A plastic-steel PPS composite material and its preparation process

Abstract

The present application relates to the technical field of preparing plastic-steel composite materials for new energy vehicles, in particular to a plastic-steel PPS composite material and its preparation process. A plastic-steel PPS composite material comprises a modified PPS matrix resin and at least one aramid fiber-based woven fabric compounded within the modified PPS matrix resin, wherein the aramid fiber-based woven fabric is a warp-weft knitted structure of a plain weave, wherein the warp threads in the aramid fiber-based woven fabric at least include aramid fibers, and the weft threads at least include aramid fibers; the modified PPS matrix resin comprises the following raw materials in parts by weight: 100 parts of PPS resin, 5-20 parts of hyperbranched PPS resin, 50-70 parts of a filler composition, 0.5-2 parts of a dispersant, and 1-3 parts of an anti-aging agent. The present application has good thermal stability, chemical corrosion resistance, electrical properties, wear resistance and flame retardancy, while also having good impact toughness and mechanical strength, and can meet the use requirements of battery casing materials.

Description

Technical Field

[0001] The present application relates to the technical field of preparation of plastic-steel composite materials for new energy vehicles, and in particular to a plastic-steel PPS composite material and its preparation process. Background Art

[0002] Polyphenylene sulfide (PPS) boasts excellent mechanical properties, thermal stability, chemical resistance, electrical properties, wear resistance, and flame retardancy, and has been used in lithium batteries, lightweight vehicles, aviation materials, and wastewater organic matter treatment. Currently, PPS is widely used in automotive parts such as igniters, connectors, thermostats, IGBT modules, heater vent brackets, and generator coil bobbins. With the rapid development of new energy vehicles, PPS is finding application in peripheral components for NEV drive motors and power batteries. For example, the lithium battery brackets in some high-end models are made of PPS composite materials.

[0003] Due to the shortcomings of high crystallinity and brittleness of polyphenylene sulfide, it is impossible to prepare high-toughness polyphenylene sulfide products. At the same time, the high melting point of polyphenylene sulfide reduces its fluidity during melt processing, resulting in deviations in the overall processing performance and the inability to produce and process special-shaped structural parts around new energy vehicle drive motors and power batteries.

[0004] For example, the battery casing of lithium batteries used to be made of 304 or 306 stainless steel, which has good rust and corrosion resistance. With the increasing demand for lightweight vehicles, rust and corrosion resistant 3003 aluminum alloy materials have gradually replaced 304 or 306 stainless steel as battery casings for lithium batteries, providing good protection and support for lithium battery modules. The density of 3003 aluminum alloy material is 2.70±0.02g / cm 3 , tensile strength σ b The yield strength is 140-180MPa, and the conditional yield strength σ0.2≥85MPa. It has good plasticity and anti-rust and corrosion properties, making it suitable for battery shell materials.

[0005] With the increasing demand for lightweight vehicles, automakers are looking for a high-performance polymer plastic-steel composite material to replace 3003 aluminum alloy battery casing materials. The excellent performance of polyphenylene sulfide has attracted the attention of the new energy industry: the density of the currently publicized 40wt% GF modified polyphenylene sulfide material is 1.55-1.72 g / cm 3, it has good lightweight advantages and its tensile properties also meet the requirements. Its tensile strength is 135-220 MPa and its flexural strength is 200-300 MPa. However, its strength is relatively high and its impact toughness is biased. As a battery shell, it is easily brittle and cracked by external impact. Its protective performance is questioned, which limits its application in new energy vehicle battery modules. In summary, although the existing high-performance polyphenylene sulfide composite materials have the advantages of lightweight and mechanical strength in the field of lithium batteries for new energy vehicles, their impact toughness is relatively general and cannot meet the protection requirements of battery shell materials. To this end, the present application provides a plastic-steel PPS composite material and a preparation process thereof. Summary of the Invention

[0006] In order to solve the above-mentioned problems in the prior art, the present application provides a plastic-steel PPS composite material and a preparation process thereof.

[0007] The plastic-steel PPS composite material provided in this application is realized through the following technical solutions:

[0008] A plastic-steel PPS composite material, comprising a modified PPS matrix resin and at least one aramid fiber-based woven fabric composited within the modified PPS matrix resin, wherein the aramid fiber-based woven fabric has a plain weave structure of warp and weft, wherein the warp yarns of the aramid fiber-based woven fabric at least comprise aramid fibers, and the weft yarns at least comprise aramid fibers;

[0009] The modified PPS matrix resin is made of the following raw materials in parts by mass: 100 parts of PPS resin, 5-20 parts of hyperbranched PPS resin, 50-70 parts of filler composition, 0.5-2 parts of dispersant, and 1-3 parts of anti-aging agent;

[0010] The dispersant is at least one of stearate, siloxane coupling agent and titanate coupling agent;

[0011] The anti-aging agent is at least one of antioxidant 1024, antioxidant 4426, antioxidant 300, antioxidant 168, and antioxidant 626;

[0012] The filler composition comprises a combination of spherical fillers, fibrous fillers and flake fillers.

[0013] The spherical filler includes at least one of spherical alumina, spherical aluminum nitride, spherical silicon dioxide, spherical silicon nitride, spherical titanium nitride, and spherical silicon carbide;

[0014] The fibrous filler comprises at least one of nano-carbon fibers, chopped aramid fiber compositions, carbon nanotubes, cellulose nanofibers, and inorganic whiskers;

[0015] The inorganic whiskers include at least one of zinc oxide whiskers, aluminum oxide whiskers, zirconium oxide, aluminum nitride whiskers, boron nitride whiskers, silicon dioxide whiskers, silicon nitride whiskers, silicon carbide whiskers, calcium carbonate whiskers, and potassium titanate whiskers;

[0016] The flaky filler includes at least one of graphene nanosheets, boron nitride nanosheets, MXene phase ceramic nanosheets, ultrafine mica sheets, and molybdenum sulfide nanosheets.

[0017] The composite design of the compound filler composition and hyperbranched PPS resin combined with the built-in aramid fiber-based woven fabric in this application effectively improves the overall mechanical strength, thermal stability, chemical corrosion resistance, electrical properties, wear resistance and flame retardancy of the plastic-steel PPS composite material, and at the same time has excellent impact toughness, meeting the requirements of battery shell materials.

[0018] Preferably, the mass ratio of the spherical filler, the fibrous filler and the flake filler is (50-80):(10-30):(10-20).

[0019] The overall mechanical strength can be improved by optimizing the ratio of spherical fillers, fibrous fillers and flake fillers.

[0020] Preferably, the spherical filler is spherical alumina, spherical silicon nitride, and spherical titanium nitride in a mass ratio of (80-90):(5-10):(5-10); the spherical alumina is composed of nano-spherical alumina with an average particle size of 100-400 nm, ultrafine spherical alumina with an average particle size of 0.5-5 μm, and spherical alumina with an average particle size of 25-50 μm in a mass ratio of (15-25):(35-60):(25-40); the average particle size of the spherical silicon nitride is 0.8-5 μm; and the average particle size of the spherical titanium nitride is 0.02-5 μm.

[0021] Preferably, the fibrous filler is composed of a chopped aramid fiber composition, single-walled carbon nanotubes, zinc oxide whiskers, and potassium titanate whiskers; the mass ratio of the chopped aramid fiber composition, single-walled carbon nanotubes, zinc oxide whiskers, and potassium titanate whiskers is (40-73):(25-50):(1-5):(1-5).

[0022] Preferably, the flaky filler is composed of molybdenum sulfide nanosheets, boron nitride nanosheets, and ultrafine mica sheets; the mass ratio of the molybdenum sulfide nanosheets, boron nitride nanosheets, and ultrafine mica sheets is (5-20):(5-20):(60-90).

[0023] By adopting the above technical solution, the overall mechanical strength can be further improved, and it is also beneficial to enhance the impact toughness, thermal stability, chemical corrosion resistance, electrical properties, wear resistance and flame retardancy.

[0024] Preferably, the ultrafine mica sheet is a surface carbon nanotube grafted modified mica sheet and / or a surface graphene grafted modified mica sheet; the surface carbon nanotube grafted modified mica sheet includes an ultrafine mica sheet carrier with a particle size of ≤1250 mesh and carbon nanotubes fixed to the ultrafine mica sheet carrier with a particle size of ≤1250 mesh by nanosilver sintering; the surface graphene grafted modified mica sheet includes an ultrafine mica sheet carrier with a particle size of ≤1250 mesh and graphene nanosheets fixed to the ultrafine mica sheet carrier with a particle size of ≤1250 mesh by nanosilver sintering.

[0025] By adopting the above technical solution, the overall mechanical strength and insulation and thermal conductivity can be further improved.

