Carbon fiber modified polyketone composite material and preparation method thereof

Abstract

The invention discloses a carbon fiber modified polyketone composite material and a preparation method thereof, and the preparation method comprises the following steps: mixing polyketone, a compatilizer and an auxiliary agent to obtain a premix; adding the premix into a main feeding hopper of a double-screw extruder, adding the modified short carbon fibers into a hopper of a forced side feeding machine, and carrying out melt extrusion to obtain a carbon fiber modified polyketone composite material; the processing temperature of melt extrusion is as follows: a conveying section is 140-160 DEG C, a melt plasticizing section is 220-235 DEG C, a side material section is 220-230 DEG C, a mixing dispersion section is 220-230 DEG C, an exhaust section is 220-230 DEG C, a metering homogenization section is 220-235 DEG C, and the temperature of a machine head is 180-200 DEG C. According to the application, through a synergistic enhancement strategy of interface bridging and construction of a nanometer material-carbon fiber-POK resin three-dimensional mechanical interlocking network, and through optimization of POK resin type selection, carbon fiber type selection, a carbon fiber coating, a carbon fiber length-diameter ratio and the like, a processing window of polyketone is widened, and the heat resistance of the polyketone is improved.

Description

Technical Field

[0001] This application relates to the field of polymer materials, and in particular to a carbon fiber modified polyketone composite material and its preparation method. Background Technology

[0002] Polyketone (POK) is a semi-crystalline, high-performance polymer formed by alternating copolymerization of carbon monoxide and olefins (such as ethylene and propylene). Its regular carbonyl structure along its main chain endows the material with excellent mechanical strength, outstanding chemical resistance, superior wear resistance, high barrier properties, and good weather resistance. Based on these comprehensive properties, POK shows great application potential in automotive fuel system components, electronic and electrical connectors, mechanical parts such as gears and bearings, and packaging materials.

[0003] However, POK materials still face two key technical bottlenecks in their expansion into wider high-end applications: First, their melt processing window is relatively narrow, and their melt strength is highly sensitive to temperature. Improper temperature control during molding can easily lead to melt fracture, product defects, or degradation due to overheating, posing a serious challenge to the precise control of processing equipment and the stability of the process. Second, although POK itself possesses a certain degree of heat resistance, its heat distortion temperature and other indicators still need further improvement for applications requiring long-term operation under high temperature and high load conditions (such as automotive engine peripheral components and high-speed precision gears).

[0004] To overcome the above limitations, fiber reinforcement is commonly used in this field for modification. Carbon fiber (CF) is considered an ideal reinforcing material due to its extremely high specific strength, specific modulus, excellent heat resistance and low density. Introducing it into the POK matrix can theoretically significantly improve the mechanical properties and heat distortion temperature of the composite material. However, practice shows that simple physical blending has limited effect, mainly due to the following problems: (1) The surface of carbon fiber is chemically inert and smooth, resulting in weak interfacial adhesion between it and the POK matrix, which leads to low stress transfer efficiency, greatly reducing the reinforcing effect, and is prone to interfacial debonding, which becomes a crack source, affecting the toughness and fatigue life of the material; (2) The introduction of carbon fiber, especially when added in high content, will further aggravate the rheological complexity of the POK melt, which may make the already narrow processing window even more difficult to control, and the dispersion process is extremely demanding; (3) Excessive shearing fracture of carbon fiber during processing will lead to a decrease in its aspect ratio, weakening its reinforcing efficiency.

[0005] Currently, conventional methods for improving the compatibility of carbon fiber and polymer interfaces include surface sizing of the carbon fiber or the use of coupling agents. While general-purpose sizing agents (such as polyamide-based and epoxy resin-based agents) can provide some improvement, their specific interactions with the POK matrix are limited, and it is difficult to precisely control the structure and properties of the interfacial phase at the nanoscale. Furthermore, existing technologies do not offer clear and effective solutions for systematically optimizing composite process parameters (such as screw assembly, feeding method, and processing temperature) from carbon fiber selection and surface treatment to matching with specific matrices (such as POK) to significantly improve mechanical and heat resistance properties while broadening the material's processability window. Most studies remain at the level of simple examination of single variables (such as fiber content), lacking a deep understanding of the synergistic design and control of the entire "resin-fiber interface-processing technology" system.

[0006] Therefore, developing an innovative method that can fundamentally strengthen interfacial bonding, achieve multi-scale synergistic enhancement, and simultaneously endow POK composite materials with a wider processing window and higher heat resistance has become the key to promoting the application of POK in high-end engineering fields, and is also a technical problem that urgently needs to be solved in this field. Summary of the Invention

[0007] In view of this, this application provides a method for preparing carbon fiber modified polyketone composite materials. The preparation method is simple, low in cost, highly controllable, and easy to industrialize.

[0008] This application provides a method for preparing carbon fiber modified polyketone composite materials, including:

[0009] Polyketone, compatibilizer and additives are mixed to obtain a premix;

[0010] The premixed material is added to the main feed hopper of a twin-screw extruder, and the modified carbon fiber short fibers are added to the hopper of a forced side feeder. The mixture is then melt-extruded to obtain a carbon fiber modified polyketone composite material.

[0011] The processing temperature of the melt extrusion is 140~160℃ in the conveying section, 220~235℃ in the melt plasticizing section, 220~230℃ in the side material section, 220~230℃ in the mixing and dispersing section, 220~230℃ in the venting section, 220~230℃ in the metering and homogenizing section, and 180~200℃ in the die head temperature.

[0012] The mass ratio of polyketone, modified carbon fiber short fiber, compatibilizer and additives is (50~100):(5~50):(1~5):(0.5~5).

[0013] In some specific implementations, the polyketide is a ternary copolymer of carbon monoxide, ethylene, and propylene, and has a melt index of 10~1000 g / 10 min at 240°C.

[0014] In some specific implementations, the modified carbon fiber short fiber is obtained by impregnating and modifying carbon fiber short fibers with a modified dispersion solution;

[0015] The modified dispersion comprises a silane coupling agent and surface-modified nanomaterials;

[0016] The mass ratio of the silane coupling agent to the surface-modified nanomaterial is (0.8~1.2):1;

[0017] The silane coupling agent includes one or more of KH550, KH560, KH570 or titanate coupling agents;

[0018] The modified carbon fiber short fiber has a length of 0.1 mm to 15 mm, a diameter of 3 μm to 30 μm, and an appearance shape of either cylindrical or sheet-like, preferably sheet-like.

[0019] The modified carbon fiber short fiber surface also includes a sizing agent layer, wherein the sizing agent includes one or more of polyamide, polyurethane, polyester, epoxy, phenolic, polyolefin, polyimide resin, nitrile rubber or styrene-butadiene rubber;

[0020] The surface-modified nanomaterials include one or more of the following: aminated carbon nanotubes, carboxylated graphene, boehmite nanosheets modified with silane coupling agents, hydroxylated Mxene, or aramid nanofibers.

[0021] The surface-modified nanomaterials have one-dimensional or two-dimensional nanostructures with an aspect ratio of 50 to 10000 and an average diameter of 1 nm to 1000 nm.

[0022] In some specific implementations, the compatibilizer includes one or more of the following: maleic anhydride-grafted ethylene-octene copolymer, maleic anhydride-grafted polyethylene copolymer, maleic anhydride-grafted polypropylene copolymer, maleic anhydride-grafted ethylene-butene copolymer, maleic anhydride-grafted carbon monoxide-ethylene polyketide copolymer, maleic anhydride-grafted carbon monoxide-ethylene-propylene polyketide copolymer, glycidyl methacrylate-grafted polyketide copolymer, methacrylic acid-grafted polyketide copolymer, acrylic acid-grafted polyketide copolymer, acrylamide-grafted polyketide copolymer, or methyl methacrylate-grafted polyketide copolymer.

[0023] In some specific implementations, the additives include one or more of antioxidants, external lubricants, internal lubricants, anti-fiber leakage agents, or ultraviolet absorbers;

[0024] The mass ratio of the antioxidant, external lubricant, internal lubricant, anti-fiber leakage agent, and ultraviolet absorber is (0.1~0.5):(0.1~0.5):(0.1~0.5):(2~8):(0.2~0.8).

