A halogen-free flame-retardant ABS alloy material and preparation method thereof

Abstract

The present invention discloses a halogen-free flame-retardant ABS alloy material and a preparation method thereof, and belongs to the field of polymer materials. The halogen-free flame-retardant ABS alloy material of the present invention comprises the following components in parts by weight: 75-90 parts of ABS resin, 13-20 parts of DIDOPO flame retardant, 10-20 parts of carbonizing agent, 2-5 parts of flame retardant synergist, 3-6 parts of compatibilizer, 0.2-0.7 parts of antioxidant, and 0.2-0.4 parts of lubricant. At the same time, a preparation method of the halogen-free flame-retardant ABS alloy material is disclosed. Under the premise of meeting the UL94 V0 2.0mm flame retardant performance, the halogen-free flame-retardant ABS alloy material of the present invention has a tensile strength of 43-46MPa and a cantilever beam notched impact strength of 15-27KJ / m 2 The halogen-free flame-retardant ABS alloy material of the present invention has excellent comprehensive performance, simple preparation process, and is suitable for application in the preparation of flame-retardant materials.

Description

Technical Field

[0001] The invention belongs to the field of polymer materials, and in particular relates to a halogen-free flame-retardant ABS alloy material and a preparation method thereof. Background Art

[0002] Among the flame retardants commonly used in ABS on the market, bromine antimony flame retardant is widely used, with a total addition of about 15-20%. The flame retardant is stable and the physical properties meet the use requirements. However, with the development of time, reducing and preventing the adverse effects of halogen flame retardants on the environment and human health has become an urgent problem that the polymer materials industry needs to solve. Halogen-free flame retardant polymers are favored because of their low toxicity and environmental protection, and have a wide range of application scenarios. Existing halogen-free flame retardant ABS usually achieves the purpose of flame retardancy by adding about 30-50% of inorganic metal compounds. There are differences in chemical properties and macroscopic physical forms between the inorganic metal compounds themselves and ABS, and they cannot be effectively compatible. There is a problem of poor compatibility between inorganic compounds and ABS. In addition, a large proportion of powder filling is prone to uneven dispersion in the ABS material, resulting in powder agglomeration, which becomes a stress concentration point, thereby deteriorating the material performance and causing the material to be easily brittle during the processing and molding process, making it difficult to meet the use requirements. Summary of the invention

[0003] The purpose of the present invention is to overcome the shortcomings of the prior art and provide a halogen-free flame-retardant ABS alloy material and a preparation method thereof.

[0004] To achieve the above purpose, the technical solution adopted by the present invention is: a halogen-free flame retardant ABS alloy material, comprising the following components in parts by weight: 75-90 parts of ABS resin, 13-20 parts of DIDOPO flame retardant, 10-20 parts of carbonizing agent, 2-5 parts of flame retardant synergist, 3-6 parts of compatibilizer, 0.2-0.7 parts of antioxidant, and 0.2-0.4 parts of lubricant.

[0005] ABS resin is a complex multiphase system, including three different phases of acrylonitrile, styrene and butadiene, including two extremely flammable phases of styrene and butadiene, and the combustion mechanisms of each phase are different, so it is difficult to achieve a flame retardant effect by adding a single flame retardant. The halogen-free flame retardant of ABS resin should be targeted. Its processing temperature is high, so that ordinary intumescent flame retardants cannot effectively match it with heat. Therefore, the present invention selects a flame retardant with high heat resistance, and achieves a good flame retardant effect through a "three-source-in-one" multi-component intumescent flame retardant. Since ABS resin does not contain oxygen, the acid generated by the acid source in the intumescent flame retardant has a poor dehydration esterification effect on it. Based on this, the present invention improves its flame retardant performance under an intumescent flame retardant by introducing oxygen elements into the main chain of the ABS resin molecule. The present invention also aims at the problem of poor carbonization of ABS, and by adding an efficient phosphorus-nitrogen flame retardant and a carbonizing agent for blending and modification, the mechanical properties of the material meet the use requirements under the premise of meeting the flame retardant requirements.

[0006] As a preferred embodiment of the present invention, the halogen-free flame retardant ABS alloy material includes the following components in parts by weight: 75-90 parts of ABS resin, 15-20 parts of DIDOPO flame retardant, 10-20 parts of carbonizing agent, 2-5 parts of flame retardant synergist, 4-6 parts of compatibilizer, 0.2-0.7 parts of antioxidant, and 0.2-0.4 parts of lubricant.

