A kind of ABS conductive plastic and preparation method thereof

Abstract

The present invention provides an ABS conductive plastic, the raw materials of which include: 72-90 parts by weight of ABS material, 5-20 parts by weight of carbon black, and 5-8 parts by weight of metal short fibers. The present invention uses ABS as a base material and mixes it with a conductive additive, and processes it in a plastic processing and molding manner. The present invention realizes the change from an insulator to a semiconductor and then to a conductor. Compared with traditional ABS materials, the present invention has the characteristics of light weight, easy molding, adjustable resistivity, etc., and can be conveniently synthesized or compounded into materials with various structures through molecular design.

Description

Technical Field

[0001] The invention belongs to the technical field of plastic modification, and in particular relates to an ABS conductive plastic and a preparation method thereof. Background Art

[0002] Plastics have been used as insulating materials. Due to their high insulation, they bring some problems in processing and application, the most prominent of which is the phenomenon of static electricity, which will lead to the degradation of the performance of photosensitive films and catastrophic accidents caused by polymer products in flammable and explosive places. With the development of modern electronic industry and information industry, various industrial automation equipment, microcomputers, household appliances and electronic products have entered various fields of the national economy and people's working and living environment. Technologies such as static elimination, electromagnetic shielding, and micro-wave absorption have attracted people's attention. Therefore, the application field has put forward the requirements of conductive properties for plastics. In the past decade, countries around the world have carried out extensive research on plastics, striving to launch a new generation of plastic materials that not only maintain the inherent advantages of plastics but also give them new conductive properties.

[0003] ABS plastic is a raw material formed by the combination of acrylonitrile, butadiene and styrene. It has excellent impact resistance, heat resistance, low temperature resistance, chemical resistance and electrical properties. It is also easy to process, the product size is stable, and the surface gloss is good. It is easy to paint and color, and can also undergo secondary processing such as surface metal spraying, electroplating, welding, hot pressing and bonding. It is widely used in industrial fields such as machinery, automobiles, electronic appliances, instruments and meters, textiles and construction. It is a thermoplastic engineering plastic with extremely wide uses.

[0004] The uses of conductive plastics generally include the following aspects: 1) Anti-static turnover boxes, IC and LCD trays, IC packaging, chip carriers, film bags, etc. used in the production process of precision electronic components such as integrated circuits, chips, sensor sheaths, etc. in the fields of electronics and electrical appliances; 2) Shells and structural parts of explosion-proof products, such as shells and structural parts of electrical products used in coal mines, oil tankers, oil fields, dust and combustible gases, etc.; 3) Semi-conductive shielding materials used in medium and high voltage cables; 4) EMI shielding shells of electrical products in the fields of telecommunications, computers, automation systems, industrial electronic products, consumer electronic products, automotive electronic products, etc.

[0005] The present invention further modifies the ABS material so that it can be conductive while retaining the inherent advantages of the ABS material. Compared with metal materials, the present invention has the following advantages: the shielding effectiveness of the ABS material can be designed according to product requirements; it has a long service life; it can process products with more complex structures; it does not require secondary processing, resulting in less waste and a short production cycle; it has low production losses and reduces production costs; the seams do not require shielding pads, reducing installation time and costs; it has low density and reduces transportation costs. Summary of the invention

[0006] The present invention provides an ABS conductive plastic, which is mixed with ABS as a base material and a conductive additive and processed by a plastic processing and molding method. The present invention realizes the change from an insulator to a semiconductor and then to a conductor. Compared with traditional ABS materials, the present invention has the characteristics of light weight, easy molding, adjustable resistivity, etc., and can be conveniently synthesized or compounded into materials with various structures through molecular design.

[0007] To achieve the above objectives, the specific plan is as follows:

[0008] An ABS conductive plastic comprises raw materials including: 72-90 parts by weight of ABS material, 5-20 parts by weight of carbon black, and 5-8 parts by weight of metal short fibers.

[0009] As a further elaboration of the present invention:

[0010] Preferably, the proportions of acrylonitrile, butadiene and styrene in the ABS material are: 1:0.32-0.54:2.35-2.40.

[0011] Preferably, the carbon black has a particle size of 12-20 nm, a resistivity of 0.8-1.0 Ω·m, and a sieve residue of ≤0.02%.

