A halogen-free flame-retardant nylon material and its preparation method

Abstract

The present invention relates to the technical field of flame-retardant nylon materials, and provides a halogen-free flame-retardant nylon material and a preparation method thereof, which comprise components in the following parts by mass: 80-120 parts of nylon, 30-40 parts of modified polyacrylate, 1-10 parts of modified nylon, 20-40 parts of halogen-free flame retardant, and 0.1-5 parts of auxiliary agent; the modified polyacrylate is a copolymer of phosphorus pentoxide, hydroxy acrylate, acrylic acid, acrylate, glass fiber and antimony trioxide; the modified nylon is a copolymer of nylon and acrylate. Among the components of the present invention, there is not only good affinity, and a uniform and stable mixed system can be formed. The introduced components can significantly improve the mechanical strength and flame retardant performance of the nylon composite material, endow the product with more excellent comprehensive performance, can also avoid harm to the environment and human body, has stronger ecological friendliness, solves the problems existing in the prior art, and is of great significance to the development and further popularization of nylon products.

Description

Technical Field

[0001] The present invention relates to the technical field of flame-retardant nylon materials, and particularly relates to a halogen-free flame-retardant nylon material and a preparation method thereof. Background Art

[0002] Nylon materials, namely polyamides (abbreviated as PA), are a kind of versatile high-molecular compounds. It has high melting point, excellent mechanical properties, strong heat resistance, good corrosion resistance and wear resistance. Therefore, nylon has been widely used in many fields such as the chemical industry, electronics and electrical engineering, and mechanical manufacturing. However, due to the flammable characteristics of nylon, there are great potential safety hazards in case of fire, which makes the research on flame-retardant nylon materials receive people's attention, and the demand for nylon materials with high flame-retardant performance is also increasing.

[0003] In the research and development process of flame-retardant nylon materials, the early focus was on using different types of flame-retardant additives to enhance the flame resistance of materials. Specifically, bromine-based, chlorine-based, and fluorine-based flame retardants have high flame-retardant efficiency and have been widely adopted. They effectively improve the flame-retardant level of materials in actual applications and ensure that the materials can meet the basic fire protection standards.

[0004] However, on the one hand, traditional flame retardants contain harmful substances such as halogens, so toxic gases and smoke will be released during use, which has a great potential for environmental pollution and does not conform to the current concept of energy conservation, emission reduction and environmental protection; on the other hand, due to the poor affinity between the flame retardant and the organic polymer, it is easy to be unevenly distributed inside the material, resulting in significant differences in the flame-retardant effects of different parts of the material, and it is impossible to effectively play the flame-retardant role as a whole, and it is difficult to meet the strict fire protection standards. In addition, the insufficient compatibility between multiple components also leads to the decline of the overall properties such as the strength, stability and service life of the material, and the flame-retardant performance of the polymer material toughened with glass fiber is often worse, because glass fiber has a "wick effect", similar to the wick of a candle, which can guide heat and combustibles to concentrate towards the fire source or high-temperature area, thus promoting combustion and further increasing the potential safety hazards.

[0005] In summary, it is necessary to develop a new technical solution to solve the problems existing in the prior art. Summary of the Invention

[0006] The present invention provides a halogen-free flame-retardant nylon material, which is prepared by compounding a modified polyacrylate, a modified nylon, a flame retardant and a nylon matrix resin. Not only do the components have good affinity with each other and can form a homogeneous and stable mixed system, but also the introduced components can significantly improve the mechanical strength and flame-retardant performance of the nylon composite material, endowing the product with more excellent comprehensive performance. The halogen-free flame retardant can also avoid harm to the environment and human body, and has stronger ecological friendliness. Therefore, the present invention solves the problems existing in the prior art and has important significance for the development and further popularization of nylon products.

[0007] An object of the present invention is to provide a halogen-free flame-retardant nylon material, which comprises components in the following parts by mass:

[0008] 80 - 120 parts of nylon

[0009] 30 - 40 parts of modified polyacrylate

[0010] 1 - 10 parts of modified nylon

[0011] 20 - 40 parts of halogen-free flame retardant

[0012] 0.1 - 5 parts of auxiliary agent;

[0013] Wherein,

[0014] The modified polyacrylate is a copolymer of phosphorus pentoxide, hydroxy acrylate, acrylic acid, acrylate, glass fiber and antimony trioxide;

[0015] The modified nylon is a copolymer of nylon and acrylate.