[0025] The antioxidants include primary antioxidants and secondary antioxidants. The primary antioxidants include hindered phenolic antioxidants such as pentaerythritol tetrakis(3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate) 1010, octadecyl-3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate 1076, and 2,6-di-tert-butyl-p-cresol BHT264. 1098 or one or more of 1,3,5-trimethyl-2,4,6-tris(3,5-di-tert-butyl-4-hydroxybenzyl)benzene 1313, wherein the co-antioxidant comprises one or more of the following phosphite antioxidants: tris(2,4-di-tert-butylphenyl) phosphite 168, bis(octadecyl pentaerythritol diphosphite 618, bis(2,4-di-tert-butylphenyl) pentaerythritol diphosphite 626, diphenyl pentaerythritol diphosphite DPDP, or dilauryl thiodipropionate DLTDP. Multiple types are included; the external lubricant comprises one or more of polyethylene wax, polypropylene wax, Fischer-Tropsch wax, stearic acid, or stearic acid metal soap; the internal lubricant comprises one or more of pentaerythritol stearate, butyl stearate, glyceryl monostearate, oleamide, erucamide, or ethylene bis-stearamide; the anti-fiber leakage agent comprises one or more of modified polyethylene wax, acrylate copolymers, or polysiloxanes; and the ultraviolet absorber comprises UV-326, UV-327, and UV-329. One or more of (triazine-5) or hindered amine light stabilizer 622.

[0026] In some specific implementations, the melt extrusion is carried out in a twin-screw extruder;

[0027] The screw components in the twin-screw extruder are, in sequence, a conveying section, a melting and plasticizing section, a side-positioning material section, a mixing and dispersing section, a venting section, and a metering and homogenizing section.

[0028] In some specific implementations, the twin-screw extruder is a parallel co-rotating twin-screw extruder with a screw length-to-diameter ratio of 44:1 and a screw diameter D of 35 mm;

[0029] The conveying section of the screw element in the twin-screw extruder is a forward conveying element, accounting for 10% to 20% of the length, with a lead of 16 to 96 mm and a pitch of 16 to 48 mm.

[0030] In some specific implementations, the melting and plasticizing section of the screw element in the twin-screw extruder adopts a combination of a gradually decreasing lead forward conveying screw element and a kneading block, accounting for 20% to 35% of the length. The lead of the forward conveying screw element is 16 to 48 mm, the pitch of the forward conveying screw element is 11 to 48 mm, the shear angle of the kneading block is 45° to 90°, the number is 4 to 10, and the pitch is 11 to 48 mm.

[0031] The side section of the screw element in the twin-screw extruder adopts a forward conveying screw element, with a length ratio of 15% to 25% and a lead of 16 to 96 mm. The pitch of the kneading block is 16 to 48 mm.

[0032] The mixing and dispersing section of the twin-screw extruder screw element adopts a combination of a tapered lead forward conveying screw element, a kneading block, and a ZME strong dispersing element, accounting for 15% to 20% of the length. The forward conveying screw element has a lead of 16 to 48 mm and a pitch of 11 to 48 mm. The kneading block has a shear angle of 45° to 90° and consists of 4 to 8 blocks with a pitch of 11 to 48 mm. The ZME strong dispersing element has a lead of 4 to 22 mm and a pitch of 8 to 32 mm.

[0033] The exhaust section of the twin-screw extruder uses a large-lead forward conveying screw element, accounting for 5% to 10% of the length, with a lead of 16 to 48 mm and a pitch of 11 to 48 mm. It is equipped with a vacuum exhaust port with a vacuum degree of -0.06 to -0.09 MPa.

[0034] In some specific implementations, the metering and homogenization section of the twin-screw extruder screw element adopts a forward conveying screw element with a gradually decreasing lead, accounting for 5% to 15% of the length, with a lead of 16 to 48 mm and a pitch of 11 to 48 mm;

[0035] The modified carbon fiber short fibers are fed into the extruder via a forced side feeder, and the feed screw adopts a parallel twin-screw structure.

[0036] This application also provides a carbon fiber modified polyketone composite material, which is prepared according to the preparation method described above.

[0037] This application employs a synergistic enhancement strategy involving interface bridging and the construction of a three-dimensional mechanically interlocked network of "nanomaterials-carbon fiber-POK resin," along with formulation adjustments and process optimization, to significantly improve the mechanical strength of polyketone, broaden its processing window, and enhance its heat resistance. Detailed Implementation

[0038] It should be understood that the expression “one or more of…” individually includes each of the objects described after the expression, as well as various different combinations of two or more of the described objects, unless otherwise understood from the context and usage. The expression “and / or” combined with three or more described objects should be understood to have the same meaning, unless otherwise understood from the context.

[0039] The terms “including,” “having,” or “containing,” including the use of their grammatical synonyms, should generally be understood as open-ended and non-restrictive, for example, not excluding other unstated elements or steps, unless otherwise specifically stated or understood from the context.

[0040] It should be understood that the order of steps or the sequence of actions is not important as long as this application remains operational. Furthermore, two or more steps or actions can be performed simultaneously.

[0041] The use of any and all instances or exemplary language such as “e.g.” or “include” in this document is intended merely to better illustrate the application and does not constitute a limitation on the scope of the application. No language in this specification should be construed as indicating that any unclaimed element is essential to the practice of this application.

[0042] Furthermore, the numerical ranges and parameters used to define this application are approximate values, and the relevant values ​​in the specific embodiments have been presented as precisely as possible. However, any numerical value inevitably contains standard deviations due to individual test methods. Therefore, unless otherwise explicitly stated, it should be understood that all ranges, quantities, values, and percentages used in this disclosure are modified with the word "approximately." Here, "approximately" generally means that the actual value is within plus or minus 10%, 5%, 1%, or 0.5% of a specific value or range.

[0043] Given the high melt viscosity and narrow processing window of polyketone (POK), and its susceptibility to cross-linking and thermal degradation under high temperature and strong mechanical shear, its heat resistance is limited. In existing technologies using carbon fiber reinforced POK, excessive carbon fiber breakage and short retention lengths often occur due to conventional screw element combinations, carbon fiber addition methods, and low interfacial bonding strength, reducing the reinforcement effect and failing to effectively improve thermal stability. This application provides a carbon fiber modified POK composite material, which, through the addition of POK, modified short carbon fibers, compatibilizers, and additives, and by adjusting the formulation and optimizing the process, gives POK excellent mechanical strength and heat resistance, and effectively broadens the processing window.

[0044] Based on the characteristics of POK material, the selection of modified carbon fiber short fibers and surface coating materials, and the optimization of their composite process with POK matrix, especially the screw combination and feeding process in the twin-screw extrusion process, are crucial for preparing carbon fiber modified polyketone composite materials with wide processing window, high heat resistance and excellent comprehensive performance.

[0045] This application provides a method for preparing carbon fiber modified polyketone composite materials, including:

[0046] Polyketone, compatibilizer and additives are mixed to obtain a premix;

[0047] The premixed material is added to the main feed hopper of a twin-screw extruder, and the modified carbon fiber short fibers are added to the hopper of a forced side feeder. The mixture is then melt-extruded to obtain a carbon fiber modified polyketone composite material.

[0048] The processing temperature of the melt extrusion is 140~160℃ in the conveying section, 220~235℃ in the melt plasticizing section, 220~230℃ in the side material section, 220~230℃ in the mixing and dispersing section, 220~230℃ in the venting section, 220~230℃ in the metering and homogenizing section, and 180~200℃ in the die head temperature.

[0049] The mass ratio of polyketone, modified carbon fiber short fiber, compatibilizer and additives is (50~100):(5~50):(1~5):(0.5~5), preferably (57~92):(5~40):(1~5):1.4.

[0050] This application first mixes polyketone, compatibilizer, and additives to obtain a premix. In some specific implementations, the polyketone is a ternary copolymer of carbon monoxide, ethylene, and propylene, an aliphatic polyketone, with a melt index of 10~1000 g / 10 min at 240℃ and 2.16 kg, which can be 10 g / 10 min, 50 g / 10 min, 100 g / 10 min, 150 g / 10 min, 200 g / 10 min, 300 g / 10 min, 500 g / 10 min, 600 g / 10 min, 800 g / 10 min, or 1000 g / 10 min. In some specific implementations, the compatibilizer includes, but is not limited to, one or more of the following: maleic anhydride-grafted ethylene-octene copolymer, maleic anhydride-grafted polyethylene copolymer, maleic anhydride-grafted polypropylene copolymer, maleic anhydride-grafted ethylene-butene copolymer, maleic anhydride-grafted carbon monoxide-ethylene polyketide copolymer, maleic anhydride-grafted carbon monoxide-ethylene-propylene polyketide copolymer, glycidyl methacrylate-grafted polyketide copolymer, methacrylic acid-grafted polyketide copolymer, acrylic acid-grafted polyketide copolymer, acrylamide-grafted polyketide copolymer, or methyl methacrylate-grafted polyketide copolymer. This application does not have special requirements for the selection of the compatibilizer, but maleic anhydride-grafted carbon monoxide-ethylene-propylene polyketide copolymer is preferred. In some specific implementations, the mixing is carried out in a high-speed mixer. During the mixing process in the high-speed mixer, some additives may be added as needed. These additives can be one or more commonly used auxiliaries in the art, including antioxidants, external lubricants, internal lubricants, anti-fiber leakage agents, or ultraviolet absorbers, without particular limitation.

