Epoxy resin-based fireproof heat-insulating coating as well as preparation method and application thereof

Abstract

The invention discloses an epoxy resin-based fireproof heat-insulating coating as well as a preparation method and application thereof, and relates to the technical field of fireproof coatings. The epoxy resin-based fireproof heat-insulating coating prepared by the invention comprises an epoxy resin base material and modified ammonium polyphosphate, the epoxy resin base material is prepared by reacting epoxy resin with a hyperbranched block copolymer; hydroxyl hyperbranched polyethylene is used as an initiator and is subjected to chain extension with dihydroxyl-terminated poly (p-dioxanone) under the action of organic alkali, and thiophosphate triphenyl isocyanate is introduced, so that a hyperbranched block copolymer and epoxy resin form a stable cross-linked structure, the flame retardant property is improved, the thermal stability is ensured, and the flame retardant property is improved. The modified ammonium polyphosphate is prepared by coating the surface of ammonium polyphosphate with polyaldehyde polyester and polyamino polyether, so that the flame retardance and adhesive force of the coating are further improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of fireproof coating, in particular to an epoxy resin-based fireproof and heat-insulating coating as well as a preparation method and application thereof. BACKGROUND

[0002] Epoxy resin coating is a kind of high-performance coating with epoxy resin as the main film-forming material. Its core characteristics come from the epoxy groups and polar bonds in the molecular structure of epoxy resin, which form a three-dimensional network structure through cross-linking reaction with curing agents, giving the coating excellent adhesion, mechanical strength and chemical stability. Epoxy resin coating occupies an irreplaceable position in the fields of corrosion protection, insulation, fire prevention, etc., and has become the mainstream choice for industrial protection and functional coating.

[0003] Epoxy resin coating also has limitations. When used in the petroleum chemical and construction fields, it is prone to cracking under frequent impact, affecting the performance, and has high requirements for flame retardancy and adhesion. Therefore, the present application researches and prepares an epoxy resin-based fireproof and heat-insulating coating with high strength, flame retardancy and high adhesion to solve this problem. SUMMARY

[0004] The technical problem to be solved by the present application is to provide an epoxy resin-based fireproof and heat-insulating coating as well as a preparation method and application thereof.

[0005] A technical solution proposed by the present application to solve the above technical problem is an epoxy resin-based fireproof and heat-insulating coating, which comprises the following raw materials by weight: 20-30 parts of epoxy resin base material, 50-70 parts of flame retardant, 100-200 parts of expanded perlite, 2-4 parts of glass fiber, 10-30 parts of film-forming agent, 2-5 parts of curing agent, and 1-3 parts of defoaming agent. The epoxy resin base material is prepared by reacting epoxy resin with hyperbranched block copolymer. The flame retardant comprises modified ammonium polyphosphate and melamine in a mass ratio of 5:1-2.

[0006] Preferably, the hyperbranched block copolymer is prepared by reacting hydroxyl hyperbranched polyethylene, double-end hydroxyl poly-p-dioxanone and thiophosphoric acid triphenyl isocyanate.

[0007] Preferably, the modified ammonium polyphosphate is prepared by coating polyaldehyde polyester and polyamino polyether on the surface of ammonium polyphosphate. The polyaldehyde polyester is prepared by reacting hydroxyl-terminated hyperbranched polyester with aldehyde polyacrylic acid. The aldehyde polyacrylic acid is prepared by polymerizing acrylic acid and acrolein. The polyamino polyether is prepared by reacting epoxy chloropropane, dodecanol polyether and ammonia.

[0008] Preferably, the film-forming agent is alcohol ester twelve, the curing agent is polyamide, and the defoaming agent is nonylphenol polyoxyethylene ether.

[0009] Preferably, the preparation method of the epoxy resin-based fireproof and thermal insulation coating comprises the following specific steps: S1. Under a nitrogen atmosphere, mix the hydroxyl hyperbranched polyethylene, the double-end hydroxyl poly-p-dioxanone and the tetrahydrofuran at a mass ratio of 0.6:(0.4-0.6):3, stir uniformly, then add a tetrahydrofuran solution of dibutyltin dilaurate with a mass fraction of 3-5% at a rate of 1-3 ml / min, the mass fraction being 0.08-0.1 times the mass of the hydroxyl hyperbranched polyethylene, continue stirring for 15-20 min, add triphenylphosphine isocyanate thio-phosphate with a mass of 0.4-0.6 times the mass of the hydroxyl hyperbranched polyethylene, heat to 60-80℃, react for 6-7 h, quench with glacial acetic acid, then precipitate with methanol, extract and wash with methanol for 3-5 times, and dry at 60-70℃ under vacuum to obtain the hyperbranched block copolymer; S2. Mix the epoxy resin and the hyperbranched block copolymer at a mass ratio of 10:1-3, heat to 60-80℃, stir and mix at 400-600 rpm for 30-40 min, cool to 48-52℃, add the curing agent methyl hexahydrophthalic anhydride with a mass of 6-7 times the mass of the epoxy resin, continue stirring and reacting for 8-15 min, then add the accelerator 2,4,6-tris(dimethylaminomethyl)phenol with a mass of 0.01-0.03 times the mass of the epoxy resin, continue stirring and reacting for 8-10 min, vacuum degassing, heat to 80-82℃, react for 2-3 h, heat to 120-122℃, continue reacting for 2 h, heat to 50-52℃, and continue reacting for 1-2 h to obtain the epoxy resin base material; S3. Mix the aldehyde-based polyacrylic acid, ethylene glycol, p-toluenesulfonic acid and dimethyl sulfoxide at a mass ratio of 2:(1-2):(0.02-0.03):(4-5), heat to 58-62℃, react for 2-3 h, add the hydroxyl-terminated hyperbranched polyester with a mass of 1.1-1.2 times the mass of the aldehyde-based polyacrylic acid, and the catalyst 4-dimethylaminopyridine with a mass of 0.001-0.002 times the mass of the aldehyde-based polyacrylic acid, cool to 48-52℃, add the dimethyl sulfoxide solution of N,N'-dicyclohexyl carbodiimide with a mass fraction of 30-50% at a rate of 1-3 ml / min, the mass fraction being 0.22-0.24 times the mass of the aldehyde-based polyacrylic acid, heat to 78-82℃, react for 8-9 h, add the hydrochloric acid with a mass fraction of 0.03-0.04% at a mass of 1-1.2 times the mass of the aldehyde-based polyacrylic acid, cool to 38-42℃, react for 3-4 h, dialyze and freeze-dry at -40--60℃ to obtain the polyaldehyde-based polyester; S4. Ammonium polyphosphate, ethanol and deionized water are mixed in a mass ratio of 1: (2-3) : 1, and ultrasonic treatment is performed at 40-60 kHz for 20-30 min. Polyformal polyester is added in an amount of 0.2-0.3 times the mass of the ammonium polyphosphate, and the temperature is raised to 60-62℃. Reaction is performed for 6-8 h, and then polyamino polyether is added in an amount of 0.1-0.2 times the mass of the ammonium polyphosphate, and a catalyst, p-toluenesulfonic acid, is added in an amount of 0.005-0.007 times the mass of the ammonium polyphosphate. The temperature is raised to 80-82℃, and reaction is performed for 8-10 h. After cooling, centrifugation is performed, and washing is performed 3-5 times with ethanol. Vacuum drying is performed at 60-70℃, and modified ammonium polyphosphate is obtained. S5. Modified ammonium polyphosphate and melamine are mixed in a weight ratio to obtain a flame retardant. An epoxy resin base is mixed with a film-forming agent and added to a reaction kettle. Stirring is performed at 600-800 rpm for 8-10 min, and the temperature is raised to 50-60℃. The flame retardant is added, and dispersion is performed at 1000-2000 rpm for 20-30 min. Intumescent perlite and glass fibers are added, and stirring is performed at 300-500 rpm for 10-13 min. Defoaming agent and curing agent are added, and stirring is continued for 5-8 min. Vacuum degassing is performed, and an epoxy resin-based fireproof and heat-insulating coating is obtained.