[0007] The inventors have found through research that DOPO flame retardants form a carbon layer at high temperatures, which has excellent heat insulation effect. In addition, phosphoric acid, metaphosphoric acid and polyphosphoric acid generated by thermal decomposition cover the surface of the polymer material, and together with the non-combustible gas generated by thermal decomposition, block the air, terminate the free radical chain reaction, and exert the synergistic effect of phosphorus and nitrogen.

[0008] As a preferred embodiment of the present invention, the ratio of the mass of the ABS resin to the sum of the mass of the DIDOPO flame retardant and the flame retardant synergist is: ABS resin: (DIDOPO flame retardant + flame retardant synergist) = (4-5):1.

[0009] The inventors have found through research that the present invention only needs to add 20% to 25% of the mass of ABS resin as flame retardant and synergistic flame retardant to achieve UL94 V0 2.0mm flame retardant performance. The small amount of addition overcomes the problem of incompatibility between powder and ABS resin in order to achieve flame retardant effect of traditional halogen-free flame retardant materials.

[0010] As a preferred embodiment of the present invention, the carbon-forming agent includes nylon 6 and / or polybutylene terephthalate.

[0011] The inventors have found through research that nylon 6 and / or polybutylene terephthalate as carbonizing agents reacting with some phosphazene compounds can increase the crosslinking degree of the matrix and thus increase the strength of the carbon layer.

[0012] As a preferred embodiment of the present invention, the flame retardant synergist includes zinc borate.

[0013] As a preferred embodiment of the present invention, the compatibilizer includes at least one of ethylene methyl acrylate copolymer, styrene grafted maleic anhydride and maleimide.

[0014] As a preferred embodiment of the present invention, the lubricant includes pentaerythritol stearate and / or ethylene bisstearamide.

[0015] As a preferred embodiment of the present invention, the antioxidant includes at least one of antioxidant 1010 , antioxidant 168 and antioxidant 1076 .

[0016] The present invention also provides a method for preparing any of the above-mentioned halogen-free flame-retardant ABS alloy materials, the method comprising the following steps:

[0017] (1) Weighing the components of the raw materials for preparing the ABS alloy material according to the weight ratio;

[0018] (2) fully mixing the components in step (1) to obtain a mixture;

[0019] (3) The mixed material is extruded and granulated through a twin-screw extruder, and injection molded to obtain a halogen-free flame-retardant ABS alloy material.

[0020] As a preferred embodiment of the present invention, in the step (3), the extrusion granulation conditions are 210-235°C, and the length-to-diameter ratio of the extruder screw is L / D=42:1.

[0021] Compared with the prior art, the present invention has the following beneficial effects:

[0022] (1) The DOPO flame retardant of the present invention forms a carbon layer at high temperature, so that the ABS alloy material has an excellent heat insulation effect.

[0023] (2) Part of the phosphazene compounds in the ABS alloy material of the present invention reacts with the carbon-forming agent to increase the crosslinking degree of the matrix, thereby increasing the strength of the carbon layer, and the material has good mechanical properties.

[0024] (3) Phosphoric acid, metaphosphoric acid and polyphosphoric acid generated by thermal decomposition of the ABS alloy material of the present invention cover the surface of the polymer material, and together with the non-flammable gas generated by thermal decomposition, block the air, terminate the free radical chain reaction, exert the synergistic effect of phosphorus and nitrogen, and achieve good flame retardant effect. DETAILED DESCRIPTION

[0025] In order to better illustrate the purpose, technical solutions and advantages of the present invention, the present invention will be further described below in conjunction with specific embodiments and comparative examples.

[0026] The raw material information used in the examples and comparative examples of the present invention is shown in Table 1.

[0027] Table 1 Raw material information of Examples 1-4 and Comparative Examples 1-6

[0028]

[0029] The phosphorus-containing flame retardant used in the present invention is homemade DI-DOPO, and the specific preparation method is: adding a dry tetrahydrofuran solution into a round-bottom flask protected by inert gas, adding a DOPO derivative and heating until the DOPO derivative is melted or completely dissolved, then dripping a trialkylamine into the flask through a peristaltic pump, keeping the solvent at a constant temperature and reflux for 1 hour, naturally cooling to room temperature, and then filtering the obtained precipitate, washing and drying to obtain a yellow powdery DI-DOPO.

