Modifier composition for improving application performance of flame retardant and application of modifier composition

Abstract

The invention relates to a modifier composition for improving the application performance of a flame retardant and application of the modifier composition. The invention relates to a water-based paint which comprises a weak hydrophobic modifier and a strong hydrophobic modifier in a mass ratio of 1: (0.5-2), the weak hydrophobic modifier is combined with a hydroxyl group on the surface of magnesium hydroxide through a hydrophilic group of the weak hydrophobic modifier, so that primary dispersion and surface weak hydrophobization of the flame retardant are realized; the strong hydrophobic modifier forms a stable coating layer on the surface of the weakly hydrophobized magnesium hydroxide through a long-chain hydrophobic group, so that the surface energy is reduced and agglomeration is prevented; the flame retardant efficiency and the mechanical property of the magnesium hydroxide flame retardant are improved through the independent action and the synergistic effect of the weak hydrophobic modifier and the strong hydrophobic modifier. Through molecular collaborative design of weak hydrophobic-strong hydrophobic dual-functional components, the system breaks through the problems of flame retardance and mechanical properties caused by poor modification effect due to traditional single modification, and realizes optimal balance of flame retardance efficiency and mechanical properties.

Description

Technical Field

[0001] The present invention relates to the technical field of flame retardant materials, and in particular to a group of modifier combinations for improving the application performance of flame retardants and applications thereof. Background Art

[0002] Magnesium hydroxide is a white or off-white crystalline powder. As an environmentally friendly flame retardant, it has excellent flame retardancy and smoke suppression properties. It is also low-priced and has a higher decomposition temperature. Its application range is wider than that of aluminum hydroxide, and it will occupy a very important position in the future flame retardant market. Magnesium hydroxide flame retardant has outstanding flame retardant properties such as non-toxicity, smoke suppression, and environmental protection. However, the amount of magnesium hydroxide required for use is relatively large. Furthermore, the hydrophilic and oleophobic surface of magnesium hydroxide, its high polarity, and its tendency to agglomerate make it less compatible and dispersible in polymer materials, which directly leads to a serious deterioration in the mechanical properties of the materials. This greatly limits the scope of use of magnesium hydroxide flame retardant.

[0003] In order to improve the compatibility and dispersibility of magnesium hydroxide with polymers, magnesium hydroxide must be surface modified. However, attempts have been made in the prior art to solve these problems through surface modification optimization, but there are still shortcomings such as single surface modification. Single surface modification makes the modified magnesium hydroxide flame retardant functional synergy poor. For example, single modification with a surfactant is used to improve hydrophobicity by physical coating, but the surfactant has weak binding force with the surface of magnesium hydroxide and is easily desorbed during high-temperature processing, resulting in a decrease in flame retardant efficiency. Alternatively, only silane coupling agents are used for surface grafting. Although this improves compatibility with polymers, the overall performance is still limited. Therefore, there is an urgent need for a group of modifier combinations that can effectively improve the flame retardant properties and mechanical properties of the entire material. Summary of the Invention

[0004] The object of the present invention is to solve at least one of the above technical problems. By cleverly combining a weak hydrophobic modifier with a strong hydrophobic modifier, the problem that the prior art only uses a single modifier for modification, resulting in poor modification effect of the magnesium hydroxide flame retardant and poor overall performance of the flame retardant is overcome.

[0005] The present invention provides a modifier combination for improving the application performance of a flame retardant, comprising a weakly hydrophobic modifier and a strongly hydrophobic modifier, wherein the mass ratio of the weakly hydrophobic modifier to the strongly hydrophobic modifier is 1:(0.5-2).

[0006] Furthermore, the weakly hydrophobic modifier combines with the hydroxyl groups on the surface of magnesium hydroxide through its hydrophilic groups to achieve preliminary dispersion of the flame retardant and weak surface hydrophobization;

[0007] The strong hydrophobic modifier forms a stable coating layer on the surface of the activated magnesium hydroxide through long-chain hydrophobic groups, thereby reducing surface energy and preventing agglomeration;

[0008] Through the independent action and synergistic effect of the weak hydrophobic modifier and the strong hydrophobic modifier, the gradient distribution of the magnesium hydroxide flame retardant in the polymer matrix is ​​achieved, thereby improving the flame retardant efficiency and mechanical properties;

[0009] Preferably, the number of carbon atoms of the weak hydrophobic modifier is ≤5, and the number of carbon atoms of the strong hydrophobic modifier is ≥8;

[0010] Preferably, the weak hydrophobic modifier is selected from at least one of a surfactant or a silane coupling agent; and the strong hydrophobic modifier is selected from at least one of an organosilicon modifier or a silicone oil hydrophobic modifier.

