Environment-friendly solvent-free epoxy fireproof coating and preparation method thereof

Abstract

The invention discloses an environment-friendly solvent-free epoxy fireproof coating and a preparation method thereof, and belongs to the technical field of fireproof coatings, the environment-friendly solvent-free epoxy fireproof coating comprises a component A and a component B, the component A is prepared from the following raw materials in parts by weight: 30 to 40 parts of film-forming agent, 3 to 5 parts of reactive diluent, 30 to 70 parts of intumescent flame-retardant system, 12 to 16 parts of fireproof filler, 0.5 to 1.1 parts of anti-settling agent, 0.8 to 3 parts of modified inorganic nano filler and 0.2 to 0.6 part of defoaming agent; the component B comprises the following raw materials in parts by weight: 6-14 parts of a curing agent and 0.6-1.2 parts of a curing agent accelerator. The fireproof coating provided by the invention belongs to an environment-friendly coating, has excellent peel strength, fireproof performance, heat insulation performance and water resistance, is small in dosage, and greatly saves the application cost of the coating.

Description

Technical Field

[0001] The invention belongs to the technical field of fire retardant coatings, and in particular relates to an environmentally friendly solvent-free epoxy fire retardant coating and a preparation method thereof. Background Art

[0002] With the progress of the times, my country has attached more and more importance to the safety performance requirements in the fields of construction, industry and transportation. In the event of a fire, in order to reduce the spread of fire and ensure the safety of personnel and property, it is urgent to improve the fire resistance of building steel structures, industrial facilities and new energy vehicle batteries. Fire retardant coatings refer to a class of substances applied to the surface of the base layer, which can effectively reduce the flammability of the substrate, prevent the rapid spread of fire, and improve the fire resistance limit of the substrate. At present, the intumescent fire retardant coating of thermosetting epoxy resin is widely used. The functional groups such as epoxy, hydroxyl and ether bonds in epoxy resin give it good substrate wettability and excellent adhesion, but it also has disadvantages such as poor heat resistance, poor impact toughness and poor weather resistance.

[0003] In the disclosed formulas of epoxy fire retardant coatings, more attention is paid to solving the shortcomings of poor heat resistance and toughness of the coating by adding modified resins. Patent CN116925618A discloses an additive modified epoxy additive, which has a polyolefin main chain or an alkane branched structure and has an epoxy structural unit that can participate in the curing and cross-linking of the paint film, and can improve the expansion ratio of the carbon layer after burning, improve the uniform density of the pores of the expanded carbon layer, and improve the stability of the combination with the substrate, thereby achieving a heat insulation and protective effect. However, since the patented technology uses expanded graphite, the color of the coating is difficult to control and requires a thick coating of more than 1 mm. Patent CN116731300A discloses a linear polyester oligomer toughening agent with a flexible chain segment, which solves the defect of poor toughness of epoxy resin coatings, but the preparation method of the polyester oligomer toughening agent described in the invention is relatively complicated, which is not conducive to popularization and application. Patent CN11090378A discloses a solvent-free flexible epoxy fire retardant coating, but the coating needs to be applied thickly about 6mm to play a good fireproof and heat-insulating role; U.S. Patent US2023407108A discloses a microcapsule epoxy fire retardant coating with added fire extinguishing agent, which realizes automatic cooling and fire extinguishing by thermal decomposition and vaporization of the fire extinguishing agent microparticles, however, the application of microcapsule technology may bring challenges to the cost control of fire retardant coatings. Some of the disclosed epoxy fire retardant coatings use organic solvents or halogen-containing, sulfur-containing and other raw materials, which are not green and environmentally friendly coatings; water-based epoxy fire retardant coatings such as patent CN11344425A have the problem of slow coating curing speed and need to be heated for curing.

[0004] The unique properties of nanomaterials have opened up a new path for the development of the coating industry. It has been introduced in the current literature that by adding a small amount of nano oxides to the coating, the heat resistance and mechanical properties of the coating can be improved. Therefore, how to provide a method for preparing coatings using nanomaterials is a technical problem that those skilled in the art need to solve urgently. Summary of the invention

[0005] In order to solve the above technical problems, the present invention provides an environmentally friendly solvent-free epoxy fire retardant coating and a preparation method thereof.

