Polypropylene material with high flame retardant content and preparation method thereof

Abstract

The invention provides a polypropylene material with high flame retardant content. The polypropylene material is prepared from the following raw materials in parts by mass: 100-120 parts of polypropylene resin, 10-15 parts of modified flame-retardant polyacrylate resin, 30-40 parts of a ternary flame retardant, 0.5-1.5 parts of a light stabilizer, 0.1-1 part of an antioxidant and 0.1-1 part of a lubricant. The modified flame-retardant polyacrylate resin is added, so that the compatibility and dispersity of the components are effectively improved. On one hand, the modified flame-retardant polyacrylate resin has a polypropylene structure and can be interspersed and wound with a polypropylene resin molecular chain to form a complex and stable network structure, so that the compatibility between the modified flame-retardant polyacrylate resin and the polypropylene resin molecular chain is greatly enhanced; and on the other hand, the modified flame-retardant polyacrylate resin has a relatively large specific surface area, is rich in active groups such as hydroxyl and the like, and can be in full contact with the ternary flame retardant and generate interaction with the ternary flame retardant, so that the ternary flame retardant is more uniformly and stably distributed in the polypropylene resin.

Description

Technical Field

[0001] The invention relates to the technical field of polypropylene composite materials, and in particular to a polypropylene material with a high flame retardant content and a preparation method thereof. Background Art

[0002] In modern industrial production, polypropylene (PP) materials are widely used in many fields due to their good comprehensive properties, from daily necessities to industrial products. However, due to its flammable properties, there are great safety hazards in the event of a fire, which has led to the research of flame-retardant polypropylene materials receiving attention. As society pays more and more attention to fire safety, the demand for polypropylene materials with high flame retardancy is also growing.

[0003] In the development process of flame-retardant polypropylene materials, early research mainly focused on improving the flame retardant properties of materials by adding various flame retardants. Among them, bromine, phosphorus and silicon flame retardants are widely used. In practical applications, these flame retardants improve the flame retardant ability of materials to a certain extent, enabling the materials to meet basic fire protection requirements.

[0004] However, traditional flame-retardant polypropylene materials have exposed many defects in actual application. First, due to the uneven distribution of flame retardants inside the material, there are significant differences in the flame retardant effect of the material. For example, in some products, the flame retardant content in some areas is too high, while the flame retardant content in other areas is relatively low. This unevenness makes it impossible for the material to effectively play a flame retardant role as a whole when facing dangerous situations such as fire, and it is difficult to meet strict fire protection standards. Secondly, the uneven distribution of flame retardants also affects the service life of the material. During long-term use, the flame retardants in some areas are exhausted due to various factors, while the flame retardants in other areas fail to fully play their role. This not only reduces the overall performance of the material, but also increases 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 polypropylene material with a high flame retardant content, which not only adds a relatively high content of flame retardant, but also introduces a modified flame retardant polyacrylate resin. The modified flame retardant polyacrylate resin is a polypropylene resin grafted with glass fiber-iron oxide, which can effectively increase the compatibility and dispersibility of the components. On the one hand, the modified flame retardant polyacrylate resin has a polypropylene structure, which can intersperse and entangle with the molecular chains of the polypropylene resin to form a complex and stable network structure, greatly enhancing the compatibility between them; on the other hand, the modified flame retardant polyacrylate resin has a large specific surface area and is rich in active groups such as hydroxyl groups, which can fully contact and interact with the ternary flame retardant, firmly adsorb the ternary flame retardant on the surface, and then make it more evenly and stably distributed in the polypropylene resin. In addition, the modified flame-retardant polyacrylate resin itself has flame-retardant properties, and the grafted glass fiber-iron oxide can build a heat-insulating and oxygen-isolating barrier when the material burns, effectively curbing heat transfer and oxygen intrusion, thereby significantly delaying the combustion process, and working together with the bromine, phosphorus and silicon flame retardants in the ternary flame retardant to greatly improve the flame retardant effect. Through the above effects, the present invention achieves good flame retardant properties, and has excellent long-term flame retardant performance, and has good application prospects.

[0007] An object of the present invention is to provide a polypropylene material with a high flame retardant content, which is prepared from the following raw materials in parts by weight:

[0008]

[0009] in,

[0010] The modified flame-retardant polyacrylate resin is a polypropylene resin grafted with glass fiber-iron oxide;

[0011] The ternary flame retardant is a blend of a bromine flame retardant, a phosphorus flame retardant and a silicon flame retardant.