[0011] Furthermore, the surfactant is selected from at least one of anionic surfactants and nonionic surfactants.

[0012] Furthermore, the surfactant is selected from at least one of sodium butyrate, sodium succinate, sodium propionate, sodium butyl sulfonate, polyoxyethylene fatty acid ester, sorbitan fatty acid ester, monoglycerol fatty acid ester, diglycerol fatty acid ester, and triglycerol fatty acid ester.

[0013] Furthermore, the silane coupling agent is selected from at least one of an aminosilane coupling agent or an epoxysilane coupling agent;

[0014] Preferably, the aminosilane coupling agent comprises at least one amino functional group;

[0015] Preferably, the epoxy silane coupling agent comprises at least one epoxy functional group.

[0016] Furthermore, the silicone oil hydrophobic modifier is selected from at least one of methyl silicone oil, ethyl silicone oil, toluene silicone oil, and fatty acid-modified silicone oil.

[0017] Furthermore, the organosilicon modifier is selected from at least one of dodecylphenyltrimethoxysilane, hexadecyltrimethoxysilane, polydimethylsiloxane, and hydroxyl-terminated polydimethylsiloxane.

[0018] The present invention also provides a group of use of a modifier combination in preparing a flame retardant, including the above-mentioned modifier combination.

[0019] Furthermore, the flame retardant includes magnesium hydroxide flame retardant.

[0020] Furthermore, the application method of the modifier combination comprises the following steps:

[0021] (1) adding a weak hydrophobic modifier to the magnesium hydroxide suspension for weak hydrophobic modification, wherein the weak hydrophobic modifier is combined with the surface hydroxyl group of the magnesium hydroxide through a hydrophilic group to complete preliminary dispersion and surface weak hydrophobization, and the modified suspension is dried;

[0022] (2) A strong hydrophobic modifier is used to perform secondary modification on the magnesium hydroxide powder dried in step 1), wherein the strong hydrophobic modifier forms a stable coating layer on the surface of the activated magnesium hydroxide through long-chain hydrophobic groups, thereby reducing the surface energy and preventing agglomeration, and finally obtaining a magnesium hydroxide flame retardant with gradient distribution characteristics.

[0023] Compared with the prior art, the advantages of the present invention are:

[0024] The present invention provides a combination of modifiers that can be used to control the surface properties of magnesium hydroxide. This is achieved through the molecular synergistic design of a weakly hydrophobic and strongly hydrophobic bifunctional component. Based on the mass ratio of the weakly hydrophobic agent to the strong hydrophobic agent, the surface weak hydrophobicization of the weakly hydrophobic end and the organosilicon modifier at the hydrophobic end form a complementary system. The two work together to achieve a gradient dispersion of the flame retardant in the polymer matrix, ensuring that the modified layer remains stable during high-temperature processing and achieving an optimal balance between flame retardancy and mechanical properties.

[0025] Specific implementation methods

[0026] To make the purpose, technical solutions and advantages of this application more clear, this application is further described in detail below. However, it should be understood that the description herein is only used to explain this application and is not intended to limit the scope of this application.

[0027] Unless otherwise defined, all technical and scientific terms used herein have the same meanings as those commonly understood by those skilled in the art to which this application pertains. The terms used herein in the specification of this application are intended solely for the purpose of describing specific embodiments and are not intended to limit this application. The reagents and instruments used herein are commercially available, and the characterization methods involved can be found in the relevant descriptions in the prior art and will not be further elaborated herein.

[0028] In order to further understand the present application, the present application is further described in detail below in conjunction with the best embodiment.

[0029] Example 1

[0030] The present embodiment provides a group of modifier combinations for improving the application performance of flame retardants, comprising a weak hydrophobic modifier and a strong hydrophobic modifier, wherein the mass ratio of the weak hydrophobic modifier to the strong hydrophobic modifier is 1:(0.5-2), for example, it can be 1:0.5, 1:0.6, 1:0.7, 1:0.8, 1:0.9, 1:1, 1:1.1, 1:1.2, 1:1.3, 1:1.4, 1:1.5, 1:1.7, 1:1.8, 1:1.9, 1:2 or any value between any two values.

[0031] As a further preferred embodiment, the weakly hydrophobic modifier combines with the hydroxyl groups on the surface of magnesium hydroxide through its hydrophilic group to achieve preliminary dispersion of the flame retardant and weak surface hydrophobization;

[0032] The strong hydrophobic modifier forms a stable coating layer on the surface of the activated magnesium hydroxide through long-chain hydrophobic groups, thereby reducing surface energy and preventing agglomeration;

[0033] Through the independent action and synergistic effect of the weak hydrophobic modifier and the strong hydrophobic modifier, the gradient distribution of the magnesium hydroxide flame retardant in the polymer matrix is ​​achieved, thereby improving the flame retardant efficiency and mechanical properties;

[0034] Weakly hydrophobic modifiers can be attached to the surface of materials through chemical or physical methods, thereby changing the original surface properties of the material and increasing its hydrophobic properties.