[0051] The modified carbon fiber short fibers have amino groups on their surface that can form chemical bonds with the compatibilizer maleic anhydride-grafted carbon monoxide-ethylene-propylene polyketone copolymer. As a result, the interfacial bonding strength of the carbon fiber modified polyketone composite material is enhanced, and the mechanical strength and heat resistance are higher.

[0052] In some specific implementations, the additives include one or more of antioxidants, external lubricants, internal lubricants, anti-fiber leakage agents, or ultraviolet absorbers;

[0053] The mass ratio of the antioxidant, external lubricant, internal lubricant, anti-fiber leakage agent, and ultraviolet absorber is (0.1~0.5):(0.1~0.5):(0.1~0.5):(2~8):(0.2~0.8), preferably 0.2:0.3:0.3:3:0.5;

[0054] The antioxidants include primary antioxidants and secondary antioxidants. The primary antioxidants include hindered phenolic antioxidants such as pentaerythritol tetrakis(3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate) 1010, octadecyl-3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate 1076, and 2,6-di-tert-butyl-p-cresol BHT264. 1098, 1,3,5-trimethyl-2,4,6-tris(3,5-di-tert-butyl-4-hydroxybenzyl)benzene 1313, wherein the co-antioxidant includes phosphite antioxidants tris(2,4-di-tert-butylphenyl) phosphite 168, bis(octadecyl pentaerythritol diphosphite) 618, bis(2,4-di-tert-butylphenyl) pentaerythritol diphosphite 626, diphenyl pentaerythritol diphosphite DPDP, and dilauryl thiodipropionate DLTDP; The external lubricant includes polyethylene wax, polypropylene wax, Fischer-Tropsch wax, stearic acid, and its metal soaps; the internal lubricant includes pentaerythritol stearate, butyl stearate, glyceryl monostearate, oleamide, erucamide, and ethylene bis-stearamide; the anti-fiber leakage agent includes modified polyethylene wax, acrylate copolymers, and polysiloxanes; and the ultraviolet absorber includes UV-326, UV-327, UV-329, triazine-5, and hindered amine light stabilizer 622. In some specific implementations, the mass ratio of the primary antioxidant to the secondary antioxidant is 1:(0.8~1.2), preferably 1:1.

[0055] This application then adds the premixed material to the main feed hopper of a twin-screw extruder, and the modified carbon fiber short fibers are added to the hopper of a forced side feeder for melt extrusion to obtain a carbon fiber modified polyketone composite material. In some specific implementations, the modified carbon fiber short fibers are obtained by impregnating and modifying carbon fiber short fibers with a modified dispersion liquid;

[0056] The carbon fiber short fibers include, but are not limited to, one or more of PAN-based carbon fiber, pitch-based carbon fiber, and viscose fiber-based carbon fiber. This application does not have any special requirements for the selection of carbon fiber short fibers.

[0057] The modified carbon fiber short fiber has a length of 0.1 mm to 15 mm, which can be 0.1 mm, 0.5 mm, 1 mm, 2 mm, 5 mm, 8 mm, 10 mm, 12 mm, or 15 mm, preferably 3 mm to 10 mm, and a diameter of 3 μm to 30 μm, which can be 3 μm, 5 μm, 10 μm, 15 μm, 20 μm, 25 μm, or 30 μm, preferably 5 μm to 12 μm, and an appearance shape of either cylindrical or sheet-like, preferably sheet-like.

[0058] The modified carbon fiber short fiber surface also includes a sizing agent layer, wherein the sizing agent includes one or more of polyamide, polyurethane, polyester, epoxy, phenolic, polyolefin, polyimide resin, nitrile rubber or styrene-butadiene rubber, preferably PA;

[0059] The silane coupling agent includes, but is not limited to, one or more of KH550, KH560, KH570, or titanate coupling agents. This application does not have specific requirements for the selection of the silane coupling agent, but surface impregnation modification with silane coupling agent KH550 is preferred. The surface-modified nanomaterials include one or more of aminated carbon nanotubes, carboxylated graphene, boehmite nanosheets modified with silane coupling agents, hydroxylated Mxene, or aramid nanofiber fillers, preferably aramid nanofibers. The surface-modified nanomaterials have one-dimensional or two-dimensional nanostructures with an aspect ratio of 50-10000 and an average diameter of 1 nm-1000 nm, preferably an aspect ratio of 1000 and a diameter of 10 nm. In some specific implementations, the premix is ​​added to the main feed hopper of a twin-screw extruder, and the modified carbon fiber short fibers are added to the hopper of a forced side feeder for melt blending and extrusion to obtain a carbon fiber modified polyketide composite material.

[0060] In some specific implementations, the melt extrusion is carried out in a twin-screw extruder;

[0061] The screw components in the twin-screw extruder are, in sequence, a conveying section, a melting and plasticizing section, a side-positioning material section, a mixing and dispersing section, a venting section, and a metering and homogenizing section.

[0062] In some specific implementations, the twin-screw extruder is a parallel co-rotating twin-screw extruder with a screw length-to-diameter ratio of 44:1 and a screw diameter D of 35 mm;

[0063] The conveying section of the screw element in the twin-screw extruder is a forward conveying element, accounting for 10% to 20% of the length, with a lead of 16 to 96 mm and a pitch of 16 to 48 mm. The screw element combination can be 32 / 32A, 48 / 48, 48 / 48, 32 / 32, 32 / 32, 32 / 32, 32 / 32, or 32 / 32.

[0064] In some specific implementations, the melting and plasticizing section of the twin-screw extruder uses a combination of a tapered lead forward conveying screw element and a kneading block, accounting for 20% to 35% of the length. The forward conveying screw element has a lead of 16 to 48 mm and a pitch of 11 to 48 mm. The kneading block has a shear angle of 45° to 90°, and there are 4 to 10 blocks with a pitch of 11 to 48 mm. The screw element combination can be 90° / 5 / 32, 90° / 5 / 32, 32 / 32, 32 / 32, 22 / 22, 22 / 22, 22 / 22, 22 / 22, 22 / 22, 22 / 22, 22 / 22, 22 / 22, 22 / 22, 32 / 32, 32 / 32, 60° / 5 / 32, 60° / 5 / 32, or 22 / 11.

[0065] The side section of the screw element in the twin-screw extruder adopts a forward conveying screw element, with a length ratio of 15% to 25%, a lead of 16 to 96 mm, and a pitch of 16 to 48 mm. The screw element combination can be 48 / 48, 48 / 48, 48 / 48, 32 / 32, 48 / 48, 48 / 48, or 48 / 48, and is used for receiving modified carbon fiber short fibers fed from the receiving side.

[0066] The mixing and dispersing section of the twin-screw extruder screw elements adopts a combination of a tapered lead forward conveying screw element, a kneading block, and a ZME strong dispersing element, accounting for 15% to 20% of the length. The forward conveying screw element has a lead of 16 to 48 mm and a pitch of 11 to 48 mm. The kneading block has a shear angle of 45° to 90°, and there are 4 to 8 of them with a pitch of 11 to 48 mm. The ZME strong dispersing element has a lead of 4 to 22 mm and a pitch of 8 to 32 mm. The screw element combination can be 32 / 32, 32 / 32, 45° / 4 / 22, 45° / 4 / 22, 60° / 5 / 32, 22 / 22, 22 / 22, 22 / 22, ZME 8 / 16, ZME 8 / 16, ZME 8 / 16, ZME 8 / 16;

[0067] The exhaust section of the twin-screw extruder uses a large-lead forward-feeding screw element, accounting for 5% to 10% of the length, with a lead of 16 to 48 mm and a pitch of 11 to 48 mm. The screw element combination can be 48 / 48, 48 / 48, or 32 / 32, and a vacuum exhaust port is provided with a vacuum degree of -0.06 to -0.09 MPa. The lower the vacuum degree, the easier it is for water vapor and other small gas molecules generated during extrusion to be discharged, and the smaller the impact on the polyketone resin.

[0068] In some specific implementations, the metering and homogenization section of the twin-screw extruder screw element adopts a forward conveying screw element with a gradually decreasing lead, accounting for 5% to 15% of the length, with a lead of 16 to 48 mm and a pitch of 11 to 48 mm. The screw element combination can be 32 / 32, 32 / 32, 32 / 32, 32 / 32, or 22 / 22.

[0069] The modified carbon fiber short fibers are fed into the extruder via a forced side feeder, and the feed screw adopts a parallel twin-screw structure.

[0070] This application significantly broadens the processing window of polyketone and improves its heat resistance and mechanical strength by optimizing material selection and extrusion process.

[0071] This application also provides a carbon fiber modified polyketone composite material, which is prepared according to the preparation method described above.

[0072] The carbon fiber modified polyketone composite material comprises, by weight, 50 to 100 parts polyketone, 5 to 50 parts modified carbon fiber short fibers, 1 to 5 parts compatibilizer, and 0.5 to 5 parts additives.

