Synergistic flame retardant capable of playing roles under different combustion temperature gradients and homogeneous A2-level thermal insulation material

Abstract

The invention relates to the technical field of preparation of building thermal-insulation flame-retardant materials, in particular to a synergistic flame retardant and homogeneous A2-level thermal-insulation material which can play a role under different combustion temperature gradients, the synergistic flame retardant comprises a flame retardant A, a flame retardant B and a flame retardant C, and the mass ratio of the flame retardant A to the flame retardant B to the flame retardant C is (65-75): (25-30): (10-20); through the formula of the novel synergistic flame retardant, the flame retardant can play corresponding roles in different combustion temperature intervals, respectively volatilize at 300-500 DEG C in the early stage of combustion and 500-650 DEG C in the later stage of combustion to take away heat, and simultaneously form a glassy covering layer for combustibles, so that combustion is effectively inhibited, the problem of poor flame retardance of a traditional organic thermal insulation material is solved, and the flame retardant effect of the organic thermal insulation material is improved. The solid flame retardant is introduced while the excellent heat preservation performance of a traditional organic heat preservation material is reserved, the flame retardant effect is greatly improved, and the flame retardant grade is improved to the homogeneous A2 grade.

Description

Technical Field

[0001] The invention relates to the technical field of preparation of building thermal insulation and flame retardant materials, in particular to a synergistic flame retardant capable of exerting effects under different combustion temperature gradients and a homogeneous A2 grade thermal insulation material. Background Art

[0002] With the increasingly stringent fire safety regulations in buildings, Class A insulation materials are being used more and more widely. However, the annual improvement of national energy-saving standards has made it difficult for traditional Class A insulation materials such as rock wool and polystyrene boards to meet the increasingly stringent energy-saving standards, while the fire resistance of extruded boards and EPS boards is difficult to reach Class A. There is no product on the market with Class A flame retardant properties and good thermal insulation properties. How to improve the flame retardant properties of insulation materials with good thermal insulation effects to Class A is currently the main technical difficulty; the traditional method of improving the flame retardant properties of insulation materials is to change the matrix of the insulation materials by chemical methods, such as introducing a large number of stable functional group benzene rings, but this can only improve the insulation materials to Class B1, and it is difficult to improve them to Class A.

[0003] At present, most methods to improve the flame retardancy of thermal insulation materials are to increase the flame retardancy of thermal insulation materials to A2 level by adding a large amount of flame retardants. This is difficult to achieve on the one hand, and on the other hand it will affect other properties of the thermal insulation materials. For example, in the patent "Polyurethane Thermal Insulation Foam Material and Preparation Method thereof" CN107312149A, when aluminum hydroxide and magnesium hydroxide are used alone as flame retardants, a large amount is required to play a role, generally 40% to 60%, which seriously affects the mechanical properties of the material.

[0004] Therefore, the present invention proposes a synergistic flame retardant and a homogeneous A2 grade thermal insulation material that can function under different combustion temperature gradients. Summary of the invention

[0005] The present invention provides a synergistic flame retardant and a homogeneous A2-level thermal insulation material that can function under different combustion temperature gradients. The flame retardant can play different roles under different combustion temperature gradients to produce a synergistic effect, so that each flame retardant can play its function to the maximum extent, reducing the amount of a single flame retardant. After being added to traditional B-level thermal insulation materials such as polyurethane and phenolic resin, the flame retardant grade thereof can be increased to A2 level.

[0006] The technical solution of the present invention is as follows:

[0007] A synergistic flame retardant capable of functioning under different combustion temperature gradients. The synergistic flame retardant comprises flame retardant A, flame retardant B and flame retardant C. The mass ratio of flame retardants A, B and C is 65-75:25-30:10-20.

[0008] Furthermore, the synergistic flame retardant is produced by uniformly mixing flame retardant A, flame retardant B, and flame retardant C in a high-speed suspension mixer.

[0009] Furthermore, the flame retardant A is a heat-volatile flame retardant, which is composed of an early heat-volatile flame retardant A1 and a late heat-volatile flame retardant A2, which respectively work at 300-500°C in the early stage of combustion and 500°C-650°C in the late stage of combustion;

[0010] Further, the early heat volatilization type flame retardant A1 includes any one of boric acid, hexachlorocyclopentadiene, tetrabromobisphenol A, dicyandiamide, and cyanurate;

[0011] The late heat volatilization type flame retardant A2 includes any one of brominated polystyrene, brominated epoxy resin, brominated SBS, dibromomethane, trichlorobromomethane, dichlorobromomethane and octabromodiphenyl oxide.

[0012] Furthermore, the mass ratio of the early heat volatilization type flame retardant A1 to the late heat volatilization type flame retardant A2 is 80-100:9-10.