[0012] Preferably, the metal short fibers are selected from one or more of copper fibers, silver fibers, nickel fibers or stainless steel fibers, and their resistivity is 10 -3 -10 0 Ω.cm, aspect ratio is 80-120.

[0013] Preferably, the metal short fibers are a mixture of copper fibers and stainless steel fibers, and the weight ratio is 0.01-0.69:0.31-0.99.

[0014] A method for preparing the above-mentioned ABS conductive plastic comprises the following steps: a. drying ABS material at 120-130°C for 2-3 hours through ventilation to obtain dry ABS material; b. starting a kneader with a kneading blade speed ratio of 2:1 to run idle for 10-15 minutes, and weighing dry ABS material and carbon black according to weight ratio; c. adding the weighed dry ABS material and carbon black into the kneader, evacuating to -0.05Mpa, heating to 220-230°C, and fully kneading for 30-50 minutes; d. raising the kneading temperature to 230-240°C, injecting metal short fibers into the kneader, kneading for 2-6 minutes, and obtaining a polymer mixture; e. adding the mixture obtained in step d into a screw extruder, extruding it at 185-200°C through melt mixing and granulation, and obtaining ABS conductive plastic.

[0015] Preferably, the carbon black is prepared by acetylene cracking and pyrolysis, comprising the following steps: a. generating a high-temperature combustion airflow in a reaction furnace, maintaining a temperature of 1600-1700°C, and allowing acetylene gas with a pressure of 600-700 mm water column to enter the furnace through the top of the reaction furnace; b. after the acetylene gas is cracked, the generated carbon black is suspended in the high-temperature airflow and cooled by indirect heat exchange with jacket water; c. separating and collecting the carbon black, and then suspending the collected carbon black in the airflow again and passing it through a pulverizer to remove fine lumps therein; d. grinding the carbon black by a grinder to a particle size of 12-20 nm.

[0016] Preferably, the preparation method of the metal staple fibers comprises the following steps: a. pre-treating the selected metal fibers: rinsing away dust and impurities on the surface with clean water; b. surface active treatment: enhancing the compatibility and bonding degree between the fibers and the polymer mixture and improving the electrical conductivity; c. extrusion: using a twin-screw extruder with a speed adjusted to 420-430 r / min to extrude the fibers uniformly and dispersedly to obtain the metal staple fibers.

[0017] Preferably, in step b, the surfactant is an organic silane coupling agent or a titanate coupling agent.

[0018] The difference between the present invention and the prior art is that the present invention achieves the following technical effects:

[0019] First, the raw materials of the present invention include: 72-90 parts by weight of ABS material, 5-20 parts by weight of carbon black, and 5-8 parts by weight of metal short fibers. The proportions of acrylonitrile, butadiene and styrene in the ABS material are: 1:0.32-0.54:2.35-2.40. The ABS conductive plastic is prepared by kneading with carbon black and metal short fibers. The process steps are simple, the production cost is low, and the plastic has the characteristics of light weight, easy molding, adjustable resistivity, etc.

[0020] Secondly, the present invention adds carbon black conductive filler, and the carbon black is obtained by pyrolysis of acetylene, so that the resistivity of ABS conductive plastic can be adjusted by selecting a suitable amount of carbon black. Adding a small amount of carbon black will not change the resistivity significantly. After the amount of carbon black is increased to a certain proportion, the resistivity can be reduced by several orders of magnitude. However, after it drops to a lower limit, the resistivity change is not obvious when the amount of carbon black is increased. Combined with the addition of metal short fibers and the preparation method of metal short fibers, the preparation method of metal short fibers can improve the aspect ratio of metal short fibers, so that the resistivity and aspect ratio of metal short fibers are appropriate. Controlling the amount of metal short fibers and the kneading time is helpful to improve the conductive performance, and the materials can be conveniently synthesized or compounded into various structures through molecular design.