[0073] The present application is further illustrated below with reference to embodiments. The scope of protection of the present application is not limited to the following embodiments.

[0074] Except for the self-made raw materials, all other experimental materials used in the following embodiments of this application are commercially available products. Specifically, the polyketone granules were purchased from Hyosung, South Korea; the carbon fiber staples were purchased from Jilin Chemical Fiber; the antioxidants included a primary antioxidant and a secondary antioxidant, with the primary antioxidant being hindered phenolic antioxidant 1010 and the secondary antioxidant being phosphite antioxidant 168, with a weight ratio of antioxidant 1010 to phosphite antioxidant 168 of 1:1; the internal lubricant was a high-temperature lubricant, pentaerythritol stearate, purchased from Jiangxi Zhilian New Materials Co., Ltd., model PETS-4; the external lubricant was polyethylene wax, and the anti-floating fiber leakage agent was modified polyethylene wax, both purchased from Qingdao Sainuo Chemical Co., Ltd.; the ultraviolet absorber was UV-326, purchased from Jinwei Nanomaterials Co., Ltd.; the aramid nanofibers were purchased from Shandong Jufang New Materials Co., Ltd.; the silane coupling agent was purchased from Hubei Xinlantian New Materials Co., Ltd.; and nylon 6 was purchased from Zhejiang Xinhecheng Special Materials Co., Ltd.

[0075] Preparation Example 1

[0076] This preparation example provides a modified carbon fiber staple fiber (sheet-like KH550 / aramid nanofiber surface-modified carbon fiber staple fiber with PAN-based PA sizing agent) for use in subsequent examples. The preparation method is as follows:

[0077] (1) Preparation of aramid nanofiber dispersion: Aramid nanofiber gel (solid content 4.0% wt) was dispersed in deionized water with an aspect ratio of 1000 and a diameter of 10 nm to form a stable homogeneous dispersion with a solid content of 0.3% wt.

[0078] (2) Silane coupling agent KH550 hydrolysate: KH550 is mixed with ethanol and water in a certain proportion (KH550:ethanol:water = 1:9:1 volume ratio), and stirred at room temperature for 1 hour to obtain a clear KH550 hydrolysate prepolymer solution.

[0079] (3) Modified dispersion: The aramid nanofiber dispersion prepared above is slowly mixed with KH550 hydrolysate under stirring conditions, wherein the mass ratio of aramid nanofiber to KH550 is 1:1, and the pH value of the mixed dispersion is adjusted to 4~9 with ammonia or acetic acid.

[0080] (4) Impregnation treatment: First, the PAN-based sheet carbon fiber short fibers are pretreated by high temperature calcination (500℃) to remove the outer oil stains and sizing agent on the surface. Then, they are impregnated in the modified dispersion prepared in step (3) at a temperature of 80℃. The uniformity of the dispersion is maintained by mechanical stirring and the fiber is kept in full contact with the liquid. The impregnation time is 1 hour. After drying, the PAN-based sheet KH550 / aramid nanofiber surface modified carbon fiber short fibers are obtained.

[0081] (5) Sizing treatment: First, Nylon 6 is added to a 40% formic acid aqueous solution to prepare a sizing agent with suitable viscosity, uniformity and transparency. Then, the PAN-based sheet KH550 / aramid nanofiber surface-modified carbon fiber short fiber obtained in step (4) is immersed in the prepared sizing agent for 0.5 hours to ensure that the fiber bundle is fully wetted and the liquid volume is precisely controlled. Finally, after drying and curing at low temperature (80℃) and high temperature (150℃) and cooling, the sheet KH550 / aramid nanofiber surface-modified carbon fiber short fiber with PAN-based PA sizing agent is obtained.

[0082] Example 1

[0083] This embodiment provides a carbon fiber modified polyketone composite material, comprising, by weight, 92 parts of polyketone with a melt index of 200 g / 10min, 5 parts of sheet-like KH550 / aramid nanofiber surface-modified carbon fiber short fibers (6 mm in length and 6 μm in diameter) with PAN-based PA sizing agent provided in Preparation Example 1, 0.2 parts of antioxidant, 0.3 parts of external lubricant, 0.3 parts of internal lubricant, 0.1 parts of ultraviolet absorber, 3 parts of maleic anhydride-grafted carbon monoxide-ethylene-propylene polyketone copolymer compatibilizer, and 0.5 parts of anti-floating fiber leakage agent. The preparation method of the carbon fiber modified polyketone composite material includes:

[0084] (1) The raw and auxiliary materials such as polyketone, antioxidant, external lubricant, internal lubricant, ultraviolet absorber, maleic anhydride grafted carbon monoxide-ethylene-propylene polyketone copolymer compatibilizer, and anti-floating fiber leakage agent are weighed according to the proportion and added to the high-speed mixer. After mixing, a premix is ​​obtained.

[0085] (2) The premixed material was added to the main feed hopper of the twin-screw extruder, while the PAN-based PA sizing agent flakes of KH550 / aramid nanofiber surface-modified carbon fiber short fibers were added to the forced side feeder hopper. The ratio of main feeder to side feeder was 95:5. The mixture was melt-blended and extruded to obtain a carbon fiber modified polyketide composite material. The twin-screw extruder had a screw length-to-diameter ratio of 44:1 and a screw diameter D of 35 mm. mm; the screw element assembly consists of a conveying section, a melting and plasticizing section, a side-positioning material section, a mixing and dispersing section, a venting section, and a metering and homogenizing section. The conveying section configurations are 32 / 32A, 48 / 48, 48 / 48, 32 / 32, 32 / 32, 32 / 32, 32 / 32, 32 / 32, with a processing temperature of 160℃. The melting and plasticizing section configurations are 90° / 5 / 32, 90° / 5 / 32, 32 / 32, 32 / 32, 22 / 22, 22 / 22, 22 / 22, 22 / 22, 22 / 22, 22 / 22, 22 / 22, 22 / 22, 22 / 22, 22 / 22, 22 / 22, 32 / 32, 32 / 32, 90° / 5 / 32, 90° / 5 / 32, 22 / 11, processing temperature is 235℃, side material section combination is 48 / 48, 48 / 48, 48 / 48, 32 / 32, 48 / 48, 48 / 48, 48 / 48, processing temperature is 230℃, mixing and dispersing section combination is 32 / 32, 32 / 32, 45° / 4 / 22, 45° / 4 / 22, 60° / 5 / 32, 22 / 22, 22 / 22, 22 / 22, ZME 8 / 16, ZME 8 / 16, ZME 8 / 16, ZME 8 / 16, processing temperature is 220℃, exhaust section combination is 48 / 48, 48 / 48, 32 / 32, processing temperature is 230℃, metering homogenization section combination is 32 / 32, 32 / 32, 32 / 32, 32 / 32, 22 / 22, processing temperature is 235℃, and die head temperature is 200℃.

[0086] Example 2

[0087] This embodiment provides a carbon fiber modified polyketone composite material, which differs from Example 1 only in that: the melt index 200 g / 10min polyketone in step (1) is 87 parts, the PAN-based PA sizing agent with sheet-like KH550 / aramid nanofiber surface modified carbon fiber short fiber in step (2) is 10 parts, the main feed and side feed ratio is 90:10, and the other parameters and steps are consistent with Example 1.

[0088] Example 3

[0089] This embodiment provides a carbon fiber modified polyketone composite material, which differs from Example 1 only in that: the polyketone with a melt index of 200 g / 10min is 77 parts, the PAN-based PA sizing agent in step (2) is 20 parts of the sheet-like KH550 / aramid nanofiber surface-modified carbon fiber short fiber, and the ratio of main feed to side feed is 80:20. The remaining parameters and steps are consistent with Example 1.

[0090] Example 4

[0091] This embodiment provides a carbon fiber modified polyketone composite material, which differs from Example 1 only in that: the polyketone with a melt index of 200 g / 10min is 67 parts, the PAN-based PA sizing agent in step (2) is 30 parts of the sheet-like KH550 / aramid nanofiber surface-modified carbon fiber short fiber, and the ratio of main feed to side feed is 70:30. The remaining parameters and steps are consistent with those of Example 1.

[0092] Example 5

[0093] This embodiment provides a carbon fiber modified polyketone composite material, which differs from Example 1 only in that: the polyketone with a melt index of 200 g / 10min is 57 parts, the PAN-based PA sizing agent in step (2) is 40 parts of the sheet-like KH550 / aramid nanofiber surface-modified carbon fiber short fiber, and the ratio of main feed to side feed is 60:40. The remaining parameters and steps are consistent with Example 1.

[0094] Example 6

[0095] This embodiment provides a carbon fiber modified polyketone composite material, which differs from Example 3 only in that: the compatibilizer is 0 parts, the polyketone with a melt index of 200 g / 10min is 90 parts, and the other parameters and steps are the same as in Example 3.