[0013] Furthermore, the flame retardant B is a coated flame retardant, including any one or a combination of two of phosphate, phosphite, aluminum phosphate, monobromodichloromethane, phosphorus-containing polyols, phosphorus-nitrogen compounds and organic hypophosphites.

[0014] Furthermore, the flame retardant C is a high-efficiency smoke suppression flame retardant, including any one of molybdenum trioxide, octamolybdate, calcium molybdate, calcium phosphomolybdate, zinc molybdate, and antimony trioxide.

[0015] A homogeneous A2-class thermal insulation material contains the synergistic flame retardant that can function under different combustion temperature gradients. The homogeneous A2-class thermal insulation material is formed by mixing and foaming a foaming material, a synergistic flame retardant and an inorganic filler. Based on the total weight of the thermal insulation material, the content of the foaming material is 20%-35%, the content of the synergistic flame retardant is 10%-15%, and the content of the inorganic filler is 50%-65%.

[0016] Furthermore, the inorganic filler is any one of silica aerogel, mine tailings, barite, ceramics, and slag, which is fully ground and has a particle size of 10 μm-950 μm.

[0017] Compared with the prior art, the present invention has the following beneficial effects:

[0018] 1. The present invention adopts a new synergistic flame retardant formula, which can work in different combustion temperature ranges (300-500°C in the early stage and 500-650°C in the later stage), which means that the flame retardant can not only respond quickly to the initial combustion stage, but also continue to work when the fire intensifies, providing continuous protection. The flame retardant volatilizes in two temperature ranges, can take away a large amount of heat, effectively reduce the temperature of the combustion area, thereby slowing down the combustion rate, and at the same time form a glass-like covering layer on the combustible material, effectively inhibiting combustion, overcoming the problem of poor flame retardancy of traditional organic thermal insulation materials. While retaining the excellent thermal insulation performance of traditional organic thermal insulation materials, by introducing solid flame retardants, the flame retardant effect is greatly improved, and its flame retardant grade is raised to homogeneous A2 level.

[0019] 2. The present invention overcomes the method of improving the flame retardant properties of thermal insulation materials by adding a large amount of single flame retardant, and utilizes the characteristics of various flame retardants for combination, and exerts the synergistic effect between different flame retardants. By exerting effects in various temperature ranges of 0-750°C (such as delaying the ignition time, suppressing the spread of fire, forming a protective layer, etc.), the combustion reaction is effectively suppressed, the flame retardant properties of the thermal insulation materials are significantly improved, and the amount of flame retardant used is effectively reduced. While ensuring that the flame retardant grade of the thermal insulation material reaches A2, the thermal conductivity and other properties of the thermal insulation material are guaranteed.

[0020] 3. The present invention can select solid waste such as slag through inorganic fillers, realize the recycling of waste, help solve the national solid waste treatment problem, reduce the accumulation and landfill of waste, reduce the pressure on the environment and benefit environmental protection. At the same time, the use of silica aerogel can further improve the thermal insulation performance of the thermal insulation material while ensuring the flame retardant level. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 The present invention is a flow chart for preparing the A2-class thermal insulation material containing a synergistic flame retardant. DETAILED DESCRIPTION

[0022] The following embodiments of the present invention are described in further detail in conjunction with the accompanying drawings and examples. The following examples are used to illustrate the present invention, but are not intended to limit the scope of the present invention.

[0023] like Figure 1 As shown, the present invention provides a synergistic flame retardant that can function under different combustion temperature gradients. The synergistic flame retardant includes flame retardant A, flame retardant B and flame retardant C. The mass ratio of flame retardants A, B and C is 65-75:25-30:10-20.

[0024] Furthermore, the synergistic flame retardant is produced by uniformly mixing flame retardant A, flame retardant B, and flame retardant C through a high-speed suspension mixer.

[0025] Furthermore, flame retardant A is a heat-volatile flame retardant, which is composed of an early heat-volatile flame retardant A1 and a late heat-volatile flame retardant A2, which respectively work at 300-500°C in the early stage of combustion and 500°C-650°C in the late stage of combustion;

[0026] Furthermore, the early heat-volatile flame retardant A1 includes any one of boric acid, hexachlorocyclopentadiene, tetrabromobisphenol A, dicyandiamide, and cyanurate;

[0027] The late heat volatilization type flame retardant A2 includes any one of brominated polystyrene, brominated epoxy resin, brominated SBS, dibromomethane, trichlorobromomethane, dichlorobromomethane and octabromodiphenyl oxide.

[0028] Furthermore, the mass ratio of the early heat volatilization type flame retardant A1 to the late heat volatilization type flame retardant A2 is 80-100:9-10.

[0029] Furthermore, the flame retardant B is a coated flame retardant, including any one or a combination of two of phosphate, phosphite, aluminum phosphate, monobromodichloromethane, phosphorus-containing polyols, phosphorus-nitrogen compounds and organic hypophosphites.

