adopting a silane coupling agent. According to the invention, the high-temperature resistance of the organic silicon resin coating is improved through formula design, so that the service life of the steel in a high-temperature scene is prolonged, the performance reliability of fire-fighting equipment of a transformer substation or a converter station is improved, and the purpose of high-temperature resistance is achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of fire retardant coatings, and in particular to an environmentally friendly organic silicon intumescent fire retardant coating for a transformer substation or a converter station, and a preparation method and application thereof. Background Art

[0002] With the rapid construction of UHV power transmission in my country, the fire protection capability of UHV stations has become an unavoidable issue. The oil storage capacity of UHV transformers is as high as hundreds of tons. Once a fire occurs, the flame temperature can reach over 1200℃, and the commonly used fire retardant coatings cannot withstand such high temperatures. And as environmental protection requirements become increasingly stringent, the composition of the coatings also tends to use green and environmentally friendly substances.

[0003] The heat resistance of high temperature resistant coatings is not only closely related to the base resin, but also to the type and content of high temperature resistant pigments and fillers in the coatings. Pure silicone resins can usually only withstand temperatures of 200 to 300°C. Adding appropriate pigments and fillers can produce coatings that can withstand temperatures of 300 to 700°C. Commonly used high temperature resistant pigments and fillers include SiC, ZrO 2 、Al 2 O 3 、TiO 2 、SiO 2 , ZnO, mica powder, talc, kaolin, aluminum powder, chrome iron black and glass powder with different melting points, etc. Commonly used solvents are generally aromatic hydrocarbons, esters, alcohols and ketones, such as xylene, butyl acetate, butanol, cyclohexanone, etc. Nowadays, the performance characteristics of ordinary silicone coatings can no longer meet the growing needs of the industry. Intumescent fire retardant coating is a functional coating that is applied to the surface of the substrate and can react in the event of fire to generate a carbon layer with a thickness much higher than the original coating, thereby reducing heat conduction to the substrate and increasing the fire resistance limit of the protected substrate. Therefore, based on the principle of intumescent flame retardancy, it is expected to further improve the high temperature resistance of silicone coatings (temperature resistance of not less than 1200°C) for application scenarios such as fire substations. Summary of the invention

[0004] The technical problem to be solved by the present invention is how to improve the high temperature resistance of the silicone resin coating to meet the use requirements of the fire protection facilities of substations and converter stations.

[0005] The present invention solves the above technical problems through the following technical means:

[0006] An environmentally friendly organic silicon intumescent fire retardant coating for a transformer substation or a converter station, wherein the raw materials thereof include, by weight: 30-60 parts of organic silicon resin, 30-45 parts of intumescent flame retardant, 5-10 parts of modified glass powder, 2-20 parts of inorganic filler, 2-10 parts of auxiliary agent, and 5-25 parts of curing agent;

[0007] The intumescent flame retardant uses a phosphazene compound as a gas source and an acid source; the phosphazene compound is formed by a nucleophilic substitution reaction between hexachlorocyclotriphosphazene and melamine or dicyandiamide;

[0008] The modified glass powder is prepared by mixing a plurality of glass powders with melting points of 350° C. to 700° C. and then modifying them with a silane coupling agent.

[0009] Preferably, the organic silicone resin is an epoxy-modified organic silicone resin.

[0010] Preferably, the acid source of the intumescent flame retardant further includes ammonium polyphosphate, ammonium polyphosphate or a mixture of the two.

[0011] Preferably, the mass ratio of ammonium polyphosphate, a mixture of one or both of ammonium polyphosphate and the phosphazene compound is 1-2:1-2.

[0012] Preferably, the carbon source of the intumescent flame retardant is a mixture of one or more of pentaerythritol, dipentaerythritol, starch and expanded graphite.

[0013] Preferably, the carbon source of the intumescent flame retardant is pentaerythritol.

[0014] Preferably, the mass ratio of the phosphazene compound to the intumescent flame retardant carbon source is 1-4:1.

[0015] Preferably, the modified glass powder is prepared by mixing three kinds of glass powders with melting points of 350° C., 500° C. and 700° C. and then modifying them with a silane coupling agent.

[0016] Preferably, the mass ratio of the three glass powders with melting points of 350° C., 500° C. and 700° C. is 1:1:1.