[0006] To achieve the above object, the present invention provides the following technical solutions:

[0007] An environmentally friendly solvent-free epoxy fire retardant coating comprises component A and component B;

[0008] The component A comprises the following raw materials in parts by weight:

[0009] 30-40 parts of film former, 3-5 parts of active diluent, 30-70 parts of intumescent flame retardant system, 12-16 parts of fireproof filler, 0.5-1.1 parts of anti-settling agent, 0.8-3 parts of modified inorganic nanofiller and 0.2-0.6 parts of defoamer;

[0010] The component B comprises the following raw materials in parts by weight:

[0011] 6 to 14 parts of curing agent and 0.6 to 1.2 parts of curing agent accelerator.

[0012] Preferably, the mass ratio of component A to component B is (4-6):1.

[0013] Beneficial effects: The intumescent solvent-free epoxy fire-retardant coating provided by the present invention realizes the high-efficiency fireproof and heat-insulating effect of the coating through the synergistic effect of the intumescent flame retardant system, the inorganic fire-retardant filler and the modified inorganic nanofiller. The modified inorganic nanofiller used is a surface modification of the inorganic nanofiller by a modifier, which plays a bridging role. One end of the modifier is combined with the hydroxyl group on the surface of the inorganic nanofiller, which reduces the surface energy of the nanoparticles and reduces the agglomeration of the nanoparticles. The functional group at the other end can be better compatible with the matrix resin. The modified inorganic nanofiller is added to the matrix resin, which not only helps to improve the peeling strength of the coating, but also promotes the carbonization of the coating and improves the strength of the carbon layer.

[0014] Preferably, the intumescent flame retardant system is ammonium polyphosphate, melamine and dipentaerythritol.

[0015] More preferably, the mass ratio of the ammonium polyphosphate, melamine and dipentaerythritol is 2:1:1. The degree of polymerization of the ammonium polyphosphate is n>1000.

[0016] Beneficial effects: The present invention acts as an acid source, a gas source and a carbon source in the coating composition, and has excellent synergistic flame retardant effects in condensed phase and gas phase flame retardancy.

[0017] Preferably, the modified inorganic nanofiller is an inorganic nanooxide modified by a disilane coupling agent.

[0018] Preferably, the disilane coupling agent is a mixture of γ-glycidyloxypropyltrimethoxysilane and γ-(methacryloyloxy)propyltrimethoxysilane (mass ratio is 1:1);

[0019] and / or,

[0020] The inorganic nano-oxide is one or more selected from nano-titanium dioxide, nano-aluminum oxide, nano-zinc oxide, nano-iron oxide, and nano-magnesium oxide.

[0021] Beneficial effects: The modified inorganic nanofiller added into the coating can improve the mechanical properties of the coating, while promoting the formation of the carbonized layer and improving the strength of the carbonized layer.

[0022] Preferably, the film-forming agent is selected from bisphenol A epoxy resin E51 and / or bisphenol A epoxy resin E44.

[0023] Preferably, the active diluent is selected from phenyl glycidyl ether, C 12 -C 14 One of fatty glycidyl ether and hexanediol diglycidyl ether.

[0024] Beneficial effects: The above active diluent has a good dilution effect on bisphenol A resin and participates in the curing process.

[0025] Preferably, the defoamer is a silicone defoamer.

[0026] Beneficial effects: The above defoaming agent is suitable for oily systems, has strong anti-foaming ability, significant foam breaking effect, good thermal stability, and can withstand high temperatures for a long time.

[0027] Preferably, the anti-settling agent is fumed silica with a specific surface area of ​​200 m 2 / g.

[0028] Beneficial effects: Fumed silica can effectively prevent filler sedimentation and paint agglomeration, and improve storage stability.

[0029] Preferably, the fireproof filler is one or more selected from magnesium hydroxide, aluminum hydroxide, calcium carbonate, calcium silicate, and glass fiber.

