ABS (Acrylonitrile Butadiene Styrene) composite material with good flame retardance and preparation method thereof

Abstract

The invention relates to the technical field of flame-retardant ABS (Acrylonitrile Butadiene Styrene) materials, in particular to an ABS composite material with good flame retardance and a preparation method thereof. The ABS composite material disclosed by the invention is prepared from the following raw materials in parts by weight: 80 to 100 parts of ABS, 15 to 18 parts of tetrabromobisphenol A, 3 to 5 parts of a synergistic flame retardant and 0.1 to 0.5 part of an antioxidant, the synergistic flame retardant is obtained by grafting ferroferric oxide on the surface of expandable graphite and then coating phytic acid; the ABS composite material disclosed by the invention has excellent flame-retardant capability and also has relatively good tensile strength and impact strength, and the problem that the mechanical strength of a traditional flame-retardant ASB material is greatly reduced due to the addition of a flame retardant is avoided.

Description

Technical Field

[0001] The present invention relates to the technical field of flame-retardant ABS materials, and particularly relates to a flame-retardant ABS composite material with good flame-retardant performance and a preparation method thereof. Background Art

[0002] Acrylonitrile-butadiene-styrene resin (ABS) is a widely used high molecular polyester resin. ABS has good fatigue resistance, relatively good heat resistance, excellent dimensional stability and other advantages. However, in some specific application fields (such as materials for communication heat dissipation components), high requirements are placed on the flame-retardant performance of ABS, which limits the application of ABS composite materials in some specific fields.

[0003] Patent technical literature CN115044161A discloses a flame-retardant ABS material, a preparation method and an application thereof. The flame-retardant ABS material of this invention comprises the following components in parts by weight: 74 - 84.5 parts of ABS resin, 12 - 17 parts of phosphoric acid flame retardant, 3 - 7 parts of auxiliary flame retardant, 0.2 - 1 part of processing aid, 0.2 - 1 part of amide lubricant containing carboxylate group; by adding a properly proportioned compounded phosphoric acid flame retardant and a 1,3,5-triazine compound synergistic flame retardant into an ABS resin with an appropriate rubber content, the addition amount of the flame retardant can be effectively reduced, and by adding an amide lubricant containing carboxylate group, the flame-retardant stability of the flame-retardant system is improved. The obtained flame-retardant ABS material has high flame-retardant efficiency and reaches the halogen-free V-0 grade. However, with the addition of the flame retardant, the mechanical properties of the ABS composite material will inevitably be damaged to a certain extent. Summary of the Invention

[0004] In view of this, the purpose of the present invention is to provide a flame-retardant ABS composite material with good flame-retardant performance and a preparation method thereof, so as to solve the problems of limited flame-retardant performance and mechanical properties of ABS materials in the prior art.

[0005] Based on the above purpose, the present invention provides a flame-retardant ABS composite material, comprising the following raw materials in parts by weight: 80 - 100 parts of ABS, 15 - 18 parts of tetrabromobisphenol A, 3 - 5 parts of synergistic flame retardant, 0.1 - 0.5 part of antioxidant; The preparation steps of the synergistic flame retardant are as follows: S1: Mix ferric tetroxide, hydrogen peroxide, absolute ethanol and deionized water, react at 80 - 100 °C for 8 - 10 h, filter, wash and dry to obtain hydroxylated ferric tetroxide; S2: Mix hydroxylated ferric tetroxide, silane coupling agent KH550, absolute ethanol and deionized water, react at 80 - 100 °C for 8 - 10 h, filter, wash and dry at 70 - 90 °C to obtain aminated ferric tetroxide; S3: Disperse expandable graphite in distilled water, add EDC and NHS, ultrasonically disperse, then add amino-functionalized iron oxide, ultrasonically mix evenly, mechanically stir at 80 - 90 °C for 1 - 2 h, perform magnetic separation, wash, and dry to obtain functionalized expandable graphite; S4: Disperse the functionalized expandable graphite in a mixed solution, then add phytic acid and KH-550, react at 60 - 65 °C for 10 - 12 h. After the reaction ends, repeatedly filter the product, wash with ethanol and then centrifuge, and finally dry to constant weight to obtain a synergistic flame retardant; In step S1, the weight ratio of the iron oxide, hydrogen peroxide, absolute ethanol, and deionized water is 3 - 4 g: 5 - 6 g: 6 - 8 g: 11 - 13 g; In step S2, the weight ratio of the hydroxylated iron oxide, silane coupling agent KH550, absolute ethanol, and deionized water is 2.8 - 3.2 g: 1 - 1.2 g: 3.6 - 4.2 g: 6 - 8 g; In step S3, the weight ratio of the expandable graphite, distilled water, EDC, NHS, and amino-functionalized iron oxide is 2.5 - 3 g: 200 - 400 mL: 2.1 - 2.3 g: 1.5 - 2 g: 2.5 - 3 g; In step S4, the weight ratio of the functionalized expandable graphite, mixed solution, phytic acid, and KH-550 is 5 - 6 g: 100 - 150 mL: 2.5 - 3 mL: 0.25 - 0.4 g.