[0017] Preferably, the preparation process of the modified glass powder comprises the following steps: grinding and sieving a variety of glass powders with melting points of 350°C-700°C, mixing and ball milling, mixing with ethanol and water, adding a silane coupling agent, heating for reaction, and drying to obtain the modified glass powder.

[0018] Preferably, the heating reaction temperature is 60° C. and the time is 12 h.

[0019] Preferably, the silane coupling agent is an amino-functional silane coupling agent.

[0020] Preferably, the silane coupling agent is silane coupling agent KH-570.

[0021] Preferably, the mass ratio of the silane coupling agent to the glass powder is 1:1-5.

[0022] Preferably, the inorganic filler is talc, Mxene, graphene, expanded graphite, vermiculite, Al 2 O 3 , a mixture of one or more of nano titanium dioxide.

[0023] Preferably, the inorganic filler is talcum powder, expanded graphite or a mixture of the two.

[0024] Preferably, the auxiliary agent is an adhesion promoter.

[0025] Preferably, the adhesion promoter includes a mixture of one or more of polyester phosphate 5063A adhesion promoter, 5140B water-based adhesion promoter, and AKN-6618 adhesion promoter.

[0026] Preferably, the curing agent is a mixture of one or more of polyurethane, amino compound and organopolysilazane.

[0027] Preferably, the raw material of the environmentally friendly organic silicon intumescent fire retardant coating for the substation or converter station also includes water.

[0028] Preferably, the mass ratio of the silicone resin to water is 3-5:5-7.

[0029] The present invention also proposes a method for preparing the environmentally friendly organic silicon intumescent fire retardant coating for substations or converter stations, comprising the following steps: mixing an inorganic filler, an intumescent flame retardant and a modified glass powder by ball milling to obtain a composite filler; preparing an aqueous solution of an organic silicon resin, adding the composite filler and an auxiliary agent, heating and stirring, then adding a curing agent and stirring to obtain the environmentally friendly organic silicon intumescent fire retardant coating for substations or converter stations.

[0030] Preferably, the mass concentration of the organic silicone resin aqueous solution is 30-50%.

[0031] Preferably, the curing agent is added after heating to 50° C. and stirring for 60 minutes.

[0032] The present invention also provides a coating, which is prepared by using the environmentally friendly organic silicon expansion fire retardant coating for transformer substation or converter station.

[0033] The present invention also proposes an application of the environmentally friendly organic silicon intumescent fire retardant coating for a transformer substation or a converter station in the transformer substation or the converter station.

[0034] The advantages of the present invention are:

[0035] In the present invention, the high temperature resistance of the silicone resin coating is improved through formula design, so as to enhance the service life of the steel in high temperature scenes and improve the performance reliability of the fire protection facilities of the substation or converter station, thereby achieving the purpose of high temperature resistance.

[0036] The environmentally friendly organic silicon intumescent fire-retardant coating provided by the present invention can withstand 1200° C. in a short term and 700° C. in a long term, and will not generate a large amount of toxic gas and smoke when burned.

[0037] In the present invention, the modified glass powder has a great influence on the high temperature resistance of the coating, and the high temperature resistant inorganic filler cooperates with the silicone resin to improve the high temperature resistance of the coating. The addition of the adhesion promoter has a certain improvement effect on the adhesion and dispersibility of the coating. The present invention can effectively improve the high temperature resistance of the coating under the synergistic compounding of the silicone resin, the intumescent flame retardant, the modified glass powder and the high temperature resistant inorganic filler.

[0038] The present invention utilizes an expansion flame retardant system and realizes secondary film formation of an organic silicon expansion flame retardant coating at high temperature by compounding and modifying glass powders with different melting points, thereby improving the high temperature resistance of the organic silicon expansion flame retardant coating.

[0039] The coating of the present invention has a simple and environmentally friendly preparation process. The functional filler used in the coating is fully mixed by ball milling the intumescent flame retardant, the high temperature resistant inorganic filler and the modified glass powder. The filler and the silicone resin are fully reacted by aqueous solution and silane coupling agent. The coating preparation process and components are green and environmentally friendly and harmless to human body.

[0040] The environmentally friendly organic silicon intumescent fire-retardant coating prepared by the invention has a temperature resistance of 1200° C., generates an intumescent flame-retardant carbon layer, and can play a good fire-retardant role on the base material.

