A fiber-reinforced polyphenylene sulfide / polyamide composite, a method of making and a system for making
By grafting silane coupling agents and nano zinc oxide onto the fiber surface, combined with a four-segment independent temperature-controlled molding die and ultrasonic impregnation technology, the problem of weak bonding between PPS resin and fiber was solved, achieving efficient preparation of fiber-reinforced polyphenylene sulfide/polyamide composite materials and improving the mechanical properties and interfacial bonding strength of the materials.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- SINOMA SCI & TECH
- Filing Date
- 2026-06-03
- Publication Date
- 2026-07-31
AI Technical Summary
In the existing technology, PPS resin has a weak bond with fibers, and the PPS melt viscosity is extremely high, making it difficult to fully wet the fiber bundle in a short time. This results in defects such as dry spots and weak interfacial bonding in the products, which seriously affect the mechanical properties.
By grafting silane coupling agents and nano zinc oxide onto the fiber surface, a multifunctional nanoscale transition layer is constructed. Combined with a four-segment independent temperature-controlled molding die and ultrasonic impregnation technology, multiple chemical bridging and nano-anchoring effects between the fiber and resin are achieved, promoting heat transfer and crystallization control, and forming a through-interface architecture.
It significantly enhances the interfacial bonding strength between fibers and resins, improves the mechanical properties, toughness, and durability of composite materials, and enhances the dimensional stability and mechanical properties of the products.
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Figure CN122302330B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of polymer materials technology, and in particular to a fiber-reinforced polyphenylene sulfide / polyamide composite material, its preparation method and preparation system. Background Technology
[0002] Continuous fiber reinforced thermoplastic composites (CFRTPs) have broad application prospects in aerospace, automotive, and rail transportation fields due to their high specific strength, high specific modulus, recyclability, and good fatigue resistance.
[0003] Pultrusion is an efficient process for preparing linear CFRTP materials, but it faces significant challenges when handling high-viscosity, high-melting-point continuous fiber-reinforced polyphenylene sulfide / polyamide resin systems. The weak bond between PPS resin and fibers, coupled with the extremely high melt viscosity of PPS, makes it difficult to fully wet the fiber bundles in a short time, leading to defects such as dry spots and weak interfacial bonding in the finished product, severely impacting its mechanical properties.
[0004] Therefore, in view of the above problems, the present invention urgently needs to provide a fiber-reinforced polyphenylene sulfide / polyamide composite material, its preparation method and preparation system. Summary of the Invention
[0005] The purpose of this invention is to provide fiber-reinforced polyphenylene sulfide / polyamide composite materials, their preparation methods, and preparation systems. By proposing fiber-reinforced polyphenylene sulfide / polyamide composite materials and their preparation methods, this invention aims to solve the technical problems existing in the prior art, such as weak bonding between PPS resin and fibers, extremely high PPS melt viscosity, difficulty in fully wetting fiber bundles in a short time, resulting in defects such as dry spots and weak interfacial bonding in the products, which seriously affect the mechanical properties.
[0006] The present invention provides a method for preparing fiber-reinforced polyphenylene sulfide / polyamide composite material, comprising the following steps: The silane coupling agent and nano zinc oxide are mixed and stirred evenly, then grafted onto the fiber surface through impregnation or sizing processes, and dried to obtain modified fibers. According to the weight percentages, 30-50 parts of polyphenylene sulfide (PPS), 40-50 parts of polyamide 66 (PA66), 3-8 parts of compatibilizer, and 0.2-0.8 parts of antioxidant are mixed, melt-blended in a twin-screw extruder, extruded, cooled, and pelletized to obtain blended granules. The blended particles are heated and melted to obtain an impregnation solution; The modified fibers are drawn into the impregnation liquid and ultrasonically impregnated. The impregnated modified fibers are then drawn into four independent temperature-controlled molding molds and heated to obtain fiber-reinforced polyphenylene sulfide / polyamide composite materials. The four independent temperature-controlled molding dies are sequentially equipped with a first melting zone, a second transition zone, a third crystallization zone, and a fourth cooling zone, with temperatures set at 290-310℃, 230-250℃, 180-200℃, and 60-80℃ respectively, and a traction speed of 0.2-1.0 m / min.