[0006] Preferably, the iron oxide in step S1 is self-made, and the specific preparation steps are as follows: Mix ferric nitrate, ferrous chloride, ammonia water, absolute ethanol, and deionized water, react at 70 - 90 °C for 10 - 16 h, filter, wash, and dry to obtain iron oxide.

[0007] Preferably, the weight ratio of the ferric nitrate, ferrous chloride, ammonia water, absolute ethanol, and deionized water is 3 - 4 g: 1.2 - 1.8 g: 3 - 4 g: 3 - 4 g: 7 - 9 g.

[0008] Preferably, the particle size of the expandable graphite in step S3 is 150 - 200 μm.

[0009] Preferably, the mixed solution in step S4 is composed of ethanol and deionized water mixed in a volume ratio of 1:1.

[0010] Preferably, the ABS is purchased from Daqing Petrochemical, with the model 750A.

[0011] Preferably, the antioxidant is one of antioxidant Irganox168, antioxidant Irganox1010, and antioxidant Irganox1330.

[0012] More preferably, the antioxidants are all sourced from BASF Corporation.

[0013] Furthermore, the present invention also provides a method for preparing an ABS composite material with good flame retardancy, comprising the following steps: weighing ABS, tetrabromobisphenol A, a synergistic flame retardant, and an antioxidant according to the weight parts of the raw materials, mixing and stirring evenly to obtain a mixture, and extruding and pelletizing from an extruder to obtain an ABS composite material with good flame retardancy.

[0014] Preferably, the extruder is a twin-screw extruder.

[0015] Preferably, the twin-screw extruder comprises six temperature zones arranged in sequence, namely, the temperature of zone 1 is 180 - 210 °C, the temperature of zone 2 is 200 - 230 °C, the temperature of zone 3 is 200 - 230 °C, the temperature of zone 4 is 200 - 230 °C, the temperature of zone 5 is 200 - 230 °C, and the temperature of zone 6 is 200 - 230 °C.

[0016] Preferably, the head temperature of the twin-screw extruder is 200 - 230 °C, and the screw speed is 200 - 280 r / min.

[0017] Advantages of the present invention: The ABS composite material of the present invention has excellent flame retardancy ability, good tensile strength and impact strength, avoiding the problem that the mechanical strength of traditional flame-retardant ASB materials is greatly reduced due to the addition of flame retardants.

[0018] By grafting iron oxide and phytic acid onto the surface of expandable graphite, the expandable graphite can provide an expanding flame-retardant framework, and both iron oxide and phytic acid have certain flame-retardant abilities, so that the flame retardancy and mechanical strength of the ABS composite material are improved to a certain extent.

[0019] By first grafting iron oxide onto the surface of expandable graphite and then using it as a "nano-bridge", the connection between phytic acid and expandable graphite is realized, so that phytic acid is coated on the surface of expandable graphite to form a synergistic flame retardant, and the flame retardancy and mechanical properties of the ABS composite material are maintained at a relatively excellent level.

[0020] The synergistic flame retardant of the present invention improves the compatibility between the synergistic flame retardant and the matrix compared with directly mixing expandable graphite, iron oxide and phytic acid as a flame retardant and adding it directly. Specific Embodiments

[0021] To make the objectives, technical solutions and advantages of the present invention clearer, the following further elaborates on the present invention with specific embodiments.

