Flame-retardant sealant and preparation method thereof

Abstract

The invention provides a flame-retardant sealant and a preparation method thereof. The flame-retardant sealant comprises the following components in parts by weight: a silane modified polyether polymer, a plasticizer, a filler, fumed silica, a thixotropic agent, a moisture scavenger, a silane coupling agent and a curing agent, the plasticizer is selected from any one or a combination of at least two of diisodecyl phthalate, diisononyl phthalate, a polyether plasticizer and alkyl benzene sulfonate, and the filler comprises modified aluminum hydroxide. According to the flame-retardant sealant and the preparation method thereof, the specific components of the flame-retardant sealant are designed, and the flame-retardant sealant which has better flame retardance and better mechanical property, is relatively low in manufacturing cost and is more beneficial to large-scale commercial production can be prepared through the matching effect of all the components on the premise that a phosphorus flame retardant is not used.

Description

Technical Field

[0001] This invention belongs to the field of sealant materials technology, specifically relating to a flame-retardant sealant and its preparation method, and more specifically to a silane-modified polyether flame-retardant sealant and its preparation method. Background Technology

[0002] Flame-retardant one-component or two-component sealants are gaining increasing attention in the market. These sealants typically contain inorganic or organic phosphorus-based flame retardants. To enhance flame-retardant efficiency, the amount of flame retardant added is generally large. However, this increased amount leads to a significant decrease in the mechanical properties of the sealant. Furthermore, phosphorus-based flame retardants suffer from compatibility issues, high volatility, and dripping during combustion. Flame-retardant fillers are usually used in combination with flame retardants. To achieve a V0 flame retardant rating, the content of fillers is generally high, resulting in a significant decrease in the tensile strength, elongation at break, shear strength, and adhesive properties of the sealant. The sealant also becomes brittle, easily breaking under relatively small forces. The use of phosphorus-based flame-retardant plasticizers and flame-retardant powders further increases the manufacturing cost of the sealant, hindering large-scale commercial production.

[0003] Therefore, how to prepare flame-retardant sealants with good flame retardancy, good mechanical properties, and relatively low manufacturing cost, which are more conducive to large-scale commercial production, without using phosphorus-based flame retardants, has become an urgent technical problem to be solved. Summary of the Invention

[0004] To address the shortcomings of existing technologies, the present invention aims to provide a flame-retardant sealant and its preparation method, more specifically relating to a silane-modified polyether-based flame-retardant sealant and its preparation method. By designing the specific composition of the flame-retardant sealant and through the synergistic effect of its components, the present invention achieves a flame-retardant sealant with both good flame retardancy and good mechanical properties, while also having relatively low manufacturing costs, making it more suitable for large-scale commercial production, without the use of phosphorus-based flame retardants.

[0005] To achieve this objective, the present invention adopts the following technical solution:

[0006] In a first aspect, the present invention provides a flame-retardant sealant comprising the following components in parts by weight: 250-300 parts of silane-modified polyether polymer, 90-120 parts of plasticizer, 550-650 parts of filler, 20-50 parts of fumed silica, 10-15 parts of thixotropic agent, 10-30 parts of dehydrating agent, 5-20 parts of silane coupling agent, and 1.5-5 parts of curing agent; wherein the plasticizer is selected from any one or a combination of at least two of diisodecyl phthalate (DIDP), diisononyl phthalate (DINP), polyether plasticizers, and alkylbenzene sulfonates; and the filler comprises modified aluminum hydroxide.

[0007] This invention designs the specific composition of the flame-retardant sealant and, through the synergistic effect of each component, can prepare a flame-retardant sealant with good flame retardancy and mechanical properties without the use of phosphorus-based flame retardants. At the same time, the manufacturing cost is relatively low, which is more conducive to large-scale commercial production.

[0008] Furthermore, this invention uses modified aluminum hydroxide as a flame retardant, combined with a specific plasticizer, and then blends it with other components. Through the synergistic effect of each component, a flame-retardant sealant with excellent comprehensive performance is prepared.

[0009] Meanwhile, by controlling the amount of plasticizer in the flame-retardant sealant within a specific range, this invention has prepared a flame-retardant sealant that combines good flame retardancy and good mechanical properties. If the amount of plasticizer is too small, the flame-retardant sealant will have poor toughness and low elongation at break after curing; if the amount of plasticizer is too large, oil seepage will occur, the tensile strength of the flame-retardant sealant will decrease after curing, and the flame-retardant performance will also be reduced.

[0010] In this invention, the weight percentage of the silane-modified polyether polymer in the flame-retardant sealant can be 250 parts, 255 parts, 260 parts, 265 parts, 270 parts, 275 parts, 280 parts, 285 parts, 290 parts, 295 parts, or 300 parts, etc.