[0010] Preferably, in step S1, the method for preparing the hydroxyl hyperbranched polyethylene is as follows: ethylene, hydroxyethyl acrylate, a catalyst, nickel bromide di-(2,6-dimethylphenyl) hexanediamine, and toluene are mixed in a mass ratio of 1: (0.08-0.14) : (0.002-0.004) : (3-5), the temperature is raised to 30-40℃, the pressure is 0.5-1.5 MPa, and reaction is performed for 2-6 h. An ethanol solution of sodium hydroxide with a mass fraction of 20-25% is added in an amount of 20-30 times the mass of the ethylene, and reaction is continued for 30-50 min. Filtration is performed, and washing is performed 3-5 times with methanol and deionized water, respectively. Vacuum drying is performed at 60-80℃, and hydroxyl hyperbranched polyethylene is obtained.

[0011] Preferably, in step S1, the method for preparing the hydroxyl hyperbranched polyethylene is as follows: ethylene, hydroxyethyl acrylate, a catalyst, nickel bromide di-(2,6-dimethylphenyl) hexanediamine, and toluene are mixed in a mass ratio of 1: (0.08-0.14) : (0.002-0.004) : (3-5), the temperature is raised to 30-40℃, the pressure is 0.5-1.5 MPa, and reaction is performed for 2-6 h. An ethanol solution of sodium hydroxide with a mass fraction of 20-25% is added in an amount of 20-30 times the mass of the ethylene, and reaction is continued for 30-50 min. Filtration is performed, and washing is performed 3-5 times with methanol and deionized water, respectively. Vacuum drying is performed at 60-80℃, and hydroxyl hyperbranched polyethylene is obtained.

[0012] Preferably, in step S1, the preparation method of the aldehyde group polyacrylic acid is as follows: under a nitrogen atmosphere, acrylic acid and deionized water are mixed at a mass ratio of 1:1-2, stirred and dissolved, and then the pH is adjusted to 6.5-7.5 by using 30% sodium hydroxide; acrylic aldehyde is added in an amount of 0.4-0.8 times the mass of the acrylic acid, and ammonium persulfate is added in an amount of 0.01-0.03 times the mass of the acrylic acid; the temperature is raised to 50-60 DEG C, and the reaction is carried out for 8-12 hours; the pH is adjusted to 2.0-2.2 by using hydrochloric acid; then the product is precipitated by using acetone; after being dissolved in deionized water, the product is precipitated again by using acetone; finally, the product is vacuum dried at 40-50 DEG C to obtain the aldehyde group polyacrylic acid.

[0013] Preferably, in step S3, the preparation method of the polyamino polyether is as follows: under a nitrogen atmosphere, dodecanol polyether and DMC catalyst are mixed at a mass ratio of 10:0.1-0.2, the temperature is raised to 115-120 DEG C, and dodecanol polyether is added dropwise at a rate of 1-3 ml / min, in an amount of 1-2 times the mass of the dodecanol polyether; the temperature is raised to 125-135 DEG C, and the reaction is carried out for 5-6 hours; after being distilled under reduced pressure, 25-28% ammonia water is added in an amount of 2-3 times the mass of the dodecanol polyether, and toluene is added in an amount of 0.4-0.6 times the mass of the dodecanol polyether; the temperature is raised to 50-52 DEG C, and the reaction is carried out for 3-4 hours; the product is separated and washed with deionized water for 3-5 times; and the product is obtained by rotary evaporation.

[0014] Preferably, the epoxy resin-based fireproof and thermal insulation coating is applied in the fields of petrochemical industry and construction.