[0007] Preferably, the amount of silane coupling agent added is 0.5%-3% of the fiber mass; the amount of nano zinc oxide added is 1%-5% of the fiber mass.
[0008] Preferably, the mass ratio of 30-50 parts of polyphenylene sulfide (PPS) to polyamide 66 (PA66) is 1:1.
[0009] Preferably, in ultrasonic impregnation, the ultrasonic frequency is 20-40 kHz, the power is 500-1500W, and the temperature of the impregnation solution is 290-310℃.
[0010] Preferably, the compatibilizer is maleic anhydride-grafted hydrogenated styrene-butadiene-styrene block copolymer (SEBS-g-MAH).
[0011] Preferably, the antioxidant is pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate].
[0012] Preferably, before mixing polyphenylene sulfide (PPS) and polyamide 66 (PA66), the mixture is vacuum dried at 100-120°C for 4-6 hours.
[0013] Preferably, the extrusion temperature of the twin-screw extruder is 250-290℃.
[0014] Preferably, the mass ratio of blended particles to fibers is (2-3):1; the fibers are carbon fibers or glass fibers.
[0015] The present invention also provides a fiber-reinforced polyphenylene sulfide / polyamide composite material obtained based on the fiber-reinforced polyphenylene sulfide / polyamide composite material preparation method as described in any one of the above.
[0016] This embodiment also provides a system for preparing fiber-reinforced polyphenylene sulfide / polyamide composites as described in any of the above embodiments, including... The wire guiding mechanism is used to transport fibers; A fiber surface treatment apparatus is used to treat the surface of fibers to obtain modified fibers; Impregnation mechanism, used for impregnating fibers with resin; Independent temperature-controlled molding die for heating the impregnated fibers; The cutting mechanism is used to cut the composite material conveyed by the independent temperature-controlled molding die; A blending and granulation mechanism for manufacturing blended granules; The glue impregnation mechanism includes a glue tank, and an ultrasonic transducer is fixed at the bottom of the glue tank.
[0017] The independent temperature-controlled molding die includes four heating zones.
[0018] The fiber-reinforced polyphenylene sulfide / polyamide composite material provided by this invention, its preparation method, and preparation system have the following advantages compared with the prior art: 1. The method for preparing fiber-reinforced polyphenylene sulfide / polyamide composite materials provided by this invention involves pre-treating the fiber surface and using silane coupling agents and nano-zinc oxide as modifiers. The nano-zinc oxide is coated with the silane coupling agent and chemically grafted onto the fiber surface to construct a multifunctional nanoscale transition layer. The silane coupling agent molecules first undergo hydrolysis to generate silanol groups. These silanol groups can undergo dehydration condensation reactions with the hydroxyl groups on the fiber surface (such as glass fiber, carbon fiber, etc.) to form strong -Si-O- covalent bonds. Simultaneously, the other end of the silane coupling agent is tightly bonded to the nano-zinc oxide surface through van der Waals forces or coordination bonds. The organic functional groups of the silane coupling agent can generate strong intermolecular interactions with the terminal amino or amide bonds on the polyamide 66 (PA66) molecular chain to form hydrogen bonds, and undergo amidation reactions to form covalent bonds. This achieves multiple chemical bridging of covalent bonds and hydrogen bonds from fiber to resin, greatly enhancing the interfacial chemical bonding strength. Nanoscale zinc oxide particles introduce nanoscale roughness onto the fiber surface. When the resin melt weeps in, it embeds itself into these nanoscale irregularities, forming a strong "nanoanchoring effect" after solidification. This significantly increases the contact area and friction between the fiber and the matrix, achieving multi-level mechanical interlocking from the macroscopic, microscopic to the nanoscale, effectively preventing interfacial debonding. Furthermore, during the cooling and crystallization stage of the composite material, the uniformly distributed nanoscale zinc oxide in the interfacial region can act as a heterogeneous nucleating agent. It can lower the nucleation barrier of polyphenylene sulfide (PPS) and PA66, inducing the resin to form a fine crystalline structure at the interface. This fine-grained structure not only improves the performance of the matrix itself but also forms a continuous "fiber-nanoparticle-crystal" structure that runs through the interface, making the interfacial bonding more compact and robust.
