A thermoplastic composite nut and its preparation method and application

Abstract

The present disclosure relates to a thermoplastic composite connecting component, and in particular to a thermoplastic composite nut and its preparation method and application. The thermoplastic composite nut is composed of three annular laminates from the inside to the outside, namely an inner rigid ring, an intermediate transition reinforcement support ring, and a surface mixed fiber reinforced structural ring; it includes the steps of laminated primary plastic molding and overall secondary plastic molding, wherein the inner surface of the inner rigid ring is made of two-dimensionally wound high modulus carbon fiber and polyethylene plastic molding; the intermediate transition reinforcement support ring is made of carbon fiber reinforcement along the axial direction of the nut and propylene resin plastic molding; the surface mixed fiber reinforced structural ring is made of mixed carbon fiber and high tenacity fiber and thermoplastic polyester resin plastic molding; the overall secondary plastic molding arranges the three annular laminates to be made according to the internal and external structures and then plastic molds them. It solves the problem that thermosetting resin nuts in the prior art are not easy to recycle and cannot be prepared into nuts with composite structures, which affects the mechanical properties of the nuts.

Description

Technical Field

[0001] The present disclosure relates to a thermoplastic composite connecting component, and in particular to a thermoplastic composite nut and a preparation method and application thereof. Background Art

[0002] The statements herein merely provide background information related to the present disclosure and may not necessarily constitute prior art.

[0003] Nuts and bolts are common fastening devices. Nuts and bolts in the prior art are mostly made of metal materials. However, metal nuts and bolts are relatively rigid and are prone to loosening. On the other hand, metal nuts and bolts are prone to rust and are difficult to disassemble if they are inactive for a long time.

[0004] To solve this problem, the prior art has proposed a method of preparing nuts using thermosetting plastics. The resin has a certain fluidity relative to the metal, and the resin is easier to combine with the metal. Therefore, the tightness with the metal is better and it is not easy to loosen. However, the inventors found that with the continuous expansion of the application fields of thermosetting composite materials, many problems of thermosetting composite material components have gradually emerged. Since the matrix resin is an infusible three-dimensional network structure, the secondary use and recycling of composite material components based on this has become a huge technical problem in the application of this composite material. Summary of the invention

[0005] The invention aims to solve the problem that thermosetting resin nuts in the prior art are difficult to recycle and reuse, and it is impossible to prepare nuts with composite structures, which affects the mechanical properties of the nuts.

[0006] In one or some embodiments of the present disclosure, there is provided a thermoplastic composite nut, which includes, from inside to outside, a surface thread layer, an internal rigid ring, an intermediate transition reinforcement support ring, and a hybrid fiber reinforcement ring;

[0007] The surface thread layer is a carbon fiber composite thermoplastic resin layer, and the inner surface is a thread structure;

[0008] The main body of the internal rigid ring is high modulus carbon fiber along the axial direction of the nut;

[0009] The main body of the intermediate transition reinforcement support ring is high-strength carbon fiber along the axial direction of the nut;

[0010] The hybrid fiber reinforced ring is composed of thermoplastic resin and hybrid fibers.

[0011] In one or some embodiments of the present disclosure, a method for preparing a thermoplastic composite nut is provided, wherein the thermoplastic composite nut is composited from the inside to the outside by three annular laminates, namely an inner rigid ring, an intermediate transition reinforcement support ring, and a surface mixed fiber reinforcement structure ring;

[0012] It includes the steps of lamination primary plasticizing and molding and overall secondary plasticizing and molding.

[0013] The stacking is plasticized once, i.e., three annular stacks are plasticized by resin, carbon fiber or mixed fiber. Specifically, the inner surface of the inner rigid ring is plasticized by two-dimensionally wound high modulus carbon fiber and polyethylene; the body of the inner rigid ring is reinforced by high modulus carbon fiber arranged along the axial direction.