[0041] The organic silicon intumescent fire retardant coating prepared by the invention can be cured at room temperature. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] Figure 1 is an infrared spectrum of the phosphazene compound prepared in Example 1 of the present invention;

[0043] Figure 2 is the XRD spectrum of the phosphazene compound prepared in Example 1 of the present invention;

[0044] Figure 3 is a thermogravimetric curve of the phosphazene compound prepared in Example 1 of the present invention;

[0045] Figure 4 is a scanning electron microscope image of the phosphazene compound prepared in Example 1 of the present invention;

[0046] Figure 5 This is a back temperature test diagram of the organosilicon intumescent fire retardant coating prepared in Examples 1-4 of the present invention;

[0047] Figure 6This is a digital image of the coating and carbon layer of the organic silicon intumescent fire retardant coating prepared in Example 1 of the present invention;

[0048] Figure 7 The digital image (left) and the scanned image (right) of the expanded carbon layer of the organosilicon intumescent fire retardant coating prepared in Example 2 of the present invention;

[0049] Figure 8 This is a digital image of the coating of the fire retardant coating prepared in Comparative Example 2 of the present invention;

[0050] Fig. 9 This is a back temperature test diagram of the coatings prepared in Comparative Examples 1-7 of the present invention. DETAILED DESCRIPTION

[0051] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described in combination with the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0052] Unless otherwise specified, the test materials and reagents used in the following examples can be obtained from commercial sources.

[0053] If no specific techniques or conditions are specified in the examples, they can be carried out according to the techniques or conditions described in the literature in the art or according to the product instructions.

[0054] In the following examples and comparative examples, the melting point of the glass powder is the temperature at which the glass powder begins to melt;

[0055] The glass powder with a melting point of 350°C is GT-35 low melting point glass powder, and the manufacturer is Anmi Micro-Nano New Materials (Guangzhou) Co., Ltd.;

[0056] The glass powder with a melting point of 500°C is GT-50 low melting point glass powder, and the manufacturer is Anmi Micro-Nano New Materials (Guangzhou) Co., Ltd.

[0057] The glass powder with a melting point of 700°C is GT-70 low-melting-point glass powder, and the manufacturer is Anmi Micro-Nano New Materials (Guangzhou) Co., Ltd.

[0058] The SJ-804 epoxy modified silicone resin is sourced from Congyang County Sanjin Pigment Co., Ltd.

[0059] The polyurethane curing agent is WANNATE HT-100 produced by Wanhua Chemical Group Co., Ltd.

[0060] The polyester phosphate 5063A adhesion promoter is sourced from Guangdong Nuoyi Chemical Co., Ltd.

[0061] Example 1

[0062] The invention discloses an environmentally friendly organic silicon intumescent fire retardant coating for a transformer substation or a converter station. The raw materials thereof include, by weight: 40 parts of SJ-804 epoxy modified organic silicon resin, 40 parts of intumescent flame retardant, 8 parts of modified glass powder, 5 parts of talcum powder, 4 parts of polyester phosphate 5063A adhesion promoter, and 10 parts of polyurethane curing agent.

[0063] The intumescent flame retardant comprises a phosphazene compound as an integrated gas source and acid source, ammonium polyphosphate as an acid source, and pentaerythritol as a carbon source, and the mass ratio of the phosphazene compound, ammonium polyphosphate and pentaerythritol is 2:2:1.

[0064] The preparation steps of the phosphazene compound are as follows: hexachlorocyclotriphosphazene and melamine (the mass ratio of hexachlorocyclotriphosphazene to melamine is 1:1) are refluxed in a pyridine solution (the mass concentration of hexachlorocyclotriphosphazene in the pyridine solution is 30%) at 100° C. for 12 hours for nucleophilic substitution, and the phosphazene compound is obtained after centrifugal drying.

[0065] The modified glass powder is prepared by compounding glass powders with melting points of 350°C, 500°C and 700°C in a mass ratio of 1:1:1 and then modified with silane. The specific preparation process of the modified glass powder is as follows:

[0066] (1) grinding glass powders with melting points of 350° C., 500° C., and 700° C. in a mass ratio of 1:1:1, sieving and mixing, and ball milling for 30 minutes to obtain a composite glass powder;

[0067] (2) 10 parts by weight of the composite glass powder was dispersed in an ethanol / water solution to prepare an ethanol / water mixed solution (volume ratio of ethanol:water=8:2, mass concentration of the glass powder in the solution was 25%), and then 2 parts by weight of silane coupling agent KH570 was added, and mechanically stirred for 30 minutes to ensure that the glass powder was evenly mixed;

[0068] (3) The temperature of the modified system is kept constant at 60° C., the reaction is carried out for 12 hours, and the modified glass powder is obtained after freeze-drying.