[0021] Third, the present invention modifies the ABS material so that it can be conductive while retaining the inherent advantages of the ABS material, realizing the change from an insulator to a semiconductor and then to a conductor. Compared with metal materials, the shielding effectiveness of the ABS material can be designed according to product requirements; it has a long service life; it can process products with more complex structures; it does not require secondary processing, has less waste, and has a short production cycle; it has low production losses and reduces production costs; the seams do not require shielding pads, reducing installation time and costs; it has a low density and reduces transportation costs. DETAILED DESCRIPTION

[0022] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0023] Embodiment 1:

[0024] An ABS conductive plastic, the raw materials include: 90 parts by weight of ABS material, 5 parts by weight of carbon black, and 5 parts by weight of metal short fibers. The proportions of acrylonitrile, butadiene and styrene in the ABS material are 1:0.32:2.35.

[0025] The carbon black is prepared by pyrolysis of acetylene, and comprises the following steps: a. generating a high-temperature combustion airflow in a reaction furnace, the temperature of which is maintained at 1600-1700°C, and allowing acetylene gas with a pressure of 600-700 mm water column to enter the furnace through the top of the reaction furnace; b. after the acetylene gas is cracked, the generated carbon black is suspended in the high-temperature airflow and cooled by indirect heat exchange with jacket water; c. separating and collecting the carbon black, and then suspending the collected carbon black in the airflow again and passing it through a pulverizer to remove fine lumps therein; d. grinding the carbon black by a grinder to a particle size of 12-20 nm, a resistivity of 0.8-1.0 Ω·m, and a sieve residue of ≤0.02%.

[0026] The metal short fibers are copper fibers. The preparation method of the metal short fibers comprises the following steps: a. pre-treating the selected metal fibers: using clean water to remove dust and impurities on the surface; b. using a surfactant to perform surface activity treatment on the technical fibers: enhancing the compatibility and bonding degree between the fibers and the polymer mixture and improving the electrical conductivity. The surfactant is an organic silane coupling agent; c. extruding: using a twin-screw extruder with a speed adjusted to 420-430 r / min to disperse and extrude uniformly to obtain the metal short fibers, whose resistivity is 10 -3 -10 0 Ω.cm, aspect ratio is 80-120.

[0027] The preparation method of ABS conductive plastic comprises the following steps: a. drying ABS material under ventilation at 120-130°C for 2-3 hours to obtain dry ABS material; b. starting a kneader with a kneading blade speed ratio of 2:1 to run idly for 10-15 minutes, and weighing dry ABS material and carbon black according to weight ratio; c. adding the weighed dry ABS material and carbon black into the kneader, evacuating to -0.05Mpa, heating to 220-230°C, and fully kneading for 30-50 minutes; d. heating the kneading temperature to 230-240°C, injecting metal short fibers into the kneader, kneading for 2 minutes, and obtaining a polymer mixture; e. adding the mixture obtained in step d into a screw extruder, extruding it at 185-200°C through melt mixing and granulation, and obtaining ABS conductive plastic.

[0028] Embodiment 2:

[0029] An ABS conductive plastic, the raw materials include: 72 parts by weight of ABS material, 20 parts by weight of carbon black, and 8 parts by weight of metal short fibers. The proportions of acrylonitrile, butadiene and styrene in the ABS material are 1:0.54:2.40.

[0030] The carbon black is prepared by pyrolysis of acetylene, and comprises the following steps: a. generating a high-temperature combustion airflow in a reaction furnace, the temperature of which is maintained at 1600-1700°C, and allowing acetylene gas with a pressure of 600-700 mm water column to enter the furnace through the top of the reaction furnace; b. after the acetylene gas is cracked, the generated carbon black is suspended in the high-temperature airflow and cooled by indirect heat exchange with jacket water; c. separating and collecting the carbon black, and then suspending the collected carbon black in the airflow again and passing it through a pulverizer to remove fine lumps therein; d. grinding the carbon black by a grinder to a particle size of 12-20 nm, a resistivity of 0.8-1.0 Ω·m, and a sieve residue of ≤0.02%.

[0031] The metal short fibers are silver fibers. The preparation method of the metal short fibers comprises the following steps: a. pre-treating the selected metal fibers: using clean water to rinse off dust and impurities on the surface; b. using a surfactant to perform surface activity treatment on the technical fibers: enhancing the compatibility and bonding degree between the fibers and the polymer mixture and improving the electrical conductivity. The surfactant is a titanate coupling agent; c. extruding: using a twin-screw extruder with a speed adjusted to 420-430 r / min to disperse and extrude uniformly to obtain the metal short fibers, whose resistivity is 10 -3 -10 0 Ω.cm, aspect ratio is 80-120.