[0014] The intermediate transition reinforcement support ring is made of carbon fiber reinforcement along the axial direction of the nut and propylene resin plastic molding;

[0015] The surface mixed fiber reinforced structural ring is made of mixed carbon fiber and high-tenacity fiber and thermoplastic polyester resin plastic molding;

[0016] The three annular laminates to be manufactured by the overall secondary plastic molding are arranged according to the internal and external structures and then plastic molded.

[0017] In one or some embodiments of the present disclosure, a thermoplastic composite nut prepared by the above-mentioned preparation method of the thermoplastic composite nut is provided.

[0018] In one or some embodiments of the present disclosure, there is provided a fastening device, comprising the above-mentioned thermoplastic composite nut and bolt, wherein the thread of the bolt corresponds to the thread of the surface thread layer.

[0019] One or some of the above technical solutions have the following advantages or beneficial effects:

[0020] 1) The present invention adopts thermoplastic material and carbon fiber to prepare composite nuts, which avoids the problem that thermosetting composite materials are difficult to recycle. In addition, carbon fiber is added to the thermoplastic material for compounding, and the mechanical properties of the composite nut are greatly improved.

[0021] 2) The present disclosure provides a method for preparing a thermoplastic composite nut, the structure of which includes the following parts: an internal rigid ring, an intermediate transition reinforcement support ring, and a surface mixed fiber reinforced structural ring. The inner surface of the internal rigid ring is made of circumferentially wound carbon fiber reinforced thermoplastic resin, and its inner surface can be processed by secondary thread machining. The main body of the internal rigid ring is arranged with high modulus carbon fibers along the axial direction of the nut to provide rigid support for the nut as a whole; the intermediate transition reinforcement support ring is arranged with high-strength carbon fibers along the axial direction of the nut, and composite processing is performed with thermoplastic resin as the matrix; the surface mixed fiber reinforced structural ring is mixed with high-strength carbon fibers and high-tenacity fibers for hybrid reinforcement, and composite processing is performed with thermoplastic resin as the matrix. The composite nut prepared by compositely preparing the three layers of different fibers in different arrangements and composited with a thermoplastic resin matrix has a variety of mechanical and mechanical properties such as light weight, high rigidity, high strength and friction resistance, and can easily replace metal parts to become a key application product of composite material structural connection components. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The accompanying drawings constituting a part of the present disclosure are used to provide a further understanding of the present disclosure. The illustrative embodiments of the present disclosure and their descriptions are used to explain the present disclosure and do not constitute an improper limitation on the present disclosure.

[0023] Figure 1 It is a structural cross-sectional view of the thermoplastic composite nut described in Examples 1-4.

[0024] Among them, 1. internal rigid ring; 2. middle transition reinforcement support ring; 3. surface mixed fiber reinforced structural ring; 4. surface threaded layer. DETAILED DESCRIPTION

[0025] The technical solutions in the embodiments of the present disclosure are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present disclosure, not all of them. Based on the embodiments of the present disclosure, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present disclosure.

[0026] The invention aims to solve the problem that thermosetting resin nuts in the prior art are difficult to recycle and reuse, and it is impossible to prepare nuts with composite structures, which affects the mechanical properties of the nuts.

[0027] In one or some embodiments of the present disclosure, there is provided a thermoplastic composite nut, which includes, from inside to outside, a surface thread layer, an internal rigid ring, an intermediate transition reinforcement support ring, and a hybrid fiber reinforcement ring;

[0028] The surface thread layer is a carbon fiber composite thermoplastic resin layer, and the inner surface is a thread structure;

[0029] The main body of the internal rigid ring is high modulus carbon fiber along the axial direction of the nut;

[0030] The main body of the intermediate transition reinforcement support ring is high-strength carbon fiber along the axial direction of the nut;

[0031] The hybrid fiber reinforced ring is composed of thermoplastic resin and hybrid fibers.

[0032] Preferably, the inner surface of the inner rigid ring is circumferentially wound with carbon fibers, and the fibers are wound in a two-dimensional winding arrangement.

[0033] Preferably, the two-dimensional winding arrangement includes circumferential winding, spiral winding, and longitudinal winding.