[0069] The preparation process of environmentally friendly silicone intumescent fire retardant coating for substation or converter station is as follows:

[0070] (1) Grinding an intumescent flame retardant, modified glass powder, and talcum powder, sieving, and ball milling for 30 minutes to obtain a composite filler;

[0071] (2) preparing a 40% by mass SJ-804 epoxy modified silicone resin aqueous solution, adding the composite filler and polyester phosphate ester 5063A adhesion promoter in step (1), and stirring at 50° C. for 60 min;

[0072] (3) Add polyurethane curing agent and stir for 30 minutes to obtain a uniformly mixed organic silicon intumescent fire retardant coating, and apply the coating by brush. The substrate is stainless steel and the coating thickness is 3 mm.

[0073] Example 2

[0074] The invention discloses an environmentally friendly organic silicon intumescent fire retardant coating for a transformer substation or a converter station. The raw materials thereof include, by weight: 40 parts of SJ-804 epoxy modified organic silicon resin, 35 parts of intumescent flame retardant, 8 parts of modified glass powder, 3 parts of talcum powder, 4 parts of polyester phosphate 5063A adhesion promoter, and 10 parts of polyurethane curing agent.

[0075] The intumescent flame retardant comprises a phosphazene compound as a gas source and an acid source, ammonium polyphosphate as an acid source, and expanded graphite as a carbon source, and the mass ratio of the phosphazene compound, ammonium polyphosphate and expanded graphite is 2:1:1.

[0076] The synthesis steps of the phosphazene compound are as follows: hexachlorocyclotriphosphazene and dicyandiamide (molar ratio of 1:3) are refluxed in a pyridine solution (the mass concentration of hexachlorocyclotriphosphazene in the pyridine solution is 30%) at 100°C for 12 hours for nucleophilic substitution, and after centrifugal drying, a phosphazene compound is obtained as a gas source and acid source for an intumescent flame retardant.

[0077] The modified glass powder is a modified glass powder obtained by compounding glass powders with melting points of 350°C, 500°C and 700°C in a mass ratio of 1:1:1 and then using silane to modify the glass powder. The specific preparation process of the modified glass powder is as follows:

[0078] (1) grinding glass powders with melting points of 350° C., 500° C., and 700° C. in a mass ratio of 1:1:1, sieving and mixing, and ball milling for 30 minutes to obtain a composite glass powder;

[0079] (2) 10 parts by mass of the composite glass powder were weighed according to the proportion and dispersed in an ethanol / water solution (volume ratio of ethanol: water = 8:2, the mass concentration of the glass powder in the solution was 25%), 8 parts by mass of silane coupling agent KH-570 were added, refluxed at 60° C. for 12 h, and freeze-dried to obtain the modified glass powder.

[0080] The preparation process of environmentally friendly silicone intumescent fire retardant coating for substation or converter station is as follows:

[0081] (1) Grinding an intumescent flame retardant, modified glass powder, and talcum powder, sieving, and ball milling for 30 minutes to obtain a composite filler;

[0082] (2) preparing a 40% by mass SJ-804 epoxy modified silicone resin aqueous solution, adding the composite filler and polyester phosphate ester 5063A adhesion promoter in step (1), and stirring at 50° C. for 60 min;

[0083] (3) Add polyurethane curing agent and stir for 30 minutes to obtain a uniformly mixed organic silicon intumescent fire retardant coating, and apply the coating by brush. The substrate is stainless steel and the coating thickness is 3 mm.

[0084] Example 3

[0085] The invention discloses an environmentally friendly organic silicon intumescent fire retardant coating for a transformer substation or a converter station. The raw materials thereof include, by weight, 40 parts of SJ-804 epoxy modified organic silicon resin, 45 parts of intumescent flame retardant, 5 parts of modified glass powder, 2 parts of talcum powder, 2 parts of polyester phosphate 5063A adhesion promoter, and 6 parts of polyurethane curing agent.

[0086] The intumescent flame retardant comprises a phosphazene compound as a gas source and an acid source, ammonium polyphosphate as an acid source, and starch as a carbon source, and the mass ratio of the phosphazene compound, ammonium polyphosphate and starch is 1:2:1.