[0016] Further, the nylon is selected from one or more of nylon 6, nylon 66, nylon 1010 and nylon 610.

[0017] Further, the halogen-free flame retardant is selected from phosphate flame retardants or silicone flame retardants.

[0018] Further, the halogen-free flame retardant is preferably a phosphate flame retardant.

[0019] Further, the auxiliary agent is selected from one or more of antioxidants, lubricants, light stabilizers, odor inhibitors, toughening agents, crosslinking agents and initiators.

[0020] Another object of the present invention is to provide a preparation method of the above-mentioned halogen-free flame-retardant nylon material. The preparation method of the halogen-free flame-retardant nylon material comprises the following steps:

[0021] S1. Hydroxylate antimony trioxide and glass fiber, then add them into acrylic acid, and heat and react at 70 - 90 °C to obtain intermediate product 1;

[0022] S2. Mix phosphorus pentoxide and hydroxy acrylate, and heat and react at 60 - 90 °C to obtain intermediate product 2;

[0023] S3. Mix the intermediate product 1, intermediate product 2, acrylate and catalyst, and heat and stir to react at 60 - 90 °C in an inert gas atmosphere to obtain modified polyacrylate;

[0024] S4. Mix nylon, acrylate and initiator, and heat and stir to react at 60 - 90 °C to obtain modified nylon;

[0025] S5. Mix the modified polyacrylate, modified nylon, nylon, halogen - free flame retardant and additives, add them into an extruder, and melt - extrude and pelletize to obtain a halogen - free flame - retardant nylon material.

[0026] Further, in step S1, the mass ratio of antimony trioxide to glass fiber is 1:(1 - 3).

[0027] Further, in step S2, the molar ratio of phosphorus pentoxide to hydroxy acrylate is 1:(1.5 - 3).

[0028] Further, in step S3, the mass ratio of intermediate product 1, intermediate product 2 and acrylate is (4 - 8):(1 - 5):(1 - 3).

[0029] Further, in step S4, the mass ratio of nylon to acrylate is 1:(4 - 8).

[0030] The present invention has the following beneficial effects:

[0031] The present invention provides a halogen - free flame - retardant nylon material, which is compounded with components such as nylon, modified polyacrylate, modified nylon and halogen - free flame retardant. Among them, the modified polyacrylate first grafts a mixture of hydroxylated antimony trioxide and glass fiber with acrylic acid to obtain intermediate product 1, and reacts phosphorus pentoxide with hydroxy acrylate to obtain intermediate product 2 with a phosphate ester structure. Then, the intermediate product 1 with double bonds, intermediate product 2 and acrylate monomer are subjected to free - radical polymerization to obtain modified polyacrylate. This component not only has flame - retardant antimony trioxide and phosphate ester groups, but also introduces glass fiber, which can improve the strength of the composite material. At the same time, since the flame - retardant material is connected to the glass fiber through chemical bonds, the situation that combustibles are conducted through the glass fiber is avoided, effectively reducing the possibility of combustion support. In addition, the modified polyacrylate has excellent affinity with phosphate - based flame retardants, which helps to promote the uniform dispersion and combination of the halogen - free flame retardant in the mixed system, so as to maximize the function of the flame retardant and meet various strict and extreme fire - prevention requirements.

[0032] The modified nylon of the present invention is obtained by copolymerizing acrylate and nylon. Macromolecules of polyacrylate are grafted onto the nylon material, thereby playing the role of a compatibilizer. After being melt-mixed with components such as nylon, modified polyacrylate, and additives, it can enhance the compatibility between different substances, further enhance the bonding strength of nylon, modified polyacrylate, and flame retardant, and ensure the reliability of the mechanical properties, flame retardant properties, stability, durability, and other aspects of the product. Detailed Embodiment

[0033] To more clearly illustrate the technical solution of the present invention, the following examples are listed. The raw materials, reactions, and post-treatment means appearing in the examples are all common raw materials on the market and technical means well-known to those skilled in the art, unless otherwise specified.

[0034] The terms "preferred", "preferably", "more preferably", etc. in the present invention refer to embodiments of the present invention that can provide certain beneficial effects in certain cases. However, in the same or other cases, other embodiments may also be preferred. In addition, the description of one or more preferred embodiments does not imply that other embodiments are not available, nor is it intended to exclude other embodiments from the scope of the present invention.