[0030] Furthermore, the flame retardant C is a high-efficiency smoke-suppressing flame retardant, including any one of molybdenum trioxide, octamolybdate, calcium molybdate, calcium phosphomolybdate, zinc molybdate, and antimony trioxide.

[0031] A homogeneous A2-class thermal insulation material contains a synergistic flame retardant that can function under different combustion temperature gradients. The homogeneous A2-class thermal insulation material is formed by mixing and foaming a foaming material, a synergistic flame retardant and an inorganic filler. Based on the total weight of the thermal insulation material, the content of the foaming material is 20%-35%, the content of the synergistic flame retardant is 10%-15%, and the content of the inorganic filler is 50%-65%. The foaming material is preferably polyurethane.

[0032] Furthermore, the inorganic filler is any one of silica aerogel, mine tailings, barite, ceramics, and slag, which is fully ground and has a particle size of 10 μm-950 μm.

[0033] Through the following specific implementation process, it is proved that synergistic flame retardants can play different roles under different combustion temperature gradients, produce synergistic effects, so that each flame retardant can maximize its function and reduce the amount of a single flame retardant.

[0034] Test process:

[0035] 1. Prepare a mixed solution of polyol, pentane blowing agent, catalyst and foam leveling agent in proportion, and stir the mixed solution for 30-60 minutes;

[0036] 2. Prepare isocyanate for foaming material;

[0037] 3. Put flame retardant A, flame retardant B, flame retardant C and inorganic filler into a V-type suspension mixer in proportion and mix at high speed;

[0038] 4. Drying the mixed flame retardant after high-speed suspension mixing to obtain a new synergistic flame retardant;

[0039] 5. Add a certain amount of the new synergistic flame retardant into the mixed solution, and stir it thoroughly with a stirrer to obtain a mixture A;

[0040] 6. Add a certain amount of the new synergistic flame retardant to the isocyanate and stir it thoroughly with a stirrer to obtain a mixture B.

[0041] 7. Pour mixed material A into mixed material B, and then stir it fully and quickly. After stirring, ripen and foam it to obtain the thermal insulation material.

[0042] Embodiment 1:

[0043] 1. Prepare a mixed solution by mixing 100 parts of polyether polyol, 12 parts of pentane blowing agent, 4 parts of catalyst and 4 parts of foam leveling agent. Stir the mixed solution for 30-60 minutes.

[0044] 2. Prepare 145 parts of isocyanate;

[0045] 3. 37 parts of cyanurate, 4 parts of bromochloromethane, 16 parts of aluminum phosphate, 7 parts of calcium phosphomolybdate and 190 parts of tailings are placed in a V-type suspension mixer in proportion for high-speed suspension mixing;

[0046] 4. Dry the mixed flame retardant after high-speed suspension mixing to obtain a new synergistic flame retardant. Through high-speed suspension mixing, the components in the mixture can be effectively uniformly distributed through physical contact, friction, movement and collision, thereby improving the compatibility of flame retardants A, B and C;

[0047] 5. Add a certain amount of the new synergistic flame retardant into the mixed solution, and stir it thoroughly with a stirrer to obtain a mixture A;

[0048] 6. Add a certain amount of the new synergistic flame retardant to the isocyanate and stir it thoroughly with a stirrer to obtain a mixture B;

[0049] 7. Pour mixed material A into mixed material B, and then stir it fully and quickly. After stirring, ripen and foam it to obtain the thermal insulation material.

[0050] Based on Example 1, the present invention further carries out Examples 2-6, wherein the experimental operations in Examples 2-6 and Comparative Examples 1-2 are the same as those in Example 1, and the modified parameters are specifically as follows:

[0051]

[0052]

[0053] It can be seen from the above embodiments and comparative examples that the present invention overcomes the problem of poor flame retardancy of traditional organic thermal insulation materials. While retaining the excellent thermal insulation performance of traditional organic thermal insulation materials, the flame retardant effect is greatly improved by introducing solid flame retardants, and the flame retardant grade thereof is increased to homogeneous A2 grade.

[0054] The synergistic flame retardant is based on a mixture of flame retardant A, flame retardant B, and flame retardant C, and can play corresponding roles in different combustion temperature ranges. In the early stage of combustion at 300-500°C, the solid sublimated gas in the flame retardant absorbs heat, takes away the heat, and decomposes to produce H2O and N2 non-combustible water vapor and gas, taking away the combustible gas and reducing the concentration of the combustible gas. In the later stage of combustion at 500-650°C, it evaporates and takes away the heat, and at the same time forms a glass-like covering layer on the combustible material, achieving no open flame and effectively suppressing combustion.