[0026] Preferably, the mass ratio of the spherical filler, the fibrous filler and the flaky filler is (55-60):(20-25):(15-20); the dispersant is composed of KH-550 silane coupling agent, KH-570 silane coupling agent and titanate coupling agent HY-311 in a mass ratio of (0.5-2):(0.5-2):(0.1-0.4).

[0027] By adopting the above technical solution, the overall mechanical strength and impact toughness can be further improved.

[0028] Preferably, the aramid fiber-based woven fabric is a plain weave warp-weft structure, with the spacing between adjacent warps being 0.5-2 mm; the spacing between adjacent wefts being 0.5-2 mm; the warps in the aramid fiber-based woven fabric include aramid fiber filaments and carbon fiber filaments arranged at intervals from each other; and the wefts in the aramid fiber-based woven fabric include aramid fiber filaments and carbon fiber filaments arranged at intervals from each other.

[0029] Preferably, the aramid fiber-based woven fabric needs to undergo a surface modification process before use; the surface modification process of the aramid fiber-based woven fabric is as follows:

[0030] Step 1: The aramid fiber-based woven fabric is ultrasonically cleaned in an ethanol-water solution, then rinsed with clean water, dried, and set aside;

[0031] Step 2: treating the aramid fiber-based woven fabric with low-temperature plasma, first with ozone at 0-4°C for 60-300s, and then with ammonia at 0-4°C for 60-300s, to obtain a semi-finished aramid fiber-based woven fabric;

[0032] Step three, placing the aramid fiber-based woven fabric that has completed the low-temperature plasma treatment in a methacryloxysilane aqueous solution, heating it to 45-50°C and performing ultrasonic dispersion treatment for 20-40 minutes, wherein the methacryloxysilane concentration in the methacryloxysilane aqueous solution is 4-8wt%. After completing the ultrasonic dispersion treatment, the aramid fiber-based woven fabric is taken out, drained, and then dried to obtain the finished aramid fiber-based woven fabric.

[0033] By adopting the above technical solution, the interfacial compatibility between aramid fiber-based woven fabrics and modified PPS matrix resins is improved, which is beneficial to the improvement of mechanical strength, impact toughness, thermal stability, chemical corrosion resistance, electrical properties, wear resistance and flame retardancy.

[0034] The preparation process of a plastic-steel PPS composite material provided in this application is achieved through the following technical solutions:

[0035] A preparation process of a plastic-steel PPS composite material comprises the following steps:

[0036] Step 1: first prepare a filler composition, and then perform surface modification on the prepared filler composition: the filler composition is placed in a surface modification liquid and subjected to ultrasonic dispersion treatment for 20-40 minutes, then drained and dried to obtain a finished filler composition; the surface modification liquid is composed of a surface modifier and deionized water, and the surface modifier is a siloxane coupling agent and / or a titanate coupling agent;

[0037] At the same time, the aramid fiber-based woven fabric is subjected to a surface modification process to obtain a finished aramid fiber-based woven fabric;

[0038] Step 2: The filler composition in step 1 is mixed and dispersed uniformly with the correctly measured PPS resin, hyperbranched PPS resin, dispersant, and anti-aging agent at high speed, and then fed into a twin-screw extruder. The mixture is melt-extruded at a barrel end temperature of 285-325° C., subjected to wire drawing, nitrogen cooling, granulation, and drying to obtain a PPS composite masterbatch.

[0039] Step 3: using PPS composite masterbatch for injection molding to form a PPS sheet with a thickness of 0.25-0.40 mm;

[0040] Step 4: stack to form a PPS sheet / finished aramid fiber-based woven fabric / PPS sheet structure, hot press at 280-300°C and 5-15MPa for 5-15min to obtain a PPS composite sheet, heat treat the obtained PPS composite sheet at 140-160°C for 30-60min, and naturally cool to room temperature to obtain a plastic-steel PPS composite sheet that meets the use requirements of battery casing materials.

[0041] The preparation process of the present application improves the processing performance of PPS and the implementation scheme is relatively simple, which facilitates industrial production.

[0042] In summary, this application has the following advantages:

[0043] 1. The composite design of the compound filler composition and hyperbranched PPS resin combined with the built-in aramid fiber-based woven fabric adopted in this application effectively improves the overall mechanical strength, thermal stability, chemical corrosion resistance, electrical properties, wear resistance and flame retardancy of the plastic-steel PPS composite material, and at the same time has excellent impact toughness, meeting the requirements of battery shell materials.

[0044] 2. In this application, the filler composition formed by optimizing the ratio of spherical fillers, fibrous fillers, and flaky fillers reduces the amount of the filler composition while ensuring the same physical and chemical properties of the plastic-steel PPS composite board, which is beneficial to reducing the overall production cost.

[0045] 3. The preparation process of the present application improves the processing performance of PPS and the implementation scheme is relatively simple, which facilitates industrial production. DETAILED DESCRIPTION

[0046] In order to further understand the present invention, preferred embodiments of the present invention are described below with reference to examples and comparative examples. Example

[0047] A plastic-steel PPS composite material includes a modified PPS matrix resin and at least one aramid fiber-based woven fabric composited within the modified PPS matrix resin. The aramid fiber-based woven fabric has a plain weave structure with warp and weft threads comprising at least aramid fibers.

[0048] The modified PPS matrix resin comprises the following raw materials in parts by mass: 100 parts of PPS resin, 5-20 parts of hyperbranched PPS resin, 50-70 parts of filler composition, 0.5-2 parts of dispersant, and 1-3 parts of anti-aging agent.

[0049] Preferably, the modified PPS matrix resin comprises the following raw materials in parts by mass: 100 parts of PPS resin, 15 parts of hyperbranched PPS resin, 65 parts of filler composition, 2 parts of dispersant, and 3 parts of anti-aging agent.

[0050] The dispersant is at least one of stearate, siloxane coupling agent and titanate coupling agent.

[0051] Preferably, the mass ratio of the spherical filler, the fibrous filler and the flake filler is (50-80):(10-30):(10-20).

[0052] Preferably, the mass ratio of the spherical filler, the fibrous filler and the flake filler is (55-60):(20-25):(15-20).

[0053] Preferably, the dispersant is composed of KH-550 silane coupling agent, KH-570 silane coupling agent, and titanate coupling agent HY-311 in a mass ratio of (0.5-2):(0.5-2):(0.1-0.4).

[0054] The anti-aging agent is at least one of antioxidant 1024, antioxidant 4426, antioxidant 300, antioxidant 168, and antioxidant 626. Preferably, the anti-aging agent is composed of antioxidant 1024 and antioxidant 168.

[0055] The filler composition comprises spherical fillers, fibrous fillers and flake fillers.

[0056] The spherical filler includes at least one of spherical alumina, spherical aluminum nitride, spherical silicon dioxide, spherical silicon nitride, spherical titanium nitride, and spherical silicon carbide. Preferably, the spherical filler is spherical alumina, spherical silicon nitride, and spherical titanium nitride in a mass ratio of (80-90):(5-10):(5-10). The spherical alumina is composed of nano-spherical alumina with an average particle size of 100-400nm, ultrafine spherical alumina with an average particle size of 0.5-5 μm, and spherical alumina with an average particle size of 25-50 μm in a mass ratio of (15-25):(35-60):(25-40). The average particle size of spherical silicon nitride is 0.8-5 μm. The average particle size of spherical titanium nitride is 0.02-5 μm.

[0057] The inorganic whiskers include at least one of zinc oxide whiskers, aluminum oxide whiskers, zirconium oxide, aluminum nitride whiskers, boron nitride whiskers, silicon dioxide whiskers, silicon nitride whiskers, silicon carbide whiskers, calcium carbonate whiskers, and potassium titanate whiskers. Preferably, the fibrous filler is composed of a chopped aramid fiber composition, single-walled carbon nanotubes, zinc oxide whiskers, and potassium titanate whiskers, and the mass ratio of the chopped aramid fiber composition, single-walled carbon nanotubes, zinc oxide whiskers, and potassium titanate whiskers is (40-73):(25-50):(1-5):(1-5).

[0058] The flaky filler comprises at least one of graphene nanosheets, boron nitride nanosheets, MXene-phase ceramic nanosheets, ultrafine mica flakes, and molybdenum sulfide nanosheets. Preferably, the flaky filler comprises molybdenum sulfide nanosheets, boron nitride nanosheets, and ultrafine mica flakes, and the mass ratio of molybdenum sulfide nanosheets, boron nitride nanosheets, and ultrafine mica flakes is (5-20):(5-20):(60-90).

[0059] Preferably, the ultrafine mica flakes are mica flakes modified by surface grafting of carbon nanotubes and / or surface grafting of graphene.

[0060] The surface carbon nanotube grafted modified mica sheet comprises an ultrafine mica sheet carrier with a particle size of ≤1250 meshes and carbon nanotubes fixed on the ultrafine mica sheet carrier with a particle size of ≤1250 meshes through nano-silver sintering.

