A high-conductivity and thermal-conductivity enhanced polyphenylene sulfide composite filled with black talcum powder and a preparation method thereof

Abstract

The invention relates to the technical field of plastic modification and processing, in particular to a highly conductive and thermally conductive reinforced polyphenylene sulfide composite filled with black talcum powder; the PPS composite is a PPS composite material based on a highly conductive composite system coated with black talcum powder, and the mass percentage composition of the PPS composite is as follows: 75.0-86.0 wt.% of PPS resin, 10.0-21.0 wt.% of black talcum powder coated with a highly conductive composite system, 2.0-3.0 wt.% of ferric chloride powder, 0.5-1.0 wt.% of a dispersant, 0.1-0.15 wt.% of a primary antioxidant, and 0.1-0.15 wt.% of an auxiliary antioxidant; the invention coats the black talcum powder with a highly conductive composite system, establishes an electron path between an internal graphite layer and an outer coating layer thereof, and when the black talcum powder is used for PPS filling and modification, not only the strength, modulus, rigidity, surface hardness and dimensional stability of the PPS are improved, but also the electrical conductivity and thermal conductivity of the PPS can be significantly enhanced, thereby achieving the effect of killing two birds with one stone.

Description

Technical Field

[0001] The invention relates to the technical field of plastic modification and processing, in particular to a high-conductivity and heat-conductivity enhanced polyphenylene sulfide composite filled with black talcum powder and a preparation method thereof. Background Art

[0002] PPS is a special engineering plastic with excellent comprehensive performance, characterized by outstanding thermal stability, excellent mechanical properties, excellent chemical stability, creep resistance, rigidity, electrical insulation and good processing performance. It is widely used in the fields of industry and electronic appliances. PPS is a crystalline polymer. When it is used in the manufacture of industrial machinery and structural components, it often exhibits excessive rigidity but insufficient toughness. Therefore, it is necessary to add reinforcements to improve its tensile and bending strength. These reinforcements include glass fiber, carbon fiber, and various layered silicate fillers. These reinforcements can not only produce effective reinforcement by limiting the plastic movement of PPS molecular chains when the material is subjected to external forces, but also can play a heterogeneous nucleation effect to promote PPS crystallization, thereby further improving its mechanical strength. Therefore, reinforced PPS composites can often exhibit strength and mechanical properties similar to steel. However, PPS itself is a thermoplastic organic polymer material. Even after reinforcement and modification, it does not have the high electrical conductivity and thermal conductivity of steel. In order to make the reinforced PPS composite material have good electrical conductivity and thermal conductivity, it is necessary to continue to add a large amount of conductive fillers (such as carbon black, graphite, graphene, carbon nanotubes, etc.) or thermal conductive fillers (such as boron nitride, silicon carbide, aluminum oxide, etc.). Although this measure improves the electrical conductivity and thermal conductivity of the reinforced PPS composite material, it leads to a decrease in its mechanical properties, making it difficult to achieve simultaneous improvement of functional modification and mechanical performance enhancement.

[0003] Black talcum powder is an emerging magnesium silicate-rich filler material discovered in recent years. It has a layered structure unique to traditional talcum powder, which can enhance, increase rigidity, and promote crystallization of thermoplastics. Its layered structure contains different amounts of organic carbon or graphite, which makes it appear black or gray. Therefore, black talcum powder can partially replace traditional talcum powder for special materials for non-white plastic products, which can effectively improve the surface hardness, tensile strength and modulus, bending strength and modulus of plastics, and can also improve the warpage resistance and dimensional stability of plastic products. However, the organic carbon or graphite contained in black talcum powder is surrounded by its magnesium silicate layer, and it is difficult to form an electronic path with the outside world. Therefore, the polymer composites formed by directly filling plastics with black talcum powder cannot obtain improved electrical and thermal conductivity. Its functional modification technology for thermoplastics has yet to be developed. Summary of the invention

[0004] The purpose of the present invention is to provide a highly conductive and thermally conductive reinforced polyphenylene sulfide composite based on black talcum powder filling, in view of the fact that the goals of enhancement and conductive and thermally conductive functional modification cannot be achieved simultaneously during the process of black talcum powder filling and modifying PPS.