[0015] Compared with the prior art, the present application has the following beneficial effects: The epoxy resin-based fireproof and thermal insulation coating prepared by the present application comprises an epoxy resin base and modified ammonium polyphosphate; the epoxy resin base is prepared by reacting an epoxy resin with a hyperbranched block copolymer; The hyperbranched block copolymer is prepared by reacting hydroxyl hyperbranched polyethylene, dihydroxyl poly-p-dioxanone and thiophosphoric acid triphenyl isocyanate; the hydroxyl hyperbranched polyethylene is used as an initiator, and the dihydroxyl poly-p-dioxanone is introduced under the action of an organic base; at the same time, thiophosphoric acid triphenyl isocyanate is introduced for chain extension; the hyperbranched block copolymer forms a stable crosslinking structure with the epoxy resin, which improves the flame retardant performance and guarantees the thermal stability; the introduction of the thiophosphoric acid triphenyl isocyanate for chain extension generates urethane bonds and a covalent network formed by the ring opening of epoxy groups, which further improves the adhesion between the coating and the substrate; The modified ammonium polyphosphate is prepared by coating the surface of ammonium polyphosphate with polyaldehyde polyester and polyamino polyether; the polyaldehyde polyester is prepared by reacting hydroxyl-terminated hyperbranched polyester with aldehyde polyacrylic acid, the aldehyde polyacrylic acid is prepared by polymerizing acrylic acid and propyl aldehyde, and the polyamino polyether is prepared by reacting epoxy chloropropane, dodecanol polyether and ammonia; the polyaldehyde polyester and the polyamino polyether form a stable cross-linked network on the surface of the ammonium polyphosphate, further improving the flame retardance and adhesion of the coating. DETAILED DESCRIPTION

[0016] The present application will be described in detail below by way of examples. It is necessary to point out here that the following examples are only used to further illustrate the present application and cannot be understood as limiting the scope of protection of the present application. Those skilled in the art can make some non-essential improvements and adjustments to the present application according to the above content of the present application. Unless otherwise defined, all professional and scientific terms used herein have the same meaning as familiar to those skilled in the art.

[0017] The epoxy resin in the present application is bisphenol A epoxy resin.

[0018] In order to more clearly illustrate the method provided by the present application, the following examples are used to illustrate in detail, and the index test method of the epoxy resin-based fireproof and heat-insulating coating prepared in the examples and comparative examples is as follows: Oxygen index: the epoxy resin-based fireproof and heat-insulating coating is sprayed on the surface of tinplate, and cured at 120℃ for 5h, the coating thickness is 40μm, and the oxygen index test is carried out according to GB / T2406.

[0019] Impact strength: the epoxy resin-based fireproof and heat-insulating coating is placed in a mold, and cured at 120℃ for 5h, the coating thickness is 40μm, and the impact strength test is carried out according to GB / T2567.

[0020] Thermal stability: the epoxy resin-based fireproof and heat-insulating coating is sprayed on the surface of tinplate, and cured at 120℃ for 5h, the coating thickness is 40μm, and the glass transition temperature test is carried out according to GB / T19466.

[0021] Adhesion: the epoxy resin-based fireproof and heat-insulating coating is sprayed on the surface of steel, and cured at 120℃ for 5h, the coating thickness is 40μm, and the maximum tensile force at break is tested according to GB / T5210.

[0022] Example 1

[0023] In the present example, the components and weight fractions of the epoxy resin-based fireproof and heat-insulating coating are as follows: 20 parts of epoxy resin base material, 50 parts of flame retardant, 100 parts of expanded perlite, 2 parts of glass fiber, 10 parts of film-forming agent alcohol ester twelve, 2 parts of curing agent polyamide, 1 part of defoaming agent nonyl phenol polyoxyethylene ether, and the flame retardant includes modified ammonium polyphosphate and melamine with a mass ratio of 5:1.