[0030] Beneficial effects: The above fireproof fillers are low in cost and can be used as flame retardants for coatings. They also have low thermal conductivity and can improve the strength of the carbonized layer.

[0031] Preferably, the curing agent is a polyamide curing agent with a viscosity range of 80 to 120 mPa.s and an amine value range of 600 to 700 mg KOH / g; and / or,

[0032] The curing agent accelerator is 2,4,6-tris(dimethylaminomethyl)phenol.

[0033] Beneficial effects: Polyamide curing agent is a fast curing agent for epoxy resin at room temperature. Its flexible structure can improve the toughness of the cured coating, and the synergistic curing agent accelerator can adjust the curing time.

[0034] A method for preparing an environmentally friendly solvent-free epoxy fire retardant coating comprises the following steps:

[0035] The anti-settling agent, the intumescent flame retardant system and the fireproof filler are ground, and then fully mixed and dispersed with the film-forming agent, the active diluent, the defoaming agent and the modified inorganic nanofiller to obtain component A;

[0036] The curing agent and the curing agent accelerator are fully mixed to obtain component B;

[0037] The component A and the component B are mixed evenly to obtain the environmentally friendly solvent-free epoxy fire retardant coating.

[0038] Preferably, the grinding is grinding to a particle size of less than 100 μm.

[0039] Compared with the prior art, the present invention has the following advantages and technical effects:

[0040] The fire-retardant coating provided by the present invention does not contain organic solvents, halogens and sulfur elements, is an environmentally friendly coating, has excellent peel strength, fire resistance, heat insulation and water resistance, and has excellent fire resistance and heat insulation properties when the coating thickness reaches 0.2-0.3 mm, and has a small amount of use, which greatly saves the application cost of the coating. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] The drawings constituting a part of the present application are used to provide a further understanding of the present application. The illustrative embodiments and descriptions of the present application are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0042] Figure 1 This is the morphology of the coating after burning in Example 1;

[0043] Figure 2 This is the morphology of the coating after burning in Example 2;

[0044] Figure 3 This is the morphology of the coating after burning in Example 3;

[0045] Figure 4 This is the morphology of the coating after burning in Example 4;

[0046] Figure 5 This is the morphology of the coating after burning in Example 5;

[0047] Figure 6 The back surface temperature rise curve of the coating of Example 1-5 within 5 minutes;

[0048] Figure 7 This is a diagram of a vertical combustion device for a coating according to an embodiment of the present invention. DETAILED DESCRIPTION

[0049] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only 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.

[0050] The embodiment of the present invention discloses a solvent-free epoxy fire-retardant coating, which uses bisphenol A epoxy resin as a coating film-forming agent and polyamide as a curing agent, and realizes efficient fireproofing and heat insulation of the coating through the synergistic effect of an intumescent flame retardant system, an inorganic fireproof filler and a modified inorganic nanofiller. The use of modified inorganic nanofillers not only helps to improve the peeling strength of the coating, but also promotes the carbonization of the coating and improves the strength of the carbon layer.

[0051] The intumescent solvent-free epoxy fire retardant coating of the present invention has the following technical features:

[0052] (1) The fire retardant coating does not contain organic solvents, halogens and sulfur elements and is an environmentally friendly coating.

[0053] (2) The fire retardant coating has excellent peel strength, fire retardancy, heat insulation and water resistance.

[0054] (3) The ultra-thin coating (0.2-0.3 mm) of the fire retardant coating has excellent fire retardant and heat insulation properties.

[0055] The embodiment of the present invention discloses an environmentally friendly solvent-free epoxy fire retardant coating which is a two-component fire retardant coating, consisting of component A and component B, and the formula composition is as follows (by weight):

[0056] Component A

[0057] 30-40 parts of film former, 3-5 parts of active diluent, 30-70 parts of intumescent flame retardant system, 12-16 parts of fireproof filler, 0.5-1.1 parts of anti-settling agent, 0.8-3 parts of modified inorganic nanofiller and 0.2-0.6 parts of defoamer;

[0058] Component B

[0059] 6-14 parts of polyamide curing agent and 0.6-1.2 parts of curing agent accelerator;

[0060] The preparation method of an environmentally friendly solvent-free epoxy fire retardant coating described in the present invention is as follows:

[0061] (1) First, an anti-settling agent, an intumescent flame retardant system, and a fireproof filler are ground into a powder with a particle size of less than 100 μm in a ball mill, and then fully mixed and dispersed with a film-forming agent, an active diluent, a defoaming agent, and a modified inorganic nanofiller at room temperature to obtain component A.