[0005] The present invention adopts a high-conductivity composite system formed by in-situ composite of polydopamine, graphene and carbon black to perform in-situ polymerization coating on black talcum powder, and at the same time, iodine is first used as an electron acceptor to penetrate into the black talcum powder interlayer before the in-situ polymerization is implemented, so as to form the doping of the graphite layer by the electron acceptor. In the process of in-situ polymerization coating of dopamine, an internal intercalation structure of a conductive polymer can be formed between the black talcum powder layers, which is connected with the high-conductivity composite coating layer of the outer layer, and an electron path is established between the outer layer of the black talcum powder and the inner layer of organic carbon or graphite, so as to have electronic conductivity and thermal conductivity; then the black talcum powder coated by the high-conductivity composite is melt-blended with PPS, and a solid electron donor compound (such as ferric chloride) is added simultaneously, and PPS is doped by the electron donor, so that PPS obtains more electrons as conductive carriers, thereby further enhancing the conductivity and thermal conductivity of the composite, so that the prepared black talcum powder filled modified PPS composite is enhanced and rigidified, and the conductivity and thermal conductivity are simultaneously improved.

[0006] Another object of the present invention is to provide a method for preparing the above-mentioned high electrical and thermal conductivity enhanced polyphenylene sulfide composite filled with black talc.

[0007] The specific technical solutions are as follows:

[0008] A highly conductive and thermally conductive reinforced polyphenylene sulfide composite filled with black talcum powder, wherein the mass percentage composition of the PPS composite is as follows:

[0009]

[0010] Furthermore, the highly conductive composite system coated black talcum powder is an iodine-doped electron acceptor-doped black talcum powder in situ coated with polydopamine, graphene and carbon black.

[0011] Furthermore, the preparation method of the highly conductive composite system coated with black talcum powder is as follows:

[0012] 1) Put black talcum powder and iodine into a high-speed mixer according to the ratio, mix at high speed for 20 minutes in a closed environment, raise the material temperature to 80°C, then stop stirring, let it stand until the material temperature drops to room temperature, then add silane coupling agent KH-550, mix at high speed for 10 minutes again, stop stirring, let it stand until the material temperature drops to room temperature and take it out;

[0013] 2) The iodine-doped and KH-550-surface-treated black talc powder is dispersed in tris(hydroxymethylaminomethane)-hydrochloride buffer (pH=8.4), dopamine hydrochloride, graphene and carbon black are added in sequence, and mechanical stirring is performed at room temperature, during which the dopamine hydrochloride gradually undergoes oxidative polymerization and composites with graphene and carbon black, and automatically adheres to the surface of the black talc powder through the electrostatic adsorption of KH550 to form a uniform high-conductive composite layer, and the reaction is terminated after stirring for 24 hours;

[0014] 3) The suspended reaction liquid was filtered to obtain wet powder, and the wet powder was dried in an oven at 70° C. for 10 hours to obtain a highly conductive composite system coated black talcum powder.

[0015] Furthermore, in the preparation method, in step 1), the amount of iodine added is: 10.0 g iodine per 1.0 kg black talc, and the amount of silane coupling agent KH550 added is: 15.0 g KH550 per 1.0 kg black talc;

[0016] In step 2), the amount of tris(hydroxymethyl)aminomethane-hydrochloric acid buffer added is: 5.0L tris(hydroxymethyl)aminomethane-hydrochloric acid buffer added for every 1.0kg of black talc, the amount of dopamine hydrochloride added is: 100.0g dopamine hydrochloride added for every 1.0kg of black talc, the amount of graphene added is: 30.0g graphene added for every 1.0kg dopamine hydrochloride, and the amount of carbon black added is: 20.0g carbon black added for every 1.0kg dopamine hydrochloride.

[0017] Furthermore, the dispersant is any one of stearic acid, calcium stearate, and zinc stearate.

[0018] Furthermore, the main antioxidant is a high temperature resistant hindered phenol antioxidant 1330, whose chemical name is: 1,3,5-trimethyl-2,4,6-(3,5-di-tert-butyl-4-hydroxybenzyl)benzene, and the auxiliary antioxidant is a high temperature resistant phosphite antioxidant S-8228 (manufactured by Doverphos, USA), whose chemical name is: bis(2,4-dicumylphenyl)pentaerythritol diphosphite.