[0034] Preferably, the winding angle of the circumferential winding is controlled within the range of 85-90°; the winding angle of the helical winding is controlled within the range of 45-70°; and the winding angle of the longitudinal winding does not exceed 25°.

[0035] Preferably, the high modulus carbon fiber includes M40, M40J, M55, M55J, M60, and M60J.

[0036] Preferably, the high-strength carbon fiber is any one of T300, T700, T800 and T1000 carbon fiber;

[0037] Preferably, the hybrid fibers include high-strength carbon fibers and high-tenacity fibers, wherein the high-strength carbon fibers include T300, T700, T800, and T1000 carbon fibers, and the high-tenacity fibers include aramid fibers, UHMWPE fibers, and PBO fibers.

[0038] Preferably, the thermoplastic resin includes polyethylene, polypropylene, polycarbonate, thermoplastic polyester, polyphenylene sulfide, polyetheretherketone, polyetherketone, polyamide, and polyimide.

[0039] In one or some embodiments of the present disclosure, a method for preparing a thermoplastic composite nut is provided, wherein the thermoplastic composite nut is composited from the inside to the outside by three annular laminates, namely an inner rigid ring, an intermediate transition reinforcement support ring, and a surface mixed fiber reinforcement structure ring;

[0040] It includes the steps of lamination primary plasticizing and molding and overall secondary plasticizing and molding.

[0041] The stacking is plasticized once, i.e., three annular stacks are plasticized by resin, carbon fiber or mixed fiber. Specifically, the inner surface of the inner rigid ring is plasticized by two-dimensionally wound high modulus carbon fiber and polyethylene; the body of the inner rigid ring is reinforced by high modulus carbon fiber arranged along the axial direction.

[0042] The intermediate transition reinforcement support ring is made of carbon fiber reinforcement along the axial direction of the nut and propylene resin plastic molding;

[0043] The surface mixed fiber reinforced structural ring is made of mixed carbon fiber and high-tenacity fiber and thermoplastic polyester resin plastic molding;

[0044] The three annular laminates to be manufactured by the overall secondary plastic molding are arranged according to the internal and external structures and then plastic molded.

[0045] Preferably, the inner surface of the inner rigid ring is circumferentially wound with carbon fiber, and any one of M40, M40J, M55, M55J, M60, and M60J can be selected.

[0046] Alternatively, the two-dimensional winding arrangement includes circumferential winding, spiral winding, and longitudinal winding, wherein the winding angle of the circumferential winding is controlled within the range of 85-90°, the winding angle of the spiral winding is controlled within the range of 45-70°, and the winding angle of the longitudinal winding does not exceed 25°.

[0047] Preferably, the entire internal rigid ring is based on thermoplastic resin, and the matrix content of the entire rigid ring is controlled within the range of 40-60%, which can be flexibly adjusted according to design requirements.

[0048] Preferably, the thermoplastic resin matrix of the inner rigid ring includes one or more of polyethylene, polypropylene, polycarbonate, thermoplastic polyester, polyphenylene sulfide, polyetheretherketone, polyetherketone, polyamide, and polyimide.

[0049] Preferably, the intermediate transition reinforcement support ring is made of high-strength carbon fibers arranged along the axial direction of the nut and composited with thermoplastic resin as the matrix;

[0050] Preferably, the high-strength carbon fiber includes T300, T700, T800, and T1000 carbon fiber;

[0051] Or, the thermoplastic resin matrix of the intermediate transition reinforcement support ring includes one or more of polyethylene, polypropylene, polycarbonate, thermoplastic polyester, polyphenylene sulfide, polyetheretherketone, polyetherketone, polyamide, and polyimide;

[0052] Alternatively, the matrix content of the entire intermediate transition reinforcement support ring is controlled within the range of 40-60%, and can be flexibly adjusted according to design requirements.

[0053] Preferably, the surface hybrid fiber reinforced structural ring is hybrid reinforced with high-strength carbon fiber and high-tenacity fiber, and composite processed with thermoplastic resin as the matrix.