[0062] (2) The curing agent and the curing agent accelerator are thoroughly mixed at room temperature to obtain component B.

[0063] (3) Before painting, mix component A and component B in the ratio of (3-6): 1 and apply within 1 hour.

[0064] In some embodiments of the present invention, the modified inorganic nanofiller is an inorganic nanooxide modified by a mixture of a disilane coupling agent γ-glycidyloxypropyltrimethoxysilane and γ-(methacryloyloxy)propyltrimethoxysilane (mass ratio 1:1).

[0065] In some embodiments of the present invention, the inorganic nano-oxide is one or more of nano-titanium dioxide, nano-aluminum oxide, nano-zinc oxide, nano-iron oxide, and nano-magnesium oxide, and the particle size thereof is 10-100 nm.

[0066] In some embodiments of the present invention, the preparation method of the modified inorganic nanofiller is: weigh 2g of inorganic nano oxide, add it to 100mL of 37.5% ethanol solution, ultrasonically disperse the mixture for 30min, then add 0.06g of a mixed solution of γ-glycidyloxypropyltrimethoxysilane and γ-(methacryloyloxy)propyltrimethoxysilane in a mass ratio of 1:1, heat it to 60°C, stir and react for 2h, cool it, centrifuge and dry the product to obtain a modified inorganic nanofiller.

[0067] In some embodiments of the present invention, the film-forming agent is bisphenol A epoxy resin E51, E44 or a mixture thereof.

[0068] In some embodiments of the present invention, the active diluent is one of phenyl glycidyl ether, C12-C14 fatty glycidyl ether, and hexanediol diglycidyl ether.

[0069] In some embodiments of the present invention, the defoaming agent is a silicone defoaming agent.

[0070] In some embodiments of the present invention, the anti-settling agent is fumed silica with a specific surface area of ​​200 m 2 / g.

[0071] In some embodiments of the present invention, the intumescent flame retardant system is ammonium polyphosphate-melamine-dipentaerythritol, and the mass ratio thereof is 2:1:1. The degree of polymerization of the ammonium polyphosphate is n>1000.

[0072] In some embodiments of the present invention, the fireproof filler is one or more of magnesium hydroxide, aluminum hydroxide, calcium carbonate, calcium silicate, and glass fiber.

[0073] In some embodiments of the present invention, the curing agent is a polyamide curing agent with a viscosity ranging from 80 to 120 mPa.s and an amine value ranging from 600 to 700 mg KOH / g.

[0074] In some embodiments of the present invention, the curing agent accelerator is 2,4,6-tris(dimethylaminomethyl)phenol.

[0075] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0076] Unless otherwise specified, room temperature or normal temperature in the present invention refers to 25±3°C.

[0077] Unless otherwise specified, the raw materials in the examples of the present invention were purchased from commercial sources.

[0078] Embodiment 1:

[0079] A method for preparing an environmentally friendly solvent-free epoxy fire retardant coating comprises the following steps:

[0080] (1) Preparation of modified nano-titanium dioxide

[0081] (1-1) Weighing 2 g of inorganic nano-titanium dioxide with a particle size of 20 nm, adding it to 100 mL of ethanol solution with a volume concentration of 37.5%, and ultrasonically dispersing it for 30 minutes to obtain a dispersion;

[0082] (1-2) mixing γ-glycidyloxypropyltrimethoxysilane and γ-(methacryloyloxy)propyltrimethoxysilane in a mass ratio of 1:1 to obtain a silane coupling agent mixed solution;

[0083] (1-3) The above dispersion was poured into a three-necked flask equipped with a condenser and a mechanical stirring device, and 0.06 g of the above silane coupling agent mixture was added dropwise at a speed of 1000 rpm. After the addition was completed, the temperature was raised to 60° C. to react for 2 h. After the reaction was completed, the mixture was cooled to room temperature, and the product was centrifuged and dried to obtain the final product, modified nano-titanium dioxide.