[0035] A strong hydrophobic modifier is a chemical that can make a material surface hydrophobic. By using a strong hydrophobic modifier, a material that is not hydrophobic can be made waterproof, stain-resistant, and washable, thereby improving the material's service life and overall performance.

[0036] Preferably, the weak hydrophobic modifier is selected from at least one of a surfactant or a silane coupling agent; and the strong hydrophobic modifier is selected from at least one of an organosilicon modifier or a silicone oil hydrophobic modifier.

[0037] A surfactant is a substance that, when added in small amounts, can significantly alter the interfacial state of a solution. It possesses fixed, weakly hydrophobic and lipophilic groups that can be arranged in a directional pattern on the surface of a solution. The molecular structure of a surfactant is amphiphilic: one end has a weakly hydrophobic group, while the other has a hydrophobic group. The weakly hydrophobic group is often a polar group, such as carboxylic acid, sulfonic acid, sulfuric acid, amino or amine groups and their salts, hydroxyl groups, amide groups, and ether bonds; while the strongly hydrophobic group is often a non-polar hydrocarbon chain, such as one with eight or more carbon atoms. The primary function of a surfactant is to significantly reduce the surface tension or interfacial tension of a target solution.

[0038] Silane coupling agents are a class of organosilicon compounds containing silane groups and organic functional groups. The silane groups are reactive towards inorganic substances, while the organic functional groups are reactive or compatible towards organic substances, which enables silane coupling agents to form a bonding layer between inorganic and organic interfaces.

[0039] Therefore, the number of carbon atoms in a weak hydrophobic group is usually less than or equal to 5. The number of carbon atoms in a strong hydrophobic group is usually greater than or equal to 8.

[0040] If the weakly hydrophobic modifier is a surfactant and a silane coupling agent used in combination, the mass ratio thereof is 1:(0.1-10).

[0041] Silicone modifiers are chemical additives that improve or give new properties to materials by introducing other functional groups or polymer chains into silicone monomers. They are widely used and can significantly improve the material's heat resistance, weather resistance, electrical properties, and adhesion.

[0042] Silicone oil hydrophobic modifier is a commonly used strong hydrophobic modifier, mainly composed of silicone oil or its derivatives, and has excellent hydrophobic properties.

[0043] As a further preferred embodiment, the surfactant is selected from anionic or nonionic surfactants. Anionic surfactants are surfactants with a negative charge that acts as a surface active agent after ionization in water, while nonionic surfactants are surfactants whose molecules do not ionize after dissolving in water.

[0044] As a further preferred embodiment, the surfactant is selected from at least one of sodium butyrate, sodium succinate, sodium propionate, sodium butyl sulfonate, polyoxyethylene fatty acid esters, sorbitan fatty acid esters, monoglycerol fatty acid esters, diglycerol fatty acid esters, and triglycerol fatty acid esters.

[0045] Fatty acid polyoxyethylene ester is a nonionic surfactant with an appearance ranging from amber liquid to milky white solid. It is soluble in water, ethanol and higher fatty alcohols and has good surface activities such as emulsification, solubilization, wetting, dispersion, softening and antistatic.

[0046] Sorbitan fatty acid esters are nonionic surfactants, also known as spans. Sorbitan fatty acid esters are partial fatty acid esters of polyols and possess excellent emulsifying, dispersing, and lubricating properties. Their chemical structure allows them to function effectively in both water-in-oil and oil-in-water emulsifiers.

[0047] Monoglyceride is a compound composed of a glycerol molecule and a fatty acid molecule connected by an ester bond.

[0048] Diglycerol fatty acid ester is a compound composed of one glycerol molecule and two fatty acid molecules connected by an ester bond.

[0049] Triglyceride is a compound composed of one glycerol molecule and three fatty acid molecules connected by ester bonds.

[0050] As a further preferred embodiment, the silane coupling agent is selected from at least one of an aminosilane coupling agent or an epoxysilane coupling agent.

[0051] Aminosilane coupling agent has a unique chemical structure and properties, which can couple organic polymers and inorganic fillers, enhance their adhesion, and improve the mechanical, water resistance, and anti-aging properties of the product.

[0052] Epoxysilane coupling agent is a silane coupling agent with epoxy functional groups.