[0096] Example 7

[0097] This embodiment provides a carbon fiber modified polyketone composite material, which differs from Example 3 only in that: the compatibilizer is 1 part, the polyketone with a melt index of 200 g / 10min is 89 parts, and the other parameters and steps are the same as in Example 3.

[0098] Example 8

[0099] This embodiment provides a carbon fiber modified polyketone composite material, which differs from Example 3 only in that: the compatibilizer is 5 parts, the polyketone with a melt index of 200 g / 10min is 85 parts, and the other parameters and steps are the same as in Example 3.

[0100] Example 9

[0101] This embodiment provides a carbon fiber modified polyketone composite material, which differs from Example 3 only in that the processing temperature of the mixing and dispersion section is 230 ℃, while the other parameters and steps are the same as in Example 3.

[0102] Example 10

[0103] This embodiment provides a carbon fiber modified polyketone composite material, which differs from Example 3 only in that the processing temperature of the mixing and dispersion section is 225 ℃, while the other parameters and steps are the same as in Example 3.

[0104] Example 11

[0105] This embodiment provides a carbon fiber modified polyketone composite material, which differs from Example 3 only in that the melt index of polyketone in step (1) is 10 g / 10 min, while the other parameters and steps are consistent with Example 3.

[0106] Example 12

[0107] This embodiment provides a carbon fiber modified polyketone composite material, which differs from Example 3 only in that the PAN-based PA sizing agent in step (2) is replaced with the PAN-based PA sizing agent with the PAN-based PA sizing agent with the PAN-based PA sizing agent. The remaining parameters and steps are the same as in Example 3.

[0108] Example 13

[0109] This embodiment provides a carbon fiber modified polyketone composite material, which differs from Example 3 only in that the PAN-based PA sizing agent in step (2) is replaced with the PAN-based PA sizing agent in step (3) with the PAN-based PA sizing agent in step (4) with the PAN-based PA sizing agent in step (5) with the PAN-based PA sizing agent. The remaining parameters and steps are the same as in Example 3.

[0110] Example 14

[0111] This embodiment provides a carbon fiber modified polyketone composite material, which differs from Example 3 only in that the sheet-like KH550 / aramid nanofiber surface-modified carbon fiber short fiber of PAN-based PA sizing agent in step (2) is changed to the sheet-like KH550 / aramid nanofiber surface-modified carbon fiber short fiber of PAN-based polyurethane sizing agent. The remaining parameters and steps are consistent with Example 3.

[0112] Example 15

[0113] This embodiment provides a carbon fiber modified polyketone composite material, which differs from Example 3 only in that the PAN-based PA sizing agent in step (2) is replaced with PAN-based polyester sizing agent in step (3) with PAN-based polyester sizing agent. The remaining parameters and steps are consistent with Example 3.

[0114] Example 16

[0115] This embodiment provides a carbon fiber modified polyketone composite material, which differs from Example 3 only in that the PAN-based PA sizing agent in step (2) is replaced with PAN-based epoxy sizing agent in step (3). The remaining parameters and steps are the same as in Example 3.

[0116] Example 17

[0117] This embodiment provides a carbon fiber modified polyketone composite material, which differs from Example 3 only in that the PAN-based PA sizing agent in step (2) is replaced with PAN-based polyolefin sizing agent with PAN-based polyolefin sizing agent and PAN-based polyolefin nanofiber surface modified carbon fiber short fibers. The remaining parameters and steps are consistent with Example 3.

[0118] Example 18

[0119] This embodiment provides a carbon fiber modified polyketone composite material, which differs from Example 3 only in that the PAN-based PA sizing agent in step (2) is replaced with PAN-based polyimide sizing agent in step (3). The remaining parameters and steps are the same as in Example 3.

[0120] Example 19

[0121] This embodiment provides a carbon fiber modified polyketone composite material, which differs from Example 3 only in that: the length of the sheet-like KH550 / aramid nanofiber surface-modified carbon fiber short fiber in step (2) of the PAN-based PA sizing agent is 1 mm, and the other parameters and steps are consistent with Example 3.

[0122] Example 20

[0123] This embodiment provides a carbon fiber modified polyketone composite material, which differs from Example 3 only in that: the PAN-based PA sizing agent in step (2) has a sheet-like KH550 / aramid nanofiber surface-modified carbon fiber short fiber of 15 mm, and the other parameters and steps are consistent with Example 3.

[0124] Example 21

[0125] This embodiment provides a carbon fiber modified polyketone composite material, which differs from Example 3 only in that: the diameter of the carbon fiber short fiber modified on the surface of the PAN-based PA sizing agent in step (2) is 3 μm, and the other parameters and steps are consistent with Example 3.

[0126] Example 22

[0127] This embodiment provides a carbon fiber modified polyketone composite material, which differs from Example 3 only in that the diameter of the carbon fiber short fiber modified on the surface of the PAN-based PA sizing agent in step (2) is 30 μm. The other parameters and steps are consistent with those in Example 3.

[0128] Example 23

[0129] This embodiment provides a carbon fiber modified polyketone composite material, which differs from Example 3 only in that the sheet-like KH550 / aramid nanofiber surface-modified carbon fiber short fiber of PAN-based PA sizing agent in step (2) is changed to the cylindrical KH550 / aramid nanofiber surface-modified carbon fiber short fiber of PAN-based PA sizing agent. The remaining parameters and steps are consistent with Example 3.

[0130] Example 24

[0131] This embodiment provides a carbon fiber modified polyketone composite material, which differs from Example 3 only in that the sheet-like KH550 / aramid nanofiber surface-modified carbon fiber short fiber of PAN-based PA sizing agent in step (2) is changed to the sheet-like KH560 / aramid nanofiber surface-modified carbon fiber short fiber of PAN-based PA sizing agent. The remaining parameters and steps are consistent with Example 3.

[0132] Example 25

[0133] This embodiment provides a carbon fiber modified polyketone composite material, which differs from Example 3 only in that the PAN-based PA sizing agent in step (2) is replaced with PAN-based PA sizing agent in step (2) by replacing the PAN-based PA sizing agent with PAN-based PA sizing agent in step (3) by replacing the PAN-based PA sizing agent ...3). The remaining parameters and steps are the same as in Example 3.

[0134] Example 26

[0135] This embodiment provides a carbon fiber modified polyketone composite material, which differs from Example 3 only in that the compatibilizer is maleic anhydride-grafted ethylene-octene copolymer, while the other parameters and steps are consistent with Example 3.

[0136] Example 27

[0137] This embodiment provides a carbon fiber modified polyketone composite material, which differs from Example 3 only in that the compatibilizer is maleic anhydride-grafted polypropylene copolymer, while the other parameters and steps are the same as in Example 3.

[0138] Example 28

[0139] This embodiment provides a carbon fiber modified polyketone composite material, which differs from Example 3 only in that the compatibilizer is maleic anhydride-grafted polyethylene copolymer, while the other parameters and steps are the same as in Example 3.

[0140] Example 29

[0141] This embodiment provides a carbon fiber modified polyketone composite material, which differs from Example 3 only in that the compatibilizer is methyl methacrylate grafted polyketone copolymer, while the other parameters and steps are the same as in Example 3.

[0142] Example 30

[0143] This embodiment provides a carbon fiber modified polyketone composite material, which differs from Example 3 only in that the compatibilizer is a methacrylic acid grafted polyketone copolymer, while the other parameters and steps are the same as in Example 3.

[0144] Example 31

[0145] This embodiment provides a carbon fiber modified polyketone composite material, which differs from Example 3 only in that the mixing and dispersion section combination is 32 / 32, 32 / 32, 32 / 32, 45° / 4 / 22, 45° / 4 / 22, 60° / 5 / 32, 22 / 22, 22 / 22, 22 / 22, ZME 8 / 16, ZME 8 / 16, while the remaining parameters and steps are consistent with Example 3.

[0146] Example 32

[0147] This embodiment provides a carbon fiber modified polyketone composite material, which differs from Example 3 only in that the mixing and dispersion section combination is 32 / 32, 45° / 4 / 22, 45° / 4 / 22, 60° / 5 / 32, 22 / 22, 22 / 22, 22 / 22, ZME 8 / 16, ZME 8 / 16, ZME 8 / 16, ZME 8 / 16, ZME 8 / 16, ZME 8 / 16, ZME 8 / 16. The remaining parameters and steps are consistent with those of Example 3.