[0011] The plasticizer in the flame-retardant sealant can be in the following weight proportions: 90 parts, 93 parts, 96 parts, 99 parts, 102 parts, 105 parts, 108 parts, 111 parts, 114 parts, 117 parts, or 120 parts, etc.

[0012] The filler in the flame-retardant sealant can be in the following weight proportions: 550 parts, 560 parts, 570 parts, 580 parts, 590 parts, 600 parts, 610 parts, 620 parts, 630 parts, 640 parts, or 650 parts, etc.

[0013] The weight percentage of fumed silica in the flame-retardant sealant can be 20 parts, 23 parts, 26 parts, 29 parts, 32 parts, 35 parts, 38 parts, 41 parts, 44 parts, 47 parts, or 50 parts, etc.

[0014] The thixotropic agent in the flame-retardant sealant can be in the following weight proportions: 10 parts, 10.5 parts, 11 parts, 11.5 parts, 12 parts, 12.5 parts, 13 parts, 13.5 parts, 14 parts, 14.5 parts, or 15 parts, etc.

[0015] The weight percentage of the dehydrating agent in the flame-retardant sealant can be 10, 12, 14, 16, 18, 20, 22, 24, 26, 28, or 30 parts, etc.

[0016] The weight percentage of the silane coupling agent in the flame-retardant sealant can be 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, or 20 parts, etc.

[0017] The weight percentage of the curing agent in the flame-retardant sealant can be 1.5 parts, 2 parts, 2.5 parts, 3 parts, 3.5 parts, 4 parts, 4.5 parts, or 5 parts, etc.

[0018] The following are preferred technical solutions of the present invention, but are not intended to limit the technical solutions provided by the present invention. The purpose and beneficial effects of the present invention can be better achieved and realized through the following preferred technical solutions.

[0019] Preferably, the polyether plasticizer is selected from polyether C2020 and / or polyether 2000.

[0020] In this invention, polyether C2020 was purchased from Wanhua; polyether 2000 was purchased from Lanxing Dongda, with the grade DL-2000D.

[0021] Preferably, the plasticizer is a polyether plasticizer.

[0022] The present invention further optimizes the use of polyether plasticizers, thereby further improving the overall performance of the flame-retardant sealant.

[0023] Preferably, the D50 particle size of the modified aluminum hydroxide is 3 μm - 10 μm, for example, it can be 3 μm, 3.5 μm, 4 μm, 4.5 μm, 5 μm, 5.5 μm, 6 μm, 6.5 μm, 7 μm, 7.5 μm, 8 μm, 8.5 μm, 9 μm, 9.5 μm or 10 μm, etc.

[0024] Preferably, the whiteness of the modified aluminum hydroxide is 99.5% ± 0.5%, for example, it can be 99.0%, 99.1%, 99.2%, 99.3%, 99.4%, 99.5%, 99.6%, 99.7%, 99.8%, 99.9%, or 100%, etc.

[0025] Preferably, the modified aluminum hydroxide has an oil absorption value of 30 g / 100g - 35 g / 100g, for example, it can be 30 g / 100g, 30.5 g / 100g, 31 g / 100g, 31.5 g / 100g, 32 g / 100g, 32.5 g / 100g, 33 g / 100g, 33.5 g / 100g, 34 g / 100g, 34.5 g / 100g, or 35 g / 100g, etc.

[0026] In this invention, by selecting modified aluminum hydroxide with a specific oil absorption value, the overall performance of the flame-retardant sealant can be further improved. If the oil absorption value of the modified aluminum hydroxide is too low, the viscosity of the flame-retardant sealant will be low, its thixotropy will be poor, and the sealant will easily sag after application, which is not conducive to construction. If the oil absorption value of the modified aluminum hydroxide is too high, the viscosity of the prepared flame-retardant sealant will be too high, its extrudability will be poor, which is not conducive to application, and the mechanical properties of the flame-retardant sealant after curing will also be poor.

[0027] Preferably, the filler also includes silica powder.

[0028] Preferably, the weight percentage of silica powder in the flame-retardant sealant is 20-50 parts, for example, 20 parts, 22 parts, 25 parts, 27 parts, 30 parts, 33 parts, 36 parts, 38 parts, 40 parts, 42 parts, 44 parts, 46 parts, 48 ​​parts, or 50 parts.

[0029] Preferably, the viscosity of the silane-modified polyether polymer at 23°C is 10,000 mPa·s - 30,000 mPa·s, for example, it can be 10,000 mPa·s, 12,000 mPa·s, 14,000 mPa·s, 16,000 mPa·s, 18,000 mPa·s, 20,000 mPa·s, 22,000 mPa·s, 24,000 mPa·s, 26,000 mPa·s, 28,000 mPa·s, or 30,000 mPa·s, etc.