[0022] The sources or properties of the raw materials in the examples and comparative examples of the present invention are as follows: Iron nitrate, Shandong Xuxiang Chemical Co., Ltd.; Ferrous chloride, Henan Anno Chemical Technology Co., Ltd.; Ammonia water, Jinan Junfeng Chemical Co., Ltd.; Hydrogen peroxide, Jinan Qiangsheng Chemical Co., Ltd.; Tetrabromobisphenol A, Shanghai Hongzhuang Chemical Technology Co., Ltd.; Antioxidants (models Irganox168, Irganox1010, Irganox1330), BASF The zone temperatures of the twin-screw extruder are 180 °C in zone 1, 200 °C in zone 2, 210 °C in zone 3, 220 °C in zone 4, 230 °C in zone 5, and 230 °C in zone 6 in sequence.

[0023] Example 1: A flame-retardant ABS composite material, and the specific preparation steps are as follows: (1) Mix 3 g of iron nitrate, 1.2 g of ferrous chloride, 3 g of ammonia water, 3 g of absolute ethanol, and 7 g of deionized water, react in a reaction vessel at 70 °C for 10 h, cool to room temperature, filter, wash the product, and dry it at 60 °C for 6 h to obtain magnetite; Place 3 g of magnetite, 5 g of hydrogen peroxide, 6 g of absolute ethanol, and 11 g of deionized water in a reaction vessel together, react at 80 °C for 8 h, filter, wash, and dry the product at 70 °C for 6 h to obtain hydroxylated magnetite; (2) Mix 2.8 g of hydroxylated magnetite, 1 g of silane coupling agent KH550, 3.6 g of absolute ethanol, and 6 g of deionized water, react in a reaction vessel at 80 °C for 8 h, filter, wash, and dry at 70 °C for 6 h to obtain amino-functionalized magnetite; (3) Take 2.5 g of expandable graphite and ultrasonically disperse it in 200 mL of distilled water. Add 2.1 g of EDC and 1.5 g of NHS to the dispersion, mechanically stir for 30 min, then add 2.5 g of amino-functionalized magnetite, ultrasonically disperse for 30 min, mechanically stir the mixed solution at 80 °C for 1 h, perform magnetic separation, wash, and dry the product at 60 °C for 24 h to obtain functionalized expandable graphite; (4) Place 5 g of functionalized expandable graphite in a three-necked flask, add 100 mL of a mixed solution (ethanol:deionized water is 1:1). Subsequently, mix 2.5 mL of phytic acid and 0.25 g of KH-550 in a beaker, add the mixture evenly to the above mixed solution, and stir evenly at 60 °C for 10 h. After the reaction ends, filter the product repeatedly, wash it with ethanol, centrifuge it, and finally dry it to constant weight at 70 °C to obtain a synergistic flame retardant; (5) Take 80 g of ABS, 15 g of tetrabromobisphenol A, 3 g of synergistic flame retardant, and 0.1 g of antioxidant, mix and stir evenly to obtain a mixture, and extrude and granulate the mixture from an extruder to obtain an ABS composite material with good flame retardancy; among them, the head temperature of the twin-screw extruder is 200 °C and the screw speed is 200 r / min.

[0024] Example 2: An ABS composite material with good flame retardancy, and the specific preparation steps are as follows: (1) Mix 3.5 g of ferric nitrate, 1.5 g of ferrous chloride, 3.5 g of ammonia water, 3.5 g of absolute ethanol, and 7.5 g of deionized water, react in a reaction vessel at 80 °C for 13 h, cool to room temperature, filter, wash the product, and dry it at 70 °C for 8 h to obtain magnetite; Place 3.5 g of magnetite, 5.5 g of hydrogen peroxide, 6.5 g of absolute ethanol, and 12 g of deionized water in a reaction vessel, react at 90 °C for 9 h, filter, wash, and dry the product at 80 °C for 7 h to obtain hydroxylated magnetite; (2) Mix 3 g of hydroxylated magnetite, 1.1 g of silane coupling agent KH550, 4 g of absolute ethanol, and 7 g of deionized water, react in a reaction vessel at 90 °C for 9 h, filter, wash, and dry at 80 °C for 7 h to obtain amino-functionalized magnetite; (3) Take 2.8 g of expandable graphite and ultrasonically disperse it in 300 mL of distilled water. Add 2.2 g of EDC and 1.8 g of NHS to the dispersion, mechanically stir for 35 min, then add 2.8 g of amino-functionalized magnetite, ultrasonically disperse for 30 min, and mechanically stir the mixed solution at 85 °C for 2 h, perform magnetic separation, wash, and dry the product at 60 °C for 24 h to obtain functionalized expandable graphite; (4) Place 5.5 g of functionalized expandable graphite in a three-necked flask, add 130 mL of a mixed solution (ethanol:deionized water = 1:1), then mix 2.8 mL of phytic acid and 0.3 g of KH-550 in a beaker evenly and add them to the above mixed solution, place it at 63 °C and stir evenly for reaction for 11 h. After the reaction is completed, filter the product repeatedly, wash it with ethanol and then centrifuge it, and finally dry it at 70 °C to constant weight to obtain a synergistic flame retardant; (5) Take 90 g of ABS, 17 g of tetrabromobisphenol A, 4 g of synergistic flame retardant, and 0.3 g of antioxidant, mix and stir evenly to obtain a mixture, and extrude and granulate the mixture from an extruder to obtain an ABS composite material with good flame retardancy; among them, the head temperature of the twin-screw extruder is 220 °C and the screw speed is 260 r / min.