[0148] Comparative Example 1

[0149] This comparative example provides a carbon fiber modified polyketone composite material, comprising, by weight parts: 77 parts of polyketone with a melt index of 200 g / 10 min, 20 parts of sheet-like KH550 / aramid nanofiber surface-modified carbon fiber short fibers (20 mm in length and 10 μm in diameter) with PAN-based PA sizing agent, 0.2 parts of antioxidant, 0.3 parts of external lubricant, 0.3 parts of internal lubricant, 0.1 parts of ultraviolet absorber, 3 parts of maleic anhydride-grafted carbon monoxide-ethylene-propylene polyketone copolymer compatibilizer, and 0.5 parts of anti-fiber leakage agent. The preparation method includes:

[0150] (1) The raw and auxiliary materials such as polyketone with a melt index of 200g / 10min, antioxidant, external lubricant, internal lubricant, ultraviolet absorber, maleic anhydride grafted carbon monoxide-ethylene-propylene polyketone copolymer compatibilizer, and anti-floating fiber leakage agent are weighed according to the proportion and added to the high-speed mixer. After mixing, a premix is ​​obtained.

[0151] (2) Add the premixed material to the main feed hopper of the twin-screw extruder, and at the same time add the sheet-like carbon fiber short fibers of PAN-based PA sizing agent to the hopper of the forced side feeder. The ratio of main feeder to side feeder is 80:20. Perform melt blending and extrusion to obtain carbon fiber modified polyketone composite material. The twin-screw extruder has a screw length-to-diameter ratio of 44:1 and a screw diameter D of 35mm. The screw components are arranged sequentially as follows: conveying section, melting and plasticizing section, side-feeding section, mixing and dispersing section, venting section, and metering and homogenizing section. The conveying section configurations are 32 / 32A, 48 / 48, 48 / 48, 32 / 32, 32 / 32, 32 / 32, 32 / 32, 32 / 32, and 32 / 32, with a processing temperature of 160℃. The melting and plasticizing section configurations are 90° / 5 / 32, 90° / 5 / 32, 32 / 32, 32 / 32, 22 / 22, 22 / 22, 22 / 22, and 22. / 22, 22 / 22, 22 / 22, 22 / 22, 32 / 32, 32 / 32, 90° / 5 / 32, 90° / 5 / 32, 22 / 11, processing temperature is 235℃, side material section combination is 48 / 48, 48 / 48, 48 / 48, 32 / 32, 48 / 48, 48 / 48, 48 / 48, processing temperature is 230℃, mixing and dispersing section combination is 32 / 32, 32 / 32, 45° / 4 / 22, 45° / 4 / 22, 60° / 5 / 32, 22 / 22, 22 / 22, 22 / 22, ZME 8 / 16, ZME 8 / 16, ZME 8 / 16, ZME 8 / 16, processing temperature is 220℃, exhaust section combination is 48 / 48, 48 / 48, 32 / 32, processing temperature is 230℃, metering homogenization section combination is 32 / 32, 32 / 32, 32 / 32, 32 / 32, 22 / 22, processing temperature is 235℃, and die head temperature is 200℃.

[0152] Comparative Example 2

[0153] This comparative example provides a carbon fiber modified polyketone composite material, comprising, by weight parts: 77 parts of polyketone with a melt index of 200 g / 10 min, 20 parts of sheet-like KH550 / aramid nanofiber surface-modified carbon fiber short fibers (20 mm in length and 10 μm in diameter) with PAN-based PA sizing agent, 0.2 parts of antioxidant, 0.3 parts of external lubricant, 0.3 parts of internal lubricant, 0.1 parts of ultraviolet absorber, 3 parts of maleic anhydride-grafted carbon monoxide-ethylene-propylene polyketone copolymer compatibilizer, and 0.5 parts of anti-fiber leakage agent. The preparation method includes:

[0154] (1) The raw and auxiliary materials such as polyketone with a melt index of 200g / 10min, antioxidant, external lubricant, internal lubricant, ultraviolet absorber, maleic anhydride grafted carbon monoxide-ethylene-propylene polyketone copolymer compatibilizer, and anti-floating fiber leakage agent are weighed according to the proportion and added to the high-speed mixer. After mixing, a premix is ​​obtained.

[0155] (2) Add the premixed material to the main feed hopper of the twin-screw extruder, and at the same time add the sheet-like carbon fiber short fibers of PAN-based PA sizing agent to the hopper of the forced side feeder. The ratio of main feeder to side feeder is 80:20. Perform melt blending and extrusion to obtain carbon fiber modified polyketone composite material. The twin-screw extruder has a screw length-to-diameter ratio of 44:1 and a screw diameter D of 35mm. The screw components are arranged sequentially as follows: conveying section, melting and plasticizing section, side-feeding section, mixing and dispersing section, venting section, and metering and homogenizing section. The conveying section configurations are 32 / 32A, 48 / 48, 48 / 48, 32 / 32, 32 / 32, 32 / 32, 32 / 32, 32 / 32, and 32 / 32, with a processing temperature of 160℃. The melting and plasticizing section configurations are 90° / 5 / 32, 90° / 5 / 32, 32 / 32, 32 / 32, 22 / 22, 22 / 22, 22 / 22, and 22. / 22, 22 / 22, 22 / 22, 22 / 22, 32 / 32, 32 / 32, 90° / 5 / 32, 90° / 5 / 32, 22 / 11, processing temperature is 235℃, side material section combination is 48 / 48, 48 / 48, 48 / 48, 32 / 32, 48 / 48, 48 / 48, 48 / 48, processing temperature is 230℃, mixing and dispersing section combination is 32 / 32, 32 / 32, 45° / 4 / 22, 45° / 4 / 22, 60° / 5 / 32, 22 / 22, 22 / 22, 22 / 22, ZME 8 / 16, ZME 8 / 16, ZME 8 / 16, ZME 8 / 16, processing temperature is 250℃, exhaust section combination is 48 / 48, 48 / 48, 32 / 32, processing temperature is 230℃, metering homogenization section combination is 32 / 32, 32 / 32, 32 / 32, 32 / 32, 22 / 22, processing temperature is 235℃, and die head temperature is 200℃.

[0156] Comparative Example 3

[0157] This comparative example provides a carbon fiber modified polyketone composite material, comprising, by weight parts: 77 parts of polyketone with a melt index of 200 g / 10 min, 20 parts of sheet-like KH550 / aramid nanofiber surface-modified carbon fiber short fibers (6 mm in length and 10 μm in diameter) with PAN-based PA sizing agent, 0.2 parts of antioxidant, 0.3 parts of external lubricant, 0.3 parts of internal lubricant, 0.1 parts of ultraviolet absorber, 3 parts of maleic anhydride-grafted carbon monoxide-ethylene-propylene polyketone copolymer compatibilizer, and 0.5 parts of anti-fiber leakage agent. The preparation method includes:

[0158] (1) The raw and auxiliary materials such as polyketone with a melt index of 200g / 10min, antioxidant, external lubricant, internal lubricant, ultraviolet absorber, maleic anhydride grafted carbon monoxide-ethylene-propylene polyketone copolymer compatibilizer, and anti-floating fiber leakage agent are weighed according to the proportion and added to the high-speed mixer. After mixing, a premix is ​​obtained.

[0159] (2) Add the premix to the main feed hopper of the twin-screw extruder, and at the same time add the sheet-like carbon fiber short fibers of PAN-based PA sizing agent with a length of 6 mm and a diameter of 10 μm to the hopper of the forced side feeder. The ratio of the main feeder to the side feeder is 80:20. Melt blend and extrusion are carried out to obtain carbon fiber modified polyketone composite material. The twin-screw extruder has a screw length-to-diameter ratio of 44:1 and a screw diameter D of 35mm. The screw components are arranged sequentially as follows: conveying section, melting and plasticizing section, side-feeding section, mixing and dispersing section, venting section, and metering and homogenizing section. The conveying section configurations are 32 / 32A, 48 / 48, 48 / 48, 32 / 32, 32 / 32, 32 / 32, 32 / 32, 32 / 32, 32 / 32, with a processing temperature of 160℃. The melting and plasticizing section configurations are 90° / 5 / 32, 90° / 5 / 32, 32 / 32, 32 / 32, 22 / 22, 22 / 22, 22 / 22, 22 / 22, 22 / 22, 22 / 22, 22 / 22, 22 / 22, 32 / 32, 32 / 32, 90° / 5 / 32, 90° / 5 / 32, 22 / 1 1. The processing temperature is 235℃. The side material section combination is 48 / 48, 48 / 48, 48 / 48, 32 / 32, 48 / 48, 48 / 48, 48 / 48, with a processing temperature of 230℃. The mixing and dispersing section combination is 32 / 32, 32 / 32, 45° / 4 / 22, 45° / 4 / 22, 60° / 5 / 32, 22 / 22, 22 / 22, 22 / 22, 32 / 32, 32 / 32, with a processing temperature of 220℃. The exhaust section combination is 48 / 48, 48 / 48, 32 / 32, with a processing temperature of 230℃. The metering and homogenization section combination is 32 / 32, 32 / 32, 32 / 32, 32 / 32, 22 / 22, with a processing temperature of 235℃. The die head temperature is 200℃.