[0053] As a further preferred embodiment, the aminosilane coupling agent contains at least one amino functional group.

[0054] As a further preferred embodiment, the aminosilane coupling agent is selected from at least one of aminopropyltriethoxysilane, N-β-(aminoethyl)-γ-aminopropyltrimethoxysilane, γ-aminopropyltrimethoxysilane, and N-phenyl-γ-aminopropyltrimethoxysilane.

[0055] Aminopropyltriethoxysilane is typically a colorless or slightly yellowish transparent liquid, soluble in organic solvents such as benzene and ethyl acetate. It reacts with water to release ethanol, forming the corresponding silanol condensate. It possesses two different active groups: amino and ethoxy. The amino group reacts with a variety of compounds, such as acids, carboxylates, aldehydes, and ketones; the ethoxy group can be used to couple organic polymers and inorganic fillers, enhancing their adhesion and improving the product's mechanical, electrical, water-resistant, and anti-aging properties.

[0056] N-β-(Aminoethyl)-γ-aminopropyltrimethoxysilane is a colorless or slightly yellowish transparent liquid soluble in solvents such as ether and benzene. It reacts with acetone, carbon tetrachloride, and water. 1 It is primarily used to increase the adhesion of organic materials to inorganic substrates and is suitable for most organic and inorganic materials. It is particularly effective as an excellent adhesion promoter in silicone sealants, significantly improving their adhesion. It can also be used to enhance the mechanical strength, electrical properties, and aging resistance of composite materials, and is suitable for materials such as polyester resins, epoxy resins, and phenolic resins.

[0057] γ-Aminopropyltrimethoxysilane is an important silane coupling agent. It is a colorless or slightly yellowish transparent liquid that is soluble in solvents such as benzene and ethyl acetate and reacts with water. Its amino and methoxy groups are used to couple organic polymers and inorganic fillers, respectively, thereby enhancing their adhesion and improving the product's mechanical, electrical, water resistance, and aging resistance.

[0058] N-Phenyl-γ-aminopropyltrimethoxysilane is a colorless or pale yellow, transparent liquid compound that is insoluble in water but soluble in organic solvents such as benzene and ethyl acetate. It is primarily used as a silane coupling agent, enhancing the adhesion between organic polymers and inorganic fillers, improving the mechanical, electrical, water-resistant, and aging-resistant properties of composite materials. Furthermore, N-Phenyl-γ-aminopropyltrimethoxysilane exhibits excellent chemical and thermal stability, maintaining its properties under a variety of conditions. It also exhibits low toxicity and good biocompatibility.

[0059] As a further preferred embodiment, the epoxy silane coupling agent contains at least one epoxy functional group.

[0060] As a further preferred embodiment, the epoxy silane coupling agent is at least one selected from epoxy resin type water-based coupling agent, water-based silane coupling agent BP-563, and 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane.

[0061] Epoxy resin type water-based coupling agent is a coupling agent suitable for water-based epoxy resin system.

[0062] 2-(3,4-Epoxycyclohexyl)ethyltriethoxysilane is mainly used as a silane coupling agent, which can improve the binding force and compatibility of inorganic mineral powder materials and fibers to high molecular polymers and the adhesion of resin coatings to inorganic substrates.

[0063] As a further preferred embodiment, the silicone oil hydrophobic modifier is at least one selected from methyl silicone oil, ethyl silicone oil, toluene silicone oil, and fatty acid-modified silicone oil.

[0064] Methyl silicone oil is a colorless, odorless, non-volatile oil whose organic groups are all methyl groups. It has excellent heat resistance, electrical insulation, weather resistance and other characteristics, and is widely used in many fields.

[0065] Ethyl silicone oil is a colorless to light yellow transparent liquid, soluble in organic solvents such as toluene, ether, chloroform, etc., and can be mixed with petroleum products at will.

[0066] Toluene-based silicone oil is a colorless to light yellow transparent oil. It is resistant to high and low temperatures, radiation, oxidation, and has good lubricity.

[0067] As a further preferred embodiment, the organosilicon modifier is at least one selected from dodecylphenyltrimethoxysilane, hexadecyltrimethoxysilane, polydimethylsiloxane, and hydroxyl-terminated polydimethylsiloxane.

[0068] Dodecylphenyltrimethoxysilane is an important organosilicon compound whose chemical properties are primarily determined by the phenyl and methoxysilane groups in its molecular structure. The benzene ring imparts hydrophobicity, making it useful in the preparation of hydrophobic coatings and waterproof materials.