[0054] Preferably, the high-strength carbon fiber includes T300, T700, T800, and T1000 carbon fiber, and the high-tenacity fiber includes aramid fiber, UHMWPE fiber, and PBO fiber. The mixing ratio of the two fibers can be flexibly adjusted according to design requirements.

[0055] Or, the thermoplastic resin matrix of the surface mixed fiber reinforced structural ring includes one or more of polyethylene, polypropylene, polycarbonate, thermoplastic polyester, polyphenylene sulfide, polyetheretherketone, polyetherketone, polyamide, and polyimide,

[0056] Or, the resin matrix content is controlled within the range of 40-60%.

[0057] Preferably, the specific steps of overall secondary plasticizing and molding include:

[0058] Arrange the three annular layers according to the internal and external structures and place them in a nut mold with a certain cavity for secondary plasticization of the thread. Heat the nut according to the hot melt plasticization characteristics of the resin matrix. When the temperature reaches the hot melt temperature of the resin of the nut, pressurize it. After the mold cools down, take out the nut sample.

[0059] Preferably, the plasticizing temperature is controlled within the range of 180-290° C., the pressurizing pressure is controlled within the range of 2-8 MPa, and the time of secondary plasticizing thread processing is controlled within the range of 2-5 hours.

[0060] In one or some embodiments of the present disclosure, a thermoplastic composite nut prepared by the above-mentioned preparation method of the thermoplastic composite nut is provided.

[0061] In one or some embodiments of the present disclosure, there is provided a fastening device, comprising the above-mentioned thermoplastic composite nut and bolt, wherein the thread of the bolt corresponds to the thread of the surface thread layer.

[0062] Preferably, the bolt is a metal bolt.

[0063] Example 1

[0064] like Figure 1 As shown, this embodiment provides a method for preparing a thermoplastic composite nut, wherein the thermoplastic composite nut includes an internal rigid ring, an intermediate transition reinforcement support ring, and a surface mixed fiber reinforcement structure ring.

[0065] The inner surface of the internal rigid ring is made of two-dimensionally wound M40 high modulus carbon fiber reinforced with 40% polyethylene, and the winding method can be a circumferential winding method with a winding angle controlled at 85°; the main body of the internal rigid ring is made of axially arranged M60J high modulus carbon fiber reinforced with 60% polyethylene resin.

[0066] The intermediate transition reinforcement support ring is made of polypropylene resin with a T300 carbon fiber reinforcement content of 45% along the axial direction of the nut.

[0067] The surface hybrid fiber reinforced structural ring is composed of T300 carbon fiber and K49 aramid fiber in a mixed ratio of 1:1, and the resin matrix of the surface hybrid fiber reinforced structural ring is thermoplastic polyester resin with a content of 55%.

[0068] After the above-mentioned laminated structure is plasticized and formed, it is placed in a nut mold with a certain cavity for secondary plasticization processing of the thread, and the temperature is increased according to the hot melt plasticization characteristics of the resin matrix. When the temperature reaches the hot melt temperature of the resin of the nut, it is pressurized, wherein the plasticization temperature is controlled within the range of 220°C, the pressurization pressure is controlled within the range of 3MPa, and the time of the secondary plasticization thread processing is controlled within the range of 3 hours. After the mold is cooled, the nut sample is taken out.

[0069] Example 2

[0070] like Figure 1 As shown, this embodiment provides a method for preparing a thermoplastic composite nut, wherein the thermoplastic composite nut includes an internal rigid ring, an intermediate transition reinforcement support ring, and a surface mixed fiber reinforcement structure ring.

[0071] The inner surface of the internal rigid ring is made of two-dimensionally wound M40J high modulus carbon fiber reinforced with a polyimide resin content of 50%, and the winding method can be a spiral winding method with a winding angle controlled at 45°; the main body of the internal rigid ring is made of axially arranged M60 high modulus carbon fiber reinforced with a polycarbonate resin content of 54%.

[0072] The intermediate transition reinforcement support ring is made of polyamide resin with a T1000 carbon fiber reinforcement content of 50% along the axial direction of the nut.