[0160] Comparative Example 4

[0161] This comparative example provides a carbon fiber modified polyketone composite material, comprising, by weight parts: 77 parts of polyketone with a melt index of 200 g / 10 min, 20 parts of sheet-like KH550 / aramid nanofiber surface-modified carbon fiber short fibers (20 mm in length and 10 μm in diameter) with PAN-based PA sizing agent, 0.2 parts of antioxidant, 0.3 parts of external lubricant, 0.3 parts of internal lubricant, 0.1 parts of ultraviolet absorber, 3 parts of maleic anhydride-grafted carbon monoxide-ethylene-propylene polyketone copolymer compatibilizer, and 0.5 parts of anti-fiber leakage agent. The preparation method includes:

[0162] (1) Weigh the raw and auxiliary materials such as 200g / 10min polyketone, antioxidant, external lubricant, internal lubricant, ultraviolet absorber, maleic anhydride grafted carbon monoxide-ethylene-propylene polyketone copolymer compatibilizer, anti-floating fiber leakage agent and PAN-based PA sizing agent and sheet carbon fiber short fiber according to the proportion and add them into the high-speed mixer. After mixing, a premix is ​​obtained.

[0163] (2) The premixed material is added to the main feed hopper of a twin-screw extruder for melt blending and extrusion to obtain carbon fiber modified polyketone composite material. The twin-screw extruder has a screw length-to-diameter ratio of 44:1 and a screw diameter D of 35 mm. The screw components are arranged in sequence as follows: conveying section, melt plasticizing section, side material section, mixing and dispersing section, venting section, and metering and homogenizing section. The conveying section is arranged in the following configurations: 32 / 32A, 48 / 48, 48 / 48, 32 / 32, 32 / 32, 32 / 32, 32 / 32, 32 / 32, 32 / 32, with a processing temperature of 160℃. The melt plasticizing section is arranged in the following configurations: 90° / 5 / 32, 90° / 5 / 32, 32 / 32, 32 / 32, 22 / 22, 22 / 22, 22 / 22, 22 / 22, 22 / 22, 22 / 22, 22 / 22, 32 / 32, 32 / 32, 90° / 5 / 32, 90° / 5 / 32, 22 / 11, processing temperature is 235℃, side material section combination is 48 / 48, 48 / 48, 48 / 48, 32 / 32, 48 / 48, 48 / 48, 48 / 48, processing temperature is 230℃, mixing and dispersing section combination is 32 / 32, 32 / 32, 45° / 4 / 22, 45° / 4 / 22, 60° / 5 / 32, 22 / 22, 22 / 22, 22 / 22, ZME 8 / 16, ZME 8 / 16, ZME 8 / 16, ZME8 / 16, processing temperature is 220℃, exhaust section combination is 48 / 48, 48 / 48, 32 / 32, processing temperature is 230℃, metering homogenization section combination is 32 / 32, 32 / 32, 32 / 32, 32 / 32, 22 / 22, processing temperature is 235℃, and die head temperature is 200℃.

[0164] Comparative Example 5

[0165] This embodiment provides a carbon fiber modified polyketone composite material, comprising, by weight, 77 parts of polyketone with a melt index of 200 g / 10min, 20 parts of sheet-like KH550 / aramid nanofiber surface-modified carbon fiber short fibers (6 mm in length and 6 μm in diameter) with PAN-based PA sizing agent, 0.2 parts of antioxidant, 0.3 parts of external lubricant, 0.3 parts of internal lubricant, 0.1 parts of ultraviolet absorber, 3 parts of maleic anhydride-grafted carbon monoxide-ethylene-propylene polyketone copolymer compatibilizer, and 0.5 parts of anti-floating fiber leakage agent, wherein the mass ratio of aramid nanofibers to KH550 in the KH550 / aramid nanofiber modified dispersion is 0.5:1. The preparation method of the carbon fiber modified polyketone composite material includes:

[0166] (1) The raw and auxiliary materials such as polyketone, antioxidant, external lubricant, internal lubricant, ultraviolet absorber, maleic anhydride grafted carbon monoxide-ethylene-propylene polyketone copolymer compatibilizer, and anti-floating fiber leakage agent are weighed according to the proportion and added to the high-speed mixer. After mixing, a premix is ​​obtained.

[0167] (2) The premixed material is added to the main feed hopper of the twin-screw extruder, while the sheet-like carbon fiber short fibers of the PAN-based PA sizing agent are added to the forced side feeder hopper. The ratio of the main feeder to the side feeder is 80:20. Melt blending and extrusion are then performed to obtain the carbon fiber modified polyketide composite material. The screw length-to-diameter ratio of the twin-screw extruder is 44:1, and the screw diameter D is 35 mm. mm; the screw element assembly consists of a conveying section, a melting and plasticizing section, a side-positioning material section, a mixing and dispersing section, a venting section, and a metering and homogenizing section. The conveying section configurations are 32 / 32A, 48 / 48, 48 / 48, 32 / 32, 32 / 32, 32 / 32, 32 / 32, 32 / 32, with a processing temperature of 160℃. The melting and plasticizing section configurations are 90° / 5 / 32, 90° / 5 / 32, 32 / 32, 32 / 32, 22 / 22, 22 / 22, 22 / 22, 22 / 22, 22 / 22, 22 / 22, 22 / 22, 22 / 22, 22 / 22, 22 / 22, 22 / 22, 32 / 32, 32 / 32, 90° / 5 / 32, 90° / 5 / 32, 22 / 11, processing temperature is 235℃, side material section combination is 48 / 48, 48 / 48, 48 / 48, 32 / 32, 48 / 48, 48 / 48, 48 / 48, processing temperature is 230℃, mixing and dispersing section combination is 32 / 32, 32 / 32, 45° / 4 / 22, 45° / 4 / 22, 60° / 5 / 32, 22 / 22, 22 / 22, 22 / 22, ZME 8 / 16, ZME 8 / 16, ZME 8 / 16, ZME 8 / 16, processing temperature is 220℃, exhaust section combination is 48 / 48, 48 / 48, 32 / 32, processing temperature is 230℃, metering homogenization section combination is 32 / 32, 32 / 32, 32 / 32, 32 / 32, 22 / 22, processing temperature is 235℃, and die head temperature is 200℃.

[0168] The performance of the carbon fiber modified polyketone composite materials provided in Examples 1-32 and Comparative Examples 1-5 was tested using the following methods:

[0169] (1) Tensile modulus of elasticity and tensile strength test:

[0170] According to GB / T 1040.2 standard, the tensile speed is 100 mm / min;

[0171] (2) Flexural modulus of elasticity and flexural strength test:

[0172] According to GB / T 9341 standard, the test speed is 2 mm / min and the deflection is 16 mm.

[0173] (3) Impact strength test:

[0174] According to GB / T 1843 standard, the pendulum weight is 2.75J.

[0175] (4) Load deformation temperature:

[0176] Tested according to GB / T 1634.1 standard, 1.8MPa load;

[0177] (5) Melt index:

[0178] Tested according to GB / T 3682 standard, 240℃, 2.16kg.

[0179] The test results are shown in Table 1-2.

[0180] Table 1

[0181]

[0182] Table 2

[0183]

[0184] According to the data from Examples 1-32 in Tables 1-2, the mechanical strength of the carbon fiber modified polyketone composite material increases with the increase of carbon fiber short fiber content. The compatibilizer maleic anhydride grafted carbon monoxide-ethylene-propylene polyketone copolymer significantly affects the physical properties of the composite material, mainly due to the reinforcing effect of carbon fiber and high interfacial bonding strength, resulting in significant improvement in mechanical properties such as tensile strength, flexural strength, and elastic modulus.

[0185] Comparing the data from Examples 1-32 with those from Comparative Examples 1-4, the composite materials prepared in these examples exhibit higher mechanical strength. This is attributed to the coating containing active groups on the carbon fiber surface, and the presence of reactive functional groups on the surface of the silane coupling agent KH550 that can chemically react or strongly interact with the polyketide compatibilizer. During melt blending, the aramid nanofiber material acts as a "molecular bridge," with one end bonded to the active groups on the carbon fiber coating via its surface reactive functional groups, while the other end is physically entangled or embedded in the POK matrix through hydrogen bonding, thus constructing a strongly chemically bonded interfacial transition layer between the carbon fiber and the POK matrix. A large number of "bridging points" form a three-dimensional mechanically interlocked network structure of "aramid nanofiber-carbon fiber-POK resin" that runs through the entire structure. The uniformly dispersed aramid nanofibers and the formed three-dimensional network structure act as "physical crosslinking points" for the POK melt, improving melt strength and elasticity, enabling the composite material to maintain good processing rheology over a wider temperature and shear rate range, and reducing the risk of degradation.