[0030] Preferably, the silane-modified polyether polymer comprises a trimethoxysilane-terminated polyether resin;

[0031] In this invention, the trimethoxysilane-terminated polyether resins include, but are not limited to: Link-Shine 2400 and Link-Shine 1800 purchased from Shandong Lingxiao Chemical Co., Ltd., 308E and 258E purchased from Nanjing Qingqi New Materials Co., Ltd., and SAX400 purchased from Shanghai Zhonghua Trading Co., Ltd.

[0032] Preferably, the average particle size of the fumed silica is 10-15 nm, for example, it can be 10 nm, 11 nm, 12 nm, 13 nm, 14 nm or 15 nm, etc.

[0033] In this invention, fumed silica includes, but is not limited to, R-974 purchased from Evonik and LM-150 purchased from Cabot.

[0034] Preferably, the thixotropic agent comprises polyamide wax.

[0035] Preferably, the dehydrating agent comprises vinyltrimethoxysilane and / or vinyltriethoxysilane.

[0036] Preferably, the silane coupling agent is selected from any one or a combination of at least two of the following: 3-(2,3-epoxypropoxy)propyltrimethoxysilane (KH560), γ-glycidoxypropyltriethoxysilane, γ-aminopropyltriethoxysilane, γ-aminopropyltrimethoxysilane, N-(β-aminoethyl)-γ-aminopropyltrimethoxysilane, N-(β-aminoethyl)-γ-aminopropylmethyldimethoxysilane, oligomeric bisaminosilane, multifunctional aminosilane oligomers, triaminotrimethoxysilane, and bis(trimethoxysilylpropyl)amine.

[0037] Preferably, the curing agent is selected from any one or a combination of at least two of bis(acetylacetonate)dibutyltin, dibutyltin dilaurate, dibutylbis(2,4-glutarate-O,O′)-(OC-6-11)-tin, tetraethyl silicate, and bis(acetoxy)dibutyltinane.

[0038] Preferably, the flame-retardant sealant further includes 0.1 to 25 parts by weight of pigment, for example, 0.1, 0.5, 1, 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, or 25 parts by weight.

[0039] Preferably, the pigment includes carbon black or titanium dioxide.

[0040] Preferably, the flame-retardant sealant further includes 9-15 parts by weight of additives, such as 9 parts by weight, 10 parts by weight, 11 parts by weight, 12 parts by weight, 13 parts by weight, 14 parts by weight, or 15 parts by weight.

[0041] Preferably, the additives include any one or a combination of at least two of ultraviolet absorbers, light stabilizers, and antioxidants.

[0042] Preferably, the flame-retardant sealant further comprises the following components in parts by weight: 3-5 parts of ultraviolet absorber, 3-5 parts of light stabilizer, and 3-5 parts of antioxidant.

[0043] The weight percentage of the ultraviolet absorber in the flame-retardant sealant can be 3 parts, 3.2 parts, 3.4 parts, 3.6 parts, 3.8 parts, 4 parts, 4.2 parts, 4.4 parts, 4.6 parts, 4.8 parts, or 5 parts, etc.

[0044] The weight percentage of light stabilizer in the flame-retardant sealant can be 3 parts, 3.2 parts, 3.4 parts, 3.6 parts, 3.8 parts, 4 parts, 4.2 parts, 4.4 parts, 4.6 parts, 4.8 parts, or 5 parts, etc.

[0045] The antioxidant in the flame-retardant sealant can be in the following weight proportions: 3 parts, 3.2 parts, 3.4 parts, 3.6 parts, 3.8 parts, 4 parts, 4.2 parts, 4.4 parts, 4.6 parts, 4.8 parts, or 5 parts, etc.

[0046] Preferably, the ultraviolet absorber is selected from any one or a combination of at least two of 2-(2'-hydroxy-3'-tert-butyl-5'-methylphenyl)-5-chlorobenzotriazole, 2-(2'-hydroxy-3',5'-di-tert-butylphenyl)-5-chlorobenzotriazole, 2-(2'-hydroxy-3',5'-di-tert-pentylphenyl)benzotriazole, 2-(2'-hydroxy-5'-tert-octylphenyl)benzotriazole, and 2-(2'-hydroxy-3',5'-di-tert-butylphenyl)benzotriazole.