[0035] It should be understood that, unless otherwise indicated in any operating example or otherwise, all numbers representing the amounts of ingredients used in the specification and claims, should be understood to be modified in all instances by the term "about". Accordingly, unless indicated to the contrary, the numerical parameters set forth in the following specification and attached claims are approximations that vary depending upon the desired properties sought to be obtained by the present invention.

[0036] The following raw materials are used in the embodiments of the present invention:

[0037] Nylon: Nylon 66.

[0038] Glass fiber: Chopped glass fiber, purchased from Tai'an Senyang Composite Materials Co., Ltd.

[0039] Halogen-free flame retardant: Triphenyl phosphate.

[0040] Additive: A light stabilizer UV-3529, antioxidant 1010, lubricant calcium stearate, and initiator DTBP with a mass ratio of 1:1:1:1.

[0041] Example 1

[0042] A halogen-free flame-retardant nylon material is prepared from the following raw materials in parts by mass:

[0043] Nylon 80 parts

[0044] Modified polyacrylate 30 parts

[0045] 3 parts of modified nylon

[0046] 25 parts of halogen-free flame retardant

[0047] 2 parts of additives;

[0048] The preparation method of the above-mentioned halogen-free flame-retardant nylon material comprises the following steps:

[0049] S1. Soak Sb 2 O 3 powder (average particle size 30 μm) and glass fiber in 5 mol / L sodium hydroxide solution, ultrasonically treat for 3 h, then wash until neutral, dry and mix with glucose (Sb 2 O 3 :glucose = 1:10, m / m) for ball milling (ball-to-material ratio 5:1). After washing and drying, soak the product in acrylic acid, ultrasonically react at 80 °C for 10 h, filter, wash and dry to obtain intermediate product 1;

[0050] S2. Mix phosphorus pentoxide and hydroxypropyl methacrylate in a molar ratio of 1:2, react at 75 °C for 3 h, then add 4 wt% of water to the system for hydrolysis, and keep warm at 90 °C for 2 h to obtain intermediate product 2;

[0051] S3. Using water as a solvent, mix the intermediate product 1, intermediate product 2 and methyl methacrylate in a mass ratio of 6:3:1, stir and react at 80 °C for 12 h under a nitrogen atmosphere and in the presence of a BPO catalyst (1% of the reactant mass), filter, wash and dry to obtain modified polyacrylate;

[0052] S4. Using a solvent of water and isopropanol in a volume ratio of 4:1, mix nylon and methyl methacrylate in a mass ratio of 1:5, use copper nitrate (1% of the reactant mass) and DMA (5% of the reactant mass) as an initiator system, stir and react at 70 °C for 4 h, filter, wash and dry to obtain modified nylon;

[0053] S5. According to the above mass parts, uniformly mix the modified polyacrylate, modified nylon, nylon, halogen-free flame retardant and additives, add them to a twin-screw extruder and melt-extrude and pelletize at 230 °C to obtain a halogen-free flame-retardant nylon material.

[0054] Example 2

[0055] A halogen-free flame-retardant nylon material is prepared from raw materials with the following mass parts:

[0056] 100 parts of nylon

[0057] 35 parts of modified polyacrylate

[0058] 4 parts of modified nylon

[0059] 30 parts of halogen-free flame retardant

[0060] 2.5 parts of additives;

[0061] The preparation method of the above-mentioned halogen-free flame-retardant nylon material comprises the following steps:

[0062] S1. Immerse Sb 2 O 3 powder (average particle size 30 μm) and glass fiber in 5 mol / L sodium hydroxide solution, ultrasonically treat for 3 h, then wash until neutral, dry and mix with glucose (Sb 2 O 3 : glucose = 1:10, m / m) for ball milling treatment (ball-to-material ratio 5:1), after washing and drying, immerse the product in acrylic acid, and carry out ultrasonic reaction at 80°C for 10 h, filter, wash and dry to obtain intermediate product 1;

[0063] S2. Mix phosphorus pentoxide and hydroxypropyl methacrylate in a molar ratio of 1:2, react at 75°C for 3 h, then add 4 wt% of water to the system for hydrolysis, and keep warm at 90°C for 2 h to obtain intermediate product 2;