[0061] The surface graphene grafted modified mica sheet comprises an ultrafine mica sheet carrier with a particle size of ≤1250 meshes and a graphene nanosheet fixed on the ultrafine mica sheet carrier with a particle size of ≤1250 meshes through nano-silver sintering.

[0062] Aramid fiber-based woven fabrics feature a plain weave structure with a warp-weft knit structure. The spacing between adjacent warp threads is 0.5-2 mm, and the spacing between adjacent weft threads is 0.5-2 mm. The warp threads in this fabric consist of aramid fiber filaments and carbon fiber filaments spaced apart from each other. The weft threads in this fabric consist of aramid fiber filaments and carbon fiber filaments spaced apart from each other.

[0063] Aramid fiber-based woven fabrics need to undergo surface modification before use.

[0064] The surface modification process of aramid fiber-based woven fabrics is as follows:

[0065] Step 1: The aramid fiber-based woven fabric is ultrasonically cleaned in an ethanol-water solution, then rinsed with clean water, dried, and set aside;

[0066] Step 2: treating the aramid fiber-based woven fabric with low-temperature plasma, first with ozone at 0-4°C for 60-300s, and then with ammonia at 0-4°C for 60-300s, to obtain a semi-finished aramid fiber-based woven fabric;

[0067] Step 3: Place the aramid fiber-based woven fabric that has completed the low-temperature plasma treatment in a methacryloxysilane aqueous solution, heat it to 45-50°C, and perform ultrasonic dispersion treatment for 20-40 minutes. The methacryloxysilane concentration in the methacryloxysilane aqueous solution is 4-8wt%. After the ultrasonic dispersion treatment, take out the aramid fiber-based woven fabric, drain it, and then dry it to obtain the finished aramid fiber-based woven fabric.

[0068] A preparation process of a plastic-steel PPS composite material comprises the following steps:

[0069] Step 1: first prepare a filler composition, and then perform surface modification on the prepared filler composition: the filler composition is placed in a surface modification liquid and subjected to ultrasonic dispersion treatment for 20-40 minutes, then drained and dried to obtain a finished filler composition; the surface modification liquid is composed of a surface modifier and deionized water, and the surface modifier is a siloxane coupling agent and / or a titanate coupling agent;

[0070] At the same time, the aramid fiber-based woven fabric is subjected to a surface modification process to obtain a finished aramid fiber-based woven fabric;

[0071] Step 2: The filler composition in step 1 is mixed and dispersed uniformly with the correctly measured PPS resin, hyperbranched PPS resin, dispersant, and anti-aging agent at high speed, and then fed into a twin-screw extruder. The mixture is melt-extruded at a barrel end temperature of 285-325° C., subjected to wire drawing, nitrogen cooling, granulation, and drying to obtain a PPS composite masterbatch.

[0072] Step 3: using PPS composite masterbatch for injection molding to form a PPS sheet with a thickness of 0.25-0.40 mm;

[0073] Step 4: stack to form a PPS sheet / finished aramid fiber-based woven fabric / PPS sheet structure, hot press at 280-300°C and 5-15MPa for 5-15min to obtain a PPS composite sheet, heat treat the obtained PPS composite sheet at 140-160°C for 30-60min, and naturally cool to room temperature to obtain a plastic-steel PPS composite sheet that meets the use requirements of battery casing materials.

[0074] Example 1: A plastic-steel PPS composite material includes a modified PPS matrix resin and an aramid fiber-based woven fabric composited within the modified PPS matrix resin. The aramid fiber-based woven fabric has a plain weave structure with a warp-weft knitted structure. The warp yarns are aramid fibers (Kuraray Vectran 50D aramid bulletproof yarn from Japan), with a spacing of 1 mm between adjacent warp yarns; the weft yarns are aramid fibers (Kuraray Vectran 50D aramid bulletproof yarn from Japan), with a spacing of 1 mm between adjacent weft yarns. In other words, the aramid fiber-based woven fabric has a 1 mm x 1 mm mesh.

[0075] The modified PPS matrix resin includes the following raw materials in parts by mass: 100 parts of PPS resin (Polyplastics of Japan, brand 0220A9, pure PPS resin, injection molding grade, melt viscosity of 260 Pa*s at 310°C), 5 parts of hyperbranched PPS resin, 50 parts of filler composition, 0.6 parts of dispersant K550 coupling agent, 0.6 parts of dispersant K570 coupling agent, 0.2 parts of dispersant titanate coupling agent HY-311, 1.6 parts of antioxidant 1024, and 0.4 parts of antioxidant 168.

[0076] Preparation of hyperbranched PPS resin: Add 10 g of 3,4-dichlorothiophenol, 3.4 g of anhydrous potassium carbonate, and 80 mL of N-methylpyrrolidone to a 250 mL three-necked flask. Heat to 150°C and maintain for 8.5 hours. Wash the product with hydrochloric acid, filter it, dissolve it in tetrahydrofuran, extract it with hexane, filter it, and dry it to obtain a light brown hyperbranched PPS powder.

[0077] The filler composition is composed of spherical filler, fibrous filler and flake filler in a mass ratio of 60:20:20.

[0078] The spherical filler consisted of spherical alumina, spherical silicon nitride, and spherical titanium nitride in a mass ratio of 80:10:10. The spherical alumina was composed of nano-spherical alumina with an average particle size of 300 nm (Jinzhong New Materials SINA-PROSPER, E300-1 Nano-Spherical Alumina), ultrafine spherical alumina with an average particle size of 3±1 μm (Wuhu Xinda New Materials Technology Co., Ltd., XD-LA03R), and spherical alumina with an average particle size of 30±3 μm (Wuhu Xinda New Materials Technology Co., Ltd., XD-LA30R), in a mass ratio of 15:60:25.

[0079] The average particle size of spherical silicon nitride is 3-5 μm, and Nangong Rongbang New Material Technology Co., Ltd. customizes the particle size to be 3-5 μm.

[0080] The average particle size of spherical titanium nitride is 2 μm, brand: Zhongke Yannuo, scientific research grade.

[0081] The fibrous filler is composed of a chopped aramid fiber composite, single-walled carbon nanotubes (CNT200 Zhongke Leiming, tube diameter 1-2 nm, length 5-30 μm), zinc oxide whiskers (tetrapod-shaped zinc oxide whiskers, XD-7.JX05, diameter 0.5-5 μm, length 10-50 μm, Wuhu Xinda New Material Technology Co., Ltd.), and potassium titanate whiskers (diameter 0.3-0.5 μm, length 5-40 μm, Wuhan Lanabai Pharmaceutical Chemical Co., Ltd.) in a mass ratio of 70:25:2:3.

[0082] The chopped aramid fiber composition is composed of DuPont Teijin para-aramid chopped PPTA with an equivalent diameter of 1 μm and a length of 0.5 mm, DuPont Teijin para-aramid chopped PPTA with an equivalent diameter of 1 μm and a length of 1 mm, DuPont Teijin para-aramid chopped PPTA with an equivalent diameter of 1 μm and a length of 3 mm, DuPont Teijin para-aramid chopped PPTA, and nano-aramid fiber in a mass ratio of 1:4:2:1.

[0083] Preparation method of nano-aramid fiber: Aramid nanofiber (ANF) is prepared by proton donor-assisted deprotonation method. S ) dispersion U51, specifically, 2 g of para-aramid PPTA fiber was weighed and placed in a mixed solution of 3 g KOH, 1.0 L DMSO and 40 mL deionized water, and stirred in a water bath at 60 ° C for 3 h to obtain a deep red ANF with a mass concentration of 2 g / L. S Aramid nanofibers ANF were obtained by nanofiltration S pink.

[0084] The flaky filler is composed of molybdenum sulfide nanosheets (brand: Yamei Nano, MoS2-200nm molybdenum disulfide nanosheets), boron nitride nanosheets (brand: Yamei Nano, hBN-500nm boron nitride nanosheets), and ultrafine mica sheets in a mass ratio of 5:5:90.

[0085] Preparation method of ultrafine mica flakes: 60-mesh high thermal conductivity and insulation phlogopite from Shijiazhuang Chenjin Mineral Products Co., Ltd. is used as raw material for high-speed ball milling, using zirconium oxide as grinding beads, and ball milling at a speed of 300 rpm for 60 minutes. The product is sieved with a 1250 mesh screen, and the sieved material is the ultrafine mica flakes.