[0025] Example 3: An ABS composite material with good flame retardancy, and the specific preparation steps are as follows: (1) Mix 4 g of iron nitrate, 1.8 g of ferrous chloride, 4 g of ammonia water, 4 g of absolute ethanol, and 9 g of deionized water, react in a reaction vessel at 90 °C for 16 h, cool to room temperature, filter, wash the product, and dry it at 80 °C for 10 h to obtain iron tetroxide; Place 4 g of iron tetroxide, 6 g of hydrogen peroxide, 8 g of absolute ethanol, and 13 g of deionized water in a reaction vessel together, react at 100 °C for 10 h, filter, wash, and dry the product at 90 °C for 8 h to obtain hydroxylated iron tetroxide; (2) Mix 3.2 g of hydroxylated iron tetroxide, 1.2 g of silane coupling agent KH550, 4.2 g of absolute ethanol, and 8 g of deionized water, react in a reaction vessel at 100 °C for 8 - 10 h, filter, wash, and dry at 90 °C for 8 h to obtain amino-functionalized iron tetroxide; (3) Take 3 g of expandable graphite and ultrasonically disperse it in 400 mL of distilled water. Add 2.3 g of EDC and 2 g of NHS to the dispersion, mechanically stir for 40 min, then add 3 g of amino-functionalized iron tetroxide, ultrasonically disperse for 30 min, mechanically stir the mixed solution at 90 °C for 2 h, perform magnetic separation, wash, and dry the product at 60 °C for 24 h to obtain functionalized expandable graphite; (4) Place 6 g of functionalized expandable graphite in a three-necked flask, add 150 mL of a mixed solution (ethanol:deionized water = 1:1). Subsequently, mix 3 mL of phytic acid and 0.4 g of KH-550 in a beaker evenly and add it to the above mixed solution, place it at 65 °C and stir evenly for 12 h. After the reaction ends, filter the product repeatedly, wash it with ethanol and then centrifuge, and finally dry it at 70 °C to constant weight to obtain a synergistic flame retardant; (5) Take 100 g of ABS, 18 g of tetrabromobisphenol A, 5 g of synergistic flame retardant, and 0.5 g of antioxidant, mix and stir evenly to obtain a mixed material. Extrude and pelletize the mixed material from an extruder to obtain an ABS composite with good flame retardancy; among them, the head temperature of the twin-screw extruder is 230 °C and the screw speed is 280 r / min.

[0026] Comparative Example 1: The difference from Example 2 is that phytic acid is not used to modify the functionalized expandable graphite. The specific steps are as follows: (1) Mix 3.5 g of iron nitrate, 1.5 g of ferrous chloride, 3.5 g of ammonia water, 3.5 g of absolute ethanol, and 7.5 g of deionized water, react in a reaction vessel at 80 °C for 13 h, cool to room temperature, filter, wash the product, and dry it at 70 °C for 8 h to obtain iron tetroxide; Place 3.5 g of iron tetroxide, 5.5 g of hydrogen peroxide, 6.5 g of absolute ethanol, and 12 g of deionized water in a reaction vessel together, react at 90 °C for 9 h, filter, wash, and dry the product at 80 °C for 7 h to obtain hydroxylated iron tetroxide; (2) Mix 3 g of hydroxylated magnetite, 1.1 g of silane coupling agent KH550, 4 g of absolute ethanol, and 7 g of deionized water, react in a reaction vessel at 90 °C for 9 h, filter, wash, and dry at 80 °C for 7 h to obtain amino-functionalized magnetite; (3) Take 2.8 g of expandable graphite and ultrasonically disperse it in 300 mL of distilled water. Add 2.2 g of EDC and 1.8 g of NHS to the dispersion. After mechanical stirring for 35 min, add 2.8 g of amino-functionalized magnetite and ultrasonically disperse for 30 min. Mechanically stir the mixed solution at 85 °C for 2 h, perform magnetic separation, wash, and dry the product at 60 °C for 24 h to obtain a synergistic flame retardant; (4) Take 90 g of ABS, 17 g of tetrabromobisphenol A, 4 g of synergistic flame retardant, and 0.3 g of antioxidant, mix and stir evenly to obtain a mixture. Extrude and pelletize the mixture from an extruder to obtain an ABS composite with good flame retardancy; among them, the head temperature of the twin-screw extruder is 220 °C and the screw speed is 260 r / min.