[0069] Hexadecyltrimethoxysilane is a colorless to pale yellow transparent liquid. Its chemical properties are primarily determined by the long-chain alkyl (CH-) and methoxysilane groups (-Si(OCH)) in its molecular structure. The hexadecyl (CH-) group is a long-chain hydrophobic group. After being grafted onto the surface of magnesium hydroxide, the steric hindrance of the long-chain alkyl group prevents the aggregation of magnesium hydroxide particles and improves its dispersibility in the polymer matrix.

[0070] Polydimethylsiloxane appears as a colorless, transparent liquid or semi-solid (depending on its molecular weight). It is a hydrophobic silicone polymer with low surface energy, good flexibility, and thermal stability. Through physical adsorption or chemical bonding (such as reaction with the hydroxyl groups on the surface of magnesium hydroxide), it forms a uniform coating on the surface of magnesium hydroxide particles, significantly reducing the surface energy of the particles and reducing inter-particle agglomeration.

[0071] Hydroxy-terminated polydimethylsiloxane is an organosilicon polymer with hydroxyl (-OH) groups at both ends. These highly reactive hydroxyl groups (-OH) react with the hydroxyl groups (-OH) on the surface of magnesium hydroxide to form a stable Si-O-Mg chemical bond. The polydimethylsiloxane segments possess excellent hydrophobicity, and this hydrophobic surface makes magnesium hydroxide particles more easily dispersed in organic polymer matrices (such as polyethylene and polypropylene), improving the uniformity of the composite material.

[0072] Those skilled in the art will appreciate that magnesium hydroxide has a hydrophilic and oleophobic surface, large polarity, and is easily agglomerated, making its compatibility and dispersibility in polymer materials poor, directly causing the mechanical properties of the material to deteriorate severely, which greatly limits the scope of use of magnesium hydroxide flame retardants. In order to improve the compatibility and dispersibility of magnesium hydroxide and polymers, the surface properties of the "hydrophilic and oleophobic" surface are changed, and surface modification must be performed on magnesium hydroxide. The modified magnesium hydroxide is made hydrophobic, and by the modifier combination of the application, weak hydrophobic modifiers and hydrophobic modifiers are added in different steps, and the modified magnesium hydroxide achieves the optimal balance of flame retardant efficiency and mechanical properties, reaching unexpected effects.

[0073] Example 2

[0074] This embodiment provides a group of uses of the above-mentioned modifier combination in the preparation of a flame retardant.

[0075] As a further preferred embodiment, the flame retardant includes a magnesium hydroxide flame retardant.

[0076] As a further preferred embodiment, the application method of the modifier combination comprises the following steps:

[0077] (1) adding a weak hydrophobic modifier to a suspension containing 20-40% magnesium hydroxide for weak hydrophobic modification, the reaction temperature is 40-100° C., and the time is 3-5 hours; the weak hydrophobic modifier is combined with the surface hydroxyl group of the magnesium hydroxide through the hydrophilic group to complete the preliminary dispersion and surface weak hydrophobization, and the suspension after the reaction is dried for 12-24 hours at a temperature of 80-100° C. to obtain a preliminarily modified magnesium hydroxide powder;

[0078] (2) adding a medium-strong hydrophobic modifier to the magnesium hydroxide powder dried in step (1) for secondary modification, the reaction temperature is 25-45° C., and the reaction time is 1-3 hours. The strong hydrophobic modifier forms a stable coating layer on the surface of the activated magnesium hydroxide through long-chain hydrophobic groups, thereby reducing the surface energy and preventing agglomeration, and finally obtaining a magnesium hydroxide flame retardant with gradient distribution characteristics.

[0079] Example 3

[0080] This application describes a combination of modifiers for improving the performance of flame retardants. Where specific experimental procedures or conditions are not specified in the examples, they can be performed according to conventional experimental procedures or conditions described in literature in the field. Reagents or instruments used, where the manufacturer is not specified, are commercially available conventional reagents.

[0081] The present invention is further described in detail below with reference to specific examples. These examples should not be construed as limiting the scope of protection claimed in the present invention.

[0082] Experimental Group 1

[0083] A modifier combination for improving the application performance of a magnesium hydroxide flame retardant comprises 4 g of a weakly hydrophobic modifier, sodium butyrate, and 8 g of a strongly hydrophobic modifier, hydroxyl-terminated polydimethylsiloxane (OH-PDMS).

[0084] Experimental Group 2

[0085] A modifier combination for improving the application performance of a magnesium hydroxide flame retardant comprises 3g of a weakly hydrophobic modifier vinyl silane coupling agent and 3g of a strongly hydrophobic modifier dodecylphenyltrimethoxysilane.