[0019] 2. The fiber-reinforced polyphenylene sulfide / polyamide composite material preparation method provided by the invention, through nano-zinc oxide and four independent temperature settings, can effectively improve the bonding strength between fibers and resin. The temperature of the first melting zone is set at 290-310℃, which can promote heat conduction and interface pre-wetting: nano-zinc oxide has high thermal conductivity and acts as a micro-conducting hot spot in the melting zone, promoting the transfer of heat from the resin melt to the interior of the fiber bundle, helping to eliminate impregnation blind zones caused by local low temperatures and ensuring overall impregnation uniformity. At the same time, at this high temperature, the intermolecular interactions (such as hydrogen bonds) between the organic functional groups (such as amino groups) of the silane coupling agent on its surface and the terminal amino groups or amide bonds of the polyamide 66 (PA66) melt are fully activated, initiating preliminary and effective interfacial chemical bridging. The second transition zone and the third crystallization zone are 230-250℃ and 180-200℃ respectively, which can induce heterogeneous nucleation and regulate crystal morphology. The nano zinc oxide particles provide abundant heterogeneous nucleation sites for the crystallization of polyphenylene sulfide (PPS) and PA66. This not only significantly refines the spherulite size of the resin, but more importantly, it forms a through-interface architecture with "fiber-nano zinc oxide-resin crystal" as the core, which elevates the interface bonding from physical anchoring to physicochemical synergistic bonding at the nanoscale.
[0020] 3. The method for preparing fiber-reinforced polyphenylene sulfide / polyamide composites provided by the invention utilizes the rigidity of nano-zinc oxide, which allows it to serve as an effective stress transfer point when the composite is under stress, efficiently transferring the load from the resin matrix to the reinforcing fibers. Simultaneously, its extensive interface with the matrix can induce crimping and plastic deformation in the matrix, thereby dissipating energy, blunting crack tips, and significantly preventing the initiation and propagation of microcracks at the interface, thus improving the toughness and durability of the composite material.
[0021] 4. The method for preparing fiber-reinforced polyphenylene sulfide / polyamide composite materials provided by the invention sets the temperature of the first melting zone to 290-310℃, which is higher than the melting points of PPS and PA66, ensuring that the resin maintains a low-viscosity molten state, completing the final wetting and removing air bubbles; the temperature of the second transition zone is set to 230-250℃, which is between the melting point of PPS (285℃) and its maximum crystallization temperature (140℃), and is an ideal overheated crystallization region. In this region, the PPS phase is induced to preferentially form crystal nuclei and begin to crystallize slowly; the temperature of the third crystallization zone is set to 180-200℃, which is lower than the maximum crystallization rate temperature of PA66, but still much higher than its glass transition temperature, and is within its effective crystallization temperature window. In this region, PA66 crystallizes in a controlled and relatively slow manner on the abundant heterogeneous nucleation sites provided by the PPS crystals pre-formed in the second transition zone. This process is conducive to the formation of a fine crystal structure and to the maximum release of internal stress generated during crystallization, thereby significantly improving the dimensional stability and mechanical properties of the product; the fourth cooling zone uses water cooling or air cooling to cool the profile to below 60-80℃, so that it is completely shaped.
[0022] 5. The fiber-reinforced polyphenylene sulfide / polyamide composite material preparation method provided by the present invention uses ultrasonic-assisted impregnation. The cavitation effect of ultrasound can effectively disperse the fiber bundles and significantly reduce the surface viscosity of the resin. At the same time, the acoustic flow effect can promote the flow and displacement of the resin in the fiber bundles, thereby achieving deep and rapid impregnation.
[0023] 6. The fiber-reinforced polyphenylene sulfide / polyamide composite material preparation method provided by the present invention has a fiber mass ratio of 16%-33% in the obtained fiber-reinforced polyphenylene sulfide / polyamide composite material, which makes the material have high mechanical properties. Attached Figure Description
[0024] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.