[0047] Preferably, the light stabilizer comprises any one or a combination of at least two of the following: bis(1,2,2,6,6-pentamethyl-4-piperidinyl) sebacate, bis(1-octoxy-2,2,6,6-tetramethyl-4-piperidinyl) sebacate, bis(2,2,6,6-tetramethyl-4-piperidinyl) sebacate, poly(1-hydroxyethyl-2,2,6,6-tetramethyl-4-hydroxypiperidinyl) succinate, and poly{[6-[(1,1,3,3-tetramethylbutyl)amino]]-1,3,5-triazine-2,4-[(2,2,6,6-tetramethyl-piperidinyl)imino]-1,6-hexamethylene[(2,2,6,6-tetramethyl-4-piperidinyl)imino]}.

[0048] The antioxidants include any one or a combination of at least two of the following: glycol bis-3-(3-tert-butyl-4-hydroxy-5-methylphenyl)propionate, pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], octadecyl β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, diethylene thiobis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], and tris[2,4-di-tert-butylphenyl]phosphite.

[0049] In a second aspect, the present invention provides a method for preparing a flame-retardant sealant as described in the first aspect, the method comprising the following steps: mixing the components of the flame-retardant sealant to obtain the flame-retardant sealant.

[0050] Preferably, the preparation method includes the following steps:

[0051] (1) Mix silane-modified polyether resin, plasticizer, filler, fumed silica, thixotropic agent, optional pigment, and optional additives to obtain a first mixture;

[0052] (2) The first mixture is dehydrated to obtain the second mixture;

[0053] (3) The second mixture is mixed with a dehydrating agent to obtain a third mixture;

[0054] (4) Mix the third mixture with a silane coupling agent to obtain a fourth mixture;

[0055] (5) The fourth mixture is mixed with the curing agent to obtain the flame retardant sealant.

[0056] Preferably, the mixing in step (1) is carried out under vacuum conditions.

[0057] Preferably, the mixing method in step (1) includes high-speed dispersion, wherein the high-speed dispersion speed is 900-1000 rpm, for example, it can be 900 rpm, 910 rpm, 920 rpm, 930 rpm, 940 rpm, 950 rpm, 960 rpm, 970 rpm, 980 rpm, 990 rpm or 1000 rpm, etc.

[0058] Preferably, the dehydration temperature in step (2) is 110-130℃ (e.g., 110℃, 112℃, 114℃, 116℃, 118℃, 120℃, 122℃, 124℃, 126℃, 128℃ or 130℃, etc.), and the time is 1-3 h (e.g., 1 h, 1.5 h, 2 h, 2.5 h or 3 h, etc.).

[0059] Preferably, the dehydration is carried out under vacuum conditions.

[0060] Preferably, the water content of the second mixture is ≤400 ppm, for example, it can be 200 ppm, 220 ppm, 240 ppm, 260 ppm, 280 ppm, 300 ppm, 320 ppm, 340 ppm, 360 ppm, 380 ppm or 400 ppm, etc.

[0061] Compared with the prior art, the present invention has the following beneficial effects:

[0062] (1) This invention designs the specific composition of the flame retardant sealant, uses modified aluminum hydroxide as a flame retardant, combines it with a specific plasticizer, and then combines it with other components. Without using phosphorus-based flame retardants, a flame retardant sealant with good flame retardancy and good mechanical properties is prepared, and the manufacturing cost is relatively low, which is more conducive to large-scale commercial production.

[0063] (2) The present invention preferably uses polyether plasticizers, which further improves the overall performance of flame retardant sealant.

[0064] (3) The present invention preferably uses modified aluminum hydroxide with a specific oil absorption value, which can further improve the overall performance of flame retardant sealant. Detailed Implementation

[0065] To facilitate understanding of the present invention, the following embodiments are provided. Those skilled in the art should understand that these embodiments are merely illustrative and should not be construed as limiting the scope of the invention.

[0066] The sources of some components in the examples and comparative examples are shown in Table 1 below:

[0067] Table 1

[0068]

[0069]

[0070] Example 1

[0071] This embodiment provides a flame-retardant sealant and its preparation method. The flame-retardant sealant comprises the following components in parts by weight: 85 parts of silane-modified polyether polymer (Link-Shine 1800), 200 parts of silane-modified polyether polymer (Link-Shine 2400), 100 parts of plasticizer (polyether C2020), 2650 parts of modified aluminum hydroxide, 3 parts of ultraviolet absorber, 3 parts of light stabilizer, 3 parts of antioxidant, 30 parts of fumed silica, 10 parts of polyamide wax, 15 parts of vinyltrimethoxysilane, 5 parts of 3-(2,3-epoxypropoxy)propyltrimethoxysilane, 15 parts of N-(β-aminoethyl)-γ-aminopropyltrimethoxysilane, and 2 parts of bis(acetylacetonate)dibutyltin.