[0086] Experimental Group 3

[0087] A modifier combination for improving the application performance of a magnesium hydroxide flame retardant comprises 4 g of a weakly hydrophobic modifier, aminopropyltriethoxysilane, and 2 g of a strongly hydrophobic modifier, fatty acid-modified silicone oil.

[0088] Experimental Group 4

[0089] A modifier combination for improving the application performance of a magnesium hydroxide flame retardant comprises 4 g of a weakly hydrophobic modifier, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, and 4.8 g of a strongly hydrophobic modifier, methyl silicone oil.

[0090] Comparative Example 1

[0091] Unmodified magnesium hydroxide.

[0092] Comparative Example 2

[0093] A composite modifier comprises 4 g of a coupling agent, 1.5 g of magnesium stearate, 1.5 g of calcium stearate, 2.5 g of fatty acid, 5.5 g of deionized water, 0.7 g of sodium oleate, 0.7 g of isopropyl alcohol and 0.3 g of acetic acid.

[0094] Comparative Example 3

[0095] A modifier comprises 2 g of aminopropyltriethoxysilane (a weakly hydrophobic modifier) ​​and 5 g of hydroxyl-terminated polydimethylsiloxane (a hydrophobic modifier).

[0096] Comparative Example 4

[0097] A modifier comprises 6 g of a weakly hydrophobic modifier, a vinyl silane coupling agent.

[0098] Comparative Example 5

[0099] A modifier comprises 6 g of a strongly hydrophobic modifier, dodecylphenyltrimethoxysilane.

[0100] Comparative Example 6

[0101] A modifier comprises 3 g of a weakly hydrophobic modifier vinyl silane coupling agent and 3 g of sodium butyrate.

[0102] Comparative Example 7

[0103] A modifier comprises 3 g of hydroxyl-terminated polydimethylsiloxane and 3 g of dodecylphenyltrimethoxysilane, both of which are strong hydrophobic modifiers.

[0104] Example 4 Performance Test

[0105] By modifying the magnesium hydroxide flame retardant with the modifier of the present application (such as hydroxyl-terminated polydimethylsiloxane, OH-PDMS), the dispersibility, compatibility, flame retardancy, and processing properties of the magnesium hydroxide are significantly improved. The following is a comparison of the performance data of the modified magnesium hydroxide flame retardant:

[0106] Table 1 Comparison of properties of modified magnesium hydroxide flame retardant

[0107]

[0108]

[0109] Example 5

[0110] Preparation method of magnesium hydroxide flame retardant 1:

[0111] 1) Adding 3 g of the weakly hydrophobic modifier vinyl silane coupling agent of Experimental Group 2 to a suspension containing 20% ​​magnesium hydroxide for weakly hydrophobic modification, reacting at 100° C. for 5 hours; and drying the modified suspension;

[0112] 2) The magnesium hydroxide powder dried in step 1) was added to 3 g of the strong hydrophobic modifier dodecylphenyltrimethoxysilane in experimental group 2, and the mixture was reacted at 45° C. for 3 hours to prepare magnesium hydroxide flame retardant 1.

[0113] Preparation method of magnesium hydroxide flame retardant 2:

[0114] The magnesium hydroxide was not subjected to any treatment to obtain magnesium hydroxide flame retardant 2.

[0115] Preparation method of magnesium hydroxide flame retardant 3:

[0116] The modifier ratio in Comparative Example 2 is adopted, comprising the following steps:

[0117] Step 1: 4 g of a coupling agent, 1.5 g of magnesium stearate, 1.5 g of calcium stearate, and 2.5 g of a fatty acid were placed in a homogenizer and stirred uniformly. The mixture was then poured into a sealable container. 5.5 g of deionized water was added to the container and stirred at 120 rpm for 13 minutes. The container was then sealed and allowed to stand at 3 degrees Celsius for 13 hours to obtain phase A.

[0118] Step 2: Add 0.7 g of sodium oleate and 0.7 g of isopropyl alcohol to phase A and stir evenly. Then, raise the temperature in the container to 60 degrees Celsius and keep warm for 2 hours. Remove the scum and impurities on the surface of the solution, pour the solution into a wide-mouth beaker, add 0.3 g of acetic acid to the beaker, stir at 80 rpm for 8 minutes, pour the stirred mixture into the beaker, and let it stand for 24 hours to obtain a composite modifier.

[0119] Step 3: Take an appropriate amount of magnesium hydroxide particles and add them to the stirring axe. Then, add the composite modifier to the stirring axe. The mass ratio of the added composite modifier to the magnesium hydroxide particles is 2:1. Turn on the stirring function of the stirring axe, stir the composite modifier and the magnesium hydroxide particles evenly for 40 minutes, control the temperature in the stirring axe to rise to 80 degrees Celsius, and keep warm for 4 hours to obtain magnesium hydroxide modified particles.