[0025] Figure 1 This is a scanning electron microscope image of the cross section of the fiber-reinforced polyphenylene sulfide / polyamide composite material obtained in Example 1; Figure 2 The image shows a scanning electron microscope (SEM) image of the cross-section of the fiber-reinforced polyphenylene sulfide / polyamide composite material obtained in Comparative Example 1. Figure 3 This is a schematic diagram of the preparation system for the fiber-reinforced polyphenylene sulfide / polyamide composite material described in this invention. Detailed Implementation
[0026] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.
[0027] This invention provides a method for preparing fiber-reinforced polyphenylene sulfide / polyamide composite materials, comprising the following steps: S1) Mix silane coupling agent and nano zinc oxide, stir evenly, graft onto fiber surface through impregnation or sizing process, and dry to obtain modified fiber; S2) By weight, 30-50 parts of polyphenylene sulfide (PPS), 40-50 parts of polyamide 66 (PA66), 3-8 parts of compatibilizer, and 0.2-0.8 parts of antioxidant are mixed, melt-blended in a twin-screw extruder, extruded, cooled, and pelletized to obtain blended granules. S3) The blended particles are heated and melted to obtain an impregnation solution; S4) The modified fiber is drawn into the impregnation liquid and ultrasonically impregnated. The impregnated modified fiber is drawn into a four-section independent temperature-controlled molding mold and heated to obtain a fiber-reinforced polyphenylene sulfide / polyamide composite material. The four independent temperature-controlled molding dies are sequentially equipped with a first melting zone, a second transition zone, a third crystallization zone, and a fourth cooling zone, with temperatures set at 290-310℃, 230-250℃, 180-200℃, and 60-80℃ respectively, and a traction speed of 0.2-1.0 m / min.
[0028] Specifically, the amount of silane coupling agent added is 0.5%-3% of the fiber mass; the amount of nano zinc oxide added is 1%-5% of the fiber mass.
[0029] Specifically, the mass ratio of 30-50 parts of polyphenylene sulfide (PPS) to polyamide 66 (PA66) is 1:1.
[0030] Specifically, in ultrasonic impregnation, the ultrasonic frequency is 20-40 kHz, the power is 500-1500W, and the temperature of the impregnation solution is 290-310℃.
[0031] Specifically, the compatibilizer is maleic anhydride-grafted hydrogenated styrene-butadiene-styrene block copolymer (SEBS-g-MAH).
[0032] Specifically, the antioxidant is pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate].
[0033] Specifically, before mixing polyphenylene sulfide (PPS) and polyamide 66 (PA66), the mixture is vacuum dried at 100-120°C for 4-6 hours.
[0034] Specifically, the extrusion temperature of the twin-screw extruder is 250-290℃.
[0035] Specifically, the mass ratio of blended particles to fibers is (2-3):1; the fibers are carbon fibers or glass fibers.
[0036] The present invention also provides a fiber-reinforced polyphenylene sulfide / polyamide composite material obtained based on the fiber-reinforced polyphenylene sulfide / polyamide composite material preparation method as described in any one of the above.
[0037] This invention provides a method for preparing fiber-reinforced polyphenylene sulfide / polyamide composites. Nano-zinc oxide is coated with a silane coupling agent and chemically grafted onto the fiber surface, constructing a multifunctional nanoscale transition layer. The silane coupling agent molecules first undergo hydrolysis to generate silanol groups. These silanol groups can undergo dehydration condensation reactions with the hydroxyl groups on the fiber surface (such as glass fiber, carbon fiber, etc.) to form strong -Si-O- covalent bonds. Simultaneously, the other end of the silane coupling agent is tightly bonded to the nano-zinc oxide surface through van der Waals forces or coordination bonds. The organic functional groups of the silane coupling agent can generate strong intermolecular interactions with the terminal amino or amide bonds on the polyamide 66 (PA66) molecular chain to form hydrogen bonds, and undergo amidation reactions to form covalent bonds. This achieves multiple chemical bridging of covalent and hydrogen bonds from fiber to resin, greatly enhancing the interfacial chemical bonding strength. Nanoscale zinc oxide particles introduce nanoscale roughness onto the fiber surface. When the resin melt weeps in, it embeds itself into these nanoscale irregularities, forming a strong "nanoanchoring effect" after solidification. This significantly increases the contact area and friction between the fiber and the matrix, achieving multi-level mechanical interlocking from the macroscopic, microscopic to the nanoscale, effectively preventing interfacial debonding. Furthermore, during the cooling and crystallization stage of the composite material, the uniformly distributed nanoscale zinc oxide in the interfacial region can act as a heterogeneous nucleating agent. It can lower the nucleation barrier of polyphenylene sulfide (PPS) and PA66, inducing the resin to form a fine crystalline structure at the interface. This fine-grained structure not only improves the performance of the matrix itself but also forms a continuous "fiber-nanoparticle-crystal" structure that runs through the interface, making the interfacial bonding more compact and robust.