[0073] The surface hybrid fiber reinforced structural ring is composed of T700 carbon fiber and UHMWPE fiber with a mixing ratio of 3:1, and the resin matrix of the surface hybrid fiber reinforced structural ring is polyphenylene sulfide resin with a content of 45%.

[0074] After the above-mentioned laminated structure is plasticized and formed, it is placed in a nut mold with a certain cavity for secondary plasticization processing of the thread, and the temperature is increased according to the hot melt plasticization characteristics of the resin matrix. When the temperature reaches the hot melt temperature of the resin of the nut, it is pressurized, wherein the plasticization temperature is controlled within the range of 280°C, the pressurization pressure is controlled within the range of 4MPa, and the time of the secondary plasticization thread processing is controlled within the range of 4 hours. After the mold is cooled, the nut sample is taken out.

[0075] Example 3

[0076] like Figure 1As shown, this embodiment provides a method for preparing a thermoplastic composite nut, wherein the thermoplastic composite nut includes an internal rigid ring, an intermediate transition reinforcement support ring, and a surface mixed fiber reinforcement structure ring.

[0077] The inner surface of the internal rigid ring is made of two-dimensionally wound M55 high modulus carbon fiber reinforced with a 52% polyetheretherketone resin, and the winding method can be a longitudinal winding method with a winding angle not exceeding 25°; the main body of the internal rigid ring is made of axially arranged M55 high modulus carbon fiber reinforced with a 55% polyphenylene sulfide resin.

[0078] The intermediate transition reinforcement support ring is made of polyetherketone resin with a T800 carbon fiber reinforcement content of 48% along the axial direction of the nut.

[0079] The surface hybrid fiber reinforced structural ring is composed of T800 carbon fiber and PBO fiber with a mixing ratio of 4:1, and the resin matrix of the surface hybrid fiber reinforced structural ring is a polyimide resin with a content of 60%.

[0080] After the above-mentioned laminated structure is plasticized and formed, it is placed in a nut mold with a certain cavity for secondary plasticization processing of the thread, and the temperature is increased according to the hot melt plasticization characteristics of the resin matrix. When the temperature reaches the hot melt temperature of the resin of the nut, it is pressurized, wherein the plasticization temperature is controlled within the range of 290°C, the pressurization pressure is controlled within the range of 8MPa, and the time of the secondary plasticization thread processing is controlled within the range of 5 hours. After the mold is cooled, the nut sample is taken out.

[0081] Example 4

[0082] like Figure 1 As shown, this embodiment provides a method for preparing a thermoplastic composite nut, wherein the thermoplastic composite nut includes an internal rigid ring, an intermediate transition reinforcement support ring, and a surface mixed fiber reinforcement structure ring.

[0083] The inner surface of the internal rigid ring is made of two-dimensionally wound M55J high modulus carbon fiber reinforced with a 60% polyamide content, and the winding method can be a longitudinal winding method with a winding angle not exceeding 20°; the main body of the internal rigid ring is made of axially arranged M60 high modulus carbon fiber reinforced with a 50% polyimide resin.

[0084] The intermediate transition reinforcement support ring is made of thermoplastic polyester resin with a T1000 carbon fiber reinforcement content of 50% along the axial direction of the nut.

[0085] The surface hybrid fiber reinforced structural ring is composed of T1000 carbon fiber and UHMWPE fiber with a mixing ratio of 5:1, and the resin matrix of the surface hybrid fiber reinforced structural ring is a polyimide resin with a content of 55%.

[0086] After the above-mentioned laminated structure is plasticized and formed, it is placed in a nut mold with a certain cavity for secondary plasticization processing of the thread, and the temperature is increased according to the hot melt plasticization characteristics of the resin matrix. When the temperature reaches the hot melt temperature of the resin of the nut, it is pressurized, wherein the plasticization temperature is controlled within the range of 270°C, the pressurization pressure is controlled within the range of 6MPa, and the time of the secondary plasticization thread processing is controlled within the range of 4 hours. After the mold is cooled, the nut sample is taken out.

[0087] Comparative Example 1

[0088] This embodiment provides a method for preparing a thermoplastic composite nut, which is different from Embodiment 1 in that the composite nut is entirely made of a surface mixed fiber reinforced structural ring.