[0024] The preparation method of the epoxy resin-based fireproof and thermal insulation coating in this embodiment is as follows: S1. Under a nitrogen atmosphere, ethylene, hydroxyethyl acrylate, a catalyst, nickel bis-(2,6-dimethylphenyl) hexanediamine bromide, and toluene were mixed in a mass ratio of 1:0.08:0.002:3, and the temperature was raised to 30°C under a pressure of 0.5 MPa. The reaction was continued for 2 h, and then 20 times the mass of ethylene of a 20% mass fraction sodium hydroxide ethanol solution was added, and the reaction was continued for 30 min. Filtration was performed, and the product was washed with methanol and deionized water three times in sequence, and then vacuum drying was performed at 60°C to obtain a hydroxyl hyperbranched polyethylene. Under a nitrogen atmosphere, p-dioxanone and butanediol were mixed in a mass ratio of 20:1, and the temperature was raised to 80°C. After uniform stirring, 0.3 times the mass of p-dioxanone of a 2% mass fraction stannous octoate catalyst toluene solution was added, and the reaction was continued for 48 h. The product was cooled to room temperature and then crushed to obtain a double-end hydroxyl poly-p-dioxanone. Under a nitrogen atmosphere, the hydroxyl hyperbranched polyethylene, the double-end hydroxyl poly-p-dioxanone, and tetrahydrofuran were mixed in a mass ratio of 0.6:0.4:3, and uniform stirring was performed. Then, 0.08 times the mass of the hydroxyl hyperbranched polyethylene of a 3% mass fraction dibutyltin dilaurate tetrahydrofuran solution was added dropwise at a rate of 1 ml / min, and the stirring was continued for 15 min. Then, 0.4 times the mass of the hydroxyl hyperbranched polyethylene of triphenylphosphine isocyanate was added, the temperature was raised to 60°C, and the reaction was continued for 6 h. The reaction was quenched with glacial acetic acid, and then the product was precipitated with methanol, filtered, and washed with methanol three times. Vacuum drying was performed at 60°C to obtain a hyperbranched block copolymer; S2. The epoxy resin and the hyperbranched block copolymer were mixed in a mass ratio of 10:1, and the temperature was raised to 60°C. The mixture was stirred at 400 rpm for 30 min, and then the temperature was lowered to 48°C. 6 times the mass of the epoxy resin of a curing agent, methyl hexahydrophthalic anhydride, was added, and the stirring was continued for 8 min. Then, 0.01 times the mass of the epoxy resin of a promoter, 2,4,6-tris(dimethylaminomethyl)phenol, was added, and the stirring was continued for 8 min. Vacuum degassing was performed, and the temperature was raised to 80°C. The reaction was continued for 2 h, and then the temperature was raised to 120°C. The reaction was continued for 2 h, and then the temperature was raised to 50°C. The reaction was continued for 1 h to obtain an epoxy resin base material. S3. Under nitrogen atmosphere, acrylic acid and deionized water were mixed in a mass ratio of 1:1, stirred and dissolved, and then the pH was adjusted to 6.5 with 30% sodium hydroxide. Acrolein was added in an amount of 0.4 times the mass of the acrylic acid, and ammonium persulfate was added in an amount of 0.01 times the mass of the acrylic acid. The temperature was raised to 50°C, and the reaction was carried out for 8 hours. The pH was adjusted to 2.0 with hydrochloric acid, and then the product was precipitated with acetone. After being dissolved in deionized water, it was precipitated again with acetone. Finally, it was vacuum dried at 40°C to obtain aldehyde-functionalized polyacrylic acid. The aldehyde-functionalized polyacrylic acid, ethylene glycol, p-toluenesulfonic acid, and dimethyl sulfoxide were mixed in a mass ratio of 2:1:0.02:4. The temperature was raised to 58°C, and the reaction was carried out for 2 hours. Hydroxyl-terminated hyperbranched polyester was added in an amount of 1.1 times the mass of the aldehyde-functionalized polyacrylic acid, and 4-dimethylaminopyridine was added as a catalyst in an amount of 0.001 times the mass of the aldehyde-functionalized polyacrylic acid. The temperature was lowered to 48°C, and a solution of N,N'-dicyclohexyl carbodiimide in dimethyl sulfoxide with a mass fraction of 30% was added dropwise at a rate of 1 ml / min, in an amount of 0.22 times the mass of the aldehyde-functionalized polyacrylic acid. The temperature was raised to 78°C, and the reaction was carried out for 8 hours. Hydrochloric acid with a mass fraction of 0.03% was added in an amount of 1 times the mass of the aldehyde-functionalized polyacrylic acid, and the temperature was lowered to 38°C. The reaction was carried out for 3 hours. The product was dialyzed and freeze-dried at -40°C to obtain polyaldehyde-functionalized polyester; S4. Under nitrogen atmosphere, dodecanol polyether and DMC catalyst were mixed in a mass ratio of 10:0.1. The temperature was raised to 115°C, and epoxidized chloropropane with a mass fraction of 25% was added dropwise at a rate of 1 ml / min, in an amount of 1 times the mass of the dodecanol polyether. The temperature was raised to 125°C, and the reaction was carried out for 5 hours. After vacuum distillation, ammonia water with a mass fraction of 25% was added in an amount of 2 times the mass of the dodecanol polyether, and toluene was added in an amount of 0.4 times the mass of the dodecanol polyether. The temperature was raised to 50°C, and the reaction was carried out for 3 hours. The product was separated and washed with deionized water 3 times. Vacuum distillation was carried out to obtain polyamino polyether. Ammonium polyphosphate, ethanol, and deionized water were mixed in a mass ratio of 1:2:1, and ultrasonic treatment was carried out at 40 kHz for 20 minutes. Polyaldehyde-functionalized polyester was added in an amount of 0.2 times the mass of the ammonium polyphosphate. The temperature was raised to 60°C, and the reaction was carried out for 6 hours. Polyamino polyether was added in an amount of 0.1 times the mass of the ammonium polyphosphate, and p-toluenesulfonic acid was added as a catalyst in an amount of 0.005 times the mass of the ammonium polyphosphate. The temperature was raised to 80°C, and the reaction was carried out for 8 hours. After cooling, the product was centrifuged and washed with ethanol 3 times. Vacuum drying was carried out at 60°C to obtain modified ammonium polyphosphate. S5. Modified ammonium polyphosphate and melamine were mixed in a weight ratio to obtain a flame retardant. An epoxy resin base and a film-forming agent were mixed and added to a reaction kettle. Stirring was carried out at 600 rpm for 8 minutes. The temperature was raised to 50°C. The flame retardant was added and dispersed at 1000 rpm for 20 minutes. Intumescent perlite and glass fiber were added, and stirring was carried out at 300 rpm for 10 minutes. Defoaming agent and curing agent were added, and stirring was continued for 5 minutes. Vacuum degassing was carried out to obtain an epoxy resin-based fireproof and heat-insulating coating.

[0025] Example 2

[0026] The components and weight fractions of the epoxy resin-based fireproof thermal insulation coating in this embodiment are as follows: 25 parts of epoxy resin base material, 60 parts of flame retardant, 150 parts of expanded perlite, 3 parts of glass fiber, 20 parts of film-forming agent alcohol ester twelve, 4 parts of curing agent polyamide, and 2 parts of defoaming agent nonyl phenol polyoxyethylene ether. The flame retardant includes modified polyammonium phosphate and melamine in a mass ratio of 5:1.5.