[0038] The invention provides a method for preparing fiber-reinforced polyphenylene sulfide / polyamide composites. Through nano-zinc oxide and four independent temperature settings, the bonding strength between fibers and resin can be effectively improved. The first melting zone temperature is set at 290-310℃, which promotes heat conduction and interfacial pre-wetting. Nano-zinc oxide has high thermal conductivity and acts as a micro-hot spot in the melting zone, promoting heat transfer from the resin melt to the fiber bundle interior. This helps eliminate impregnation blind zones caused by localized low temperatures, ensuring overall impregnation uniformity. Simultaneously, at this high temperature, the intermolecular interactions (such as hydrogen bonds) between the organic functional groups (e.g., amino groups) of the surface silane coupling agent and the terminal amino or amide bonds of the polyamide 66 (PA66) melt are fully activated, initiating preliminary and effective interfacial chemical bridging. The second transition zone and the third crystallization zone are 230-250℃ and 180-200℃ respectively, which can induce heterogeneous nucleation and regulate crystal morphology. The nano zinc oxide particles provide abundant heterogeneous nucleation sites for the crystallization of polyphenylene sulfide (PPS) and PA66. This not only significantly refines the spherulite size of the resin, but more importantly, it forms a through-interface architecture with "fiber-nano zinc oxide-resin crystal" as the core, which elevates the interface bonding from physical anchoring to physicochemical synergistic bonding at the nanoscale.
[0039] The invention provides a method for preparing fiber-reinforced polyphenylene sulfide / polyamide composites. The rigidity of nano-zinc oxide allows it to act as an effective stress transfer point when the composite is under stress, efficiently transferring the load from the resin matrix to the reinforcing fibers. Simultaneously, its extensive interface with the matrix can induce crimping and plastic deformation in the matrix, thereby dissipating energy, blunting crack tips, and significantly preventing the initiation and propagation of microcracks at the interface, thus improving the toughness and durability of the composite material.
[0040] The invention provides a method for preparing fiber-reinforced polyphenylene sulfide / polyamide composite materials. The first melting zone temperature is set at 290-310℃, higher than the melting points of PPS and PA66, ensuring the resin remains in a low-viscosity molten state to complete final wetting and remove air bubbles. The second transition zone temperature is set at 230-250℃, which is between the melting point of PPS (285℃) and its maximum crystallization temperature (140℃), making it an ideal overheated crystallization region. In this region, the PPS phase is induced to preferentially form crystal nuclei and begin slow crystallization. The third crystallization zone temperature is set at 180-200℃. Although this temperature is lower than the maximum crystallization rate temperature of PA66, it is still much higher than its glass transition temperature, falling within its effective crystallization temperature window. In this region, PA66 undergoes controlled and relatively slow crystallization on the abundant heterogeneous nucleation sites provided by the PPS crystals pre-formed in the second transition zone. This process is conducive to the formation of a fine crystal structure and to the maximum release of internal stress generated during crystallization, thereby significantly improving the dimensional stability and mechanical properties of the product; the fourth cooling zone uses water cooling or air cooling to cool the profile to below 60-80℃, so that it is completely shaped.