[0086] A preparation process of a plastic-steel PPS composite material comprises the following steps:

[0087] Step 1: First, prepare a filler composition, and uniformly mix spherical fillers, fibrous fillers, and flaky fillers in a mass ratio of 60:20:20; then, perform surface modification on the prepared filler composition: place the filler composition in a surface modification liquid (the surface modification liquid is composed of a surface modifier and deionized water, and 100 parts of the surface modification liquid contains 6 parts of K570 coupling agent and 2 parts of dispersant titanate coupling agent HY-311) and perform ultrasonic dispersion treatment for 30 minutes at an ultrasonic dispersion frequency of 44 kHz and a power of 800 W, and then drain and dry to obtain a finished filler composition;

[0088] At the same time, the aramid fiber-based woven fabric is subjected to surface modification process to obtain the finished aramid fiber-based woven fabric:

[0089] S1.1. The aramid fiber-based woven fabric was ultrasonically cleaned in an ethanol-water solution (ethanol and deionized water in a 1 / 4 volume ratio) at a frequency of 44 kHz and a power of 800 W. After cleaning, the fabric was rinsed with clean water, dried, and set aside.

[0090] S1.2, performing low-temperature plasma treatment on the aramid fiber-based woven fabric, firstly treating the aramid fiber-based woven fabric with ozone at a temperature of 0-4°C for 100 seconds, and then treating the aramid fiber-based woven fabric with ammonia at a temperature of 0-4°C for 120 seconds, to obtain a semi-finished aramid fiber-based woven fabric;

[0091] S1.3, placing the aramid fiber-based woven fabric that has completed the low-temperature plasma treatment in a KH570 aqueous solution (KH570 concentration of 8 wt%), heating it to 50°C and performing ultrasonic dispersion treatment for 30 minutes at a frequency of 44 kHz and a power of 800 W. After the ultrasonic dispersion treatment, remove the aramid fiber-based woven fabric, drain it, and then dry it to obtain the finished aramid fiber-based woven fabric;

[0092] Step 2: The filler composition in step 1 is mixed and dispersed uniformly with correctly measured PPS resin, hyperbranched PPS resin, K550 coupling agent, K570 coupling agent, titanate coupling agent HY-311, antioxidant 1024, and antioxidant 168 at high speed, and then put into a twin-screw extruder. The four temperature sections of the barrel end temperature are set to 300° C., 315° C., 325° C., and 325° C. in sequence. The nozzle temperature is 325° C., the injection pressure is 95 MPa, the injection speed is 45 mm / s, and the screw rotation speed is 54 rpm. The molten extrudate ejected from the nozzle is subjected to wire drawing, nitrogen cooling, granulation, and drying (140° C. / 3 h) to obtain a PPS composite masterbatch.

[0093] Step 3: The prepared PPS composite masterbatch was put into a twin-screw extruder, and the four temperature sections of the barrel end temperature were set to 300°C, 315°C, 325°C, and 325°C, the nozzle temperature was 325°C, the mold temperature was 145°C, the injection pressure was 100 MPa, the injection speed was 60 mm / s, the holding pressure was 55 MPa, and the screw rotation speed was 65 rpm. A PPS sheet with a thickness of 0.35 mm was obtained by injection molding;

[0094] Step 4: stack to form a PPS sheet / finished aramid fiber-based woven fabric / PPS sheet structure, hot press for 500s at 288°C and 8MPa to obtain a PPS composite sheet, heat treat the obtained PPS composite sheet at 155°C for 45min, and naturally cool to room temperature to obtain a plastic-steel PPS composite sheet that meets the use requirements of battery shell materials.

[0095] The difference between Example 2 and Example 1 is that the modified PPS matrix resin includes the following raw materials in parts by mass: 100 parts of PPS resin, 10 parts of hyperbranched PPS resin, 52.4 parts of filler composition, 0.65 parts of dispersant K550 coupling agent, 0.65 parts of dispersant K570 coupling agent, 0.22 parts of dispersant titanate coupling agent HY-311, 1.6 parts of antioxidant 1024, and 0.4 parts of antioxidant 168.

[0096] The difference between Example 3 and Example 1 is that the modified PPS matrix resin includes the following raw materials in parts by mass: 100 parts of PPS resin, 15 parts of hyperbranched PPS resin, 54.7 parts of filler composition, 0.68 parts of dispersant K550 coupling agent, 0.68 parts of dispersant K570 coupling agent, 0.26 parts of dispersant titanate coupling agent HY-311, 1.6 parts of antioxidant 1024, and 0.4 parts of antioxidant 168.

[0097] The difference between Example 4 and Example 1 is that the modified PPS matrix resin includes the following raw materials in parts by mass: 100 parts of PPS resin, 20 parts of hyperbranched PPS resin, 57.1 parts of filler composition, 0.72 parts of dispersant K550 coupling agent, 0.72 parts of dispersant K570 coupling agent, 0.28 parts of dispersant titanate coupling agent HY-311, 1.6 parts of antioxidant 1024, and 0.4 parts of antioxidant 168.

[0098] The difference between Example 5 and Example 1 is that the modified PPS matrix resin includes the following raw materials in parts by mass: 100 parts of PPS resin, 15 parts of hyperbranched PPS resin, 60 parts of filler composition, 0.75 parts of dispersant K550 coupling agent, 0.75 parts of dispersant K570 coupling agent, 0.3 parts of dispersant titanate coupling agent HY-311, 1.6 parts of antioxidant 1024, and 0.4 parts of antioxidant 168.

[0099] The difference between Example 6 and Example 1 is that the modified PPS matrix resin includes the following raw materials in parts by mass: 100 parts of PPS resin, 15 parts of hyperbranched PPS resin, 70 parts of filler composition, 0.85 parts of dispersant K550 coupling agent, 0.85 parts of dispersant K570 coupling agent, 0.3 parts of dispersant titanate coupling agent HY-311, 1.6 parts of antioxidant 1024, and 0.4 parts of antioxidant 168.

[0100] The difference between Example 7 and Example 3 is that the filler composition is composed of spherical fillers, fibrous fillers, and flaky fillers in a mass ratio of 40:30:30.

[0101] The difference between Example 8 and Example 3 is that the filler composition is composed of spherical fillers, fibrous fillers, and flaky fillers in a mass ratio of 50:30:20.

[0102] The difference between Example 9 and Example 3 is that the filler composition is composed of spherical fillers, fibrous fillers, and flaky fillers in a mass ratio of 60:25:15.

[0103] The difference between Example 10 and Example 3 is that the filler composition is composed of spherical fillers, fibrous fillers, and flaky fillers in a mass ratio of 70:20:10.

[0104] The difference between Example 11 and Example 9 is that the filler composition is composed of spherical fillers, fibrous fillers, and flake fillers in a mass ratio of 80:10:10.

[0105] The difference between Example 12 and Example 9 is that the filler composition is composed of spherical fillers, fibrous fillers, and flaky fillers in a mass ratio of 90:5:5.

[0106] The difference between Example 13 and Example 9 is that the spherical alumina is composed of nano-spherical alumina with an average particle size of 300 nm, ultrafine spherical alumina with an average particle size of 3±1 μm, and spherical alumina with an average particle size of 30±3 μm in a mass ratio of 20:50:30.

[0107] The difference between Example 14 and Example 9 is that the spherical alumina is composed of nano-spherical alumina with an average particle size of 300 nm, ultrafine spherical alumina with an average particle size of 3±1 μm, and spherical alumina with an average particle size of 30±3 μm in a mass ratio of 25:35:45.

[0108] The difference between Example 15 and Example 9 is that the spherical alumina is composed of nano-spherical alumina with an average particle size of 300 nm, ultrafine spherical alumina with an average particle size of 3±1 μm, and spherical alumina with an average particle size of 30±3 μm in a mass ratio of 10:80:10.

[0109] The difference between Example 16 and Example 9 is that the spherical alumina is composed of nano-spherical alumina with an average particle size of 300 nm, ultrafine spherical alumina with an average particle size of 3±1 μm, and spherical alumina with an average particle size of 30±3 μm in a mass ratio of 30:40:30.

[0110] The difference between Example 17 and Example 9 is that the spherical alumina is ultrafine spherical alumina with an average particle size of 0.5-5 μm.

[0111] The difference between Example 18 and Example 9 is that the spherical filler is composed of spherical aluminum oxide, spherical silicon nitride, and spherical titanium nitride in a mass ratio of 85:10:5.

[0112] The difference between Example 19 and Example 9 is that the spherical filler is composed of spherical aluminum oxide, spherical silicon nitride, and spherical titanium nitride in a mass ratio of 90:5:5.

[0113] The difference between Example 20 and Example 9 is that the spherical filler is composed of spherical aluminum oxide, spherical silicon nitride, and spherical titanium nitride in a mass ratio of 95:3:2.

[0114] The difference between Example 21 and Example 9 is that the spherical filler is only spherical alumina. The spherical alumina is composed of nano-spherical alumina with an average particle size of 300nm, ultra-fine spherical alumina with an average particle size of 3±1μm, and spherical alumina with an average particle size of 30±3μm in a mass ratio of 15:60:25.