[0072] The preparation method of the above flame-retardant sealant is as follows:

[0073] (1) Silane-modified polyether resin, plasticizer, modified aluminum hydroxide 2, fumed silica, polyamide wax, ultraviolet absorber, light stabilizer and antioxidant are dispersed and mixed at high speed under vacuum and rotation speed of 1000 rpm to obtain the first mixture;

[0074] (2) The first mixture was dehydrated under vacuum and 120°C for 2 h to obtain a second mixture with a water content ≤400ppm;

[0075] (3) Mix the second mixture with vinyltrimethoxysilane until homogeneous to obtain the third mixture;

[0076] (4) Mix the third mixture with 3-(2,3-epoxypropoxy)propyltrimethoxysilane and N-(β-aminoethyl)-γ-aminopropyltrimethoxysilane to obtain the fourth mixture;

[0077] (5) After the fourth mixture is mixed evenly with bis(acetylacetonate) dibutyltin, the flame retardant sealant is obtained.

[0078] Example 2

[0079] This embodiment provides a flame-retardant sealant and its preparation method. The flame-retardant sealant comprises the following components in parts by weight: 135 parts of silane-modified polyether polymer (Link-Shine 1800), 135 parts of silane-modified polyether polymer (Link-Shine 2400), 90 parts of plasticizer (MESAMOLL), 1625 parts of modified aluminum hydroxide, 25 parts of silica powder, 0.1 parts of carbon black, 3 parts of ultraviolet absorber, 3 parts of light stabilizer, 3 parts of antioxidant, 30 parts of fumed silica, 10 parts of polyamide wax, 15 parts of vinyltrimethoxysilane, 5 parts of 3-(2,3-epoxypropoxy)propyltrimethoxysilane, 15 parts of N-(β-aminoethyl)-γ-aminopropyltrimethoxysilane, and 2 parts of bis(acetylacetonate)dibutyltin.

[0080] The preparation method of the above flame-retardant sealant is as follows:

[0081] (1) Silane-modified polyether resin, plasticizer, modified aluminum hydroxide 1, silica powder, pigment, fumed silica, thixotropic agent, ultraviolet absorber, light stabilizer and antioxidant are dispersed and mixed at high speed under vacuum and at a speed of 900 rpm to obtain the first mixture.

[0082] (2) The first mixture was dehydrated under vacuum and 120°C for 2 h to obtain a second mixture with a water content ≤400ppm;

[0083] (3) Mix the second mixture with vinyltrimethoxysilane until homogeneous to obtain the third mixture;

[0084] (4) Mix the third mixture 3-(2,3-epoxypropoxy)propyltrimethoxysilane and N-(β-aminoethyl)-γ-aminopropyltrimethoxysilane evenly to obtain the fourth mixture;

[0085] (5) After the fourth mixture is mixed evenly with bis(acetylacetonate) dibutyltin, the flame retardant sealant is obtained.

[0086] Example 3

[0087] This embodiment provides a flame-retardant sealant and its preparation method. The flame-retardant sealant comprises the following components in parts by weight: 270 parts of silane-modified polyether polymer (SAX400), 90 parts of plasticizer (MESAMOLL), 2625 parts of modified aluminum hydroxide, 25 parts of silica powder, 0.1 parts of carbon black, 3 parts of ultraviolet absorber, 3 parts of light stabilizer, 3 parts of antioxidant, 30 parts of fumed silica, 20 parts of polyamide wax, 10 parts of vinyltrimethoxysilane, 5 parts of 3-(2,3-epoxypropoxy)propyltrimethoxysilane, 15 parts of N-(β-aminoethyl)-γ-aminopropyltrimethoxysilane, and 2 parts of bis(acetylacetonate)dibutyltin.

[0088] The preparation method of the above flame-retardant sealant is as described in Example 2.

[0089] Example 4

[0090] This embodiment provides a flame-retardant sealant and its preparation method. The flame-retardant sealant comprises the following components in parts by weight: 300 parts of silane-modified polyether polymer (308E), 120 parts of plasticizer (polyether C2020), 2560 parts of modified aluminum hydroxide, 20 parts of titanium dioxide, 4 parts of ultraviolet absorber, 4 parts of light stabilizer, 4 parts of antioxidant, 20 parts of fumed silica, 15 parts of polyamide wax, 28 parts of vinyltrimethoxysilane, 8 parts of 3-(2,3-epoxypropoxy)propyltrimethoxysilane, and 4 parts of bis(acetylacetonate)dibutyltin.

[0091] The preparation method of the above flame-retardant sealant is as described in Example 2.