[0041] like Figure 3 As shown, the present invention also provides a system for preparing fiber-reinforced polyphenylene sulfide / polyamide composites as described above, comprising: Conductor mechanism 1 is used to transport fibers; Fiber surface treatment unit 2 is used to treat the fiber surface to obtain modified fibers; Impregnation mechanism 4 is used to impregnate the fibers with resin. Independent temperature-controlled molding die 5 is used to heat the impregnated fibers; Cutting mechanism 6 is used to cut the composite material conveyed by the independent temperature-controlled molding die; 3 is a blending and granulation unit used for manufacturing blended granules; The glue impregnation mechanism 4 includes a glue tank, and an ultrasonic transducer is fixed at the bottom of the glue tank.
[0042] The independent temperature-controlled molding die includes four heating zones.
[0043] The four heating zones are, in order, the first melting zone 501, the second transition zone 502, the third crystallization zone 503, and the fourth cooling zone 504.
[0044] Example 1 This embodiment provides a method for preparing fiber-reinforced polyphenylene sulfide / polyamide composite materials, including the following steps: 101) Mix silane coupling agent and nano zinc oxide, stir evenly, graft onto fiber surface through impregnation process, and dry to obtain modified fiber; specifically, add silane coupling agent into container, slowly add nano zinc oxide powder under stirring, stir until no obvious large agglomerates are found, obtain mixed slurry, transfer mixed slurry to high-speed disperser, shear disperse at 4000 r / min for 12 min to initially deagglomerate nano zinc oxide agglomerates; place the high-speed dispersed mixed slurry in ultrasonic dispersion equipment, ultrasonically treat at 40 kHz and 500 W for 30 min to fully dissociate and uniformly disperse nano zinc oxide in silane coupling agent to obtain modified liquid; The fiber was drawn into the modification solution, immersed for 60 seconds, and dried at 90°C for 8 minutes to obtain the modified fiber. 102) According to the weight parts, 30 parts of polyphenylene sulfide (PPS), 40 parts of polyamide 66 (PA66), 3 parts of compatibilizer and 0.2 parts of antioxidant are mixed, melt-blended in a twin-screw extruder, extruded, cooled and pelletized to obtain blended granules; 103) The blended particles are heated and melted to obtain an impregnation solution; 104) The modified fiber is drawn into the impregnation liquid and ultrasonically impregnated. The impregnated modified fiber is drawn into a four-section independent temperature-controlled molding mold and heated to obtain fiber-reinforced polyphenylene sulfide / polyamide composite material. The four independent temperature-controlled molding dies are sequentially equipped with a first melting zone, a second transition zone, a third crystallization zone, and a fourth cooling zone, with temperatures set at 290℃, 230℃, 180℃, and 60℃ respectively, and a traction speed of 0.2 m / min.
[0045] In this embodiment, the amount of silane coupling agent added is 0.5% of the fiber mass; the amount of nano zinc oxide added is 1% of the fiber mass.
[0046] In this embodiment of ultrasonic impregnation, the ultrasonic frequency is 20 kHz, the power is 500 W, and the temperature of the impregnation solution is 290°C.
[0047] The compatibilizer in this embodiment is maleic anhydride-grafted hydrogenated styrene-butadiene-styrene block copolymer (SEBS-g-MAH).
[0048] The antioxidant in this embodiment is pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate].
[0049] The silane coupling agent in this embodiment is KH550.
[0050] Before mixing the polyphenylene sulfide (PPS) and polyamide 66 (PA66) in this embodiment, the mixture was vacuum dried at 100°C for 4 hours.
[0051] The extrusion temperature of the twin-screw extruder in this embodiment is 250°C.
[0052] In this embodiment, the mass ratio of blended particles to fibers is 2:1.
[0053] The fiber is carbon fiber.
[0054] The physical properties of the fiber-reinforced polyphenylene sulfide / polyamide composite material obtained in this embodiment are shown in Table 1.
[0055] The cross-section of the fiber-reinforced polyphenylene sulfide / polyamide composite material obtained in this embodiment is shown in the figure. Figure 1 , Figure 1 The fiber exhibits good wettability and the resin is tightly bonded to the fiber.