[0084] (2) 20 g of epoxy resin E51, 10 g of epoxy resin E44, 3 g of phenyl glycidyl ether, 0.4 g of silicone defoamer and 0.8 g of modified nano titanium dioxide obtained in step (1) were put into a disperser and dispersed at a speed of 500 rpm for 30 min. Then 0.8 g of fumed silica, 15 g of ammonium polyphosphate, 7.5 g of melamine, 7.5 g of dipentaerythritol, 8 g of light calcium carbonate with a particle size of 5 μm and 4 g of calcium silicate with a particle size of 40 μm were ground in a ball mill for 1 h and then put into a disperser and dispersed at a speed of 1000 rpm for 3 hours, and the material was discharged to obtain component A.

[0085] (3) 10 g of low-viscosity polyamide curing agent 593 and 0.9 g of 2,4,6-tris(dimethylaminomethyl)phenol were added to a disperser, dispersed at a speed of 500 rpm for 5 min, and discharged to obtain component B.

[0086] (4) Component A and component B are mixed evenly in a mass ratio of 5:1 to obtain a fire retardant coating, which is then sprayed or brushed onto the surface of the substrate.

[0087] Example 2

[0088] A method for preparing an environmentally friendly solvent-free epoxy fire retardant coating comprises the following steps:

[0089] (1) Preparation of modified nano-alumina

[0090] (1-1) Weigh 2 g of nano-alumina with a particle size of 30 nm, add it to 100 mL of ethanol solution with a volume concentration of 37.5%, and disperse it by ultrasonic for 30 minutes to obtain a dispersion;

[0091] (1-2) mixing γ-glycidyloxypropyltrimethoxysilane and γ-(methacryloyloxy)propyltrimethoxysilane in a mass ratio of 1:1 to obtain a silane coupling agent mixed solution;

[0092] (1-3) Pour the above dispersion into a three-necked flask equipped with a condenser and a mechanical stirring device, and drop 0.06g of the above silane coupling agent mixed solution at a speed of 1000rpm. After the dropwise addition is completed, the temperature is raised to 60°C for reaction for 2h. After the reaction is completed, cool to room temperature, centrifuge and dry the product to obtain the final product, modified nano-alumina.

[0093] (2) 25 g of epoxy resin E51, 5 g of epoxy resin E44, 5 g of C12-C14 fatty glycidyl ether, 0.4 g of silicone defoamer and 1.6 g of modified nano-alumina obtained in step (1) were put into a disperser and dispersed at a speed of 500 rpm for 30 min. Then 0.8 g of fumed silica, 30 g of ammonium polyphosphate, 15 g of melamine, 15 g of dipentaerythritol, 8 g of magnesium hydroxide with a particle size of 1.5 μm and 4 g of glass fiber with a particle size of 50 μm were ground in a ball mill for 1 h and then put into a disperser and dispersed at a speed of 1000 rpm for 3 hours, and the material was discharged to obtain component A.

[0094] (3) 10 g of low-viscosity polyamide curing agent 593 and 0.9 g of 2,4,6-tris(dimethylaminomethyl)phenol were added to a disperser, dispersed at a speed of 500 rpm for 5 min, and discharged to obtain component B.

[0095] (4) Component A and component B are mixed evenly in a mass ratio of 4:1 to obtain a fire retardant coating, which is then sprayed or brushed onto the surface of the substrate.