[0027] The preparation method of the epoxy resin-based fireproof thermal insulation coating in this embodiment is as follows: S1. Under a nitrogen atmosphere, ethylene, hydroxyethyl acrylate, catalyst nickel bromide di-(2,6-dimethylphenyl) hexanediamine, and toluene are mixed in a mass ratio of 1:0.11:0.003:4, heated to 35℃, the pressure is 1.0 MPa, and the reaction is carried out for 4 h. Then, 25 times the mass of ethylene of a 23% mass fraction sodium hydroxide ethanol solution is added, and the reaction is continued for 40 min. After filtration and washing with methanol and deionized water four times in sequence, vacuum drying is carried out at 70℃ to obtain hydroxyl hyperbranched polyethylene. Under a nitrogen atmosphere, p-dioxanone and butanediol are mixed in a mass ratio of 30:2, heated to 105℃, and stirred uniformly. Then, 0.45 times the mass of p-dioxanone of a 3% mass fraction stannous octoate catalyst toluene solution is added, and the reaction is carried out for 64 h. After cooling to room temperature, the product is crushed to obtain double-end hydroxyl poly-p-dioxanone. Under a nitrogen atmosphere, hydroxyl hyperbranched polyethylene, double-end hydroxyl poly-p-dioxanone, and tetrahydrofuran are mixed in a mass ratio of 0.6:0.5:3, and stirred uniformly. Then, 0.09 times the mass of hydroxyl hyperbranched polyethylene of a 4% mass fraction dibutyltin dilaurate tetrahydrofuran solution is added at a rate of 2 ml / min, and the stirring reaction is continued for 17 min. Then, 0.5 times the mass of hydroxyl hyperbranched polyethylene of triphenyl phosphite isocyanate is added, heated to 70℃, and the reaction is carried out for 6.5 h. After quenching with glacial acetic acid, precipitation is carried out with methanol, filtration and washing with methanol four times, and vacuum drying at 65℃, a hyperbranched block copolymer is obtained; S2. Epoxy resin and the hyperbranched block copolymer are mixed in a mass ratio of 10:2, heated to 70℃, and stirred at 500 rpm for 35 min. Then, 6.5 times the mass of epoxy resin of a curing agent methyl hexahydrophthalic anhydride is added, and the stirring reaction is continued for 12 min. Then, 0.02 times the mass of epoxy resin of a promoter 2,4,6-tris(dimethylaminomethyl) phenol is added, and the stirring reaction is continued for 9 min. After vacuum degassing, the temperature is raised to 81℃, and the reaction is carried out for 2.5 h. Then, the temperature is raised to 121℃, and the reaction is continued for 2 h. Then, the temperature is raised to 51℃, and the reaction is continued for 1.5 h to obtain an epoxy resin base material. S3. Under a nitrogen atmosphere, acrylic acid and deionized water were mixed in a mass ratio of 1:1.5, stirred and dissolved, and the pH was adjusted to 7.0 with 30% sodium hydroxide. Acrolein (0.6 times the mass of acrylic acid) and ammonium persulfate (0.02 times the mass of acrylic acid) were added, and the temperature was raised to 55°C for 10 hours. The pH was adjusted to 2.1 with hydrochloric acid, and the mixture was precipitated with acetone. After dissolving in deionized water, the mixture was precipitated with acetone again, and finally dried in a vacuum at 45°C to obtain formaldehyde-modified polyacrylic acid. Formaldehyde-modified polyacrylic acid, ethylene glycol, p-toluenesulfonic acid, and dimethyl sulfoxide were mixed in a mass ratio of 2:1.5:0.025:4.5, and the temperature was raised to 60°C. , react for 2.5 hours, add hydroxyl-terminated hyperbranched polyester with a mass fraction of 1.15 times that of formaldehyde-modified polyacrylic acid and catalyst 4-dimethylaminopyridine with a mass fraction of 0.0015 times that of formaldehyde-modified polyacrylic acid, cool to 50°C, add 40% N,N'-dicyclohexylcarbodiimide in dimethyl sulfoxide with a mass fraction of 0.23 times that of formaldehyde-modified polyacrylic acid at a rate of 2 ml / min, heat to 80°C, react for 8.5 hours, add 0.035% hydrochloric acid with a mass fraction of 1.1 times that of formaldehyde-modified polyacrylic acid, cool to 40°C, react for 3.5 hours, dialyze and freeze-dry at -50°C to obtain a polyaldehyde-modified polyester; S4. Under a nitrogen atmosphere, dodecanol polyether and DMC catalyst were mixed in a mass ratio of 10:0.15, heated to 118 ° C, and epichlorohydrin (1.5 times the mass of dodecanol polyether) was added dropwise at a rate of 2 ml / min, heated to 130 ° C, reacted for 5.5 h, and after reduced pressure distillation, 2.5 times the mass of dodecanol polyether with a 26% ammonia solution and 0.5 times the mass of dodecanol polyether with toluene were added, heated to 51 ° C, reacted for 3.5 h, separated and washed with deionized water 4 times, and rotary evaporated. preparing polyamino polyether; ammonium polyphosphate, ethanol and deionized water in a mass ratio of 1:2.5:1, ultrasonically treating at 50kHz for 25 minutes, adding 0.25 times the mass of polyaldehyde polyester of ammonium polyphosphate, heating to 61°C, reacting for 7 hours, then adding 0.15 times the mass of polyamino polyether of ammonium polyphosphate and 0.006 times the mass of ammonium polyphosphate as a catalyst p-toluenesulfonic acid, heating to 81°C, reacting for 9 hours, cooling and centrifuging, washing with ethanol four times, and vacuum drying at 65°C to prepare modified ammonium polyphosphate; S5. Modified ammonium polyphosphate and melamine were mixed by weight to prepare flame retardant; epoxy resin base material and film-forming agent were mixed and added to the reactor, stirred at 700 rpm for 9 minutes, heated to 55 ° C, flame retardant was added, dispersed at 1500 rpm for 25 minutes, expanded perlite and glass fiber were added, stirred at 400 rpm for 12 minutes, defoaming agent and curing agent were added, stirring was continued for 7 minutes, vacuum degassing was carried out to prepare epoxy resin-based fire retardant and heat-insulating coating.

[0028] Example 3

[0029] The components and weight fractions of the epoxy resin-based fireproof thermal insulation coating in this embodiment are: 30 parts of epoxy resin base material, 70 parts of flame retardant, 200 parts of expanded perlite, 4 parts of glass fiber, 30 parts of film-forming agent alcohol ester twelve, 5 parts of curing agent polyamide, 3 parts of defoaming agent nonyl phenol polyoxyethylene ether, and the flame retardant includes modified polyammonium phosphate and melamine with a mass ratio of 5:2.