[0089] Comparative Example 2

[0090] This embodiment provides a method for preparing a thermoplastic composite nut, which is different from Embodiment 1 in that the inner surface of the inner rigid ring is made by plasticizing and molding three-dimensionally wound high modulus carbon fibers and polyethylene.

[0091] Comparative Example 3

[0092] This embodiment provides a method for preparing a thermoplastic composite nut, which differs from Embodiment 1 in that the inner surface of the internal rigid ring is made by plasticizing and molding high modulus carbon fiber and polyethylene wound in an annular direction, and the winding angle of the annular winding is 75 degrees.

[0093] The thermoplastic composite nuts prepared in Examples 1-4 and Comparative Examples 1-3 were tested for mechanical properties. It was found that although the thermoplastic composite nuts described in Comparative Example 1 were all made of surface mixed fiber reinforced structural rings with the highest strength, the actual mechanical properties were worse. Comparative Example 2 used three-dimensional winding. The inventors found that in actual applications, the composite structure of the nut was easy to separate and fall off. Obviously, two-dimensional winding helps the two-phase interface to be tightly combined. The composite nut described in Comparative Example 3 has a large winding angle and the two-dimensional structure is easy to loosen. In actual applications, it cannot meet the mechanical performance requirements.

[0094] From the comparison of the above mechanical properties, it can be seen that the nuts are all made of the surface mixed fiber reinforced structural ring with the strongest rigidity, but the mechanical properties are worse than those of the three-layer annular laminate. It can be seen that the matching relationship of the three-layer annular laminate improves the mechanical properties of the nut.

[0095] From comparative examples 2 and 3, it can be seen that the two-dimensional winding is adopted and the specific angle is limited, which is beneficial to improving the mechanical properties of the composite nut.

[0096] The above disclosure is only the preferred embodiment of the present disclosure, which certainly cannot be used to limit the scope of rights of the present disclosure. Therefore, equivalent changes made according to the scope of the patent application of the present disclosure are still within the scope covered by the present disclosure.

Claims

1. A thermoplastic composite nut, characterized in that: From the inside to the outside, it includes a surface thread layer, an internal rigid ring, an intermediate transition reinforcement support ring and a mixed fiber reinforcement ring; The surface thread layer is a carbon fiber composite thermoplastic resin layer, and the inner surface is a thread structure; The main body of the internal rigid ring is high modulus carbon fiber along the axial direction of the nut; The main body of the intermediate transition reinforcement support ring is high-strength carbon fiber along the axial direction of the nut; The hybrid fiber reinforced ring is composed of thermoplastic resin and hybrid fibers; The inner surface of the inner rigid ring is circumferentially wound with carbon fibers, the fibers being wound in a two-dimensional winding arrangement; Two-dimensional winding arrangements include circumferential winding, spiral winding, and longitudinal winding; The winding angle of the circumferential winding is controlled within the range of 85-90°; the winding angle of the helical winding is controlled within the range of 45-70°; and the winding angle of the longitudinal winding does not exceed 25°; The high modulus carbon fiber includes M40, M40J, M55, M55J, M60, and M60J; The high-strength carbon fiber adopts any one of T300, T700, T800 and T1000 carbon fiber; The hybrid fibers include high-strength carbon fibers and high-tenacity fibers, wherein the high-strength carbon fibers include T300, T700, T800, and T1000 carbon fibers, and the high-tenacity fibers include aramid fibers, UHMWPE fibers, and PBO fibers; Thermoplastic resins include polyethylene, polypropylene, polycarbonate, thermoplastic polyester, polyphenylene sulfide, polyetheretherketone, polyetherketone, polyamide, and polyimide.

2. A fastening device, characterized in that: The thermoplastic composite nut and bolt according to claim 1, wherein the thread of the bolt corresponds to the thread of the surface thread layer.

3. A fastening device, characterized in that: The invention comprises the thermoplastic composite nut and bolt as claimed in claim 1, wherein the bolt is a metal bolt.

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