[0019] A method for preparing a high electrical and thermal conductive reinforced polyphenylene sulfide composite filled with black talc, the method comprising the following steps:

[0020] (1) PPS resin, high conductive composite system coated black talcum powder, FeCl 3 Powder, dispersant, main and auxiliary antioxidants are put into a high-speed mixer and mixed evenly for use;

[0021] (2) adding the premix prepared in step (1) into a twin-screw extruder through a hopper for melt blending and extrusion, water cooling, strip drawing, pelletizing, drying and bagging, thereby obtaining the highly conductive and thermally conductive reinforced polyphenylene sulfide composite filled with black talcum powder; the temperature of each section from the barrel to the die of the twin-screw extruder is controlled at 260-320° C., and the screw speed is 300-350 rpm.

[0022] The beneficial effects of the technical solution of the present invention are:

[0023] (1) Black talc is a new type of talc-like layered magnesium silicate ore unique to my country, and is widely distributed in Jiangxi, Hunan, Chongqing, Gansu and other provinces in my country. Black talc can partially replace traditional talc for plastic filling and modification due to its similar chemical composition and layered structure to talc, and can effectively enhance the rigidity, surface hardness, tensile and bending strength, heat resistance and dimensional stability of thermoplastics, and its mining and production costs are much lower than those of traditional talc. Therefore, it has good application prospects. The present invention makes full use of the structural characteristics of the conductive graphite layer between the layers of black talc. First, iodine is used as an electron donor and acceptor to perform gas phase doping on black talc by high-temperature and high-speed stirring in a closed chamber, so that the graphite layer obtains more conductive carriers; then, dopamine hydrochloride is in-situ composited with graphene and carbon black, and self-assembled and in-situ oxidative polymerization are performed through the electrostatic attraction of the aminosilane coupling agent on the surface of black talc, so as to form a highly conductive composite coating layer of polydopamine / graphene / carbon black on the surface of black talc. In the coating layer, two-dimensional graphene flakes and three-dimensional irregular spherical carbon black are interspersed in the polydopamine matrix, which can generate multi-channel electron transmission paths, and the hydrochloric acid dopamine monomer will also penetrate into the graphite layers of the black talc powder, and form a polydopamine-based conductive composite intercalation structure with the iodine-doped graphite layer, thereby forming an electron path between the graphite layer between the black talc powder layers and its outer coating layer. This ingenious design significantly improves the electrical and thermal conductivity of the black talc powder. Through the technology of the present invention, the black talc powder is upgraded from a general traditional inorganic filler to a high-end functional filler with an enhanced electrical and thermal conductivity effect, thereby improving the product added value of the black talc powder and making an important contribution to the development and application of my country's black talc powder mine.

[0024] (2) Utilizing the rigidity enhancement and crystallization modification effects of black talcum powder, and utilizing the conductive function of its own interlayer graphite, the conductive function of the graphite layer between them is fully utilized by the high conductive composite system of the present invention for its inner intercalation layer outer coating technology. The high conductive composite system coated black talcum powder of the present invention is applied to the filling and modification of PPS special engineering plastics, which can not only play the role of traditional talcum powder in strengthening and rigidity enhancement, improving surface hardness, improving dimensional stability and warpage resistance, but also utilize the electronic pathway constructed by the black talcum powder itself, so that electrons can flow freely within the high conductive composite system coated black talcum powder layer, between layers and between powder particles, thereby producing a good conductivity and thermal conductivity modification effect on PPS. In addition, polydopamine has natural adhesion. When the coated black talcum powder is used to fill and modify PPS, the interface adhesion between the black talcum powder and the PPS matrix can be enhanced, thereby more effectively improving the mechanical properties of the filled and modified PPS. Therefore, the technology of the present invention greatly expands the filling and modification functions and effects of black talcum powder, and achieves two goals at one stroke when filling and modifying PPS.

[0025] (3) Taking full advantage of the property of PPS itself to become a conductive polymer by doping, in the process of preparing black talc-filled modified PPS, a small amount of FeCl 3 As an electron acceptor dopant, it provides more electron carriers for the black talc-filled modified PPS composite system, thereby exerting a synergistic enhancement effect of conductivity with the high-conductivity composite system coated with black talc, further improving the electrical conductivity and thermal conductivity of the composite system.

[0026] (4) A modified processing formula was designed to help disperse the inorganic filler and enhance the thermal stability of PPS, so that the inorganic powder can achieve excellent dispersion effect in the resin matrix and avoid the thermal decomposition of PPS caused by high-temperature thermomechanical friction during the twin-screw melt extrusion process, thereby enabling the prepared PPS composite to obtain better functional filling modification effect.

[0027] (5) Compared with the conventional talc-filled modified PPS composite material, the highly conductive and thermally conductive reinforced PPS composite material of the present invention has high conductivity and high thermal conductivity without the need to add other functional fillers or modifiers, and can effectively avoid the loss of mechanical properties of the composite material caused by other modifying agents.