[0186] Simultaneously, through optimized selection of POK resin, compatibilizer, and modified carbon fiber short fibers, and the design of the twin-screw extruder screw element combination and side-feeding process (especially the combination of ZME elements in the mixing and dispersion section), the dispersion and distribution uniformity of carbon fibers in POK resin were significantly improved, greatly enhancing interfacial compatibility and stress transfer efficiency while maintaining the effective fiber length, fundamentally solving the interfacial debonding problem. This structure allows heat to be rapidly transferred and dispersed through carbon fibers, and the enhanced interfacial bonding can resist high-temperature deformation, thereby significantly improving the heat resistance of the composite material.

[0187] Heat resistance tests (heating from 25°C to 800°C at a rate of 10°C / min under nitrogen protection) showed that the temperature at which the composites of Examples 1-32 lost 5% of their weight (T5%) was 25-40°C higher than that of the control examples, and the maximum thermogravimetric peak temperature (Tmaximum thermogravimetric peak) was increased by 30°C, indicating a significant increase in processing temperature. While maintaining excellent mechanical properties, this application effectively mitigates the thermal degradation of the polyketone backbone and improves the dispersion and distribution of carbon fibers in the resin, maintaining their effective length, through optimization of formulation and process parameters. This results in more stable melt flow during POK resin processing, controlled shear heat generation, and ultimately improved processing rheological behavior of the composite material, broadening its processing window. This application provides an innovative and effective solution for preparing high-performance, easily processable polyketone composites.

[0188] The above description is merely a preferred embodiment of this application, but the scope of protection of this application is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in this application, based on the technical solution and application concept of this application, should be included within the scope of protection of this application.

Claims

1. A method for preparing a carbon fiber modified polyketone composite material, characterized in that, include: Polyketone, compatibilizer and additives are mixed to obtain a premix; The premixed material is added to the main feed hopper of a twin-screw extruder, and the modified carbon fiber short fibers are added to the hopper of a forced side feeder. The mixture is then melt-extruded to obtain a carbon fiber modified polyketone composite material. The processing temperature of the melt extrusion is 140~160℃ in the conveying section, 220~235℃ in the melt plasticizing section, 220~230℃ in the side material section, 220~230℃ in the mixing and dispersing section, 220~230℃ in the venting section, 220~230℃ in the metering and homogenizing section, and 180~200℃ in the die head temperature. The mass ratio of polyketone, modified carbon fiber short fiber, compatibilizer and additives is (50~100):(5~50):(1-5):(0.5~5).

2. The preparation method according to claim 1, characterized in that, The polyketone is a ternary copolymer of carbon monoxide, ethylene and propylene, an aliphatic polyketone, with a melt index of 10 g / 10 min to 1000 g / 10 min at 240°C.

3. The preparation method according to claim 1, characterized in that, The modified carbon fiber short fiber is obtained by impregnating and modifying carbon fiber short fiber with a modified dispersion solution; The modified dispersion comprises a silane coupling agent and surface-modified nanomaterials; The mass ratio of the silane coupling agent to the surface-modified nanomaterial is (0.8~1.2):1; The silane coupling agent includes one or more of KH550, KH560, KH570 or titanate coupling agents; The carbon fiber short fibers include one or more of PAN-based carbon fibers, pitch-based carbon fibers, and viscose fiber-based carbon fibers; The modified carbon fiber short fibers have a length of 0.1 mm to 15 mm, a diameter of 3 μm to 30 μm, and an appearance shape of either cylindrical or sheet-like. The modified carbon fiber short fiber surface also includes a sizing agent layer, wherein the sizing agent includes one or more of polyamide, polyurethane, polyester, epoxy, phenolic, polyolefin, polyimide resin, nitrile rubber or styrene-butadiene rubber; The surface-modified nanomaterials include one or more of the following: aminated carbon nanotubes, carboxylated graphene, boehmite nanosheets modified with silane coupling agents, hydroxylated Mxene, or aramid nanofibers; the surface-modified nanomaterials have one-dimensional or two-dimensional nanostructures with an aspect ratio of 50 to 10000 and an average diameter of 1 nm to 1000 nm.

4. The preparation method according to claim 1, characterized in that, The compatibilizer includes one or more of the following: maleic anhydride-grafted ethylene-octene copolymer, maleic anhydride-grafted polyethylene copolymer, maleic anhydride-grafted polypropylene copolymer, maleic anhydride-grafted ethylene-butene copolymer, maleic anhydride-grafted carbon monoxide-ethylene polyketide copolymer, maleic anhydride-grafted carbon monoxide-ethylene-propylene polyketide copolymer, glycidyl methacrylate-grafted polyketide copolymer, methacrylic acid-grafted polyketide copolymer, acrylic acid-grafted polyketide copolymer, acrylamide-grafted polyketide copolymer, or methyl methacrylate-grafted polyketide copolymer.

5. The preparation method according to claim 1, characterized in that, The additives include one or more of antioxidants, external lubricants, internal lubricants, anti-fiber leakage agents, or ultraviolet absorbers; The mass ratio of the antioxidant, external lubricant, internal lubricant, anti-fiber leakage agent, and ultraviolet absorber is (0.1~0.5):(0.1~0.5):(0.1~0.5):(2~8):(0.2~0.8). The antioxidants include primary antioxidants and secondary antioxidants. The primary antioxidants include hindered phenolic antioxidants such as pentaerythritol tetrakis(3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, octadecyl-3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, and 2,6-di-tert-butyl-p-cresol. The product may contain one or more of 1,3,5-trimethyl-2,4,6-tris(3,5-di-tert-butyl-4-hydroxybenzyl)benzene; the auxiliary antioxidant may include one or more of the following phosphite antioxidants: tris(2,4-di-tert-butylphenyl) phosphite, dioctadecyl pentaerythritol diphosphite, bis(2,4-di-tert-butylphenyl) pentaerythritol diphosphite, diphenyl pentaerythritol diphosphite, or dilauryl thiodipropionate; the external lubricant may contain one or more of the following: polyethylene wax, polypropylene wax, Fischer-Tropsch wax, stearic acid, or stearic acid metal soap; the internal lubricant may contain one or more of the following: pentaerythritol stearate, butyl stearate, glyceryl monostearate, oleamide, erucamide, or ethylene bis-stearamide; the anti-fiber leakage agent may contain one or more of the following: modified polyethylene wax, acrylate copolymers, or polysiloxanes; and the ultraviolet absorber may contain UV-326, UV-327, or UV-329. Or one or more of the hindered amine light stabilizers 622.

6. The preparation method according to claim 1, characterized in that, The melt extrusion is carried out in a twin-screw extruder; The screw components in the twin-screw extruder are, in sequence, a conveying section, a melting and plasticizing section, a side-positioning material section, a mixing and dispersing section, a venting section, and a metering and homogenizing section.

7. The preparation method according to claim 6, characterized in that, The twin-screw extruder is a parallel co-rotating twin-screw extruder with a screw length-to-diameter ratio of 44:1 and a screw diameter D of 35 mm. The conveying section of the screw element in the twin-screw extruder is a forward conveying element, accounting for 10% to 20% of the length, with a lead of 16 to 96 mm and a pitch of 16 to 48 mm.

8. The preparation method according to claim 6, characterized in that, The melting and plasticizing section of the twin-screw extruder uses a combination of a tapered lead forward conveying screw element and kneading blocks, accounting for 20% to 35% of the length. The lead of the forward conveying screw element is 16 to 48 mm, and the pitch of the forward conveying screw element is 11 to 48 mm. The shear angle of the kneading blocks is 45° to 90°, and the number of blocks is 4 to 10. The pitch of the kneading blocks is 11 to 48 mm. The side section of the screw element in the twin-screw extruder adopts a forward conveying screw element, with a length ratio of 15% to 25%, a lead of 16 to 96 mm, and a pitch of 16 to 48 mm. The mixing and dispersing section of the twin-screw extruder screw element adopts a combination of a tapered lead forward conveying screw element, a kneading block, and a ZME strong dispersing element, accounting for 15% to 20% of the length. The forward conveying screw element has a lead of 16 to 48 mm and a pitch of 11 to 48 mm. The kneading block has a shear angle of 45° to 90° and consists of 4 to 8 blocks with a pitch of 11 to 48 mm. The ZME strong dispersing element has a lead of 4 to 22 mm and a pitch of 8 to 32 mm. The exhaust section of the twin-screw extruder uses a large-lead forward conveying screw element, accounting for 5% to 10% of the length, with a lead of 16 to 48 mm and a pitch of 11 to 48 mm. It is equipped with a vacuum exhaust port with a vacuum degree of -0.06 to -0.09 MPa.

9. The preparation method according to claim 6, characterized in that, The metering and homogenization section of the twin-screw extruder uses a forward-feeding screw element with a gradually decreasing lead, accounting for 5% to 15% of the length, with a lead of 16 to 48 mm and a pitch of 11 to 48 mm. The modified carbon fiber short fibers are fed into the extruder via a forced side feeder, and the feed screw adopts a parallel twin-screw structure.

10. A carbon fiber modified polyketone composite material, characterized in that, It is prepared according to the preparation method described in any one of claims 1 to 9.

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