[0027] Comparative Example 2: The difference from Example 2 is that expandable graphite is not modified with magnetite. The specific steps are as follows: (1) Place 5.5 g of expandable graphite in a three-necked flask, add 130 mL of a mixed solution (ethanol:deionized water = 1:1). Subsequently, mix 2.8 mL of phytic acid and 0.3 g of KH-550 evenly in a beaker and add them to the above mixed solution. Place it under uniform stirring at 63 °C for 11 h. After the reaction ends, repeatedly filter the product, wash it with ethanol, centrifuge it, and finally dry it at 70 °C to constant weight to obtain a synergistic flame retardant; (2) Take 90 g of ABS, 17 g of tetrabromobisphenol A, 4 g of synergistic flame retardant, and 0.3 g of antioxidant, mix and stir evenly to obtain a mixture. Extrude and pelletize the mixture from an extruder to obtain an ABS composite with good flame retardancy; among them, the head temperature of the twin-screw extruder is 220 °C and the screw speed is 260 r / min.

[0028] Comparative Example 3: The difference from Example 2 is that amino-functionalized magnetite and expandable graphite coated with phytic acid are mixed as a synergistic flame retardant. The specific steps are as follows: (1) Mix 3.5 g of ferric nitrate, 1.5 g of ferrous chloride, 3.5 g of ammonia water, 3.5 g of absolute ethanol, and 7.5 g of deionized water, react in a reaction vessel at 80 °C for 13 h, cool to room temperature, filter, wash the product, and dry at 70 °C for 8 h to obtain magnetite; Place 3.5 g of magnetite, 5.5 g of hydrogen peroxide, 6.5 g of absolute ethanol, and 12 g of deionized water together in a reaction vessel, react at 90 °C for 9 h, filter, wash, and dry the product at 80 °C for 7 h to obtain hydroxylated magnetite; (2) Mix 3 g of hydroxylated magnetite, 1.1 g of silane coupling agent KH550, 4 g of absolute ethanol, and 7 g of deionized water, react in a reaction vessel at 90 °C for 9 h, filter, wash, and dry at 80 °C for 7 h to obtain amino-functionalized magnetite; (3) Place 5.5 g of expandable graphite in a three-necked flask, add 130 mL of a mixed solution (ethanol:deionized water = 1:1), then mix 2.8 mL of phytic acid and 0.3 g of KH-550 in a beaker and add it to the above mixed solution. Stir evenly at 63 °C for 11 h. After the reaction is completed, repeatedly filter the product, wash it with ethanol and then centrifuge it. Finally, dry it to a constant weight at 70 °C, and then mix it with amino-functionalized magnetite in a weight ratio of 1:1 to obtain a synergistic flame retardant; (4) Take 90 g of ABS, 17 g of tetrabromobisphenol A, 4 g of synergistic flame retardant, and 0.3 g of antioxidant, mix and stir evenly to obtain a mixture, and extrude and pelletize the mixture from an extruder to obtain an ABS composite with good flame retardancy; among them, the head temperature of the twin-screw extruder is 220 °C and the screw speed is 260 r / min.

[0029] Comparative Example 4: The difference from Example 2 is that expandable graphite, magnetite, and phytic acid are directly added. The specific steps are as follows: Mix expandable graphite, magnetite, and phytic acid in a weight ratio of 3:3:4 to obtain a synergistic flame retardant; Take 90 g of ABS, 17 g of tetrabromobisphenol A, 4 g of synergistic flame retardant, and 0.3 g of antioxidant, mix and stir evenly to obtain a mixture, and extrude and pelletize the mixture from an extruder to obtain an ABS composite with good flame retardancy; among them, the head temperature of the twin-screw extruder is 220 °C and the screw speed is 260 r / min.