[0030] The preparation method of the epoxy resin-based fireproof thermal insulation coating in this embodiment is: S1. Under a nitrogen atmosphere, ethylene, hydroxyethyl acrylate, catalyst nickel bromide di-(2,6-dimethylphenyl) hexanediamine, and toluene are mixed in a mass ratio of 1:0.14:0.004:5, heated to 40℃, the pressure is 1.5 MPa, and the reaction is carried out for 6 h. Then, 30 times the mass of ethylene of a 25% mass fraction sodium hydroxide ethanol solution is added, and the reaction is continued for 50 min. After filtration and washing with methanol and deionized water 5 times in sequence, vacuum drying is carried out at 80℃ to obtain hydroxyl hyperbranched polyethylene. Under a nitrogen atmosphere, p-dioxanone and butanediol are mixed in a mass ratio of 40:3, heated to 110℃, and stirred uniformly. Then, 0.6 times the mass of p-dioxanone of a 4% mass fraction stannous octoate catalyst toluene solution is added, and the reaction is carried out for 72 h. After cooling to room temperature, the product is crushed to obtain double-end hydroxyl poly-p-dioxanone. Under a nitrogen atmosphere, hydroxyl hyperbranched polyethylene, double-end hydroxyl poly-p-dioxanone, and tetrahydrofuran are mixed in a mass ratio of 0.6:0.6:3, and stirred uniformly. Then, 0.1 times the mass of hydroxyl hyperbranched polyethylene of a 5% mass fraction dibutyltin dilaurate tetrahydrofuran solution is added at a rate of 3 ml / min, and the stirring reaction is continued for 20 min. Then, 0.6 times the mass of hydroxyl hyperbranched polyethylene of triphenyl phosphite isocyanate is added, heated to 80℃, and the reaction is carried out for 7 h. After quenching with glacial acetic acid, the product is precipitated with methanol, filtered, washed with methanol 5 times, and vacuum dried at 70℃ to obtain a hyperbranched block copolymer; S2. Epoxy resin and hyperbranched block copolymer are mixed in a mass ratio of 10:3, heated to 80℃, and stirred at 600 rpm for 40 min. Then, the temperature is lowered to 52℃, 7 times the mass of epoxy resin of a curing agent methyl hexahydrophthalic anhydride is added, the stirring reaction is continued for 15 min, 0.03 times the mass of epoxy resin of a promoter 2,4,6-tris(dimethylaminomethyl) phenol is added, the stirring reaction is continued for 10 min, vacuum degassing is carried out, the temperature is raised to 82℃, the reaction is carried out for 3 h, the temperature is raised to 122℃, the reaction is continued for 2 h, the temperature is raised to 52℃, and the reaction is continued for 2 h to obtain an epoxy resin base material. S3. Under nitrogen atmosphere, acrylic acid and deionized water were mixed in a mass ratio of 1:2, stirred and dissolved, and then the pH was adjusted to 7.5 with 30% sodium hydroxide. Acrolein was added in an amount of 0.8 times the mass of the acrylic acid, and ammonium persulfate was added in an amount of 0.03 times the mass of the acrylic acid. The temperature was raised to 60°C, and the reaction was carried out for 12 hours. The pH was adjusted to 2.2 with hydrochloric acid, and then the product was precipitated with acetone. After being dissolved in deionized water, it was precipitated again with acetone. Finally, it was vacuum dried at 50°C to obtain aldehyde-functionalized polyacrylic acid. The aldehyde-functionalized polyacrylic acid, ethylene glycol, p-toluenesulfonic acid, and dimethyl sulfoxide were mixed in a mass ratio of 2:2:0.03:5, and the temperature was raised to 62°C. The reaction was carried out for 3 hours. Hydroxyl-terminated hyperbranched polyester was added in an amount of 1.2 times the mass of the aldehyde-functionalized polyacrylic acid, and 4-dimethylaminopyridine was added as a catalyst in an amount of 0.002 times the mass of the aldehyde-functionalized polyacrylic acid. The temperature was lowered to 52°C, and a solution of N,N'-dicyclohexyl carbodiimide in dimethyl sulfoxide with a mass fraction of 50% was added dropwise at a rate of 3 ml / min, in an amount of 0.24 times the mass of the aldehyde-functionalized polyacrylic acid. The temperature was raised to 82°C, and the reaction was carried out for 9 hours. Hydrochloric acid with a mass fraction of 0.04% was added in an amount of 1.2 times the mass of the aldehyde-functionalized polyacrylic acid, and the temperature was lowered to 42°C. The reaction was carried out for 4 hours. The product was dialyzed and freeze-dried at -60°C to obtain polyaldehyde-functionalized polyester; S4. Under nitrogen atmosphere, dodecanol polyether and DMC catalyst were mixed in a mass ratio of 10:0.2, and the temperature was raised to 120°C. Epichlorohydrin with a mass fraction of 2 times the mass of the dodecanol polyether was added dropwise at a rate of 3 ml / min, and the temperature was raised to 135°C. The reaction was carried out for 6 hours. After vacuum distillation, ammonia water with a mass fraction of 28% was added in an amount of 3 times the mass of the dodecanol polyether, and toluene was added in an amount of 0.6 times the mass of the dodecanol polyether. The temperature was raised to 52°C, and the reaction was carried out for 4 hours. The product was separated and washed with deionized water 5 times. Vacuum distillation was carried out to obtain polyamino polyether. Ammonium polyphosphate, ethanol, and deionized water were mixed in a mass ratio of 1:3:1, and ultrasonic treatment was carried out at 60 kHz for 30 min. Polyaldehyde-functionalized polyester was added in an amount of 0.3 times the mass of the ammonium polyphosphate, and the temperature was raised to 62°C. The reaction was carried out for 8 hours. Polyamino polyether was added in an amount of 0.2 times the mass of the ammonium polyphosphate, and p-toluenesulfonic acid was added as a catalyst in an amount of 0.007 times the mass of the ammonium polyphosphate. The temperature was raised to 82°C, and the reaction was carried out for 10 hours. After cooling, the product was centrifuged and washed with ethanol 5 times, and vacuum dried at 70°C to obtain modified ammonium polyphosphate; S5. Modified ammonium polyphosphate and melamine were mixed in a weight ratio of 1:1 to obtain a flame retardant. An epoxy resin base and a film-forming agent were mixed and added to a reaction kettle. The mixture was stirred at 800 rpm for 10 min, and the temperature was raised to 60°C. The flame retardant was added and dispersed at 2000 rpm for 30 min. Intumescent perlite and glass fiber were added, and the mixture was stirred at 500 rpm for 13 min. Defoaming agent and curing agent were added, and the mixture was continuously stirred for 8 min. Vacuum degassing was carried out to obtain an epoxy resin-based fireproof and heat-insulating coating.

[0031] Comparative Example 1 The preparation method of Comparative Example 1 is the same as that of Example 2. The difference between the epoxy resin-based fireproof thermal insulation coating and that of Example 2 is that the hyperbranched block copolymer is prepared by reacting hydroxyl hyperbranched polyethylene with triphenyl isocyanate phosphorothioate.

[0032] Comparative Example 2 The preparation method of Comparative Example 2 is the same as that of Example 2. The difference between the epoxy resin-based fireproof thermal insulation coating and that of Example 2 is that the hyperbranched block copolymer is prepared by reacting double-end hydroxyl poly-p-dioxanone with triphenyl isocyanate phosphorothioate.

[0033] Comparative Example 3 The preparation method of Comparative Example 3 is the same as that of Example 2. The difference between the epoxy resin-based fireproof thermal insulation coating and that of Example 2 is that the epoxy resin base material is only epoxy resin.

[0034] Comparative Example 4 The preparation method of Comparative Example 4 is the same as that of Example 2. The difference between the epoxy resin-based fireproof thermal insulation coating and that of Example 2 is that the modified ammonium polyphosphate is prepared by coating polyaldehyde polyester on the surface of ammonium polyphosphate.