[0012] Furthermore, the mass ratio of the bromine flame retardant, the phosphorus flame retardant and the silicon flame retardant is 1:(0.5-1.5):(0.1-1).

[0013] Furthermore, the light stabilizer is selected from one or more of benzophenones, benzotriazoles, triazines, substituted acrylonitriles, and hindered amines.

[0014] Furthermore, the antioxidant is selected from one or more of antioxidant 1010 or antioxidant 168.

[0015] Furthermore, the lubricant is selected from one or more of ethylene wax, calcium stearate, stearic acid or amide wax.

[0016] Another object of the present invention is to provide a method for preparing the above-mentioned polypropylene material with a high flame retardant content, comprising the following steps:

[0017] S1, placing the hydroxylated glass fiber in a high-pressure reactor, then adding a solution of iron nitrate nonahydrate and urea thereto, heating for reaction, and calcining to obtain a glass fiber-iron oxide composite; and subjecting the glass fiber-iron oxide composite to plasma treatment to obtain a hydroxylated glass fiber-iron oxide composite;

[0018] S2, immersing the hydroxylated glass fiber-iron oxide composite in acrylic acid, heating and ultrasonicating to obtain an intermediate product; subjecting the intermediate product and acrylic acid ester to free radical polymerization under an inert gas atmosphere and a BPO catalyst to obtain a modified flame-retardant polyacrylate resin;

[0019] S3, the polypropylene resin, the modified flame retardant polyacrylate resin, the ternary flame retardant, the antioxidant and the lubricant are uniformly blended, then melted and blended by a twin-screw extruder, extruded and granulated, and dried to obtain a polypropylene material with a high flame retardant content.

[0020] Furthermore, in step S1, the mass ratio of the hydroxylated glass fiber to iron nitrate nonahydrate is 100:(0.1-1).

[0021] Furthermore, in step S1, the heating temperature is 100-120°C.

[0022] Furthermore, in step S2, the heating temperature is 60-80°C.

[0023] Furthermore, in step S3, the granulation temperature is 160-200°C.

[0024] The present invention has the following beneficial effects:

[0025] The present invention provides a polypropylene material with a high flame retardant content, which not only adds a relatively high content of flame retardant, but also introduces a modified flame retardant polyacrylate resin. The modified flame retardant polyacrylate resin is a polypropylene resin grafted with glass fiber-iron oxide, which can effectively increase the compatibility and dispersibility of the components. On the one hand, the modified flame retardant polyacrylate resin has a polypropylene structure, which can intersperse and entangle with the molecular chains of the polypropylene resin to form a complex and stable network structure, greatly enhancing the compatibility between them; on the other hand, the modified flame retardant polyacrylate resin has a large specific surface area and is rich in active groups such as hydroxyl groups, which can fully contact and interact with the ternary flame retardant, firmly adsorb the ternary flame retardant on the surface, and then make it more evenly and stably distributed in the polypropylene resin. In addition, the modified flame-retardant polyacrylate resin itself has flame-retardant properties, and the grafted glass fiber-iron oxide can build a heat-insulating and oxygen-isolating barrier when the material burns, effectively curbing heat transfer and oxygen intrusion, thereby significantly delaying the combustion process, and working together with the bromine, phosphorus and silicon flame retardants in the ternary flame retardant to greatly improve the flame retardant effect. Through the above effects, the present invention achieves good flame retardant properties, and has excellent long-term flame retardant performance, and has good application prospects. DETAILED DESCRIPTION

[0026] In order to more clearly illustrate the technical solution of the present invention, the following examples are listed. Unless otherwise stated, the raw materials, reactions and post-treatment methods shown in the examples are common raw materials on the market and technical methods well known to those skilled in the art.

[0027] The words "preferred", "preferably", "more preferably", etc. in the present invention refer to embodiments of the present invention that can provide certain beneficial effects in certain circumstances. However, other embodiments may also be preferred under the same circumstances or other circumstances. In addition, the description of one or more preferred embodiments does not imply that other embodiments are not applicable, nor is it intended to exclude other embodiments from the scope of the present invention.

[0028] It should be understood that, except in any operating examples, or where otherwise indicated, all numbers indicating, for example, the amounts of ingredients used in the specification and claims should be understood to be modified in all cases by the term "about". Therefore, unless indicated to the contrary, the numerical parameters set forth in the following specification and the appended claims are approximate values ​​that vary depending on the desired properties to be obtained by the present invention.