[0030] Performance Test Limiting oxygen index (LOI): Use a limiting oxygen index instrument to test the test specimens. The size of the test specimens is 100 mm × 6.5 mm × 3 mm. Prepare 5 test specimens for each group of samples, and take the average value of the final results; Vertical burning rating (UL-94): Use a vertical burning tester to test the test specimens. The size of the test specimens is 100 mm × 13 mm × 3 mm. Prepare 5 test specimens for each group of samples, and take the average value of the final results; Tensile experiment: Conduct the experiment according to GB / T 1039-1992. The size of the test specimens is 75 mm in length, 5 mm in width, and 2 mm in thickness. Test with a tensile rate of 50 mm / min on a tensile testing machine. Conduct tests on 5 test specimens for each group, and take the average value of the final test results; Impact test: The test was carried out according to GB / T 1043-1993. The dimensions of the spline were 80 mm in length, 10 mm in width, and 4 mm in thickness. Five splines were tested in each group, and the final test results were averaged; the test results are shown in Table 1.

[0031] Table 1 Performance test results LOI (%) UL-94 Tensile strength (MPa) <![CDATA[Impact strength (KJ / m 2 )]]> Example 1 29.7 V-0 34.6 20.3 Example 2 30.4 V-0 35.4 21.7 Example 3 28.9 V-0 33.6 20.4 Comparative Example 1 28.4 V-0 30.5 15.8 Comparative Example 2 28.6 V-0 32.4 16.4 Comparative Example 3 29.8 V-0 33.2 17.5 Comparative Example 4 25.7 V-1 26.9 10.5 Data analysis: As can be seen from Examples 1-3 in Table 1, the ABS composite material of the present invention has excellent flame retardancy while also having good tensile strength and impact strength, avoiding the problem of a significant reduction in mechanical strength caused by the addition of flame retardants in traditional flame-retardant ASB materials.

[0032] From Examples 2 and Comparative Examples 1 and 2 in Table 1, it can be seen that by grafting iron oxide and phytic acid onto the surface of expandable graphite, the flame retardancy and mechanical strength of the ABS composite material are improved to a certain extent. This is mainly because on the one hand, expandable graphite can provide an expanding flame-retardant skeleton, and both iron oxide and phytic acid have certain flame-retardant capabilities. At the same time, the use of silane coupling agent and phytic acid can modify the surface of expandable graphite to a certain extent, thereby adjusting the interfacial compatibility between expandable graphite and ABS material, ensuring a certain level of mechanical performance.

[0033] From Example 2 and Comparative Example 3, it can be seen that in the present invention, iron oxide is first grafted onto the surface of expandable graphite and then used as a "nano-bridge" to connect phytic acid with expandable graphite, so that phytic acid is coated on the surface of expandable graphite to form a synergistic flame retardant, making the flame retardancy and mechanical properties of the ABS composite material maintain an excellent level. This may be because the pre-grafted iron oxide can insert into the interlayer of expandable graphite to form "nano-rivets", and at the same time can provide more active sites for the loading of phytic acid, enabling more phytic acid to be loaded on the surface of expandable graphite, thereby improving the flame retardant ability. In addition, it can improve the density of expandable graphite, and more phytic acid can further coat expandable graphite, further promoting its compatibility with the matrix resin, thus ensuring a certain level of mechanical performance. On the other hand, this interfacial gradient design can achieve the co-optimization of flame retardancy and mechanical properties through the triple synergy of chemical bonding - catalysis - structure enhancement. Moreover, this interfacial gradient design can enable phytic acid to coat expandable graphite and iron oxide, further enhancing its compatibility with the matrix.

[0034] It can be seen from Example 2 and Comparative Example 3 that directly mixing expandable graphite, iron tetroxide, and phytic acid as a synergistic flame retardant and adding it directly improves the flame retardant performance of the composite material to a certain extent, but causes a significant damage to the mechanical properties of the composite material. This is mainly because its distribution in the matrix is uneven and its compatibility with the matrix is poor.