[0120] Step 4: After screening the vermiculite powder, diatomaceous earth powder and montmorillonite powder using a sieve, stir them evenly using a blender to obtain an inorganic mixture, add the charring accelerator, antioxidant, organosilsesquioxane and dicumyl peroxide into a blender, start the stirring function and stir them evenly to obtain an additive mixture;

[0121] Step 5: Add the magnesium hydroxide modified particles obtained in step 3 and the inorganic mixture obtained in step 4 to the stirring axe in sequence. After turning on the stirring axe and stirring for 13 minutes, add the additive mixture in step 4 to the stirring axe and continue stirring for 13 minutes. Then, heat the stirring axe to 50 degrees Celsius and keep it warm for 7 hours. Then turn off the heating function of the stirring axe and wait for it to cool to room temperature to obtain a modified hydroxide flame retardant.

[0122] Preparation method of magnesium hydroxide flame retardant 4:

[0123] The modifier ratio in Comparative Example 3 was adopted, and other conditions were the same as those in the method for preparing magnesium hydroxide flame retardant 1 to prepare magnesium hydroxide flame retardant 4.

[0124] Preparation method of magnesium hydroxide flame retardant 5:

[0125] The modifier ratio in Comparative Example 4 was adopted, and other conditions were the same as those in the method for preparing magnesium hydroxide flame retardant 1 to prepare magnesium hydroxide flame retardant 5.

[0126] Preparation method of magnesium hydroxide flame retardant 6:

[0127] The modifier ratio in Comparative Example 5 was adopted, and other conditions were the same as those in the method for preparing magnesium hydroxide flame retardant 1 to prepare magnesium hydroxide flame retardant 6.

[0128] Preparation method of magnesium hydroxide flame retardant 7:

[0129] The modifier ratio in Comparative Example 6 was adopted, and other conditions were the same as those in the method for preparing magnesium hydroxide flame retardant 1 to prepare magnesium hydroxide flame retardant 7.

[0130] Preparation method of magnesium hydroxide flame retardant 8:

[0131] The modifier ratio in Comparative Example 7 was adopted, and other conditions were the same as those in the method for preparing magnesium hydroxide flame retardant 1 to prepare magnesium hydroxide flame retardant 8.

[0132] Flame retardant performance test

[0133] Limiting Oxygen Index (LOI): The minimum oxygen concentration (volume percentage) required for a material to sustain combustion in a nitrogen-oxygen mixture. The higher the LOI value, the better the material's flame retardancy. Generally, materials with an LOI greater than 26% are considered flame retardant.

[0134] Magnesium hydroxide flame retardants 1, 2, 3, 4, 5, 6, 7, and 8 were correspondingly applied to flame retardant wires to form flame retardant wires 1, 2, 3, 4, 5, 6, 7, and 8, and LOI was tested.

[0135] Flame retardant wire 1LOI value: 36%;

[0136] Flame retardant wire 2LOI value: 17%;

[0137] Flame retardant wire 3LOI value: 33%;

[0138] Flame retardant wire 4LOI value: 34%;

[0139] Flame retardant wire 5LOI value: 24%;

[0140] Flame retardant wire 6LOI value: 33%;

[0141] Flame retardant wire 7LOI value: 25%;

[0142] Flame retardant wire 8LOI value: 33%;

[0143] Vertical Flame Test: In accordance with UL 94, the wire is fixed vertically on a flame test stand and ignited with a flame for 10 seconds. The burning time, dripping, and self-extinguishing behavior are observed and rated as V-0, V-1, or V-2.

[0144] Magnesium hydroxide flame retardants 1, 2, 3, 4, 5, 6, 7, and 8 were correspondingly applied to flame retardant wires to form flame retardant wires 1, 2, 3, 4, 5, 6, 7, and 8, and the flame retardant properties were tested.

[0145] Flame retardant wire 1: V-0;

[0146] Flame retardant wire 2: V-2;

[0147] Flame retardant wire 3: V-1;

[0148] Flame retardant wire 4: V-2;

[0149] Flame retardant wire 5: V-2;

[0150] Flame retardant wire 6: V-2;

[0151] Flame retardant wire 7: V-2.

[0152] Extrusion effect

[0153] Surface smoothness: Evaluate the surface smoothness of the wire sheath by visual inspection or touch. The wire is qualified if there are no obvious particles, bubbles or cracks.

[0154] Magnesium hydroxide flame retardants 1, 2, 3, 4, 5, 6, and 7 were correspondingly applied to flame retardant wires to form flame retardant wires 1, 2, 3, 4, 5, 6, and 7, and the extrusion effect was observed.