[0092] Example 5

[0093] This embodiment provides a flame-retardant sealant and its preparation method. The flame-retardant sealant comprises the following components in parts by weight: 255 parts of silane-modified polyether polymer (Link-Shine 1800), 110 parts of plasticizer (polyether C2020), 2600 parts of modified aluminum hydroxide, 10 parts of silica powder, 0.1 parts of carbon black, 5 parts of ultraviolet absorber, 5 parts of light stabilizer, 5 parts of antioxidant, 50 parts of fumed silica, 18 parts of polyamide wax, 12 parts of vinyltrimethoxysilane, 15 parts of N-(β-aminoethyl)-γ-aminopropyltrimethoxysilane, and 3 parts of bis(acetylacetonate)dibutyltin.

[0094] The preparation method of the above flame-retardant sealant is as described in Example 1.

[0095] Example 6

[0096] This embodiment provides a flame-retardant sealant and its preparation method. The only difference from Embodiment 1 is that the modified aluminum hydroxide 2 is replaced with an equal weight of modified aluminum hydroxide 1, and the other conditions are the same as in Embodiment 1.

[0097] Example 7

[0098] This embodiment provides a flame-retardant sealant and its preparation method. The only difference from Embodiment 1 is that the modified aluminum hydroxide 2 is replaced with an equal weight of modified aluminum hydroxide 3, and the other conditions are the same as in Embodiment 1.

[0099] Example 8

[0100] This embodiment provides a flame-retardant sealant and its preparation method. The only difference from Embodiment 1 is that the modified aluminum hydroxide 2 is replaced with an equal weight of modified aluminum hydroxide A, and the other conditions are the same as in Embodiment 1.

[0101] Example 9

[0102] This embodiment provides a flame-retardant sealant and its preparation method. The only difference from Embodiment 1 is that modified aluminum hydroxide 2 is replaced with an equal weight of modified aluminum hydroxide B, while other conditions are the same as in Embodiment 1.

[0103] Example 10

[0104] This embodiment provides a flame-retardant sealant and its preparation method. The only difference from Embodiment 1 is that the plasticizer (polyether C2020) is replaced with an equal weight amount of plasticizer (polyether 2000), and the other conditions are the same as in Embodiment 1.

[0105] Example 11

[0106] This embodiment provides a flame-retardant sealant and its preparation method. The only difference from Example 1 is that the plasticizer (polyether C2020) is replaced with an equal weight amount of plasticizer (diisodecyl phthalate), and the other conditions are the same as in Example 1.

[0107] Example 12

[0108] This embodiment provides a flame-retardant sealant and its preparation method. The only difference from Example 1 is that the weight of the plasticizer (polyether C2020) is adjusted to 90 parts, while other conditions are the same as in Example 1.

[0109] Example 13

[0110] This embodiment provides a flame-retardant sealant and its preparation method. The only difference from Embodiment 1 is that the weight of the plasticizer (polyether C2020) is adjusted to 120 parts, while other conditions are the same as in Embodiment 1.

[0111] Comparative Example 1

[0112] This comparative example provides a flame-retardant sealant and its preparation method. The only difference from Example 1 is that the weight of the plasticizer (polyether C2020) is adjusted to 80 parts, while other conditions are the same as in Example 1.

[0113] Comparative Example 2

[0114] This comparative example provides a flame-retardant sealant and its preparation method. The only difference from Example 1 is that the weight of the plasticizer (polyether C2020) is adjusted to 140 parts, while other conditions are the same as in Example 1.

[0115] Comparative Example 3

[0116] This comparative example provides a flame-retardant sealant and its preparation method. The only difference from Example 1 is that the modified aluminum hydroxide 2 is replaced with an equal amount of aluminum hydroxide by weight, while the other conditions are the same as in Example 1.

[0117] Comparative Example 4

[0118] This comparative example provides a flame-retardant sealant and its preparation method. The only difference from Example 1 is that the thixotropic polyamide wax is not used, while the other conditions are the same as in Example 1.

[0119] Comparative Example 5

[0120] This comparative example provides a flame-retardant sealant and its preparation method. The only difference from Example 1 is that 100 parts by weight of plasticizer (polyether C2020) is replaced with 60 parts by weight of plasticizer (polyether C2020) and 60 parts by weight of plasticizer (phosphate ester HF-4). Other conditions are the same as in Example 1.