[0096] Example 3

[0097] A method for preparing an environmentally friendly solvent-free epoxy fire retardant coating comprises the following steps:

[0098] (1) Preparation of modified nano zinc oxide

[0099] (1-1) Weigh 2 g of nano zinc oxide with a particle size of 80 nm, add it to 100 mL of ethanol solution with a volume concentration of 37.5%, and disperse it by ultrasonic for 30 minutes to obtain a dispersion;

[0100] (1-2) mixing γ-glycidyloxypropyltrimethoxysilane and γ-(methacryloyloxy)propyltrimethoxysilane in a mass ratio of 1:1 to obtain a silane coupling agent mixed solution;

[0101] (1-3) The above dispersion was poured into a three-necked flask equipped with a condenser and a mechanical stirring device, and 0.06 g of the above silane coupling agent mixture was added dropwise at a speed of 1000 rpm. After the addition was completed, the temperature was raised to 60° C. and reacted for 2 h. After the reaction was completed, the mixture was cooled to room temperature, and the product was centrifuged and dried to obtain the final product, modified nano zinc oxide.

[0102] (2) 30g of epoxy resin E51, 5g of C12-C14 fatty glycidyl ether, 0.4g of organosilicon defoamer and 2g of modified nano zinc oxide obtained in step (1) were put into a disperser and dispersed at a speed of 500rpm for 30min. Then 0.8g of fumed silica, 24g of ammonium polyphosphate, 12g of melamine, 12g of dipentaerythritol, 6g of magnesium hydroxide with a particle size of 1.5μm, 2g of calcium carbonate with a particle size of 5μm and 4g of glass fiber with a particle size of 50μm were ground in a ball mill for 1h and then put into a disperser and dispersed at a speed of 1000rpm for 3 hours, and discharged to obtain component A.

[0103] (3) 10 g of low-viscosity polyamide curing agent 593 and 0.9 g of 2,4,6-tris(dimethylaminomethyl)phenol were added to a disperser, dispersed at a speed of 500 rpm for 5 min, and discharged to obtain component B.

[0104] (4) Component A and component B are mixed evenly in a mass ratio of 6:1 to obtain a fire retardant coating, which is then sprayed or brushed on the surface of the substrate.

[0105] Example 4

[0106] A method for preparing an environmentally friendly solvent-free epoxy fire retardant coating comprises the following steps:

[0107] (1) Preparation of modified nano copper oxide

[0108] (1-1) Weigh 2 g of nano copper oxide with a particle size of 50 nm, add it to 100 mL of 37.5% ethanol solution, and ultrasonically disperse it for 30 minutes to obtain a dispersion;

[0109] (1-2) mixing γ-glycidyloxypropyltrimethoxysilane and γ-(methacryloyloxy)propyltrimethoxysilane in a mass ratio of 1:1 to obtain a silane coupling agent mixed solution;

[0110] (1-3) The above dispersion was poured into a three-necked flask equipped with a condenser and a mechanical stirring device, and 0.06 g of the above silane coupling agent mixture was added dropwise at a speed of 1000 rpm. After the addition was completed, the temperature was raised to 60° C. to react for 2 h. After the reaction was completed, the mixture was cooled to room temperature, and the product was centrifuged and dried to obtain the final product, modified nano copper oxide.

[0111] (2) 20 g of epoxy resin E51, 15 g of epoxy resin E44, 5 g of hexanediol diglycidyl ether, 0.4 g of silicone defoamer and 2.4 g of modified nano copper oxide were put into a disperser and dispersed at a speed of 500 rpm for 30 min. Then 0.8 g of fumed silica, 30 g of ammonium polyphosphate, 15 g of melamine, 15 g of dipentaerythritol, 8 g of aluminum hydroxide with a particle size of 1.5 μm and 4 g of magnesium hydroxide with a particle size of 1.5 μm were ground in a ball mill for 1 h and then put into a disperser and dispersed at a speed of 1000 rpm for 3 hours, and the material was discharged to obtain component A.

[0112] (3) 10 g of low-viscosity polyamide curing agent 593 and 0.9 g of 2,4,6-tris(dimethylaminomethyl)phenol were added to a disperser, dispersed at a speed of 500 rpm for 5 min, and discharged to obtain component B.

[0113] (4) Component A and component B are mixed evenly in a mass ratio of 5:1 to obtain a fire retardant coating, which is then sprayed or brushed onto the surface of the substrate.