[0028] (6) The highly conductive and thermally conductive enhanced PPS compound prepared by the present invention can not only be directly applied to injection molding of products, but also can be flexibly prepared according to different performance requirements of customers by combining various modification additives and their ratio with resin raw materials to adjust its performance and cost, quickly and easily achieve product target requirements, and practice the optimization design concept of plastic modification formula and processing technology. DETAILED DESCRIPTION

[0029] The following embodiments may enable those skilled in the art to more fully understand the present invention, but these embodiments are not intended to limit the scope of protection of the present invention. The "one embodiment" or "embodiment" referred to herein refers to a specific feature, structure or characteristic that may be included in at least one implementation of the present invention. The "in one embodiment" that appears in different places in this specification does not refer to the same embodiment, nor is it a separate or selective embodiment that is mutually exclusive with other embodiments.

[0030] Example 1

[0031] A highly conductive and thermally conductive reinforced polyphenylene sulfide (PPS) compound filled with black talc, the raw material mass ratio is as follows:

[0032]

[0033]

[0034] The preparation method of the high conductive composite system coated with black talc used in the high conductive and thermal conductive enhanced PPS composite filled with black talc is as follows:

[0035] (1) 20.0 kg of black talcum powder and 200.0 g of iodine were put into a high-speed mixer and mixed at high speed for 20 minutes in a closed environment until the material temperature rose to 80° C., then the stirring was stopped and the material was allowed to stand until the material temperature dropped to room temperature, and then 300.0 g of silane coupling agent KH-550 was added and mixed at high speed for another 10 minutes. The stirring was stopped and the material was allowed to stand until the material temperature dropped to room temperature and then taken out.

[0036] (2) The above-mentioned iodine-doped and KH-550 surface-treated black talc powder was dispersed in 100.0 L of tris(hydroxymethyl)aminomethane-hydrochloride buffer (pH = 8.4), and 2.0 kg of dopamine hydrochloride, 600.0 g of graphene and 400.0 g of

[0037] Carbon black is mechanically stirred at room temperature, during which dopamine hydrochloride will gradually undergo oxidative polymerization and compound with graphene and carbon black, and automatically adhere to the surface of black talcum powder through the electrostatic adsorption of KH550 to form a uniform high-conductive composite layer. The reaction is terminated after stirring for 24 hours;

[0038] (3) The suspended reaction liquid was filtered, washed five times with deionized water, and then filtered to obtain a wet powder, and the wet powder was dried in an oven at 70° C. for 10 hours to obtain a highly conductive composite system coated black talc powder.

[0039] The preparation method of the above-mentioned black talc-filled high electrical and thermal conductivity enhanced PPS composite is as follows:

[0040] (1) PPS resin, high conductive composite system coated black talcum powder, FeCl 3 Powder, zinc stearate, antioxidant 1330 and antioxidant S-8228 are put into a high-speed (rotation speed is 1500 rpm) mixer and mixed evenly for use;

[0041] (2) adding the premix prepared in step (1) into a twin-screw extruder through a hopper for melt blending and extrusion, water cooling, strip drawing, pelletizing, drying and bagging, thereby obtaining the high electrical and thermal conductivity enhanced PPS composite filled with black talcum powder; the temperature of each section from the barrel to the die of the twin-screw extruder is set to 260, 295, 305, 310, 320, 320, 310° C., and the screw speed is 340 rpm.

[0042] Example 2

[0043] A highly conductive and thermally conductive reinforced polyphenylene sulfide (PPS) compound filled with black talc, the raw material mass ratio is as follows:

[0044]

[0045]

[0046] The preparation method of the high conductive composite system coated with black talc used in the high conductive and thermal conductive enhanced PPS composite filled with black talc is as follows:

[0047] (1) 20.0 kg of black talcum powder and 200.0 g of iodine were put into a high-speed mixer and mixed at high speed for 20 minutes in a closed environment until the material temperature rose to 80° C., then the stirring was stopped and the material was allowed to stand until the material temperature dropped to room temperature, and then 300.0 g of silane coupling agent KH-550 was added and mixed at high speed for another 10 minutes. The stirring was stopped and the material was allowed to stand until the material temperature dropped to room temperature and then taken out.