[0030] Examples 1-5

[0031] Embodiments 1-5 of the present invention are respectively an embodiment of the halogen-free flame-retardant ABS alloy material of the present invention. The raw materials for preparing the material include the following components in parts by weight: 75-90 parts of ABS resin, 13-20 parts of DIDOPO flame retardant, 10-20 parts of carbonizing agent, 2-5 parts of flame retardant synergist, 3-6 parts of compatibilizer, 0.2-0.7 parts of antioxidant, and 0.2-0.4 parts of lubricant. The preparation method is: weigh ABS and carbonizing agent in proportion, put them into an oven at 100°C for baking for 2-3h, add them to a mixer, then weigh compatibilizer, antioxidant, and lubricant in proportion and add them thereto, stir for 3 minutes, add them to a twin-screw with a length-to-diameter ratio of L / D=42:1 for extrusion granulation, and the extrusion temperature is between 210-235°C to obtain finished particles, and then injection molding by an injection molding machine. The tensile strength of the alloy material was tested according to the standard test method of ISO 5272:2012; the Izod notched impact strength of the alloy material was tested according to the standard test method of ISO 180:2000; and the flame retardant performance of the alloy material was tested according to the standard test method of UL 94 2015. The specific ratios of the raw materials prepared in Examples 1-5 and the performance test results are shown in Table 2.

[0032] Comparative Examples 1-6

[0033] Comparative Examples 1-6 are materials prepared by lacking a certain component in the examples of the present invention. Except that the component types and proportions of the raw materials are different from those of Examples 1-5, the preparation and testing methods of the materials are the same as those of Examples 1-5. The proportions of the raw materials and the material performance test results of Comparative Examples 1-6 are shown in Table 2.

[0034] Table 2 Raw material composition and performance test results of Examples 1-5 and Comparative Examples 1-6

[0035]

[0036]

[0037] As can be seen from the above table, the halogen-free flame-retardant ABS alloy material of the present invention can achieve good mechanical properties (tensile strength above 40MPa, cantilever beam notch impact of 15KJ / m 2 Compared with other control group materials, the performance of Example 1 has good flame retardancy and the best mechanical properties. Compared with the selection of carbonizing agent, PA6 has less influence on the impact properties of the material.

[0038] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit the scope of protection of the present invention. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the essence and scope of the technical solution of the present invention.

Claims

1. A halogen-free flame-retardant ABS alloy material, characterized in that: The invention is composed of the following components in parts by weight: 75-90 parts of ABS resin, 15-20 parts of DIDOPO flame retardant, 10-20 parts of carbonizing agent, 2-5 parts of flame retardant synergist, 4-6 parts of compatibilizer, 0.2-0.7 parts of antioxidant, and 0.2-0.4 parts of lubricant; the carbonizing agent is nylon 6 and / or polybutylene terephthalate, and the flame retardant synergist is zinc borate; the preparation method of the DIDOPO flame retardant is: adding dry tetrahydrofuran solution to a round-bottom flask protected by inert gas, adding DOPO derivative and heating until the DOPO derivative is melted or completely dissolved, then dropping triallylamine into the flask through a peristaltic pump, keeping the solvent at a constant temperature and reflux for 1 hour, cooling naturally to room temperature, and then filtering the obtained precipitate, washing and drying to obtain yellow powdery DI-DOPO; The ratio of the mass of the ABS resin to the sum of the mass of the DIDOPO flame retardant and the flame retardant synergist is: ABS resin: (DIDOPO flame retardant + flame retardant synergist) = (4-5):

1.

2. The halogen-free flame-retardant ABS alloy material according to claim 1, characterized in that: The compatibilizer includes at least one of ethylene methyl acrylate copolymer, styrene grafted maleic anhydride and maleimide.

3. The halogen-free flame-retardant ABS alloy material according to claim 1, characterized in that: The lubricant includes pentaerythritol stearate and / or ethylene bisstearamide.

4. The halogen-free flame-retardant ABS alloy material according to claim 1, characterized in that: The antioxidant includes at least one of the antioxidant 1010 , the antioxidant 168 , and the antioxidant 1076 .

5. The method for preparing the halogen-free flame-retardant ABS alloy material according to any one of claims 1 to 4, characterized in that: The method comprises the following steps: (1) weighing the components of the raw materials for preparing the ABS alloy material according to the weight ratio; (2) fully mixing the components in step (1) to obtain a mixture; and (3) extruding and granulating the mixture, and injection molding the mixture to obtain a halogen-free flame-retardant ABS alloy material.

6. The preparation method according to claim 5, characterized in that: In the step (3), the extrusion granulation conditions are 210-235° C., and the length-to-diameter ratio of the extruder screw is L / D=42:1.

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