[0087] Synthesis of phosphazene compounds: Hexachlorocyclotriphosphazene and melamine (molar ratio of 1:2) are refluxed in a pyridine solution (the mass concentration of hexachlorocyclotriphosphazene in the pyridine solution is 30%) at 100°C for 12 hours for nucleophilic substitution. After centrifugal drying, a phosphazene compound is obtained as a gas source and acid source for an intumescent flame retardant.

[0088] The modified glass powder is glass powder with melting points of 350° C., 500° C., and 700° C. (mass ratio 1:1:1) and is modified with silane according to the method in Example 1.

[0089] The preparation process of environmentally friendly silicone intumescent fire retardant coating for substation or converter station is as follows:

[0090] (1) Grinding an intumescent flame retardant, modified glass powder, and talcum powder, sieving, and ball milling for 30 minutes to obtain a composite filler;

[0091] (2) preparing a 40% by mass fraction SJ-804 epoxy modified silicone resin aqueous solution, adding the composite filler and polyester phosphate ester 5063A adhesion promoter in step (1), and stirring at 50° C. for 60 min;

[0092] (3) Add polyurethane curing agent and stir for 30 minutes to obtain a uniformly mixed organic silicon intumescent fire retardant coating, and apply the coating by brush. The substrate is stainless steel, and the coating thickness is 4 mm.

[0093] Example 4

[0094] The invention discloses an environmentally friendly organic silicon intumescent fire retardant coating for a transformer substation or a converter station. The raw materials thereof include, by weight, 35 parts of SJ-804 epoxy modified organic silicon resin, 45 parts of intumescent flame retardant, 5 parts of modified glass powder, 5 parts of nano titanium dioxide, 2 parts of talcum powder, 2 parts of polyester phosphate 5063A adhesion promoter, and 6 parts of polyurethane curing agent.

[0095] The intumescent flame retardant is a phosphazene compound as a gas source and an acid source, pentaerythritol as a carbon source, and the mass ratio of the phosphazene compound to the pentaerythritol is 4:1. The preparation process of the phosphazene compound is as described in Example 1.

[0096] The modified glass powder is glass powder with melting points of 350° C., 500° C., and 700° C. (mass ratio 1:1:1) and is modified with silane according to the method in Example 1.

[0097] The preparation process of environmentally friendly silicone intumescent fire retardant coating for substation or converter station is as follows:

[0098] (1) Grinding an intumescent flame retardant, modified glass powder, nano titanium dioxide, and talcum powder, sieving, and ball milling for 30 minutes to obtain a composite filler;

[0099] (2) preparing a 35% by mass SJ-804 epoxy modified silicone resin aqueous solution, adding the composite filler and polyester phosphate ester 5063A adhesion promoter in step (1), and stirring at 50° C. for 60 min;

[0100] (3) Add polyurethane curing agent and stir for 30 minutes to obtain a uniformly mixed organic silicon intumescent fire retardant coating, and apply the coating by brush. The substrate is stainless steel, and the coating thickness is 4 mm.

[0101] Comparative Example 1

[0102] A silicone fire retardant coating, which differs from Example 1 only in that the mass ratio of each raw material is changed. The raw materials include 65 parts of SJ-804 epoxy modified silicone resin, 25 parts of intumescent flame retardant, 4 parts of modified glass powder, 2 parts of talcum powder, 4 parts of polyester phosphate 5063A adhesion promoter, and 15 parts of polyurethane curing agent in parts by mass.

[0103] The preparation process of the organic silicon fire retardant coating is the same as that in Example 1, except that the corresponding parameters are changed. The substrate is stainless steel, and the coating thickness is 3 mm.

[0104] Comparative Example 2

[0105] A silicone fire retardant coating, which differs from Example 4 only in that the mass ratio of each raw material is changed: the raw materials include 25 parts of SJ-804 epoxy modified silicone resin, 50 parts of intumescent flame retardant, 12 parts of modified glass powder, 12 parts of nano titanium dioxide, 8 parts of talcum powder, 10 parts of polyester phosphate 5063A adhesion promoter, and 5 parts of polyurethane curing agent in parts by mass; the rest are the same as Example 4.

[0106] The preparation process of the organic silicon fire retardant coating is as described in Example 4 above, with the corresponding parameters changed. The substrate is stainless steel, and the coating thickness is 4 mm. The coating adhesion is very poor, the coating cracks, and the slag falls off. Figure 8 shown.