[0064] S3. Using water as a solvent, mix the intermediate product 1, intermediate product 2 and methyl methacrylate in a mass ratio of 6:3:1, and carry out stirring reaction at 80°C for 12 h under a nitrogen atmosphere and BPO catalyst (1% of the reactant mass), filter, wash and dry to obtain modified polyacrylate;

[0065] S4. Using water and isopropanol with a volume ratio of 4:1 as solvents, mix nylon and methyl methacrylate in a mass ratio of 1:5, and use copper nitrate (1% of the reactant mass) and DMA (5% of the reactant mass) as an initiator system, carry out stirring reaction at 70°C for 4 h, filter, wash and dry to obtain modified nylon;

[0066] S5. According to the above mass parts, uniformly mix the modified polyacrylate, modified nylon, nylon, halogen-free flame retardant and additives, and add them to a twin-screw extruder for melt extrusion granulation at 230°C to obtain a halogen-free flame-retardant nylon material.

[0067] Example 3

[0068] A halogen-free flame-retardant nylon material is prepared from raw materials with the following mass parts:

[0069] 120 parts of nylon

[0070] 40 parts of modified polyacrylate

[0071] 5 parts of modified nylon

[0072] 35 parts of halogen-free flame retardant

[0073] 3 parts of auxiliary agent;

[0074] The preparation method of the above-mentioned halogen-free flame-retardant nylon material comprises the following steps:

[0075] S1. Soak Sb 2 O 3 powder (average particle size 30 μm) and glass fiber in 5 mol / L sodium hydroxide solution, ultrasonically treat for 3 h, then wash until neutral, dry and mix with glucose (Sb 2 O 3 : glucose = 1:10, m / m) for ball milling treatment (ball-to-material ratio 5:1), after washing and drying, soak the product in acrylic acid, ultrasonically react at 80 °C for 10 h, filter, wash and dry to obtain intermediate product 1;

[0076] S2. Mix phosphorus pentoxide and hydroxypropyl methacrylate in a molar ratio of 1:2, react at 75 °C for 3 h, then add 4 wt% of water to the system for hydrolysis, and keep warm at 90 °C for 2 h to obtain intermediate product 2;

[0077] S3. Using water as a solvent, mix the intermediate product 1, intermediate product 2 and methyl methacrylate in a mass ratio of 6:3:1, stir and react at 80 °C for 12 h under a nitrogen atmosphere and in the presence of a BPO catalyst (1% of the reactant mass), filter, wash and dry to obtain a modified polyacrylate;

[0078] S4. Using water and isopropanol in a volume ratio of 4:1 as a solvent, mix nylon and methyl methacrylate in a mass ratio of 1:5, use copper nitrate (1% of the reactant mass) and DMA (5% of the reactant mass) as an initiator system, stir and react at 70 °C for 4 h, filter, wash and dry to obtain modified nylon;

[0079] S5. According to the above mass parts, mix the modified polyacrylate, modified nylon, nylon, halogen-free flame retardant and auxiliary agent evenly, add them to a twin-screw extruder and melt-extrude and pelletize at 230 °C to obtain a halogen-free flame-retardant nylon material.

[0080] Comparative Example 1

[0081] A halogen-free flame-retardant nylon material. The difference between this comparative example and Example 1 is that step S1 is deleted, and intermediate product 1 is replaced with a mixture of Sb 2 O 3 and glass fiber in a mass ratio of 1:2, and the other components and preparation method are the same as those in Example 1.

[0082] Comparative Example 2

[0083] A halogen-free flame-retardant nylon material. The difference between this comparative example and Example 1 is that step S2 is deleted. In step S3, intermediate product 2 is not added, and the remaining components and preparation method are the same as those in Example 1.

[0084] Comparative Example 3

[0085] A halogen-free flame-retardant nylon material. The difference between this comparative example and Example 1 is that step S4 is deleted and modified nylon is not added, and the remaining components and preparation method are the same as those in Example 1.

[0086] Test Example

[0087] Perform performance tests on the halogen-free flame-retardant nylon materials prepared in Examples 1-3 and Comparative Examples 1-3.

[0088] Test method:

[0089] Determine the tensile strength, flexural strength, and flame retardancy according to standards such as ISO 527, ISO 178, and UL-94.