[0055] It overcomes the traditional method of improving the flame retardant properties of thermal insulation materials by adding a large amount of single flame retardant. It combines the characteristics of various flame retardants, exerts the synergistic effect between different flame retardants, and combines with inorganic fillers to work in the temperature range of 0-750℃, effectively reducing the amount of flame retardant used. While ensuring that the flame retardant grade of the thermal insulation material reaches A2, it also ensures the thermal conductivity and other properties of the thermal insulation material.

[0056] Among them, many organophosphorus flame retardants, especially phosphates, have poor heat resistance, high volatility, and unsatisfactory compatibility. At high temperatures, these flame retardants may decompose or migrate, affecting their flame retardant effects and material stability. The flame retardant B in the present invention effectively fixes the phosphate flame retardant by mixing with inorganic fillers, thereby ensuring its chemical stability and thermal stability.

[0057] At the same time, when the organophosphorus flame retardant is combined with the heat-volatile flame retardant (A1, A2), it is necessary to determine the optimal ratio and combination to improve their synergistic effect to achieve the best flame retardant effect. The present invention determines through experiments that the mass ratio of flame retardants A, B, and C is 65-75:25-30:10-20, and combines the vertical burning test and the peak heat release rate (PHRR) test to determine that the synergistic flame retardant of the present invention has a good flame retardant effect.

[0058] At the same time, inorganic fillers can be made of solid waste, which solves the domestic solid waste disposal problem and is beneficial to environmental protection. Inorganic fillers can be made of silica aerogel particles, which can further improve the thermal insulation effect of the thermal insulation material while ensuring the flame retardant level.

[0059] The embodiments of the present invention are provided for the purpose of illustration and description. Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limitations of the present invention. Ordinary technicians in this field can change, modify, replace and modify the above embodiments within the scope of the present invention.

Claims

1. A synergistic flame retardant capable of functioning under different combustion temperature gradients, characterized in that: The synergistic flame retardant includes flame retardant A, flame retardant B and flame retardant C, and the mass ratio of flame retardants A, B and C is 65-75:25-30:10-20.

2. A synergistic flame retardant capable of functioning under different combustion temperature gradients as claimed in claim 1, characterized in that: The synergistic flame retardant is produced by uniformly mixing flame retardant A, flame retardant B and flame retardant C through a high-speed suspension mixer.

3. A synergistic flame retardant capable of functioning under different combustion temperature gradients as claimed in claim 1, characterized in that: The flame retardant A is a heat-volatile flame retardant, which is composed of an early heat-volatile flame retardant A1 and a late heat-volatile flame retardant A2, and takes effect at 300-500°C in the early combustion stage and 500-650°C in the late combustion stage, respectively.

4. A synergistic flame retardant capable of functioning under different combustion temperature gradients as claimed in claim 3, characterized in that: The early heat volatilization type flame retardant A1 includes any one of boric acid, hexachlorocyclopentadiene, tetrabromobisphenol A, dicyandiamide, and cyanurate; The late heat volatilization type flame retardant A2 includes any one of brominated polystyrene, brominated epoxy resin, brominated SBS, dibromomethane, trichlorobromomethane, dichlorobromomethane and octabromodiphenyl oxide.

5. A synergistic flame retardant capable of functioning under different combustion temperature gradients as claimed in claim 4, characterized in that: The mass ratio of the early heat volatilization type flame retardant A1 to the late heat volatilization type flame retardant A2 is 80-100:9-10.

6. A synergistic flame retardant capable of functioning under different combustion temperature gradients as claimed in claim 1, characterized in that: The flame retardant B is a coated flame retardant, including any one or a combination of two of phosphate, phosphite, aluminum phosphate, monobromodichloromethane, phosphorus-containing polyols, phosphorus-nitrogen compounds and organic hypophosphites.

7. A synergistic flame retardant capable of functioning under different combustion temperature gradients as claimed in claim 1, characterized in that: The flame retardant C is a high-efficiency smoke-suppressing flame retardant, including any one of molybdenum trioxide, ammonium octamolybdate, calcium molybdate, calcium phosphomolybdate, zinc molybdate, and antimony trioxide.

8. A homogeneous A2 grade thermal insulation material, comprising the synergistic flame retardant capable of functioning under different combustion temperature gradients as claimed in any one of claims 1 to 7, characterized in that: The homogeneous A2 grade thermal insulation material is formed by mixing and foaming a foaming material, a synergistic flame retardant and an inorganic filler. Based on the total weight of the thermal insulation material, the foaming material content is 20%-35%, the synergistic flame retardant content is 10%-15%, and the inorganic filler content is 50%-65%.

9. A homogeneous A2 grade thermal insulation material as claimed in claim 8, characterized in that: The inorganic filler is any one of silica aerogel, mine tailings, barite, ceramics, and slag, which is fully ground and has a particle size of 10 μm-950 μm.

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