[0114] Example 5

[0115] A method for preparing an environmentally friendly solvent-free epoxy fire retardant coating comprises the following steps:

[0116] (1) Preparation of modified nano iron oxide

[0117] (1-1) Weighing 2 g of nano-iron oxide with a particle size of 100 nm, adding it to 100 mL of ethanol solution with a volume concentration of 37.5%, and ultrasonically dispersing it for 30 minutes to obtain a dispersion;

[0118] (1-2) mixing γ-glycidyloxypropyltrimethoxysilane and γ-(methacryloyloxy)propyltrimethoxysilane in a mass ratio of 1:1 to obtain a silane coupling agent mixed solution;

[0119] (1-3) The above dispersion was poured into a three-necked flask equipped with a condenser and a mechanical stirring device, and 0.06 g of the above silane coupling agent mixture was added dropwise at a speed of 1000 rpm. After the addition was completed, the temperature was raised to 60° C. to react for 2 h. After the reaction was completed, the mixture was cooled to room temperature, and the product was centrifuged and dried to obtain the final product, modified nano iron oxide.

[0120] (2) 30 g of epoxy resin E51, 5 g of epoxy resin E44, 5 g of C12-C14 fatty glycidyl ether, 0.4 g of silicone defoamer and 3 g of modified nano iron oxide were put into a disperser and dispersed at a speed of 500 rpm for 30 min. Then 0.8 g of fumed silica, 20 g of ammonium polyphosphate, 10 g of melamine, 10 g of dipentaerythritol, 6 g of light calcium carbonate with a particle size of 5 μm, 2 g of calcium silicate with a particle size of 40 μm, and 4 g of glass fiber with a particle size of 50 μm were ground in a ball mill for 1 h and then put into a disperser and dispersed at a speed of 1000 rpm for 3 hours, and discharged to obtain component A.

[0121] (3) 10 g of low-viscosity polyamide curing agent 593 and 0.9 g of 2,4,6-tris(dimethylaminomethyl)phenol were added to a disperser, dispersed at a speed of 500 rpm for 5 min, and discharged to obtain component B.

[0122] (4) Component A and component B are mixed evenly in a mass ratio of 4:1 to obtain a fire retardant coating, which is then sprayed or brushed onto the surface of the substrate.

[0123] Comparative Example 1

[0124] A method for preparing an environmentally friendly solvent-free epoxy fire retardant coating is different from Example 1 in that step (1) is not included, and the modified nano titanium dioxide in step (2) is replaced by nano titanium dioxide of equal mass. Other process steps and parameters are the same as those in Example 1.

[0125] Comparative Example 2

[0126] A method for preparing an environmentally friendly solvent-free epoxy fire retardant coating is different from Example 1 in that step (1) is not included, and modified nano titanium dioxide is not included in step (2). Other process steps and parameters are the same as those in Example 1.

[0127] Comparative Example 3

[0128] A method for preparing an environmentally friendly solvent-free epoxy fire retardant coating is different from that of Example 1 in that: step (2) does not include an intumescent flame retardant system, that is, does not include ammonium polyphosphate, melamine and dipentaerythritol. Other process steps and parameters are the same as those of Example 1.

[0129] Comparative Example 4

[0130] A method for preparing an environmentally friendly solvent-free epoxy fire retardant coating is different from that of Example 1 in that the intumescent flame retardant system in step (2) does not include a fire retardant filler. Other process steps and parameters are the same as those of Example 1.

[0131] Technical effects:

[0132] 1. The performance of the environmentally friendly solvent-free epoxy fire retardant coatings prepared in Examples 1 to 5 was tested according to the national standard GB14907-2018 "Steel Structure Fire Retardant Coatings", and the relevant test results are shown in Table 1 below:

[0133] Table 1

[0134]

[0135]

[0136] The performance of the environmentally friendly solvent-free epoxy fire retardant coatings prepared in Comparative Examples 1 to 4 of this embodiment was tested according to the national standard GB14907-2018 "Steel Structure Fire Retardant Coatings", and the relevant test results are shown in Table 2 below:

[0137] Table 2

[0138]

[0139]

[0140] It can be seen from Tables 1 and 2 that the fire retardant coatings obtained in Examples 1-5 of the present invention meet the GB14907-2018 standard, have good acid resistance, alkali resistance, water resistance and resistance to cold and hot cycles, and after the coating reaches 0.2-0.3 mm, the fire resistance limit can reach 1.2-1.6h, which has good fire resistance.