[0107] Comparative Example 3

[0108] This comparative example is a silicone resin coating containing uncompounded glass powder, and the only difference from Example 1 is that glass powder with a melting point of 350°C is used to replace the glass powders with melting points of 350°C, 500°C, and 700°C in Example 1. In the specific preparation process of the modified glass powder, the glass powder with a melting point of 350°C is ground, sieved and ball-milled for 30 minutes, and the remaining steps are the same as in Example 1.

[0109] Comparative Example 4

[0110] This comparative example is a silicone resin coating containing uncompounded glass powder, and the only difference from Example 1 is that glass powder with a melting point of 500°C is used to replace the glass powders with melting points of 350°C, 500°C, and 700°C in Example 1. In the specific preparation process of the modified glass powder, the glass powder with a melting point of 500°C is ground, sieved and ball-milled for 30 minutes, and the remaining steps are the same as in Example 1.

[0111] Comparative Example 5

[0112] This comparative example is a silicone resin coating containing uncompounded glass powder, and the only difference from Example 1 is that glass powder with a melting point of 700°C is used to replace the glass powders with melting points of 350°C, 500°C, and 700°C in Example 1; in the specific preparation process of the modified glass powder, the glass powder with a melting point of 700°C is ground, sieved, and ball-milled for 30 minutes, and the remaining steps are the same as in Example 1.

[0113] Comparative Example 6

[0114] This comparative example is a silicone resin coating with an intumescent flame retardant added alone, and the only difference from Example 1 is that no modified glass powder is added: its raw materials include 40 parts of SJ-804 epoxy modified silicone resin, 48 parts of intumescent flame retardant, 5 parts of talcum powder, 4 parts of polyester phosphate 5063A adhesion promoter, and 10 parts of polyurethane curing agent in terms of mass parts. The remaining steps are the same as Example 1.

[0115] Comparative Example 7

[0116] This comparative example is a silicone resin coating with modified glass powder added alone, and the only difference from Example 1 is that the raw materials include 40 parts of SJ-804 epoxy modified silicone resin, 48 parts of modified glass powder, 5 parts of talcum powder, 4 parts of polyester phosphate 5063A adhesion promoter, and 10 parts of polyurethane curing agent in terms of mass parts. The remaining steps are the same as Example 1.

[0117] The organic silicon intumescent fire retardant coatings obtained in Examples 1-4 were compared with the organic silicon coatings obtained in Comparative Examples 1-7. An acetylene burner was used to provide a stable fire source at 1200°C. The coatings were applied to a stainless steel substrate. A thermocouple was used to record the back temperature of the plate after burning the 11 coatings at 1200°C for 60 minutes. The relevant data obtained are shown in Tables 1 and Figure 5 and Fig. 9 shown.

[0118] Table 1 Backside temperature of eleven silicone flame retardant coatings

[0119]

[0120] Among them, in Comparative Example 2 in the table, since the paint fell off during the burning process, there was no stable temperature and carbon layer expansion multiple on the back side, which was expressed as / ; since the blank sample surface was not coated with paint, there was no carbon layer expansion multiple, and the carbon layer expansion multiple was expressed as / .

[0121] From Table 1 and Figure 7 It can be seen that the carbon layer of the organic silicon coating with the addition of intumescent flame retardant and glass powder expands, and the back temperature is significantly lower than that of the control. In the range of 300-500℃, the intumescent flame retardant pyrolyzes to generate a large amount of gas, and the carbon source expands the carbon layer under the action of the gas; the compounded glass powder melts and forms a secondary film in different temperature ranges to repair the cracks generated when the organic silicon resin is filled at high temperature.

[0122] Figure 1 This is the infrared spectrum of the phosphazene compound of Example 1. It can be seen that the infrared absorption of the P=N and PN bonds in the phosphazene compound is located at 1214 cm -1 and 870cm -1 Nearby, the stretching vibration peaks of CN and C=N of the triazine ring structure in the phosphazene compound are 1673 cm -1 and 1508cm -1 These infrared characteristics indicate that the phosphazene compound was successfully prepared.

[0123] Figure 2This is the XRD spectrum of the phosphazene compound of Example 1. It can be seen that compared with the raw materials melamine and hexachlorocyclotriphosphazene, after the copolymerization of melamine and hexachlorocyclotriphosphazene, the structural regularity and orderliness of the phosphazene compound are reduced, and the crystal diffraction of the phosphazene compound is located near 27°, which is an amorphous crystalline state.