[0032] The preparation method of ABS conductive plastic comprises the following steps: a. drying ABS material under ventilation at 120-130°C for 2-3 hours to obtain dry ABS material; b. starting a kneader with a kneading blade speed ratio of 2:1 to run idly for 10-15 minutes, and weighing dry ABS material and carbon black according to weight ratio; c. adding the weighed dry ABS material and carbon black into the kneader, evacuating to -0.05Mpa, heating to 220-230°C, and fully kneading for 30-50 minutes; d. raising the kneading temperature to 230-240°C, injecting metal short fibers into the kneader, kneading for 6 minutes, and obtaining a polymer mixture; e. adding the mixture obtained in step d into a screw extruder, extruding it at 185-200°C through melt mixing and cooling, and granulating it to obtain ABS conductive plastic.

[0033] Embodiment 3:

[0034] An ABS conductive plastic, the raw materials include: 83 parts by weight of ABS material, 10 parts by weight of carbon black, and 7 parts by weight of metal short fibers. The proportions of acrylonitrile, butadiene and styrene in the ABS material are 1:0.35:2.38.

[0035] The carbon black is prepared by pyrolysis of acetylene, and comprises the following steps: a. generating a high-temperature combustion airflow in a reaction furnace, the temperature of which is maintained at 1600-1700°C, and allowing acetylene gas with a pressure of 600-700 mm water column to enter the furnace through the top of the reaction furnace; b. after the acetylene gas is cracked, the generated carbon black is suspended in the high-temperature airflow and cooled by indirect heat exchange with jacket water; c. separating and collecting the carbon black, and then suspending the collected carbon black in the airflow again and passing it through a pulverizer to remove fine lumps therein; d. grinding the carbon black by a grinder to a particle size of 12-20 nm, a resistivity of 0.8-1.0 Ω·m, and a sieve residue of ≤0.02%.

[0036] The metal short fiber is nickel fiber, and the preparation method of the metal short fiber includes the following steps: a. pre-treating the selected metal fiber: using clean water to rinse off the dust and impurities on the surface; b. using a surfactant to perform surface activity treatment on the technical fiber: enhancing the compatibility and bonding degree between the fiber and the polymer mixture and improving the electrical conductivity, and the surfactant is an organic silane coupling agent; c. extruding: using a twin-screw extruder with a speed adjusted to 420-430r / min to disperse and extrude uniformly to obtain the metal short fiber, whose resistivity is 10 -3 -10 0 Ω.cm, aspect ratio is 80-120.

[0037] The preparation method of ABS conductive plastic comprises the following steps: a. drying ABS material under ventilation at 120-130°C for 2-3 hours to obtain dry ABS material; b. starting a kneader with a kneading blade speed ratio of 2:1 to idle for 10-15 minutes, and weighing dry ABS material and carbon black according to weight ratio; c. adding the weighed dry ABS material and carbon black into the kneader, evacuating to -0.05Mpa, heating to 220-230°C, and fully kneading for 30-50 minutes; d. heating the kneading temperature to 230-240°C, injecting metal short fibers into the kneader, kneading for 5 minutes, and obtaining a polymer mixture; e. adding the mixture obtained in step d into a screw extruder, extruding it at 185-200°C through melt mixing and granulation, and obtaining ABS conductive plastic.

[0038] Embodiment 4:

[0039] The metal short fibers are stainless steel fibers, and the rest are the same as in Example 3.

[0040] Embodiment 5:

[0041] The metal short fibers are a mixture of copper fibers and stainless steel fibers, and the weight ratio is 0.01:0.99. Other aspects are the same as those of Example 3.

[0042] Embodiment 6:

[0043] The metal short fibers are a mixture of copper fibers and stainless steel fibers, and the weight ratio is 0.69:0.31. Other aspects are the same as those of Example 3.

[0044] Embodiment 7:

[0045] The metal short fibers are a mixture of copper fibers and stainless steel fibers, and the weight ratio is 0.53:0.47. Other aspects are the same as those of Example 3.