[0056] Example 2 This embodiment provides a method for preparing fiber-reinforced polyphenylene sulfide / polyamide composite materials, including the following steps: 201) Mix silane coupling agent and nano zinc oxide, stir evenly, graft onto fiber surface through impregnation process, dry to obtain modified fiber, the preparation process is the same as in Example 1; 202) By weight, 50 parts of polyphenylene sulfide (PPS), 50 parts of polyamide 66 (PA66), 8 parts of compatibilizer, and 0.8 parts of antioxidant are mixed, melt-blended in a twin-screw extruder, extruded, cooled, and pelletized to obtain blended granules; 203) The blended particles are heated and melted to obtain an impregnation solution; 204) The modified fiber is drawn into the impregnation liquid and ultrasonically impregnated. The impregnated modified fiber is drawn into a four-section independent temperature-controlled molding mold and heated to obtain fiber-reinforced polyphenylene sulfide / polyamide composite material. The four independent temperature-controlled molding dies are sequentially equipped with a first melting zone, a second transition zone, a third crystallization zone, and a fourth cooling zone, with temperatures set at 310℃, 250℃, 200℃, and 80℃ respectively, and a traction speed of 1.0 m / min.
[0057] In this embodiment, the amount of silane coupling agent added is 3% of the fiber mass; the amount of nano zinc oxide added is 5% of the fiber mass.
[0058] In this embodiment of ultrasonic impregnation, the ultrasonic frequency is 40 kHz, the power is 1500W, and the temperature of the impregnation solution is 310℃.
[0059] The compatibilizer in this embodiment is maleic anhydride-grafted hydrogenated styrene-butadiene-styrene block copolymer (SEBS-g-MAH).
[0060] The silane coupling agent in this embodiment is KH550.
[0061] The antioxidant in this embodiment is pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate].
[0062] Before mixing the polyphenylene sulfide (PPS) and polyamide 66 (PA66) in this embodiment, the mixture was vacuum dried at 120°C for 6 hours.
[0063] The extrusion temperature of the twin-screw extruder in this embodiment is 290°C.
[0064] In this embodiment, the mass ratio of blended particles to fibers is 3:1; the fibers are glass fibers.
[0065] Comparative Example 1 The only difference between this comparative example and Example 1 is that the fiber surface modifier does not contain nano zinc oxide. The other steps are the same as in Example 1. The properties of the obtained fiber-reinforced polyphenylene sulfide / polyamide composite material are shown in Table 1.
[0066] Since no nano-zinc oxide was added in this comparative example, compared with Example 1, the fiber-reinforced polyphenylene sulfide / polyamide composite material showed a decrease in tensile strength and flexural strength, a decrease in heat distortion temperature, and an increase in warpage.
[0067] like Figure 2 As shown, compared to Example 1, the fiber-resin bonding in this comparative example is poor, and the resin matrix around the fiber has pore defects.
[0068] Based on the above analysis, it is evident that the addition of nano zinc oxide not only enhances interfacial bonding through "nano-anchoring" and heterogeneous nucleation, but also helps to improve the thermal and dimensional stability of the composite material.
[0069] Comparative Example 2 The only difference between this comparative example and Example 1 is the temperature setting of the four independent temperature control zones. The temperatures of the first melting zone, the second transition zone, the third crystallization zone, and the fourth cooling zone are set to 280°C, 190°C, 150°C, and 60°C, respectively. The other steps are the same as in Example 1. The properties of the obtained fiber-reinforced polyphenylene sulfide / polyamide composite material are shown in Table 1.
[0070] Compared to Example 1, the heating temperatures of the first melting zone, second transition zone, third crystallization zone, and fourth cooling zone in this comparative example are lower than those in Example 1. The fiber-reinforced polyphenylene sulfide / polyamide composite material obtained in this comparative example shows a decrease in tensile strength and flexural strength, a decrease in heat distortion temperature, and a significant increase in warpage. It can be seen that the optimized four-stage independent temperature control process, by precisely controlling the crystallization behavior of the resin and the release of internal stress, is the key to obtaining a low-warpage, high-heat-resistant composite material.
[0071] Comparative Example 3 The only difference between this comparative example and Example 1 is the absence of a compatibilizer; the other steps are the same as in Example 1. The obtained fiber-reinforced polyphenylene sulfide / polyamide composite material is shown in Table 1.