[0090] The test results are shown in Table 1.

[0091] Table 1 Performance test results

[0092]

[0093] It can be seen from Table 1 that the compatibility of various components in the halogen-free flame-retardant nylon materials prepared in Examples 1-3 is good. The glass fiber, Sb 2 O 3 and phosphate ester in the modified polyacrylate can exert their functions to the greatest extent. Under the compatibilizing effect of the modified nylon, the binding effect with nylon and the halogen-free flame retardant is further improved, achieving synergistic enhancement and having excellent comprehensive properties. While in Comparative Examples 1-3, the modified polyacrylate or modified nylon component is replaced, reducing the affinity between different substances, and the stability, uniformity, and binding degree of the mixed system are reduced, resulting in less than ideal mechanical strength and flame retardancy of the samples. In summary, the halogen-free flame-retardant nylon material of the present invention has excellent performance, overcomes the defects existing in the prior art, and has good application prospects.

[0094] For those skilled in the art, it is obvious that the present invention is not limited to the details of the above-described exemplary embodiments, and can be implemented in other specific forms without departing from the spirit or basic characteristics of the present invention. Therefore, in any aspect, the embodiments should be regarded as exemplary and non-limiting. The scope of the present invention is defined by the appended claims rather than the above description. Therefore, it is intended to embrace all changes falling within the meaning and scope of the equivalent elements of the claims within the present invention.

[0095] In addition, it should be understood that although this specification is described according to embodiments, not every embodiment only includes an independent technical solution. This narrative manner of the specification is only for clarity. Those skilled in the art should regard the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A halogen-free flame-retardant nylon material, characterized in that: The halogen-free flame-retardant nylon material comprises the following components in parts by mass: Nylon 80-120 parts Modified polyacrylate 30-40 parts Modified nylon 1-10 parts Halogen-free flame retardant 20-40 parts Additives 0.1-5 parts; in, The modified polyacrylate is a copolymer of phosphorus pentoxide, hydroxy acrylate, acrylic acid, acrylate, glass fiber and antimony trioxide; The modified nylon is a copolymer of nylon and acrylate; The preparation method of the halogen-free flame-retardant nylon material comprises the following steps: S1, hydroxylating antimony trioxide and glass fiber, then adding them into acrylic acid, heating at 70-90°C for reaction, and obtaining intermediate product 1; S2, mixing phosphorus pentoxide and hydroxy acrylate, heating at 60-90° C. for reaction, to obtain intermediate product 2; S3, mixing the intermediate product 1, the intermediate product 2, the acrylic ester and the catalyst, heating and stirring at 60-90° C. under an inert gas atmosphere to react, to obtain a modified polyacrylate; S4, mixing nylon, acrylate and initiator, heating and stirring at 60-90°C to react, thereby obtaining modified nylon; S5. Mix the modified polyacrylate, modified nylon, nylon, halogen-free flame retardant and additives, add them into an extruder, melt-extrude and granulate to obtain a halogen-free flame retardant nylon material.

2. The halogen-free flame-retardant nylon material according to claim 1, characterized in that: The nylon is selected from one or more of nylon 6, nylon 66, nylon 1010 and nylon 610.

3. The halogen-free flame-retardant nylon material according to claim 1, characterized in that: The halogen-free flame retardant is selected from phosphate flame retardants or organosilicon flame retardants.

4. The halogen-free flame-retardant nylon material according to claim 1, characterized in that: The auxiliary agent is selected from one or more of an antioxidant, a lubricant, a light stabilizer, an odor inhibitor, a toughening agent, a crosslinking agent, and an initiator.

5. The halogen-free flame-retardant nylon material according to claim 1, characterized in that: In step S1, the mass ratio of antimony trioxide to glass fiber is 1:(1-3).

6. The halogen-free flame-retardant nylon material according to claim 1, characterized in that: In step S2, the molar ratio of phosphorus pentoxide to hydroxy acrylate is 1:(1.5-3).

7. The halogen-free flame-retardant nylon material according to claim 1, characterized in that: In step S3, the mass ratio of the intermediate product 1, the intermediate product 2 and the acrylic ester is (4-8):(1-5):(1-3).

8. The halogen-free flame-retardant nylon material according to claim 1, characterized in that: In step S4, the mass ratio of nylon to acrylate is 1:(4-8).

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