[0035] Comparative Example 5 The preparation method of Comparative Example 5 is the same as that of Example 2. The difference between the epoxy resin-based fireproof thermal insulation coating and that of Example 2 is that the modified ammonium polyphosphate is prepared by coating polyamine polyether on the surface of ammonium polyphosphate.

[0036] Comparative Example 6 The preparation method of Comparative Example 6 is the same as that of Example 2. The difference between the epoxy resin-based fireproof thermal insulation coating and that of Example 2 is that the flame retardant only includes ammonium polyphosphate and melamine.

[0037] Effect Example Table 1 below is the performance test results of the epoxy resin-based fireproof thermal insulation coatings prepared in the examples and comparative examples; Table 1

[0038] As can be seen from the performance data in Table 1, the epoxy resin-based fireproof thermal insulation coating prepared by the present application not only has light quality, but also has excellent strength, thermal stability and adhesion; From the experimental data comparison of Example 1, Example 2, Example 3 and Comparative Example 1, Comparative Example 2, Comparative Example 3, it can be found that, under the action of organic base, the hydroxyl hyperbranched polyethylene as initiator is introduced into both ends of hydroxyl poly-p-dioxanone, and at the same time, the triphenyl isocyanate phosphorothioate is introduced for chain extension, so that the hyperbranched block copolymer forms a stable cross-linked structure with the epoxy resin, improves the flame retardant performance, at the same time, ensures the thermal stability, introduces the hyperbranched structure and flexible chain segment in the epoxy resin, improves the impact resistance and high strength of the coating; the urethane bond generated by introducing triphenyl isocyanate phosphorothioate for chain extension and the covalent network formed by the ring opening of epoxy group can further improve the adhesion of the coating to the substrate.

[0039] From the experimental data comparison of Example 1, Example 2, Example 3 and Comparative Example 4, Comparative Example 5, Comparative Example 6, it can be found that, the polyaldehyde polyester prepared by reacting the hydroxyl-terminated hyperbranched polyester with aldehyde-based polyacrylic acid, and the polyamino polyether prepared by reacting the epoxy chloropropane, dodecanol polyether and ammonia, form a stable cross-linked network on the surface of ammonium polyphosphate, further improve the flame retardant and adhesion of the coating, at the same time, enhance the hydrophobicity of the coating, and ensure the performance stability of the coating in a humid environment.

[0040] Obviously, the above embodiments are only examples for clearly illustrating the embodiments of the present application, and are not intended to limit the embodiments of the present application. For those skilled in the art, on the basis of the above description, other different forms of changes or variations can also be made. Here, it is not necessary and impossible to exhaust all the embodiments. These obvious changes or variations derived from the spirit of the present application are still within the protection scope of the present application.

Claims

1. An epoxy resin-based fireproof and heat-insulating coating, characterized in that: The invention comprises the following raw materials by weight: 20-30 parts of epoxy resin base material, 50-70 parts of flame retardant material, 100-200 parts of expanded perlite, 2-4 parts of glass fiber, 10-30 parts of film-forming agent, 2-5 parts of curing agent, and 1-3 parts of defoaming agent; the epoxy resin base material is prepared by reacting epoxy resin with a hyperbranched block copolymer; the flame retardant material comprises modified ammonium polyphosphate and melamine in a mass ratio of 5:1-2.

2. The epoxy resin-based fireproof and heat-insulating coating according to claim 1, characterized in that: The hyperbranched block copolymer is prepared by reacting hydroxy hyperbranched polyethylene, double-terminal hydroxy poly-p-dioxanone and triphenyl isocyanate thiophosphate.

3. The epoxy resin-based fireproof and heat-insulating coating according to claim 1, characterized in that: The modified ammonium polyphosphate is prepared by coating a polyaldehyde polyester and a polyamino polyether on the surface of the ammonium polyphosphate; the polyaldehyde polyester is prepared by reacting a terminal hydroxyl hyperbranched polyester with an aldehyde-modified polyacrylic acid; the aldehyde-modified polyacrylic acid is prepared by polymerizing acrylic acid with acrolein; and the polyamino polyether is prepared by reacting epichlorohydrin, dodecanol polyether and ammonia water.

4. The epoxy resin-based fireproof and heat-insulating coating according to claim 1, characterized in that: The film-forming agent is alcohol ester dodecanol; the curing agent is polyamide; and the defoaming agent is nonylphenol polyoxyethylene ether.