[0115] The difference between Example 22 and Example 18 is that the fibrous filler is composed of a chopped aramid fiber composition, single-walled carbon nanotubes, zinc oxide whiskers, and potassium titanate whiskers in a mass ratio of 65:30:2:3.

[0116] The difference between Example 23 and Example 18 is that the fibrous filler is composed of a chopped aramid fiber composition, single-walled carbon nanotubes, zinc oxide whiskers, and potassium titanate whiskers in a mass ratio of 60:35:2:3.

[0117] The difference between Example 24 and Example 18 is that the fibrous filler is composed of a chopped aramid fiber composition, single-walled carbon nanotubes, zinc oxide whiskers, and potassium titanate whiskers in a mass ratio of 55:45:2:3.

[0118] The difference between Example 25 and Example 18 is that the fibrous filler is composed of a chopped aramid fiber composition, single-walled carbon nanotubes, zinc oxide whiskers, and potassium titanate whiskers in a mass ratio of 45:50:2:3.

[0119] The difference between Example 26 and Example 18 is that the fibrous filler is composed of a chopped aramid fiber composition, single-walled carbon nanotubes, zinc oxide whiskers, and potassium titanate whiskers in a mass ratio of 35:60:2:3.

[0120] The difference between Example 27 and Example 18 is that the fibrous filler is composed of a chopped aramid fiber composition, single-walled carbon nanotubes, and potassium titanate whiskers in a mass ratio of 62:35:3.

[0121] The difference between Example 28 and Example 18 is that the fibrous filler is composed of a chopped aramid fiber composition, single-walled carbon nanotubes, and zinc oxide whiskers in a mass ratio of 63:35:2.

[0122] The difference between Example 29 and Example 18 is that the fibrous filler is composed of a chopped aramid fiber composition and single-walled carbon nanotubes in a mass ratio of 65:35.

[0123] The difference between Example 30 and Example 23 is that the flaky filler is composed of molybdenum sulfide nanosheets, boron nitride nanosheets, and ultrafine mica sheets in a mass ratio of 10:10:80.

[0124] The difference between Example 31 and Example 23 is that the flaky filler is composed of molybdenum sulfide nanosheets, boron nitride nanosheets, and ultrafine mica sheets in a mass ratio of 15:15:70.

[0125] The difference between Example 32 and Example 23 is that the flaky filler is composed of molybdenum sulfide nanosheets, boron nitride nanosheets, and ultrafine mica sheets in a mass ratio of 20:20:60.

[0126] The difference between Example 33 and Example 23 is that the flaky filler is composed of molybdenum sulfide nanosheets, boron nitride nanosheets, and ultrafine mica sheets in a mass ratio of 25:25:50.

[0127] The difference between Example 34 and Example 23 is that the flaky filler is composed of boron nitride nanosheets and ultrafine mica sheets in a mass ratio of 5:95.

[0128] The difference between Example 35 and Example 23 is that the flaky filler is composed of molybdenum sulfide nanosheets and ultrafine mica sheets in a mass ratio of 5:95.

[0129] The difference between Example 36 and Example 23 is that the flaky filler is only ultrafine mica flakes.

[0130] Example 37 differs from Example 23 in that the ultrafine mica flakes are replaced with mica flakes grafted with carbon nanotubes. Specifically, the flaky filler consists of molybdenum sulfide nanosheets, boron nitride nanosheets, and carbon nanotube-grafted mica flakes in a mass ratio of 5:5:90. The preparation method for the carbon nanotube-grafted mica flakes (manufactured by Zhejiang Rongtai Technology) is as follows:

[0131] Step 1: At room temperature, add 0.02 mol of 2-ethyl-4-methylimidazole 2E4MI and 0.01 mol of silver acetate AgAc to 400 mL of dichloromethane and stir magnetically at 240 r / min until the AgAc particles disappear completely to obtain a clear and transparent Ag(2E4MI)2Ac complex solution;

[0132] Step 2: Add 0.5 g of CNTs (TNGM2, Chengdu Institute of Organic Chemistry, Chinese Academy of Sciences) and 0.5 g of PVP to the Ag(2E4MI)2Ac complex solution, and use ultrasonic dispersion (power 1200 W, frequency 40 kHz) for 3 h. Add 50 g of ultrafine mica flakes and continue ultrasonic dispersion for 0.5 h to obtain a dispersion.

[0133] Step 3: The dispersion obtained in step 2 is subjected to vacuum distillation to remove dichloromethane from the dispersion, and then the solid is subjected to high-temperature sintering treatment. The high-temperature sintering temperature is controlled at 210° C. and the high-temperature sintering time is 4 hours to obtain a solid;

[0134] Step 4: The solid obtained in step 3 is placed in a three-roll mill for three grinding cycles with a roller spacing of 30 μm. The solid is then dispersed in 400 mL of ethanol and poured into a basket grinder for grinding at a speed of 2000 r / min for 0.5 h. The solid is then filtered and dried to obtain an ultrafine mica sheet-CNTs hybrid material.

[0135] Example 38 differs from Example 21 in that the ultrafine mica flakes are replaced with surface-graphene-grafted mica flakes. Specifically, the flaky filler consists of molybdenum sulfide nanosheets, boron nitride nanosheets, and surface-graphene-grafted mica flakes in a mass ratio of 5:5:90. The preparation method for surface-graphene-grafted mica flakes (manufactured by Zhejiang Rongtai Technology) is as follows:

[0136] Step 1: At room temperature, add 0.02 mol of 2-ethyl-4-methylimidazole 2E4MI and 0.01 mol of silver acetate AgAc to 400 mL of dichloromethane and stir magnetically at 240 r / min until the AgAc particles disappear completely to obtain a clear and transparent Ag(2E4MI)2Ac complex solution;

[0137] Step 2: Add 0.5 g of graphene nanosheets (industrial-grade nanographene sheets TNIGNP, Chengdu Institute of Organic Chemistry, Chinese Academy of Sciences) and 0.5 g of PVP to the Ag(2E4MI)2Ac complex solution, and use ultrasonic dispersion (power 1200 W, frequency 40 kHz) for 3 h. Add 50 g of ultrafine mica flakes and continue ultrasonic dispersion for 0.5 h to obtain a dispersion.

[0138] Step 3: The dispersion obtained in step 2 is subjected to vacuum distillation to remove dichloromethane from the dispersion, and then the solid is subjected to high-temperature sintering treatment. The high-temperature sintering temperature is controlled at 210° C. and the high-temperature sintering time is 4 hours to obtain a solid;

[0139] Step 4: The solid obtained in step 3 is placed in a three-roll mill for three grinding cycles with a roller spacing of 30 μm. The solid is then dispersed in 400 mL of ethanol and poured into a basket grinder for grinding at a speed of 2000 r / min for 0.5 h. The solid is then filtered and dried to obtain an ultrafine mica sheet-CNTs hybrid material.

[0140] Example 39 differs from Example 21 in that the ultrafine mica flakes are replaced with surface-graphene-grafted mica flakes and surface-carbon nanotube-grafted mica flakes. Specifically, the flaky filler comprises molybdenum sulfide nanosheets, boron nitride nanosheets, the surface-graphene-grafted mica flakes of Example 33, and the surface-carbon nanotube-grafted mica flakes of Example 32 in a mass ratio of 5:5:45:45.

[0141] Example 40 differs from Example 1 in that the aramid fiber-based woven fabric has a plain weave structure with a warp-weft knitting structure. The warp yarns are aramid fibers (Kuraray Vectran 50D aramid bulletproof yarn from Japan) and 1K Toray carbon fiber filaments, with the spacing between adjacent aramid fibers being 1 mm. The weft yarns are aramid fibers (Kuraray Vectran 50D aramid bulletproof yarn from Japan) and 1K Toray carbon fiber filaments, with the spacing between adjacent aramid fibers being 1 mm. In other words, the aramid fiber-based woven fabric has a 1 mm x 1 mm mesh.

[0142] Example 41 differs from Example 1 in that the aramid fiber-based woven fabric has a plain weave structure, with the warp threads composed of aramid fiber (Kuraray Vectran 50D aramid ballistic yarn from Japan) and 1K Toray carbon fiber filaments, with the spacing between adjacent aramid fibers being 0.5 mm. The weft threads are composed of aramid fiber (Kuraray Vectran 50D aramid ballistic yarn from Japan) and 1K Toray carbon fiber filaments, with the spacing between adjacent aramid fibers being 0.5 mm. In other words, the aramid fiber-based woven fabric has a mesh size of 0.5 mm by 0.5 mm.