[0124] Figure 3 This is the thermogravimetric curve of the phosphazene compound of Example 1. The temperatures at which the phosphazene compound loses 5 wt% of its weight under nitrogen and air are 323.0°C and 351.0°C, respectively. The pyrolysis range is consistent with the gas source and acid source in the intumescent flame retardant system.

[0125] Figure 4 This is a scanning electron microscope image of the phosphazene compound of Example 1, from which it can be seen that the microscopic morphology of the phosphazene compound is solid particles of 1-2 μm.

[0126] Figure 5 The back temperature test diagram of the organic silicon intumescent fire retardant coating prepared in Examples 1-4. The back temperature curve represents the back temperature at the center of the coating exposed to fire. The central stable temperature of the back of the coating in Examples 1-4 was all below 300°C.

[0127] Figure 6 The organic silicon intumescent fire retardant coating (left picture) and the digital picture of the carbon layer (right picture) prepared in Example 1. The surface of the coating is dense and crack-free, and the carbon layer is white due to the presence of glass powder.

[0128] Figure 7 This is a scan of the expanded carbon layer of the organic silicon intumescent fire retardant coating prepared in Example 2. The carbon layer of the coating is expanded and porous.

[0129] Figure 8 This is a digital image of the fire retardant coating prepared in Comparative Example 2, and the coating surface is powdering.

[0130] Fig. 9The back temperature test diagram of the organic silicon intumescent flame retardant fire retardant coating prepared in Comparative Examples 1-7. The blank sample is the back temperature of the substrate without coating. The back temperature results of Comparative Examples 1-7 are shown in Table 1. In Comparative Example 1, due to the increase in the mass fraction of the organic silicon resin film-forming agent, the mass fraction of the high temperature resistant components (intumescent flame retardant and modified glass powder) of the coating is low, and the high temperature resistance is worse than that of the embodiment. In Comparative Example 2, due to the reduction in the mass fraction of the organic silicon film-forming agent, the adhesion of the coating is reduced, and the coating falls off during the burning experiment. In comparative examples 3-5, the glass powder has a single melting point. When the melting point of the glass powder is 350°C, the glass powder melts too quickly, the coating melts through and cracks, and the high temperature resistance of the coating is reduced; when the melting point of the glass powder is 500°C, the starting temperature of the glass powder melt flow fails to cover the decomposition process of the intumescent flame retardant, resulting in cracks in the coating; when the melting point of the glass powder is 700°C, the temperature of the glass powder melt flow is too high, and the secondary film-forming effect after the decomposition of the silicone resin film-forming agent is not played. Therefore, the heat resistance of the coating containing the glass powder with a single melting point is worse than that of the compound glass powder. In comparative examples 6-7, the intumescent flame retardant is added alone, the carbon layer of the coating expands, the coating has better high temperature resistance, and the coating has fine cracks during the burning process. When the compound glass powder is added alone, the carbon layer of the coating has poor expansion effect, and the back temperature insulation effect is higher than 300°C. Therefore, under the joint action of the compound glass powder and the intumescent flame retardant, the high temperature insulation performance of the coating is significantly improved.

[0131] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. An environmentally friendly silicone intumescent fire retardant coating for a substation or a converter station, characterized in that: The raw materials include, by mass: 30-60 parts of organic silicone resin, 30-45 parts of intumescent flame retardant, 5-10 parts of modified glass powder, 2-20 parts of inorganic filler, 2-10 parts of auxiliary agent, and 5-25 parts of curing agent; The intumescent flame retardant uses a phosphazene compound as a gas source and an acid source; the phosphazene compound is formed by a nucleophilic substitution reaction between hexachlorocyclotriphosphazene and melamine or dicyandiamide; The modified glass powder is prepared by mixing a plurality of glass powders with melting points of 350° C. to 700° C. and then modifying them with a silane coupling agent.

2. The environmentally friendly organic silicon intumescent fire retardant coating for a transformer substation or a converter station according to claim 1, characterized in that: The organic silicon resin is an epoxy-modified organic silicon resin.

3. The environmentally friendly organic silicon intumescent fire retardant coating for a transformer substation or a converter station according to claim 1, characterized in that: The acid source of the intumescent flame retardant further comprises ammonium polyphosphate, ammonium polyphosphate or a mixture of the two.

4. The environmentally friendly organic silicon intumescent fire retardant coating for a transformer substation or a converter station according to claim 3, characterized in that: The mass ratio of ammonium polyphosphate, a mixture of one or both of ammonium polyphosphate and the phosphazene compound is 1-2:1-2.