[0141] 2. Use a homemade vertical combustion device (such as Figure 7 The fireproof and heat-insulating properties of the coatings obtained in Examples 1-5 were tested, and the results are as follows: Figure 1-5 As shown in Figure 2, all samples were completely carbonized and expanded within about 1 minute of burning, forming an expanded carbonized layer more than 100 times, and the temperature on the back of the substrate stabilized at 250±10℃ after 90 seconds (as shown in Figure 2). Figure 6 ).

[0142] The above are only preferred specific implementations of the present application, but the protection scope of the present application is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed in the present application should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

Claims

1. An environmentally friendly solvent-free epoxy fire retardant coating, characterized in that: Comprising component A and component B in a mass ratio of (4-6):1; Wherein, the component A comprises the following raw materials in parts by weight: 30-40 parts of film former, 3-5 parts of active diluent, 30-70 parts of intumescent flame retardant system, 12-16 parts of fireproof filler, 0.5-1.1 parts of anti-settling agent, 0.8-3 parts of modified inorganic nanofiller and 0.2-0.6 parts of defoamer; The component B comprises the following raw materials in parts by weight: 6 to 14 parts of curing agent and 0.6 to 1.2 parts of curing agent accelerator.

2. An environmentally friendly solvent-free epoxy fire retardant coating according to claim 1, characterized in that: The intumescent flame retardant system comprises ammonium polyphosphate, melamine and dipentaerythritol.

3. The environmentally friendly solvent-free epoxy fire retardant coating according to claim 1, characterized in that: The modified inorganic nano filler is an inorganic nano oxide modified by a disilane coupling agent.

4. The environmentally friendly solvent-free epoxy fire retardant coating according to claim 3, characterized in that: The disilane coupling agent is a mixture of γ-glycidyloxypropyltrimethoxysilane and γ-(methacryloxy)propyltrimethoxysilane; and / or, The inorganic nano-oxide is selected from one or more of nano-titanium dioxide, nano-aluminum oxide, nano-zinc oxide, nano-iron oxide, and nano-magnesium oxide.

5. The environmentally friendly solvent-free epoxy fire retardant coating according to claim 1, characterized in that: The active diluent is selected from phenyl glycidyl ether, C 12 -C 14 One of fatty glycidyl ether and hexanediol diglycidyl ether.

6. The environmentally friendly solvent-free epoxy fire retardant coating according to claim 1, characterized in that: The anti-settling agent is fumed silica with a specific surface area of ​​200m 2 / g.

7. The environmentally friendly solvent-free epoxy fire retardant coating according to claim 1, characterized in that: The curing agent is a polyamide curing agent; and / or, The curing agent accelerator is selected from 2,4,6-tris(dimethylaminomethyl)phenol.

8. A method for preparing an environmentally friendly solvent-free epoxy fire retardant coating as claimed in any one of claims 1 to 7, characterized in that: The following steps are involved: The anti-settling agent, the intumescent flame retardant system and the fireproof filler are ground, and then fully mixed and dispersed with the film-forming agent, the active diluent, the defoaming agent and the modified inorganic nanofiller to obtain component A; The curing agent and the curing agent accelerator are fully mixed to obtain component B; The component A and the component B are mixed evenly to obtain the environmentally friendly solvent-free epoxy fire retardant coating.

9. The method for preparing an environmentally friendly solvent-free epoxy fire retardant coating according to claim 8, characterized in that: The grinding is grinding to a particle size of less than 100 μm.

10. An environmentally friendly solvent-free epoxy fire retardant coating, characterized in that: The coating is prepared from the coating according to any one of claims 1 to 7.

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