[0143] Example 42 differs from Example 1 in that the aramid fiber-based woven fabric has a plain weave structure with a warp-weft knitting pattern. The warp yarns are aramid fibers (Kuraray Vectran 50D aramid bulletproof yarn from Japan) and 1K Toray carbon fiber filaments, with the spacing between adjacent aramid fibers being 2 mm. The weft yarns are aramid fibers (Kuraray Vectran 50D aramid bulletproof yarn from Japan) and 1K Toray carbon fiber filaments, with the spacing between adjacent aramid fibers being 2 mm. In other words, the aramid fiber-based woven fabric has a 2 mm x 2 mm mesh.

[0144] Example 43 differs from Example 1 in that the aramid fiber-based woven fabric has a plain weave structure with a warp-weft knitting pattern. The warp yarns are aramid fibers (Kuraray Vectran 50D aramid bulletproof yarn from Japan) and 1K Toray carbon fiber filaments, with the spacing between adjacent aramid fibers being 3 mm. The weft yarns are aramid fibers (Kuraray Vectran 50D aramid bulletproof yarn from Japan) and 1K Toray carbon fiber filaments, with the spacing between adjacent aramid fibers being 3 mm. In other words, the aramid fiber-based woven fabric has a 3 mm x 3 mm mesh.

[0145] The difference between Example 44 and Example 1 is that in step 1, the aramid fiber-based woven fabric is subjected to a surface modification process to obtain a finished aramid fiber-based woven fabric. The specific surface modification process is as follows:

[0146] S1.1. The aramid fiber-based woven fabric was ultrasonically cleaned in an ethanol-water solution (ethanol and deionized water in a 1 / 4 volume ratio) at a frequency of 44 kHz and a power of 800 W. After cleaning, the fabric was rinsed with clean water, dried, and set aside.

[0147] S1.2, first subjecting the aramid fiber-based woven fabric to low-temperature plasma treatment, first subjecting the aramid fiber-based woven fabric to low-temperature plasma treatment at 0-4°C for 100 seconds, and then subjecting the aramid fiber-based woven fabric to low-temperature plasma treatment at 0-4°C for 120 seconds, to obtain a semi-finished aramid fiber-based woven fabric; then subjecting the aramid fiber-based woven fabric in S1.1 to a sol-gel method treatment, so that nano-alumina particles are in situ generated on the surface of the warp and weft threads in the aramid fiber-based woven fabric, thereby achieving surface alumina doping modification of the aramid fiber-based woven fabric surface;

[0148] S1.3. Place the surface alumina-doped modified aramid fiber-based woven fabric in a KH570 aqueous solution (KH570 concentration is 8wt%), heat it to 50°C and perform ultrasonic dispersion treatment for 30 minutes. The ultrasonic dispersion frequency is 44kHz and the power is 800W. After completing the ultrasonic dispersion treatment, take out the aramid fiber-based woven fabric, drain it and dry it to obtain the finished aramid fiber-based woven fabric.

[0149] The difference between Example 45 and Example 44 is that the filler composition is composed of spherical fillers, fibrous fillers, and flaky fillers in a mass ratio of 60:25:15. The spherical fillers are composed of spherical aluminum oxide, spherical silicon nitride, and spherical titanium nitride in a mass ratio of 85:10:5. The fibrous fillers are composed of a chopped aramid fiber composition, single-walled carbon nanotubes, zinc oxide whiskers, and potassium titanate whiskers in a mass ratio of 60:35:2:3. The flaky fillers are composed of molybdenum sulfide nanosheets, boron nitride nanosheets, the surface graphene-grafted modified mica sheets of Example 33, and the surface carbon nanotube-grafted modified mica sheets of Example 32 in a mass ratio of 5:5:45:45.

[0150] The difference between Comparative Example 1 and Example 1 is that the modified PPS matrix resin includes the following raw materials in parts by mass: 100 parts of PPS resin, 5 parts of hyperbranched PPS resin, 40 parts of filler composition, 0.45 parts of dispersant K550 coupling agent, 0.45 parts of dispersant K570 coupling agent, 0.12 parts of dispersant titanate coupling agent HY-311, 1.6 parts of antioxidant 1024, and 0.4 parts of antioxidant 168.

[0151] The difference between Comparative Example 2 and Example 1 is that the modified PPS matrix resin includes the following raw materials in parts by mass: 100 parts of PPS resin, 5 parts of hyperbranched PPS resin, 80 parts of filler composition, 0.9 parts of dispersant K550 coupling agent, 0.9 parts of dispersant K570 coupling agent, 0.24 parts of dispersant titanate coupling agent HY-311, 1.6 parts of antioxidant 1024, and 0.4 parts of antioxidant 168.

[0152] The difference between Comparative Example 3 and Example 1 is that the modified PPS matrix resin includes the following raw materials in parts by mass: 100 parts of PPS resin, 0 parts of hyperbranched PPS resin, 47.6 parts of filler composition, 0.5 parts of dispersant K550 coupling agent, 0.5 parts of dispersant K570 coupling agent, 0.15 parts of dispersant titanate coupling agent HY-311, 1.6 parts of antioxidant 1024, and 0.4 parts of antioxidant 168.

[0153] The difference between Comparative Example 4 and Example 1 is that the modified PPS matrix resin includes the following raw materials in parts by mass: 100 parts of PPS resin, 2 parts of hyperbranched PPS resin, 48.6 parts of filler composition, 0.55 parts of dispersant K550 coupling agent, 0.55 parts of dispersant K570 coupling agent, 0.17 parts of dispersant titanate coupling agent HY-311, 1.6 parts of antioxidant 1024, and 0.4 parts of antioxidant 168.

[0154] The difference between Comparative Example 5 and Example 1 is that the modified PPS matrix resin includes the following raw materials in parts by mass: 100 parts of PPS resin, 22 parts of hyperbranched PPS resin, 58.2 parts of filler composition, 0.8 parts of dispersant K550 coupling agent, 0.8 parts of dispersant K570 coupling agent, 0.3 parts of dispersant titanate coupling agent HY-311, 1.6 parts of antioxidant 1024, and 0.4 parts of antioxidant 168.

[0155] The difference between Comparative Example 6 and Example 1 is that the modified PPS matrix resin includes the following raw materials in parts by mass: 100 parts of PPS resin, 5 parts of hyperbranched PPS resin, 50 parts of filler composition, 1.2 parts of dispersant K550 coupling agent, 0 parts of dispersant K570 coupling agent, 0.2 parts of dispersant titanate coupling agent HY-311, 1.6 parts of antioxidant 1024, and 0.4 parts of antioxidant 168.

[0156] The difference between Comparative Example 7 and Example 1 is that the modified PPS matrix resin includes the following raw materials in parts by mass: 100 parts of PPS resin, 5 parts of hyperbranched PPS resin, 50 parts of filler composition, 0 parts of dispersant K550 coupling agent, 1.2 parts of dispersant K570 coupling agent, 0.2 parts of dispersant titanate coupling agent HY-311, 1.6 parts of antioxidant 1024, and 0.4 parts of antioxidant 168.

[0157] The difference between Comparative Example 8 and Example 1 is that the modified PPS matrix resin includes the following raw materials in parts by mass: 100 parts of PPS resin, 5 parts of hyperbranched PPS resin, 50 parts of filler composition, 1.4 parts of dispersant K550 coupling agent, 0 parts of dispersant K570 coupling agent, 0 parts of dispersant titanate coupling agent HY-311, 1.6 parts of antioxidant 1024, and 0.4 parts of antioxidant 168.

[0158] The difference between Comparative Example 9 and Example 1 is that the modified PPS matrix resin includes the following raw materials in parts by mass: 100 parts of PPS resin, 5 parts of hyperbranched PPS resin, 50 parts of filler composition, 0 parts of dispersant K550 coupling agent, 1.4 parts of dispersant K570 coupling agent, 0 parts of dispersant titanate coupling agent HY-311, 1.6 parts of antioxidant 1024, and 0.4 parts of antioxidant 168.

[0159] The difference between Comparative Example 10 and Example 1 is that the modified PPS matrix resin includes the following raw materials in parts by mass: 100 parts of PPS resin, 5 parts of hyperbranched PPS resin, 50 parts of filler composition, 1.2 parts of dispersant K550 coupling agent, 0 parts of dispersant K570 coupling agent, 0.2 parts of dispersant titanate coupling agent HY-311, and 2 parts of antioxidant 1024.

[0160] The difference between Comparative Example 11 and Example 1 is that 50 parts of the filler composition are replaced by 50 parts of spherical fillers.

[0161] The difference between Comparative Example 12 and Example 1 is that 50 parts of the filler composition are replaced by 50 parts of fibrous filler.

[0162] The difference between Comparative Example 13 and Example 1 is that 50 parts of the filler composition are replaced by 50 parts of the flaky filler.

[0163] The difference between Comparative Example 14 and Example 1 is that the filler composition consists of spherical fillers and fibrous fillers in a mass ratio of 6:4.