[0035] Those of ordinary skill in the art should understand that the discussion of any above embodiment is only exemplary and is not intended to imply that the scope of the present invention is limited to these examples; under the concept of the present invention, the technical features in the above embodiments or different embodiments can also be combined, the steps can be implemented in any order, and there are many other variations in different aspects of the present invention as described above, which are not provided in detail for the sake of brevity.

Claims

1. An ABS composite material with good flame retardancy, characterized in that: The raw materials include the following parts by weight: 80-100 parts of ABS, 15-18 parts of tetrabromobisphenol A, 3-5 parts of synergistic flame retardant, and 0.1-0.5 parts of antioxidant; The preparation steps of the synergistic flame retardant are as follows: S1: Mix ferroferric oxide, hydrogen peroxide, anhydrous ethanol and deionized water, react at 80-100°C for 8-10h, and purify to obtain hydroxylated ferroferric oxide; S2: Mix hydroxylated ferrosoferric oxide, silane coupling agent KH550, anhydrous ethanol and deionized water, react at 80-100° C. for 8-10 hours, and purify to obtain amination ferrosoferric oxide; S3: dispersing expandable graphite in distilled water, adding EDC and NHS, and then adding amino ferric oxide, ultrasonically homogenizing, stirring at 80-90°C for 1-2 h, and purifying to obtain functionalized expandable graphite; S4: Dispersing the functionalized expandable graphite in the mixed solution, then adding phytic acid and KH-550, and reacting at 60-65°C for 10-12 h. After the reaction is completed, purifying the product to obtain a synergistic flame retardant; The weight ratio of ferroferric oxide, hydrogen peroxide, anhydrous ethanol and deionized water in step S1 is 3-4g: 5-6g: 6-8g: 11-13g; The weight ratio of hydroxylated ferrosoferric oxide, silane coupling agent KH550, anhydrous ethanol and deionized water in step S2 is 2.8-3.2 g: 1-1.2 g: 3.6-4.2 g: 6-8 g; The usage ratio of expandable graphite, distilled water, EDC, NHS and amination of ferrosoferric oxide in step S3 is 2.5-3 g: 200-400 mL: 2.1-2.3 g: 1.5-2 g: 2.5-3 g; The usage ratio of the functionalized expandable graphite, the mixed solution, phytic acid and KH-550 in step S4 is 5-6 g: 100-150 mL: 2.5-3 mL: 0.25-0.4 g.

2. The ABS composite material with good flame retardancy according to claim 1, characterized in that: The ferroferric oxide in step S1 is homemade, and the specific preparation steps are as follows: ferric nitrate, ferrous chloride, ammonia water, anhydrous ethanol and deionized water are mixed, reacted at 70-90° C. for 10-16 hours, filtered, washed and dried to obtain ferroferric oxide.

3. The ABS composite material with good flame retardancy according to claim 2, characterized in that: The weight ratio of the ferric nitrate, ferrous chloride, ammonia water, anhydrous ethanol and deionized water is 3-4g:1.2-1.8g:3-4g:3-4g:7-9g.

4. The ABS composite material with good flame retardancy according to claim 1, characterized in that: The particle size of the expandable graphite in step S3 is 150-200 μm.

5. The ABS composite material with good flame retardancy according to claim 1, characterized in that: The mixed solution in step S4 is a mixture of ethanol and deionized water in a volume ratio of 1:

1.

6. The ABS composite material with good flame retardancy according to claim 1, characterized in that: The ABS was purchased from Daqing Petrochemical, model 750A.

7. The ABS composite material with good flame retardancy according to claim 1, characterized in that: The antioxidant is one of the antioxidant Irganox168, antioxidant Irganox1010 and antioxidant Irganox1330.

8. A method for preparing an ABS composite material with good flame retardancy according to any one of claims 1 to 7, characterized in that: The following steps are involved: ABS, tetrabromobisphenol A, synergistic flame retardant and antioxidant are weighed according to the weight proportions of the raw materials, mixed and stirred evenly to obtain a mixture, which is then extruded and granulated from an extruder to obtain an ABS composite material with good flame retardant properties.

9. The preparation method according to claim 8, characterized in that: The extruder is a twin-screw extruder, which includes six temperature zones arranged in sequence, namely, zone one temperature 180-210°C, zone two temperature 200-230°C, zone three temperature 200-230°C, zone four temperature 200-230°C, zone five temperature 200-230°C, zone six temperature 200-230°C; the head temperature of the twin-screw extruder is 200-230°C, and the screw speed is 200-280r / min.