[0046] Embodiment 8:

[0047] An ABS conductive plastic, the raw materials include: 84 parts by weight of ABS material, 8 parts by weight of carbon black, and 6 parts by weight of metal short fibers. The proportions of acrylonitrile, butadiene and styrene in the ABS material are 1:0.45:2.37.

[0048] The carbon black is prepared by pyrolysis of acetylene, and comprises the following steps: a. generating a high-temperature combustion airflow in a reaction furnace, the temperature of which is maintained at 1600-1700°C, and allowing acetylene gas with a pressure of 600-700 mm water column to enter the furnace through the top of the reaction furnace; b. after the acetylene gas is cracked, the generated carbon black is suspended in the high-temperature airflow and cooled by indirect heat exchange with jacket water; c. separating and collecting the carbon black, and then suspending the collected carbon black in the airflow again and passing it through a pulverizer to remove fine lumps therein; d. grinding the carbon black by a grinder to a particle size of 12-20 nm, a resistivity of 0.8-1.0 Ω·m, and a sieve residue of ≤0.02%.

[0049] The metal short fiber is a mixture of copper fiber and stainless steel fiber, and the weight ratio is 0.38:0.62. The preparation method of the metal short fiber includes the following steps: a. pre-treating the selected metal fiber: rinsing the dust and impurities on the surface with clean water; b. surface active treatment of the technical fiber with a surfactant: enhancing the compatibility and bonding degree of the fiber with the polymer mixture and improving the conductivity, and the surfactant is an organic silane coupling agent; c. extrusion: using a twin-screw extruder with a speed adjusted to 420-430r / min to disperse and extrude evenly to obtain the metal short fiber.

[0050] The preparation method of ABS conductive plastic comprises the following steps: a. drying ABS material under ventilation at 120-130°C for 2-3 hours to obtain dry ABS material; b. starting a kneader with a kneading blade speed ratio of 2:1 to idle for 10-15 minutes, and weighing dry ABS material and carbon black according to weight ratio; c. adding the weighed dry ABS material and carbon black into the kneader, evacuating to -0.05Mpa, heating to 220-230°C, and fully kneading for 30-50 minutes; d. heating the kneading temperature to 230-240°C, injecting metal short fibers into the kneader, kneading for 5 minutes, and obtaining a polymer mixture; e. adding the mixture obtained in step d into a screw extruder, extruding it at 185-200°C through melt mixing and granulation, and obtaining ABS conductive plastic.

[0051] Embodiment 9:

[0052] A conductive ABS plastic, comprising raw materials including: 84 parts by weight of ABS material, 12 parts by weight of carbon black, 4 parts by weight of metal short fibers, and other ingredients are the same as those in Example 8.

[0053] Embodiment 10:

[0054] A conductive ABS plastic, comprising raw materials including: 75 parts by weight of ABS material, 16 parts by weight of carbon black, 9 parts by weight of metal short fibers, and other ingredients are the same as those in Example 8.

[0055] Embodiment 11:

[0056] After the metal short fibers were injected into the kneading machine, they were kneaded for 1.5 minutes. The rest was the same as in Example 8.

[0057] Embodiment 12:

[0058] After the metal short fibers were injected into the kneading machine, the kneading was performed for 7 minutes. The rest was the same as in Example 8.

[0059] The ABS conductive plastics prepared in the above Examples 1 to 12 were molded into ABS conductive plastic plates with the same shape, size and thickness of 0.3 mm, and the performance was tested with ABS conductive plastic plates of the same shape and thickness on the market. The results are as follows:

[0060]