[0048] (2) The above-mentioned iodine-doped and KH-550 surface-treated black talc powder was dispersed in 100.0 L of tris(hydroxymethyl)aminomethane-hydrochloride buffer (pH = 8.4), and 2.0 kg of dopamine hydrochloride, 600.0 g of graphene and 400.0 g of

[0049] Carbon black is mechanically stirred at room temperature, during which dopamine hydrochloride will gradually undergo oxidative polymerization and compound with graphene and carbon black, and automatically adhere to the surface of black talcum powder through the electrostatic adsorption of KH550 to form a uniform high-conductive composite layer. The reaction is terminated after stirring for 24 hours;

[0050] (3) The suspended reaction liquid was filtered, washed five times with deionized water, and then filtered to obtain a wet powder, and the wet powder was dried in an oven at 70° C. for 10 hours to obtain a highly conductive composite system coated black talc powder.

[0051] The preparation method of the above-mentioned black talc-filled high electrical and thermal conductivity enhanced PPS composite is as follows:

[0052] (1) PPS resin, high conductive composite system coated black talcum powder, FeCl 3 Powder, stearic acid, antioxidant 1330 and antioxidant S-8228 are put into a high-speed (rotation speed is 1500 rpm) mixer and mixed evenly for use;

[0053] (2) adding the premix prepared in step (1) into a twin-screw extruder through a hopper for melt blending and extrusion, water cooling, strip drawing, pelletizing, drying and bagging, thereby obtaining the high electrical and thermal conductivity enhanced PPS composite filled with black talcum powder; the temperature of each section from the barrel to the die of the twin-screw extruder is set to 265, 300, 305, 315, 320, 315, 315° C., and the screw speed is 310 rpm.

[0054] Example 3

[0055] A highly conductive and thermally conductive reinforced polyphenylene sulfide (PPS) compound filled with black talc, the raw material mass ratio is as follows:

[0056]

[0057]

[0058] The preparation method of the high conductive composite system coated with black talc used in the high conductive and thermal conductive enhanced PPS composite filled with black talc is as follows:

[0059] (1) 20.0 kg of black talcum powder and 200.0 g of iodine were put into a high-speed mixer and mixed at high speed for 20 minutes in a closed environment until the material temperature rose to 80° C., then the stirring was stopped and the material was allowed to stand until the material temperature dropped to room temperature, and then 300.0 g of silane coupling agent KH-550 was added and mixed at high speed for another 10 minutes. The stirring was stopped and the material was allowed to stand until the material temperature dropped to room temperature and then taken out.

[0060] (2) The above-mentioned iodine-doped and KH-550 surface-treated black talc powder was dispersed in 100.0 L of tris(hydroxymethyl)aminomethane-hydrochloride buffer (pH = 8.4), and 2.0 kg of dopamine hydrochloride, 600.0 g of graphene and 400.0 g of

[0061] Carbon black is mechanically stirred at room temperature, during which dopamine hydrochloride will gradually undergo oxidative polymerization and compound with graphene and carbon black, and automatically adhere to the surface of black talcum powder through the electrostatic adsorption of KH550 to form a uniform high-conductive composite layer. The reaction is terminated after stirring for 24 hours;

[0062] (3) The suspended reaction liquid was filtered, washed five times with deionized water, and then filtered to obtain a wet powder, and the wet powder was dried in an oven at 70° C. for 10 hours to obtain a highly conductive composite system coated black talc powder.

[0063] The preparation method of the above-mentioned black talc-filled high electrical and thermal conductivity enhanced PPS composite is as follows:

[0064] (1) PPS resin, high conductive composite system coated black talcum powder, FeCl 3 Powder, calcium stearate, antioxidant 1330 and antioxidant S-8228 are put into a high-speed (rotation speed is 1500 rpm) mixer and mixed evenly for use;

[0065] (2) adding the premix prepared in step (1) into a twin-screw extruder through a hopper for melt blending and extrusion, water cooling, strip drawing, pelletizing, drying and bagging, thereby obtaining the black talcum powder filled high electrical and thermal conductivity enhanced PPS composite; the temperature of each section from the barrel to the die of the twin-screw extruder is set to 263, 300, 305, 315, 320, 315, 315 ° C, and the screw speed is 350 rpm.