[0155] Flame retardant wire 1 effect: The surface of the wire is smooth and there is no hole inside.

[0156] Flame retardant wire 2 effect: The surface of the wire is rough and there are obvious particles inside.

[0157] Flame retardant wire 3 effect: The surface of the wire is relatively smooth and there are holes inside.

[0158] Flame retardant wire 4 effect: The surface of the wire is rough and there are bubbles inside.

[0159] Flame retardant wire 5 effect: The surface of the wire is rough and there are obvious particles inside.

[0160] Flame retardant wire 6 effect: The surface of the wire is rough and there are obvious particles inside.

[0161] Flame retardant wire 7 effect: The surface of the wire is rough and there are obvious particles inside.

[0162] Flame retardant wire 8 effect: The surface of the wire is rough and there are obvious particles inside.

[0163] The above description is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent replacements or improvements made within the spirit and principles of the present application should be included in the scope of protection of the present application.

Claims

1. A combination of modifiers for improving the application performance of flame retardants, characterized in that: The invention comprises a weak hydrophobic modifier and a strong hydrophobic modifier, wherein the mass ratio of the weak hydrophobic modifier to the strong hydrophobic modifier is 1:(0.5-2).

2. The modifier combination according to claim 1, characterized in that The weakly hydrophobic modifier combines with the hydroxyl groups on the surface of magnesium hydroxide through its hydrophilic group to achieve preliminary dispersion of the flame retardant and weak surface hydrophobization; The strong hydrophobic modifier forms a stable coating layer on the surface of the weakly hydrophobized magnesium hydroxide through long-chain hydrophobic groups, thereby reducing surface energy and preventing agglomeration; Through the independent action, sequential use and synergistic effect of the weak hydrophobic modifier and the strong hydrophobic modifier, the gradient distribution of the magnesium hydroxide flame retardant in the polymer matrix is ​​achieved, thereby improving the flame retardant efficiency and mechanical properties; Preferably, the number of carbon atoms of the weak hydrophobic modifier is ≤5, and the number of carbon atoms of the strong hydrophobic modifier is ≥8; Preferably, the weak hydrophobic modifier is selected from at least one of a surfactant or a silane coupling agent; and the strong hydrophobic modifier is selected from at least one of an organosilicon modifier or a silicone oil hydrophobic modifier.

3. The modifier combination according to claim 2, characterized in that The surfactant is selected from at least one of anionic surfactants and nonionic surfactants.

4. The modifier combination according to claim 3, characterized in that The surfactant is selected from at least one of sodium butyrate, sodium succinate, sodium propionate, sodium butyl sulfonate, polyoxyethylene fatty acid ester, sorbitan fatty acid ester, monoglycerol fatty acid ester, diglycerol fatty acid ester, and triglycerol fatty acid ester.

5. The modifier combination according to claim 2, characterized in that The silane coupling agent is selected from at least one of an aminosilane coupling agent or an epoxysilane coupling agent; Preferably, the aminosilane coupling agent comprises at least one amino functional group; Preferably, the epoxy silane coupling agent comprises at least one epoxy functional group.

6. The modifier combination according to claim 2, characterized in that The silicone oil hydrophobic modifier is selected from at least one of methyl silicone oil, ethyl silicone oil, toluene silicone oil, and fatty acid modified silicone oil.

7. The modifier combination according to claim 2, characterized in that The organosilicon modifier is selected from at least one of dodecylphenyltrimethoxysilane, hexadecyltrimethoxysilane, polydimethylsiloxane, and hydroxyl-terminated polydimethylsiloxane.

8. Use of a group of modifier combinations in the preparation of flame retardants, characterized in that: The invention comprises the modifier combination according to any one of claims 1 to 7.

9. The use according to claim 8, characterized in that The flame retardant includes a magnesium hydroxide flame retardant.

10. The use according to claim 8, characterized in that The application method of the modifier combination comprises the following steps: (1) adding a weak hydrophobic modifier to the magnesium hydroxide suspension for weak hydrophobic modification, wherein the weak hydrophobic modifier is combined with the surface hydroxyl group of the magnesium hydroxide through a hydrophilic group to complete preliminary dispersion and surface weak hydrophobization, and the modified suspension is dried; (2) A strong hydrophobic modifier is used to perform secondary modification on the magnesium hydroxide powder dried in step 1), wherein the strong hydrophobic modifier forms a stable coating layer on the surface of the weakly hydrophobized magnesium hydroxide through long-chain hydrophobic groups, thereby reducing the surface energy and preventing agglomeration, and finally obtaining a magnesium hydroxide flame retardant with gradient distribution characteristics.

Images