[0029] The present invention uses the following raw materials:

[0030] Polypropylene resin: Brand BX3800, purchased from SK Chemicals of South Korea.

[0031] Cage polysilsesquioxane: purchased from Xi'an Qiyue Biotechnology Co., Ltd.

[0032] Ternary flame retardant: triphenyl phosphate, decabromodiphenylethane and cage-type polysilsesquioxane (1:1:1, m / m / m).

[0033] Light stabilizer: Hindered amine light stabilizer UV3529.

[0034] Antioxidant: Antioxidant 1010.

[0035] Lubricant: Calcium stearate.

[0036] The preparation method of hydroxylated glass fiber comprises the following steps:

[0037] The glass fiber was immersed in a mixed solution of concentrated sulfuric acid and hydrogen peroxide (concentrated sulfuric acid: hydrogen peroxide = 7:3, v / v; the mass fraction of hydrogen peroxide was 30%) for 2 hours, and then washed and dried to obtain hydroxylated glass fiber.

[0038] The method for preparing an aqueous solution of iron nitrate nonahydrate and urea comprises the following steps:

[0039] 0.008 mol of ferric nitrate nonahydrate and 0.036 mol of urea were added into 60 ml of deionized water and stirred until dissolved to obtain an aqueous solution of ferric nitrate nonahydrate and urea.

[0040] Example 1

[0041] A polypropylene material with a high flame retardant content is prepared from the following raw materials in parts by weight:

[0042] Polypropylene resin 110 parts

[0043] Modified flame retardant polyacrylate resin 13 parts

[0044] 35 parts of ternary flame retardant

[0045] Light stabilizer 1 part

[0046] 0.5 parts of antioxidant

[0047] 0.5 parts of lubricant.

[0048] The method for preparing the polypropylene material with a high flame retardant content comprises the following steps:

[0049] S1. The hydroxylated glass fiber is placed in a high-pressure reactor, and then an aqueous solution of iron nitrate nonahydrate and urea is added thereto (the mass of iron nitrate nonahydrate is 1% of the mass of the hydroxylated glass fiber), reacted at 110° C. for 5 h, cooled, washed, dried, and then calcined at 380° C. for 1.5 h to obtain a glass fiber-iron oxide composite; the glass fiber-iron oxide composite is placed in a low-temperature plasma cleaning machine, and the plasma treatment time is set to 60 s, the power is set to 100 W, and the air flow rate is set to 400 ml / min, and plasma treatment is performed to obtain a hydroxylated glass fiber-iron oxide composite;

[0050] S2, immersing the hydroxylated glass fiber-iron oxide composite in acrylic acid, and ultrasonically reacting it at 80° C. for 10 hours to obtain an intermediate product; using water as a solvent, ultrasonically reacting the intermediate product and acrylate (intermediate product: acrylate=1:4, m / m) at 80° C. for 12 hours in a nitrogen atmosphere and a BPO catalyst (1% by mass of the reactants) to perform free radical polymerization to obtain a modified flame-retardant polyacrylate resin;

[0051] S3. According to the above mass fractions, the polypropylene resin, the modified flame-retardant polyacrylate resin, the ternary flame retardant, the antioxidant and the lubricant are uniformly blended, then melted and blended at 180-200°C by a twin-screw extruder, extruded and granulated, and dried to obtain a polypropylene material with a high flame retardant content.

[0052] Example 2

[0053] A polypropylene material with a high flame retardant content is prepared from the following raw materials in parts by weight:

[0054]

[0055] The preparation method of the polypropylene material with high flame retardant content is the same as that of Example 1.

[0056] Example 3

[0057] A polypropylene material with a high flame retardant content is prepared from the following raw materials in parts by weight:

[0058]

[0059] The preparation method of the polypropylene material with high flame retardant content is the same as that of Example 1.

[0060] Comparative Example 1

[0061] A polypropylene material with a high flame retardant content. The difference between this comparative example and Example 1 is that the modified flame retardant polyacrylate resin is replaced by polypropylene resin, and the remaining ingredients and preparation method are the same as those in Example 1.

[0062] Comparative Example 2

[0063] A polypropylene material with a high flame retardant content. The difference between this comparative example and Example 1 is that step S2-3 is not performed, and in step S4, the mass of the hydroxylated glass fiber-iron oxide composite is replaced by hydroxylated glass fiber, and the remaining ingredients and preparation method are the same as those in Example 1.