[0066] Example 4

[0067] A highly conductive and thermally conductive reinforced polyphenylene sulfide (PPS) compound filled with black talc, the raw material mass ratio is as follows:

[0068]

[0069]

[0070] The preparation method of the high conductive composite system coated with black talc used in the high conductive and thermal conductive enhanced PPS composite filled with black talc is as follows:

[0071] (1) 20.0 kg of black talcum powder and 200.0 g of iodine were put into a high-speed mixer and mixed at high speed for 20 minutes in a closed environment until the material temperature rose to 80° C., then the stirring was stopped and the material was allowed to stand until the material temperature dropped to room temperature, and then 300.0 g of silane coupling agent KH-550 was added and mixed at high speed for another 10 minutes. The stirring was stopped and the material was allowed to stand until the material temperature dropped to room temperature and then taken out.

[0072] (2) The above-mentioned iodine-doped and KH-550 surface-treated black talc powder was dispersed in 100.0 L of tris(hydroxymethyl)aminomethane-hydrochloride buffer (pH = 8.4), and 2.0 kg of dopamine hydrochloride, 600.0 g of graphene and 400.0 g of

[0073] Carbon black is mechanically stirred at room temperature, during which dopamine hydrochloride will gradually undergo oxidative polymerization and compound with graphene and carbon black, and automatically adhere to the surface of black talcum powder through the electrostatic adsorption of KH550 to form a uniform high-conductive composite layer. The reaction is terminated after stirring for 24 hours;

[0074] (3) The suspended reaction liquid was filtered, washed five times with deionized water, and then filtered to obtain a wet powder, and the wet powder was dried in an oven at 70° C. for 10 hours to obtain a highly conductive composite system coated black talc powder.

[0075] The preparation method of the above-mentioned black talc-filled high electrical and thermal conductivity enhanced PPS composite is as follows:

[0076] (1) PPS resin, high conductive composite system coated black talcum powder, FeCl 3 Powder, zinc stearate, antioxidant 1330 and antioxidant S-8228 are put into a high-speed (rotation speed is 1500 rpm) mixer and mixed evenly for use;

[0077] (2) adding the premix prepared in step (1) into a twin-screw extruder through a hopper for melt blending and extrusion, water cooling, strip drawing, pelletizing, drying and bagging, thereby obtaining the high electrical and thermal conductivity enhanced PPS composite filled with black talcum powder; the temperature of each section from the barrel to the die of the twin-screw extruder is set to 260, 302, 308, 315, 320, 320, 315° C., and the screw speed is 330 rpm.

[0078] Example 5

[0079] A highly conductive and thermally conductive reinforced polyphenylene sulfide (PPS) compound filled with black talc, the raw material mass ratio is as follows:

[0080]

[0081]

[0082] The preparation method of the high conductive composite system coated with black talc used in the high conductive and thermal conductive enhanced PPS composite filled with black talc is as follows:

[0083] (1) 20.0 kg of black talcum powder and 200.0 g of iodine were put into a high-speed mixer and mixed at high speed for 20 minutes in a closed environment until the material temperature rose to 80° C., then the stirring was stopped and the material was allowed to stand until the material temperature dropped to room temperature, and then 300.0 g of silane coupling agent KH-550 was added and mixed at high speed for another 10 minutes. The stirring was stopped and the material was allowed to stand until the material temperature dropped to room temperature and then taken out.

[0084] (2) The above-mentioned iodine-doped and KH-550 surface-treated black talc powder was dispersed in 100.0L tris(hydroxymethylaminomethane)-hydrochloride buffer (pH=8.4), and 2.0kg dopamine hydrochloride, 600.0g graphene and 400.0g carbon black were added in sequence, and mechanical stirring was performed at room temperature, during which the dopamine hydrochloride gradually underwent oxidative polymerization and composited with graphene and carbon black, and automatically adhered to the surface of the black talc powder through the electrostatic adsorption of KH550 to form a uniform high-conductive composite layer, and the reaction was terminated after stirring for 24 hours;

[0085] (3) The suspended reaction liquid was filtered, washed five times with deionized water, and then filtered to obtain a wet powder, and the wet powder was dried in an oven at 70° C. for 10 hours to obtain a highly conductive composite system coated black talc powder.

[0086] The preparation method of the above-mentioned black talc-filled high electrical and thermal conductivity enhanced PPS composite is as follows:

[0087] (1) PPS resin, high conductive composite system coated black talcum powder, FeCl 3 Powder, calcium stearate, primary and secondary antioxidants are put into a high-speed (rotation speed is 1500 rpm) mixer and mixed evenly for use;

[0088] (2) adding the premix prepared in step (1) into a twin-screw extruder through a hopper for melt blending and extrusion, water cooling, strip drawing, pelletizing, drying and bagging, thereby obtaining the high electrical and thermal conductivity enhanced PPS composite filled with black talcum powder; the temperature of each section from the barrel to the die of the twin-screw extruder is set to 263, 306, 309, 313, 320, 318, and 312° C., and the screw speed is 300 rpm.