[0121] The performance of the flame-retardant sealants provided in the above embodiments and comparative examples was tested, and the specific test methods are as follows:

[0122] Flame retardant rating: Based on UL94 V-0;

[0123] Surface drying time (min): Refer to GB / T 13477.5-2003 Part 5 Determination of surface drying time;

[0124] Curing speed (24 h / mm): Refer to GB / T 32369-2015 Determination of curing degree of sealant;

[0125] Hardness: Refer to GB / T 531.1-2008 Test method for indentation hardness of vulcanized rubber or thermoplastic rubber - Part 1: Shore hardness tester method (Shore hardness);

[0126] Viscosity (mPa·s): Refer to GB / T 2794-2022 "Determination of Viscosity of Adhesives";

[0127] Tensile strength (MPa): Refer to GB / T 528-2009 Determination of tensile stress-strain properties of vulcanized rubber or thermoplastic rubber;

[0128] Elongation at break (%): Refer to GB / T 528-2009 Determination of tensile stress-strain properties of vulcanized rubber or thermoplastic rubber;

[0129] Carbon steel shear strength (MPa): Refer to GB / T 7124 / 2008 Determination of tensile shear strength of adhesives (rigid material to rigid material).

[0130] The above performance tests are detailed in Table 2 below:

[0131] Table 2

[0132]

[0133] As described above, this invention designs the specific composition of the flame-retardant sealant, using modified aluminum hydroxide as a flame retardant, combined with a specific plasticizer, and then blending it with other components. Without using phosphorus-based flame retardants, this invention prepares a flame-retardant sealant that possesses both good flame retardancy and mechanical properties, while also having relatively low manufacturing costs, making it more suitable for large-scale commercial production. The flame-retardant sealant provided by this invention has a flame retardancy rating of V0, a ​​surface drying time of 3-11 min, a curing speed of 2.0-3.0 (24 h / mm), a hardness of 60-78, an annual strength of 115000-196000 mPa·s, a tensile strength of 2.35-3.75 MPa, an elongation at break of 48-105%, and a carbon steel shear strength of 2.15-3.10 MPa.

[0134] As can be seen from Examples 1 and 6-9, the present invention preferably uses modified aluminum hydroxide with a specific oil absorption value, which can further improve the overall performance of the flame retardant sealant.

[0135] As can be seen from Examples 1-5, Examples 10-11 and Comparative Example 5, the present invention preferably uses polyether plasticizers, which can further improve the overall performance of flame retardant sealants.

[0136] As can be seen from Examples 1, 12-13 and Comparative Examples 1-2, the present invention prepares a flame-retardant sealant with good flame retardancy and good mechanical properties by controlling the amount of plasticizer within a specific range.

[0137] As can be seen from the comparison of Example 1 and Comparative Examples 3-5, the present invention designs the specific composition of the flame-retardant sealant, uses modified aluminum hydroxide as a flame retardant, combines it with a specific plasticizer, and then combines it with other components, so that a flame-retardant sealant with good flame retardancy and good mechanical properties can be prepared without using phosphorus-based flame retardants.

[0138] The applicant declares that the detailed process flow of this invention is illustrated by the above embodiments, but this invention is not limited to the above detailed process flow, that is, it does not mean that this invention must rely on the above detailed process flow to be implemented. Those skilled in the art should understand that any improvements to this invention, equivalent substitutions of raw materials for the product of this invention, addition of auxiliary components, and selection of specific methods, etc., all fall within the protection scope and disclosure scope of this invention.

Claims

1. A fire-retardant sealant, characterized by, The fire-retardant sealant comprises components in the following weight proportions: 250-300 parts of silane-modified polyether type polymer, 90-120 parts of plasticizer, 550-650 parts of filler, 20-50 parts of fumed white carbon black, 10-15 parts of thixotropic agent, 10-30 parts of water removal agent, 5-20 parts of silane coupling agent and 1.5-5 parts of curing agent; The plasticizer is selected from any one or a combination of at least two of diisodecyl phthalate, diisononyl phthalate, polyether plasticizer, alkyl benzene sulfonate; The filler comprises modified aluminum hydroxide.

2. The fire-retardant sealant of claim 1, wherein The polyether plasticizer is selected from polyether C2020 and / or polyether 2000; Preferably, the plasticizer is a polyether plasticizer.

3. The flame-retardant sealant according to claim 1 or 2, characterized in that, The D50 particle size of the modified aluminum hydroxide is 3 μm - 10 μm; Preferably, the whiteness of the modified aluminum hydroxide is 99.5%±0.5%; Preferably, the oil absorption value of the modified aluminum hydroxide is 30 g / 100g - 35 g / 100g; Preferably, the filler further comprises silicon powder; Preferably, the weight proportion of silicon powder in the fire-retardant sealant is 20-50 parts.

4. The fire-retardant sealant according to any one of claims 1 to 3, characterized in that The viscosity of the silane-modified polyether type polymer at 23℃ is 10000 mPa·s - 30000 mPa·s; Preferably, the silane-modified polyether type polymer comprises trimethoxysilane-terminated polyether resin; Preferably, the average particle size of the fumed white carbon black is 10-15 nm; Preferably, the thixotropic agent comprises polyamide wax; Preferably, the water removal agent comprises vinyl trimethoxysilane and / or vinyl triethoxysilane.