[0164] The difference between Comparative Example 15 and Example 1 is that the filler composition consists of spherical fillers and flaky fillers in a mass ratio of 6:4.

[0165] The difference between Comparative Example 16 and Example 1 is that the filler composition consists of fibrous filler and flaky filler in a mass ratio of 1:1.

[0166] The difference between Comparative Example 17 and Example 1 is that no aramid fiber-based woven fabric is provided inside the modified PPS matrix resin.

[0167] The difference between Comparative Example 18 and Example 1 is that the aramid fiber-based woven fabric is not subjected to the surface modification process in step one.

[0168] The difference between Comparative Example 19 and Example 1 is that in step 1, the aramid fiber-based woven fabric is subjected to a surface modification process to obtain a finished aramid fiber-based woven fabric. The specific surface modification process is as follows:

[0169] S1.1. The aramid fiber-based woven fabric was ultrasonically cleaned in an ethanol-water solution (ethanol and deionized water in a 1 / 4 volume ratio) at a frequency of 44 kHz and a power of 800 W. After cleaning, the fabric was rinsed with clean water, dried, and set aside.

[0170] S1.2, performing low-temperature plasma treatment on the aramid fiber-based woven fabric, firstly treating the aramid fiber-based woven fabric with ozone at a low-temperature plasma temperature of 0-4°C for 100 seconds to obtain a semi-finished aramid fiber-based woven fabric;

[0171] S1.3. Place the semi-finished aramid fiber-based woven fabric in S1.2 in a KH570 aqueous solution (KH570 concentration is 8 wt%), heat it to 50°C and perform ultrasonic dispersion treatment for 30 minutes. The ultrasonic dispersion frequency is 44 kHz and the power is 800 W. After the ultrasonic dispersion treatment is completed, take out the aramid fiber-based woven fabric, drain it and then dry it to obtain the finished aramid fiber-based woven fabric.

[0172] The control group was the existing 40wt% GF modified polyphenylene sulfide material.

[0173] Performance Testing: 1. Tensile properties are measured in accordance with ISO 527-2. 2. Charpy impact strength (unnotched) is measured in accordance with ISO 179. 3. Flexural strength is measured in accordance with ISO 178. 4. Dielectric strength (3mm) is measured in accordance with IEC 60243. 5. Thermal conductivity is measured in accordance with GB / T 10295-2008 Thermal insulation materials - Determination of steady-state thermal resistance and related properties - Heat flow meter method.

[0174] Table 1: Test parameters of plastic-steel PPS composite panels in Examples 1-6 and Comparative Examples 1-10

[0175]

[0176] It can be seen from Examples 1-6, Comparative Examples 1-2 and Table 1 that the appropriate amount of the filler composition to be added is 50-70 parts.

[0177] Combining Examples 1-6, Comparative Examples 3-5 and Table 1, it can be seen that the addition amount of the hyperbranched PPS resin is preferably 5-20 parts. Too low an addition amount will reduce the overall impact toughness; while too high an addition amount will affect the overall mechanical strength.

[0178] Combining Example 1, Comparative Examples 6-9 and Table 1, it can be seen that the dispersant compounded with KH-550 silane coupling agent, KH-570 silane coupling agent and titanate coupling agent HY-311 can effectively disperse the filler composition and improve the overall physical and chemical properties.

[0179] From Example 1, Comparative Example 10 and Table 1, it can be seen that the combination of antioxidant 1024 and antioxidant 168 can improve the thermal oxidative degradation resistance of PPS resin, that is, improve the anti-aging performance and ensure the overall physical and chemical properties.

[0180] Combining Examples 1-6, Comparative Examples 1-2 and Table 1, it can be seen that the modified PPS matrix resin formula provided in Example 3 is better, the addition amount of the filler composition is 54.7 parts, and the addition amount of the hyperbranched PPS resin is 15 parts.

[0181] Table 2: Test parameters of plastic-steel PPS composite panels in Examples 3, 7-12 and Comparative Examples 11-16

[0182]

[0183] Combining Examples 3, 7-12 and Comparative Examples 11-16 with Table 2, it can be seen that the addition of fibrous filler in the filler composition significantly improves the tensile properties, but excessive addition of fibrous filler will lead to a large decrease in insulation strength. Therefore, the proportion of fibrous filler in the filler composition is preferably 20-30wt%, and the preferred amount of fibrous filler added is 25wt%.

[0184] In combination with Examples 3, 7-12 and Comparative Examples 11-16 and Table 2, it can be seen that the filler composition composed of spherical fillers, fibrous fillers, and flaky fillers in a mass ratio of (50-80):(10-30):(10-20) can ensure that the physical and chemical properties of the prepared plastic-steel PPS composite material meet the requirements of battery casing materials. Preferably, the spherical fillers, fibrous fillers, and flaky fillers in the filler composition are in a mass ratio of 60:25:15 to ensure the mechanical strength, impact toughness, and heat dissipation of the prepared plastic-steel PPS composite material.

[0185] Table 3: Test parameters of plastic-steel PPS composite panels in Example 9 and Examples 13-21

[0186]

[0187] Combining Examples 9 and 13-17 with Table 3, it can be seen that the particle size distribution of the spherical alumina in the filler composition has a significant impact on the mechanical strength, impact toughness, and heat dissipation of the prepared plastic-steel PPS composite material. When the spherical alumina system is composed of nano-spherical alumina with an average particle size of 300 nm, ultrafine spherical alumina with an average particle size of 3±1 μm, and spherical alumina with an average particle size of 30±3 μm in a mass ratio of (15-25):(35-60):(25-40), the prepared plastic-steel PPS composite material exhibits relatively good overall performance in terms of mechanical strength, impact toughness, and heat dissipation, while also reducing production costs.

[0188] In combination with Example 9 and Examples 18-21 and Table 3, it can be seen that the spherical silicon nitride and spherical titanium nitride contained in the spherical filler have a positive effect on the heat aging resistance processing performance of the plastic-steel PPS composite material. When the spherical aluminum oxide, spherical silicon nitride, and spherical titanium nitride are composed of spherical fillers in a mass ratio of (80-90): (5-10): (5-10), the comprehensive performance of the prepared plastic-steel PPS composite material is relatively good. Preferably, the mass ratio of spherical aluminum oxide, spherical silicon nitride, and spherical titanium nitride is 85:10:5.

[0189] Table 4: Test parameters of plastic-steel PPS composite panels in Example 18 and Examples 22-29

[0190]

[0191] Combining Examples 18 and 22-26 with Table 4, it can be seen that the optimal single-walled carbon nanotube content in the fibrous filler is 25-50 wt% of the total mass of the fibrous filler. Excessive addition can significantly reduce insulation resistance to electrical breakdown. When the single-walled carbon nanotube content accounts for 35 wt% of the total mass of the fibrous filler, the overall performance of the plastic-steel PPS composite material is superior.

[0192] Combining Example 18 and Examples 27-29 with Table 4, it can be seen that the addition of appropriate amounts of zinc oxide whiskers and potassium titanate whiskers can improve the tensile properties, impact toughness, resistance to thermal oxidative degradation, and hot extrusion processing performance of the plastic-steel PPS composite material.

[0193] Table 5: Test parameters of plastic-steel PPS composite panels in Example 23 and Examples 30-39

[0194]

[0195] In conjunction with Example 23 and Examples 30-39 and in conjunction with Table 5, it can be seen that the addition of molybdenum sulfide nanosheets and boron nitride nanosheets has a positive effect on the tensile properties and impact toughness of the plastic-steel PPS composite material. When the molybdenum sulfide nanosheets, boron nitride nanosheets, and ultrafine mica sheets are composed in a mass ratio of (5-20): (5-20): (60-90), the comprehensive properties of the prepared plastic-steel PPS composite material are relatively excellent. Preferably, the molybdenum sulfide nanosheets, boron nitride nanosheets, and ultrafine mica sheets are in a mass ratio of 10:10:80.

[0196] From Example 30 and Examples 37-39 and Table 5, it can be seen that the addition of surface carbon nanotube grafted modified mica sheets and / or surface graphene grafted modified mica sheets can improve the thermal conductivity and tensile properties of the plastic-steel PPS composite material while still maintaining relatively good insulation safety performance.

[0197] Table 6: Test parameters of plastic-steel PPS composite panels in Example 1, Examples 40-45, and Comparative Examples 17-19

[0198]

[0199] Combining Example 1 with Comparative Examples 17-19 and Table 6, it can be seen that the aramid fiber-based woven fabric requires specific surface treatment to achieve better compatibility with the modified PPS matrix resin, thereby improving the overall tensile properties and impact toughness.