[0089] Example 6

[0090] A highly conductive and thermally conductive reinforced polyphenylene sulfide (PPS) compound filled with black talc, the raw material mass ratio is as follows:

[0091]

[0092]

[0093] The preparation method of the high conductive composite system coated with black talc used in the high conductive and thermal conductive enhanced PPS composite filled with black talc is as follows:

[0094] (1) 20.0 kg of black talcum powder and 200.0 g of iodine were put into a high-speed mixer and mixed at high speed for 20 minutes in a closed environment until the material temperature rose to 80° C., then the stirring was stopped and the material was allowed to stand until the material temperature dropped to room temperature, and then 300.0 g of silane coupling agent KH-550 was added and mixed at high speed for another 10 minutes. The stirring was stopped and the material was allowed to stand until the material temperature dropped to room temperature and then taken out.

[0095] (2) The above-mentioned iodine-doped and KH-550 surface-treated black talc powder was dispersed in 100.0 L of tris(hydroxymethyl)aminomethane-hydrochloride buffer (pH = 8.4), and 2.0 kg of dopamine hydrochloride, 600.0 g of graphene and 400.0 g of

[0096] Carbon black is mechanically stirred at room temperature, during which dopamine hydrochloride will gradually undergo oxidative polymerization and compound with graphene and carbon black, and automatically adhere to the surface of black talcum powder through the electrostatic adsorption of KH550 to form a uniform high-conductive composite layer. The reaction is terminated after stirring for 24 hours;

[0097] (3) The suspended reaction liquid was filtered, washed five times with deionized water, and then filtered to obtain a wet powder, and the wet powder was dried in an oven at 70° C. for 10 hours to obtain a highly conductive composite system coated black talc powder.

[0098] The preparation method of the above-mentioned black talc-filled high electrical and thermal conductivity enhanced PPS composite is as follows:

[0099] (1) PPS resin, high conductive composite system coated black talcum powder, FeCl 3 Powder, stearic acid, antioxidant 1330 and antioxidant S-8228 are put into a high-speed (rotation speed is 1500 rpm) mixer and mixed evenly for use;

[0100] (2) adding the premix prepared in step (1) into a twin-screw extruder through a hopper for melt blending and extrusion, water cooling, strip drawing, pelletizing, drying and bagging, thereby obtaining the high electrical and thermal conductivity enhanced PPS composite filled with black talcum powder; the temperature of each section from the barrel to the die of the twin-screw extruder is set to 261, 307, 312, 318, 320, 315, and 310° C., and the screw speed is 320 rpm.

[0101] In order to verify the modification effect of the highly conductive and thermally conductive reinforced PPS composite based on the high conductive composite system coated with black talcum powder filled prepared by the present invention, the highly conductive and thermally conductive reinforced PPS composite prepared in Examples 1-6 was injection molded into tensile, bending, conductive, and thermally conductive test specimens according to the corresponding national standards for plastic testing, and then the tensile strength and tensile modulus were tested according to GB / T1040.2-2006, the bending strength and bending modulus were tested according to GB / T1449-2005, the bending strength and bending modulus were tested according to GB / T1449-2005, the volume conductivity was tested according to GB / T15662-1995, and the thermal conductivity was tested according to GB / T42919.1-2006. At the same time, the same performance test was carried out on the pure PPS resin control example. All performance test results are shown in Table 1. Table 1 Comparison table of various properties of the highly conductive and thermally conductive reinforced PPS composite based on the highly conductive composite system coated with black talcum powder filled prepared in Examples 1-6 and the pure PPS resin of the control example

[0102]

[0103] By reference to the data in Table 1, it is shown that the tensile strength, tensile modulus, flexural strength, flexural modulus, and thermal conductivity of the highly conductive and thermally conductive enhanced PPS composite based on the high conductive composite system coated with black talcum powder filled prepared in the embodiment of the present invention are significantly improved compared with pure PPS resin, while the resistivity is significantly reduced. It can be seen that the use of the conductive and thermally conductive enhanced PPS composite of the present invention not only effectively improves the strength and modulus of the PPS resin, but also gives the PPS resin excellent electrical conductivity and thermal conductivity. This modification effect is completely unattainable by the traditional talcum powder filled modified PPS resin.