5. The fire-retardant sealant according to any one of claims 1-4, wherein the fire-retardant sealant comprises: The silane coupling agent is selected from any one or a combination of at least two of 3-(2,3-epoxypropoxy)propyl trimethoxysilane, γ-glycidyloxypropyl triethoxysilane, γ-aminopropyl triethoxysilane, γ-aminopropyl trimethoxysilane, N-(β-aminoethyl)-γ-aminopropyl trimethoxysilane, N-(β-aminoethyl)-γ-aminopropyl methyl dimethoxysilane, oligomeric bisamino silane, multifunctional amino silane oligomer, triaminotrimethoxysilane, bis(trimethoxysilylpropyl)amine; Preferably, the curing agent is selected from any one or a combination of at least two of dibutyltin bis(acetylacetate), dibutyltin dilaurate, dibutylbis(2,4-pentanedionate-O,O')-(OC-6-11)-tin, tetraethyl silicate and bis(acetyloxy) dibutyl tinane.

6. The fire-retardant sealant according to any one of claims 1-5, wherein the fire-retardant sealant comprises: The fire-retardant sealant further comprises 0.1 parts-25 parts by weight of pigment; Preferably, the pigment comprises carbon black or titanium white powder; Preferably, the fire-retardant sealant further comprises 9-15 parts by weight of auxiliary; Preferably, the auxiliary comprises any one or a combination of at least two of ultraviolet absorber, light stabilizer, antioxidant; Preferably, the fire-retardant sealant further comprises components in the following weight proportions: 3-5 parts of ultraviolet absorber, 3-5 parts of light stabilizer, 3-5 parts of antioxidant.

7. The fire-retardant sealant of claim 6, wherein The ultraviolet absorber is selected from any one or a combination of at least two of 2-(2'-hydroxy-3'-tert-butyl-5'-methylphenyl)-5-chlorobenzotriazole, 2-(2'-hydroxy-3',5'-di-tert-butylphenyl)-5-chlorobenzotriazole, 2-(2'-hydroxy-3',5'-di-tert-amylphenyl)benzotriazole, 2-(2'-hydroxy-5'-tert-octylphenyl)benzotriazole, 2-(2'-hydroxy-3',5'-di-tert-butylphenyl)benzotriazole; Preferably, the light stabilizer comprises any one or a combination of at least two of bis(1,2,2,6,6-pentamethyl-4-piperidyl)sebacate, bis(1-octyloxy-2,2,6,6-tetramethyl-4-piperidyl)sebacate, bis(2,2,6,6-tetramethyl-4-piperidyl)sebacate, poly(1-hydroxyethyl-2,2,6,6-tetramethyl-4-hydroxypiperidine)butanedioate, poly{[6-[(1,1,3,3-tetramethylbutyl)amino]]-1,3,5-triazine-2,4-[(2,2,6,6-tetramethyl-piperidyl)imino]-1,6-hexanediyl[(2,2,6,6-tetramethyl-4-piperidyl)imino]}. The antioxidant comprises any one or a combination of at least two of glycol bis-3-(3-tert-butyl-4-hydroxy-5-methylphenyl)propionate, pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], octadecyl β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, thiodiethylene bis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], tris[2,4-di-tert-butylphenyl]phosphite.

8. A process for the preparation of a fire-retardant sealant as claimed in any one of claims 1 to 7, characterized in that, The preparation method comprises the following steps: Mixing the components of the fire-retardant sealant to obtain the fire-retardant sealant.

9. The production method according to claim 8, characterized by, The preparation method comprises the following steps: (1) mixing the silane-modified polyether resin, the plasticizer, the filler, the fumed white carbon black, the thixotropic agent, the optional pigment, and the optional auxiliary agent to obtain a first mixture; (2) performing dehydration treatment on the first mixture to obtain a second mixture; (3) mixing the second mixture with a water removal agent to obtain a third mixture; (4) mixing the third mixture with a silane coupling agent to obtain a fourth mixture; (5) mixing the fourth mixture with a curing agent to obtain the fire-retardant sealant.

10. The method of claim 9, wherein, The mixing in step (1) is performed under vacuum; Preferably, the mixing method in step (1) comprises high-speed dispersion, and the rotation speed of the high-speed dispersion is 900-1000 rpm; Preferably, the dehydration temperature in step (2) is 110-130°C, and the time is 1-3 h; Preferably, the dehydration is performed under vacuum; Preferably, the water content of the second mixture is ≤400 ppm.

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