[0072] Compared to Example 1, due to the absence of compatibilizer, the mechanical properties of the fiber-reinforced polyphenylene sulfide / polyamide composite material obtained in this comparative example are significantly reduced, with a decrease in heat distortion temperature and an increase in warpage.
[0073] This indicates that compatibilizers can effectively improve the compatibility and interfacial adhesion between the two phases of PPS and PA66, and are indispensable for obtaining composite materials with balanced performance.
[0074] Comparative Example 4 The only difference between this comparative example and Example 1 is that there is no ultrasonic-assisted impregnation. The other steps are the same as in Example 1. The obtained fiber-reinforced polyphenylene sulfide / polyamide composite material is shown in Table 1.
[0075] Compared to Example 1, the mechanical properties of the fiber-reinforced polyphenylene sulfide / polyamide composite material obtained in this comparative example decreased significantly due to the lack of ultrasonic-assisted impregnation. The heat distortion temperature decreased and the warpage increased. It can be seen that the ultrasonic-assisted impregnation process can effectively ensure the rapid and deep wetting of the resin into the fiber bundle, which is an important guarantee for reducing internal defects and obtaining homogeneous high-performance composite materials.
[0076] Table 1. Performance test results of fiber-reinforced polyphenylene sulfide / polyamide composites
[0077] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.
Claims
1. A process for the production of a fiber-reinforced polyphenylene sulfide / polyamide composite material, characterized by: Includes the following steps: The silane coupling agent and nano zinc oxide are mixed and stirred evenly, then grafted onto the fiber surface through impregnation or sizing processes, and dried to obtain modified fibers. According to the weight percentages, 30-50 parts of polyphenylene sulfide (PPS), 40-50 parts of polyamide 66 (PA66), 3-8 parts of compatibilizer, and 0.2-0.8 parts of antioxidant are mixed, melt-blended in a twin-screw extruder, extruded, cooled, and pelletized to obtain blended granules. The blended particles are heated and melted to obtain an impregnation solution; The modified fibers are drawn into the impregnation liquid and ultrasonically impregnated. The impregnated modified fibers are then drawn into four independent temperature-controlled molding molds and heated to obtain fiber-reinforced polyphenylene sulfide / polyamide composite materials. The four independent temperature-controlled molding dies are sequentially equipped with a first melting zone, a second transition zone, a third crystallization zone, and a fourth cooling zone, with temperatures set at 290-310℃, 230-250℃, 180-200℃, and 60-80℃ respectively, and a traction speed of 0.2-1.0m / min. The amount of silane coupling agent added is 0.5%-3% of the fiber mass; the amount of nano zinc oxide added is 1%-5% of the fiber mass. The mass ratio of blended particles to fibers is (2-3):1; the fibers are carbon fiber or glass fiber.
2. The process for the preparation of a fiber reinforced polyphenylene sulfide / polyamide composite according to claim 1, characterized in that: The mass ratio of polyphenylene sulfide (PPS) to polyamide 66 (PA66) is 1:
1.
3. The process for the preparation of a fiber reinforced polyphenylene sulfide / polyamide composite according to claim 1, characterized in that: In ultrasonic impregnation, the ultrasonic frequency is 20-40 kHz, the power is 500-1500W, and the temperature of the impregnation solution is 290-310℃.
4. The method for preparing fiber-reinforced polyphenylene sulfide / polyamide composite material according to claim 1, characterized in that: The compatibilizer is maleic anhydride-grafted hydrogenated styrene-butadiene-styrene block copolymer (SEBS-g-MAH).
5. The method for preparing fiber-reinforced polyphenylene sulfide / polyamide composite material according to claim 1, characterized in that: The antioxidant is pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionic acid].
6. The method for preparing fiber-reinforced polyphenylene sulfide / polyamide composite material according to claim 1, characterized in that: Before mixing polyphenylene sulfide (PPS) and polyamide 66 (PA66), vacuum dry at 100-120℃ for 4-6 hours; The extrusion temperature of a twin-screw extruder is 250-290℃.
7. A fiber-reinforced polyphenylene sulfide / polyamide composite material obtained by the preparation method of fiber-reinforced polyphenylene sulfide / polyamide composite material according to any one of claims 1-6.