[0104] With the above-mentioned ideal embodiments of the present invention as inspiration, through the above-mentioned description, relevant staff can make various changes and modifications without departing from the technical idea of ​​the present invention. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention. The technical scope of the present invention is not limited to the contents of the specification, and its technical scope must be determined according to the scope of the claims.

Claims

1. A highly conductive and thermally conductive reinforced polyphenylene sulfide composite filled with black talcum powder, characterized in that: The mass percentage composition of the PPS composite is as follows: PPS resin 75.0~86.0 wt.%, Highly conductive composite system coated with black talcum powder 10.0~21.0 wt.% Ferric chloride powder 1.0~3.0 wt.%, Dispersant 0.5~1.0 wt.%, Main antioxidant 0.1~0.15 wt.%, Auxiliary antioxidant 0.1~0.15 wt.%; The highly conductive composite system coated black talc is an iodine-doped electron acceptor-doped black talc in situ coated with polydopamine, graphene and carbon black; The preparation method of the highly conductive composite system coated with black talcum powder is as follows: 1) Add black talcum powder and iodine into a high-speed mixer according to the ratio, mix at high speed for 20 minutes in a closed environment, raise the material temperature to 80°C, then stop stirring, let it stand until the material temperature drops to room temperature, then add silane coupling agent KH-550, mix at high speed for 10 minutes again, stop stirring, let it stand until the material temperature drops to room temperature and take it out; 2) The iodine-doped and KH-550-surface-treated black talc powder was dispersed in tris(hydroxymethylaminomethane)-hydrochloride buffer (pH=8.4), and dopamine hydrochloride, graphene and carbon black were added in sequence. The mixture was mechanically stirred at room temperature, during which the dopamine hydrochloride gradually underwent oxidative polymerization and composited with graphene and carbon black. The dopamine hydrochloride was automatically adhered to the surface of the black talc powder through the electrostatic adsorption of KH550 to form a uniform highly conductive composite layer. The reaction was terminated after stirring for 24 hours to obtain a suspended reaction liquid. 3) filtering the above-mentioned suspended reaction liquid to obtain wet powder, and drying the wet powder in an oven at 70° C. for 10 hours to obtain a highly conductive composite system coated black talc powder; In the preparation method, the amount of iodine added in step 1) is: 10.0 g iodine is added for every 1.0 kg black talc powder, and the amount of silane coupling agent KH550 is: 15.0 g KH550 is added for every 1.0 kg black talc powder; In step 2), the amount of tris(hydroxymethyl)aminomethane-hydrochloric acid buffer added is: 5.0L tris(hydroxymethyl)aminomethane-hydrochloric acid buffer added for every 1.0kg black talcum powder, the amount of dopamine hydrochloride added is: 100.0g dopamine hydrochloride added for every 1.0kg black talcum powder, the amount of graphene added is: 30.0g graphene added for every 1.0kg dopamine hydrochloride, and the amount of carbon black added is: 20.0g carbon black added for every 1.0kg dopamine hydrochloride.

2. The high electrical and thermal conductivity enhanced polyphenylene sulfide composite filled with black talc according to claim 1, characterized in that: The dispersant is any one of stearic acid, calcium stearate and zinc stearate.

3. The black talc-filled, highly conductive and thermally conductive enhanced polyphenylene sulfide composite according to claim 1, characterized in that: The main antioxidant is a high temperature resistant hindered phenol antioxidant 1330, and the auxiliary antioxidant is a high temperature resistant phosphite antioxidant S-8228.

4. A method for preparing a black talc-filled, highly conductive and thermally conductive reinforced polyphenylene sulfide composite as claimed in any one of claims 1 to 3, characterized in that: The method comprises the following steps: (1) PPS resin, high-conductivity composite system coated black talcum powder, FeCl3 powder, dispersant, primary and secondary antioxidants are weighed according to the proportion, and put into a high-speed mixer to mix evenly and set aside; (2) adding the premix prepared in step (1) into a twin-screw extruder through a hopper for melt blending and extrusion, water cooling, strip drawing, pelletizing, drying and bagging, thereby obtaining the highly conductive and thermally conductive reinforced polyphenylene sulfide composite filled with black talcum powder; the temperature of each section from the barrel to the die of the twin-screw extruder is controlled at 260 to 320° C., and the screw speed is 300 to 350 rpm.

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