[0064] Test Case

[0065] The performance tests were conducted on the polypropylene materials with high flame retardant content prepared in Examples 1-3 and Comparative Examples 1-2.

[0066] Test method:

[0067] Flame retardancy: measured according to UL-94 standard.

[0068] Long-term flame retardancy: The polypropylene materials with high flame retardant content prepared in Examples 1-3 and Comparative Examples 1-2 were placed in an environment of 80° C. for 30 days, and their flame retardancy was tested again.

[0069] The test results are shown in Table 1.

[0070] Table 1 Performance test results

[0071]

[0072] According to Table 1, it can be seen that the components of the polypropylene material with high flame retardant content prepared in Examples 1-3 are well compatible with each other, the flame retardant is evenly distributed, and it shows good flame retardancy. After being placed at 80°C for 30 days, the flame retardancy does not change significantly. In Comparative Examples 1-2, the modified flame retardant polyacrylate resin is replaced with polypropylene resin and hydroxylated glass fiber without grafted iron oxide, respectively, and the flame retardancy and long-term flame retardancy of the prepared products are worse than those of the present invention. It can be seen from the above that the polypropylene material with high flame retardant content of the present invention has excellent performance and good application prospects.

[0073] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above and that the present invention can be implemented in other specific forms without departing from the spirit or essential features of the present invention. Therefore, the embodiments should be considered exemplary and non-restrictive in all respects, and the scope of the present invention is defined by the appended claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims be included in the present invention.

[0074] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. A polypropylene material with a high flame retardant content, characterized in that: It is prepared from the following raw materials in parts by weight: in, The modified flame-retardant polyacrylate resin is a polypropylene resin grafted with glass fiber-iron oxide; The ternary flame retardant is a blend of a bromine flame retardant, a phosphorus flame retardant and a silicon flame retardant.

2. The polypropylene material with a high flame retardant content according to claim 1, characterized in that: The mass ratio of the bromine flame retardant, the phosphorus flame retardant and the silicon flame retardant is 1:(0.5-1.5):(0.1-1).

3. The polypropylene material with a high flame retardant content according to claim 1, characterized in that: The light stabilizer is selected from one or more of benzophenones, benzotriazoles, triazines, substituted acrylonitriles, and hindered amines.

4. The polypropylene material with a high flame retardant content according to claim 1, characterized in that: The antioxidant is selected from one or more of the antioxidant 1010 or the antioxidant 168.

5. The polypropylene material with high flame retardant content according to claim 1, characterized in that: The lubricant is selected from one or more of ethylene wax, calcium stearate, stearic acid or amide wax.

6. The method for preparing the polypropylene material with high flame retardant content according to any one of claims 1 to 5, characterized in that: The steps include: S1, placing the hydroxylated glass fiber in a high-pressure reactor, then adding a solution of iron nitrate nonahydrate and urea thereto, heating for reaction, and calcining to obtain a glass fiber-iron oxide composite; and subjecting the glass fiber-iron oxide composite to plasma treatment to obtain a hydroxylated glass fiber-iron oxide composite; S2, immersing the hydroxylated glass fiber-iron oxide composite in acrylic acid, heating and ultrasonicating to obtain an intermediate product; subjecting the intermediate product and acrylic acid ester to free radical polymerization under an inert gas atmosphere and a BPO catalyst to obtain a modified flame-retardant polyacrylate resin; S3, the polypropylene resin, the modified flame retardant polyacrylate resin, the ternary flame retardant, the antioxidant and the lubricant are uniformly blended, then melted and blended by a twin-screw extruder, extruded and granulated, and dried to obtain a polypropylene material with a high flame retardant content.

7. The method for preparing a polypropylene material with a high flame retardant content according to claim 6, characterized in that: In step S1, the mass ratio of the hydroxylated glass fiber to iron nitrate nonahydrate is 100:(0.1-1).

8. The method for preparing a polypropylene material with a high flame retardant content according to claim 6, characterized in that: In step S1, the heating temperature is 100-120°C.

9. The method for preparing a polypropylene material with a high flame retardant content according to claim 6, characterized in that: In step S2, the heating temperature is 60-80°C.

10. The method for preparing a polypropylene material with a high flame retardant content according to claim 6, characterized in that: In step S3, the granulation temperature is 160-200°C.

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