5. The environmentally friendly organic silicon intumescent fire retardant coating for a transformer substation or a converter station according to claim 1, characterized in that: The carbon source of the intumescent flame retardant is a mixture of one or more of pentaerythritol, dipentaerythritol, starch and expanded graphite.

6. The environmentally friendly organic silicon intumescent fire retardant coating for a transformer substation or a converter station according to claim 1, characterized in that: The mass ratio of the phosphazene compound to the intumescent flame retardant carbon source is 1-4:

1.

7. The environmentally friendly organic silicon intumescent fire retardant coating for a transformer substation or a converter station according to claim 1, characterized in that: The modified glass powder is prepared by mixing three glass powders with melting points of 350° C., 500° C. and 700° C. and then modifying them with a silane coupling agent.

8. The environmentally friendly organic silicon intumescent fire retardant coating for a transformer substation or a converter station according to claim 7, characterized in that: The mass ratio of the three glass powders with melting points of 350°C, 500°C and 700°C is 1:1:

1.

9. The environmentally friendly organic silicon intumescent fire retardant coating for a transformer substation or a converter station according to claim 1, characterized in that: The preparation process of the modified glass powder comprises the following steps: grinding and sieving a plurality of glass powders with melting points of 350°C-700°C, mixing and ball milling, mixing with ethanol and water, adding a silane coupling agent, heating for reaction, and drying to obtain the modified glass powder.

10. The environmentally friendly organic silicon intumescent fire retardant coating for a transformer substation or a converter station according to claim 9, characterized in that: The reaction temperature was 60°C and the reaction time was 12 h.

11. The environmentally friendly organic silicon intumescent fire retardant coating for a transformer substation or a converter station according to claim 1, characterized in that: The silane coupling agent is an amino functional group silane coupling agent.

12. The environmentally friendly organic silicon intumescent fire retardant coating for a transformer substation or a converter station according to claim 1, characterized in that: The mass ratio of the silane coupling agent to the glass powder is 1:1-5.

13. The environmentally friendly organic silicon intumescent fire retardant coating for a transformer substation or a converter station according to claim 1, characterized in that: The inorganic filler is a mixture of one or more of talc, Mxene, graphene, expanded graphite, vermiculite, Al2O3, and nano titanium dioxide.

14. The environmentally friendly organic silicon intumescent fire retardant coating for a transformer substation or a converter station according to claim 1, characterized in that: The auxiliary agent is an adhesion promoter.

15. The environmentally friendly organic silicon intumescent fire retardant coating for a transformer substation or a converter station according to claim 14, characterized in that: The adhesion promoter includes a mixture of one or more of polyester phosphate 5063A adhesion promoter, 5140B water-based adhesion promoter, and AKN-6618 adhesion promoter.

16. The environmentally friendly organic silicon intumescent fire retardant coating for a transformer substation or converter station according to any one of claims 1 to 15, characterized in that: The curing agent is a mixture of one or more of polyurethane, amino compound and organic polysilazane.

17. A method for preparing an environmentally friendly organic silicon intumescent fire retardant coating for a transformer substation or a converter station as claimed in any one of claims 1 to 16, characterized in that: The method comprises the following steps: mixing an inorganic filler, an intumescent flame retardant and a modified glass powder by ball milling to obtain a composite filler; An organic silicon resin aqueous solution is prepared, and a composite filler and an auxiliary agent are added, and a curing agent is added and stirred after heating to obtain the environmentally friendly organic silicon intumescent fire retardant coating for a transformer substation or a converter station.

18. The method for preparing the environmentally friendly organic silicon intumescent fire retardant coating for a transformer substation or a converter station according to claim 17, characterized in that: The mass concentration of the organic silicon resin aqueous solution is 30-50%.

19. The method for preparing the environmentally friendly organic silicon intumescent fire retardant coating for a transformer substation or a converter station according to claim 17 or 18, characterized in that: Heat to 50°C and stir for 60 minutes before adding the curing agent.

20. A coating, characterized in that: The invention is prepared by using the environmentally friendly organic silicon intumescent fire retardant coating for a substation or a converter station as described in any one of claims 1 to 16.

21. Use of the environmentally friendly organic silicon intumescent fire retardant coating for a transformer substation or a converter station as claimed in any one of claims 1 to 16 in a transformer substation or a converter station.

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