[0200] Combining Example 1 and Example 40 and Table 6, it can be seen that the addition of carbon fiber to the aramid fiber-based woven fabric can further improve the tensile properties and impact toughness of the plastic-steel PPS composite material and also have certain insulation and electrical breakdown resistance, meeting the use requirements of battery casing materials.

[0201] Combining Example 1 with Examples 40-43 and Table 6, it can be seen that the mesh size formed by the warp and weft threads in the aramid fiber-based woven fabric has a certain impact on the mechanical properties and impact strength of the plastic-steel PPS composite material. The mesh size formed by the warp and weft threads is preferably controlled to be 0.5 mm * 0.5 mm to 2 mm * 2 mm, and preferably the mesh size formed by the warp and weft threads is controlled to be 1 mm * 1 mm.

[0202] Combining Example 1 with Example 44 and Table 6, it can be seen that the fiber surface of the aramid fiber-based woven fabric in Example 44 is treated by a sol-gel method to in-situ generate nano-alumina particles to improve the overall insulation and electrical breakdown resistance, and also has good heat dissipation, tensile strength and impact toughness.

[0203] In summary, the composite design of the compound filler composition and hyperbranched PPS resin combined with the built-in aramid fiber-based woven fabric adopted in this application effectively improves the overall mechanical strength, thermal stability, chemical corrosion resistance, electrical properties, wear resistance and flame retardant properties of the plastic-steel PPS composite material, and at the same time has excellent impact toughness, meeting the requirements of battery shell materials.

[0204] This specific embodiment is merely an explanation of the present application and is not a limitation of the present application. After reading this specification, those skilled in the art may make non-creative modifications to the present embodiment as needed, but as long as they are within the scope of the claims of the present application, they are protected by the patent law.

Claims

1. A plastic-steel PPS composite material, characterized by: The invention comprises a modified PPS matrix resin and at least one aramid fiber-based woven fabric compounded inside the modified PPS matrix resin, wherein the aramid fiber-based woven fabric is a plain weave warp-weft knitted structure, wherein the warp yarns of the aramid fiber-based woven fabric at least comprise aramid fibers, and the weft yarns at least comprise aramid fibers; The modified PPS matrix resin is made of the following raw materials in parts by mass: 100 parts of PPS resin, 5-20 parts of hyperbranched PPS resin, 50-70 parts of filler composition, 0.5-2 parts of dispersant, and 1-3 parts of anti-aging agent; The dispersant is at least one of stearate, siloxane coupling agent and titanate coupling agent; The anti-aging agent is at least one of antioxidant 1024, antioxidant 4426, antioxidant 300, antioxidant 168, and antioxidant 626; The filler composition comprises a combination of spherical fillers, fibrous fillers and flake fillers. The spherical filler includes at least one of spherical alumina, spherical aluminum nitride, spherical silicon dioxide, spherical silicon nitride, spherical titanium nitride, and spherical silicon carbide; The fibrous filler comprises at least one of nanocarbon fibers, chopped aramid fiber compositions, carbon nanotubes, cellulose nanofibers, and inorganic whiskers; The inorganic whiskers include at least one of zinc oxide whiskers, aluminum oxide whiskers, zirconium oxide, aluminum nitride whiskers, boron nitride whiskers, silicon dioxide whiskers, silicon nitride whiskers, silicon carbide whiskers, calcium carbonate whiskers, and potassium titanate whiskers; The flaky filler comprises at least one of graphene nanosheets, boron nitride nanosheets, MXene phase ceramic nanosheets, ultrafine mica sheets, and molybdenum sulfide nanosheets; The mass ratio of the spherical filler, the fibrous filler, and the flake filler is (50-80):(10-30):(10-20); the aramid fiber-based woven fabric is treated by a surface modification process; The surface modification process of the aramid fiber-based woven fabric is as follows: Step 1: The aramid fiber-based woven fabric is ultrasonically cleaned in an ethanol-water solution, then rinsed with clean water, dried, and set aside; Step 2: treating the aramid fiber-based woven fabric with low-temperature plasma, first with ozone at 0-4°C for 60-300s, and then with ammonia at 0-4°C for 60-300s, to obtain a semi-finished aramid fiber-based woven fabric; Step three, placing the aramid fiber-based woven fabric that has completed the low-temperature plasma treatment in a methacryloxysilane aqueous solution, heating it to 45-50°C and performing ultrasonic dispersion treatment for 20-40 minutes, wherein the methacryloxysilane concentration in the methacryloxysilane aqueous solution is 4-8wt%. After completing the ultrasonic dispersion treatment, the aramid fiber-based woven fabric is taken out, drained, and then dried to obtain the finished aramid fiber-based woven fabric.

2. The plastic-steel PPS composite material according to claim 1, characterized in that: The spherical filler is composed of spherical alumina, spherical silicon nitride and spherical titanium nitride in a mass ratio of (80-90): (5-10): (5-10); the spherical alumina is composed of nano-spherical alumina with an average particle size of 100-400nm, spherical silicon nitride with an average particle size of 0.5-5 μm Ultrafine spherical alumina, average particle size 25-50 μm The spherical aluminum oxide is composed of a mass ratio of (15-25): (35-60): (25-40); the average particle size of the spherical silicon nitride is 0.8-5 μm; The average particle size of spherical titanium nitride is 0.02-5 μm .

3. The plastic-steel PPS composite material according to claim 2, characterized in that: The fibrous filler is composed of a chopped aramid fiber composition, single-walled carbon nanotubes, zinc oxide whiskers, and potassium titanate whiskers; the mass ratio of the chopped aramid fiber composition, single-walled carbon nanotubes, zinc oxide whiskers, and potassium titanate whiskers is (40-73):(25-50):(1-5):(1-5).

4. The plastic-steel PPS composite material according to claim 3, characterized in that: The flaky filler consists of molybdenum sulfide nanosheets, boron nitride nanosheets and ultrafine mica sheets.

5. The plastic-steel PPS composite material according to claim 4, characterized in that: The ultrafine mica sheet is a surface carbon nanotube grafted modified mica sheet and / or a surface graphene grafted modified mica sheet; the surface carbon nanotube grafted modified mica sheet includes an ultrafine mica sheet carrier with a particle size of ≤1250 mesh and carbon nanotubes fixed to the ultrafine mica sheet carrier with a particle size of ≤1250 mesh by nanosilver sintering; the surface graphene grafted modified mica sheet includes an ultrafine mica sheet carrier with a particle size of ≤1250 mesh and graphene nanosheets fixed to the ultrafine mica sheet carrier with a particle size of ≤1250 mesh by nanosilver sintering.

6. The plastic-steel PPS composite material according to claim 4, characterized in that: The mass ratio of the spherical filler, the fibrous filler and the flaky filler is (55-60):(20-25):(15-20); the dispersant is composed of KH-550 silane coupling agent, KH-570 silane coupling agent and titanate coupling agent HY-311 in a mass ratio of (0.5-2):(0.5-2):(0.1-0.4).

7. The plastic-steel PPS composite material according to claim 1, characterized in that: The spacing between adjacent warps of the aramid fiber-based woven fabric is 0.5-2 mm; the spacing between adjacent wefts is 0.5-2 mm; the warps in the aramid fiber-based woven fabric include aramid fiber filaments and carbon fiber filaments arranged at intervals from each other; the wefts in the aramid fiber-based woven fabric include aramid fiber filaments and carbon fiber filaments arranged at intervals from each other.

8. A process for preparing a plastic-steel PPS composite material according to any one of claims 1 to 7, characterized in that: The following steps are involved: Step 1: First, prepare a filler composition, and then perform surface modification on the prepared filler composition: place the filler composition in a surface modification solution and perform ultrasonic dispersion treatment for 20-40 minutes, then drain and dry to obtain a finished filler composition; the surface modification solution is composed of a surface modifier and deionized water, and the surface modifier is a siloxane coupling agent and / or a titanate coupling agent; At the same time, the aramid fiber-based woven fabric is subjected to a surface modification process to obtain a finished aramid fiber-based woven fabric; Step 2: The filler composition in step 1 is mixed and dispersed uniformly with the correctly measured PPS resin, hyperbranched PPS resin, dispersant, and anti-aging agent at high speed, and then fed into a twin-screw extruder. The mixture is melt-extruded at a barrel end temperature of 285-325° C., subjected to wire drawing, nitrogen cooling, granulation, and drying to obtain a PPS composite masterbatch. Step 3: using PPS composite masterbatch for injection molding to form a PPS sheet with a thickness of 0.25-0.40 mm; Step 4: stack to form a PPS sheet / finished aramid fiber-based woven fabric / PPS sheet structure, hot press at 280-300°C and 5-15MPa for 5-15min to obtain a PPS composite sheet, heat treat the obtained PPS composite sheet at 140-160°C for 30-60min, and naturally cool to room temperature to obtain a plastic-steel PPS composite sheet that meets the use requirements of battery casing materials.

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