5. The method for preparing an epoxy resin-based fireproof and heat-insulating coating according to any one of claims 1 to 4, characterized in that: The specific steps include: S1. Under a nitrogen atmosphere, hydroxyl-hyperbranched polyethylene, dihydroxy-terminated polydioxanone, and tetrahydrofuran were mixed in a mass ratio of 0.6:(0.4-0.6):3, stirred uniformly, and then a 3-5% solution of dibutyltin dilaurate in tetrahydrofuran (0.08-0.1 times the mass of the hydroxyl-hyperbranched polyethylene) was added dropwise at a rate of 1-3 ml / min. The reaction was continued with stirring for 15-20 min, and triphenylisocyanate thiophosphate (0.4-0.6 times the mass of the hydroxyl-hyperbranched polyethylene) was added. The temperature was raised to 60-80°C, the reaction was carried out for 6-7 h, the reaction was quenched with glacial acetic acid, and the mixture was precipitated with methanol. The mixture was filtered and washed 3-5 times with methanol, and then dried in vacuo at 60-70°C to obtain a hyperbranched block copolymer. S2. The epoxy resin and the hyperbranched block copolymer were mixed in a mass ratio of 10:1~3, heated to 60~80°C, stirred at 400~600rpm for 30~40min, cooled to 48~52°C, and 6~7 times the mass of the epoxy resin as a curing agent, methyl hexahydrophthalic anhydride, was added, and the reaction was continued with stirring for 8~15min. Then, 0.01~0.03 times the mass of the epoxy resin as an accelerator, 2,4,6-tris(dimethylaminomethyl)phenol, was added, and the reaction was continued with stirring for 8~10min. The mixture was vacuum degassed, heated to 80~82°C, reacted for 2~3h, heated to 120~122°C, reacted for 2h, heated to 50~52°C, and reacted for 1~2h to obtain an epoxy resin base material. S3. The formaldehyde-modified polyacrylic acid, ethylene glycol, p-toluenesulfonic acid and dimethyl sulfoxide were mixed in a mass ratio of 2: (1-2): (0.02-0.03): (4-5), the temperature was raised to 58-62 ° C, the reaction was carried out for 2-3 hours, 1.1-1.2 times the mass of the formaldehyde-modified polyacrylic acid was added with a hydroxyl-terminated hyperbranched polyester and 0.001-0.002 times the mass of the formaldehyde-modified polyacrylic acid was added with a catalyst of 4-dimethylaminopyridine, the temperature was lowered to 48-52 ° C, and 1-3 ml / min was added. A dimethyl sulfoxide solution of 30-50% N,N'-dicyclohexylcarbodiimide (0.22-0.24 times the mass of the formaldehyded polyacrylic acid) was added dropwise at a rate of 1 / min, the temperature was raised to 78-82°C, the reaction was carried out for 8-9 hours, and 0.03-0.04% hydrochloric acid (1-1.2 times the mass of the formaldehyded polyacrylic acid) was added. The temperature was lowered to 38-42°C, the reaction was carried out for 3-4 hours, the mixture was dialyzed, and the mixture was freeze-dried at -40--60°C to prepare a polyaldehyde polyester. S4. Ammonium polyphosphate, ethanol and deionized water were mixed in a mass ratio of 1: (2-3): 1, ultrasonically treated at 40-60 kHz for 20-30 min, 0.2-0.3 times the mass of ammonium polyphosphate was added to a polyaldehyde polyester, the temperature was raised to 60-62 ° C, the reaction was carried out for 6-8 h, and then 0.1-0.2 times the mass of ammonium polyphosphate and 0.005-0.007 times the mass of ammonium polyphosphate were added to a catalyst of p-toluenesulfonic acid, the temperature was raised to 80-82 ° C, the reaction was carried out for 8-10 h, the mixture was cooled and centrifuged, washed with ethanol 3-5 times, and dried in vacuo at 60-70 ° C to obtain modified ammonium polyphosphate; S5. Mix modified ammonium polyphosphate and melamine by weight to prepare a flame retardant; mix the epoxy resin base material and the film-forming agent and add them to the reactor, stir at 600-800 rpm for 8-10 minutes, raise the temperature to 50-60°C, add the flame retardant, disperse at 1000-2000 rpm for 20-30 minutes, add expanded perlite and glass fiber, stir at 300-500 rpm for 10-13 minutes, add a defoaming agent and a curing agent, continue stirring for 5-8 minutes, and perform vacuum degassing to prepare an epoxy resin-based fire-retardant and heat-insulating coating.

6. The method for preparing an epoxy resin-based fireproof and heat-insulating coating according to claim 5, characterized in that: In step S1, the preparation method of hydroxy hyperbranched polyethylene is as follows: under a nitrogen atmosphere, ethylene, hydroxyethyl acrylate, catalyst di-(2,6-dimethylphenyl) hexamethylenediamine nickel bromide and toluene are mixed in a mass ratio of 1:(0.08~0.14):(0.002~0.004):(3~5), heated to 30~40°C, the pressure is 0.5~1.5MPa, reacted for 2~6h, and then added with 20~30 times the mass of ethylene and a mass fraction of 20~25% sodium hydroxide ethanol solution, continued to react for 30~50min, filtered and washed with methanol and deionized water 3~5 times in sequence, and vacuum dried at 60~80°C to obtain hydroxy hyperbranched polyethylene.

7. The method for preparing an epoxy resin-based fireproof and heat-insulating coating according to claim 5, characterized in that: In step S1, the preparation method of the double-terminal hydroxyl poly-p-dioxanone is as follows: under a nitrogen atmosphere, p-dioxanone and butanediol are mixed in a mass ratio of (20-40): (1-3), the temperature is raised to 80-110° C., and after stirring evenly, a 2-4% mass fraction of a catalyst stannous octoate toluene solution of 0.3-0.6 times the mass of p-dioxanone is added, the reaction is carried out for 48-72 hours, the mixture is cooled to room temperature, and the mixture is crushed to obtain the double-terminal hydroxyl poly-p-dioxanone.

8. The method for preparing an epoxy resin-based fireproof and heat-insulating coating according to claim 5, characterized in that: In the above step S3, the preparation method of the formaldehyde-modified polyacrylic acid is as follows: under a nitrogen atmosphere, acrylic acid and deionized water are mixed in a mass ratio of 1:1-2, stirred and dissolved, and then the pH is adjusted to 6.5-7.5 with 30% by mass of sodium hydroxide, 0.4-0.8 times the mass of acrylic acid of acrolein and 0.01-0.03 times the mass of acrylic acid of ammonium persulfate are added, the temperature is raised to 50-60°C, the reaction is carried out for 8-12 hours, the pH is adjusted to 2.0-2.2 with hydrochloric acid, and then precipitated with acetone. After dissolving in deionized water, the mixture is precipitated with acetone again, and finally dried in vacuo at 40-50°C to obtain the formaldehyde-modified polyacrylic acid.

9. The method for preparing an epoxy resin-based fireproof and heat-insulating coating according to claim 5, characterized in that: In step S4, the preparation method of polyamino polyether is as follows: under a nitrogen atmosphere, dodecanol polyether and DMC catalyst are mixed in a mass ratio of 10:0.1~0.2, heated to 115~120°C, and epichlorohydrin with a mass of 1~2 times the mass of dodecanol polyether is added dropwise at a rate of 1~3 ml / min, heated to 125~135°C, reacted for 5~6 hours, and after reduced pressure distillation, 2~3 times the mass of dodecanol polyether with a mass fraction of 25~28% ammonia water and 0.4~0.6 times the mass of dodecanol polyether with toluene, heated to 50~52°C, reacted for 3~4 hours, separated and washed with deionized water 3~5 times, and rotary evaporated to obtain polyamino polyether.

10. The use of an epoxy resin-based fireproof and heat-insulating coating according to claim 1, characterized in that: The epoxy resin-based fireproof and heat-insulating coating is used in the fields of petrochemical industry and construction.

Images