[0061] Based on the data obtained from the above embodiments, the inventors analyzed as follows: The ABS conductive plastic plates prepared by the present invention in Embodiments 1 to 12 have performances similar to those on the market in terms of tensile strength, flexural strength, elongation at break, notched impact strength and heat deformation temperature, and fully meet the application requirements in industrial fields such as machinery, automobiles, electronic appliances, instruments and meters, textiles and construction. As for plastics, the volume resistivity is generally between 0.001-5Ω.cm, that is, it meets the conductivity requirement. The optimal resistance range of the conductive shell is between 0.001-0.04Ω.cm. It is not difficult to see from the experiment that the volume resistivity of Examples 5 to 8 is smaller than that of other examples, and the volume resistivity of Example 8 is the smallest; in Examples 9 and 10, the volume resistivity is larger because the amount of metal short fibers added is too little or too much compared with that of Examples 1 to 8; in Examples 11 and 12, the volume resistivity is larger because the kneading time after the metal short fibers are injected into the kneading machine is too short or too long compared with that of Examples 1 to 8; in Examples 5 to 8, the metal short fibers are a mixture of copper fibers and stainless steel fibers, and the volume resistivity is smaller than that of Examples 1 to 4.

[0062] The present invention modifies the ABS material so that it can be conductive while retaining the inherent advantages of the ABS material, realizing the change from an insulator to a semiconductor and then to a conductor. Compared with metal materials, the shielding effectiveness of the ABS material can be designed according to product requirements; it has a long service life; it can process products with more complex structures; it does not require secondary processing, has less waste, and has a short production cycle; it has low production losses and reduces production costs; the seams do not require shielding pads, reducing installation time and costs; it has low density and reduces transportation costs. ABS is mixed as a base material and a conductive additive, and processed in a plastic processing and molding manner, realizing the change from an insulator to a semiconductor and then to a conductor. Compared with traditional ABS materials, it has the characteristics of light weight, easy molding, and adjustable resistivity, and can be conveniently synthesized or compounded into materials with various structures through molecular design.

[0063] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. An ABS conductive plastic, characterized in that: Ingredients include: 83-84 parts by weight of ABS material, 8-10 parts by weight of carbon black, and 6-8 parts by weight of metal short fibers; the proportions of acrylonitrile, butadiene and styrene in the ABS material are: 1:0.35-0.45:2.37-2.38; the particle size of the carbon black is 12-20nm, the resistivity is 0.8-1.0Ω·m, and the sieve residue is ≤0.02%; the metal short fibers are a mixture of copper fibers and stainless steel fibers, and the weight ratio is: 0.38-0.53:0.47-0.62, and the resistivity is 10 -3 -10 0 Ω.cm, and the aspect ratio is 80-120; the carbon black is prepared by thermal cracking of acetylene, comprising the following steps: a. generating a high-temperature combustion gas flow in a reaction furnace, the temperature of which is maintained at 1600-1700°C, and allowing acetylene gas with a pressure of 600-700 mm of water column to enter the furnace through the top of the reaction furnace; b. after the acetylene gas is cracked, the generated carbon black is suspended in the high-temperature gas flow and cooled by indirect heat exchange with jacket water; c. Separate and collect the carbon black, and then suspend the collected carbon black in the air flow again and pass it through a pulverizer to remove fine lumps; d. Grind the carbon black through a grinder to a particle size of 12-20nm; The preparation method of the metal short fiber includes the following steps: a. Pre-treat the selected metal fiber: rinse off the dust and impurities on the surface with clean water; b. Surface active treatment: enhance the compatibility and bonding degree of the fiber and the polymer mixture, and improve the conductive performance; c. Extrusion: using a twin-screw extruder with a speed adjusted to 420-430r / min to extrude uniformly to obtain metal short fibers; the preparation method of the ABS conductive plastic comprises the following steps: a. ventilating and drying the ABS material at a temperature of 120°C-130°C for 2-3 hours to obtain dry ABS material; b. starting a kneading machine with a kneading blade speed ratio of 2:1 to run idly for 10-15 minutes, and weighing dry ABS material and carbon black according to weight ratio; c. adding the weighed dry ABS material and carbon black to the kneading machine, evacuating to -0.05Mpa, heating to 220-230°C, and fully kneading for 30-50 minutes; d. raising the kneading temperature to 230-240°C, injecting the metal short fibers into the kneading machine, kneading for 5 minutes, and obtaining a polymer mixture; e. adding the mixture obtained in step d to a screw extruder, extruding it at 185-200°C through melt mixing, cooling and granulating, and obtaining ABS conductive plastic.

2. The ABS conductive plastic according to claim 1, characterized in that: In the method for preparing metal short fibers, in step b, the surfactant is selected from an organic silane coupling agent or a titanate coupling agent.

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