Fiber-wound foam composite board as well as preparation method and application thereof

Abstract

The invention relates to the technical field of composite board preparation, in particular to a fiber winding foam composite board and a preparation method and application thereof. Uniformly winding PET polyester filaments on PET polyester foam to obtain a winding material; the PET polyester filament has a skin-core structure; and the winding material is subjected to hot pressing treatment and cooling, and the fiber winding foam composite board is obtained. The problem that the fiber wound foam composite board cannot be processed again is solved, the application range of the fiber wound foam composite board in some fields is widened, the strength of the composite board is improved, the requirements of high-requirement application scenes are met, meanwhile, different materials of all parts of the composite board are reduced, the recycling difficulty is lowered, and environmental protection is facilitated.

Description

Technical Field

[0001] The invention relates to the technical field of composite board preparation, and in particular to a fiber-wound foam composite board and a preparation method and application thereof. Background Art

[0002] In modern industrial production and life, composite materials are widely used in various fields due to their excellent performance. Composite materials can be classified into thermoplastic materials and thermosetting materials according to their processing performance. Thermosetting materials are generally difficult to recycle and reuse due to their insoluble and infusible characteristics. Thermoplastic materials have been steadily developed as matrix materials for fiber-reinforced composite materials, especially in the fields of automobiles and aerospace applications, mainly because thermoplastic materials are recyclable and can be processed quickly. They have better fracture toughness than thermosetting resins and can be easily connected using welding technology. "Yang Ying. Thermoplastic Composites - Recyclable and Fast Processing [J]. FRP, 2012 (2): 7." records that the fiber winding process is one of the main manufacturing processes for resin-based composite materials. It is a composite molding method that uses special winding equipment to impregnate continuous fibers or cloth tapes with resin glue under controlled tension and predetermined linear conditions, and then continuously, evenly and regularly winds them on a core mold or lining, and then solidifies them under a certain temperature environment to form a product of a certain shape. "Xu Jiazhong. Principles and Processes of Fiber-Wound Composite Material Forming [M]. Science Press, 2013." records that the production of composite panels usually uses multi-layer composites, with a rigid skin layer on the outermost side, which is bonded to lightweight materials such as foam or honeycomb on the inner side through an adhesive layer.

[0003] Existing fiber-wound foam composite boards mainly use thermosetting materials as the base material, such as epoxy resin, phenolic resin, etc. After curing, the physical properties of these materials will not change with temperature changes, so they are not easy to deform during use and have good stability. In addition, in order to improve the strength of the composite board, reinforcing materials such as glass fiber and carbon fiber are usually added.

[0004] Moreover, there are some problems with the existing fiber-wrapped foam composite panels. First, since thermosetting materials are used, once cured, they cannot be processed again, which limits their application in certain fields or complex shapes. This is described in Chinese patent CN101646548A, which requires the use of thermosetting resin to infuse all core and skin reinforcements to provide overall material strength. Secondly, although thermosetting resins are used, the strength of the composite panel is still limited. Reinforced fiber materials need to be added to meet some high-demand application scenarios. Chinese patent CN115703280A records the cutting and stacking of thermosetting epoxy resin fiber layers and thermoplastic resin layers, combined with hot pressing technology, to achieve composite panel manufacturing. Finally, since the materials of each part or each layer of the composite panel in the multi-layer structure are different, it is difficult to recycle and reuse, which is not conducive to environmental protection. Summary of the invention

[0005] In order to solve the above problems, the present invention provides a fiber-wound foam composite board and its preparation method and application, which solves the following problems: 1) The fiber-wound foam composite board cannot be processed again; 2) The strength of the composite board is limited and cannot meet the problem of some high-demand application scenarios; 3) The different parts of the composite board are made of different materials, which makes it difficult to recycle and reuse, which is not conducive to environmental protection. Drawing on the high degree of freedom of the winding process, the production process of thermosetting composite materials is creatively combined with thermoplastic materials to provide a fiber-wound foam composite board that can be processed and is environmentally friendly.

[0006] In order to achieve the above object, the present invention provides the following technical solutions:

[0007] The present invention provides a method for preparing a fiber-wound foam composite board, comprising the following steps:

[0008] 1) Evenly winding the PET polyester filaments on the PET polyester foam to obtain a winding material;

[0009] The PET polyester filament has a skin-core structure, the skin layer is co-PET with a melting point of 180-230° C., and the core layer is PET with a melting point of 260° C.

[0010] The mass ratio of the skin layer to the core layer is 3-5:5-7;

[0011] The fiber monofilament strength of the PET polyester filament is 4-6 cN / detx, the diameter of the PET polyester filament is 13.2-19 μm, and the monofilament initial modulus of the PET polyester filament is 30-50 cN / dtex;

[0012] The density of the PET polyester foam is 150-200 g / cm 3 , thickness is 12~17mm;

[0013] 2) The winding material obtained in step 1) is subjected to hot pressing treatment and cooling to obtain a fiber-wound foam composite board.

[0014] Preferably, in the step 1), the density of the PET polyester filaments wound on the PET polyester foam is: the weight of the PET polyester filaments per square meter is 450-850g.

[0015] Preferably, the winding conditions in step 1) include: a winding angle of 30°, a winding speed of 1 m / s, and a winding tension of 10 N.

[0016] Preferably, the conditions of the hot pressing treatment in step 2) include: temperature of 240° C., pressure of 5 MPa, and time of 2 min.

[0017] Preferably, the cooling conditions include: temperature below 45° C., pressure of 5 MPa, and time of 2 min.

[0018] Preferably, the preparation method of the PET polyester filament in step 1) comprises the following steps: melting the skin layer and the core layer separately, spinning after mixing, and drawing after cooling to obtain the PET polyester filament.

[0019] The present invention provides a fiber-wound foam composite board prepared by the preparation method described in the above technical solution.

[0020] The present invention also provides the use of the fiber-wound foam composite board described in the above technical solution in improving the peeling strength of the composite board.

[0021] The present invention also provides the use of the fiber-wound foam composite board described in the above technical solution in improving the bending modulus of the composite board.

[0022] The present invention also provides the use of the fiber-wound foam composite board described in the above technical solution in improving the bending strength of the composite board.

[0023] Beneficial effects of the present invention:

[0024] 1. Use high-strength PET polyester filaments with a two-component structure as the fiber. The two-component structure of this fiber is a skin-core structure, and the two components are polyester resins with a melting point difference of more than 30°C, and the melting point of the skin layer is lower. This design makes the fiber under hot pressing, the low-melting-point PET in the skin layer will melt and adhere to the high-melting-point PET filament fibers in the core layer, forming a high-strength fiber network, thereby improving the strength of the composite board.

[0025] 2. PET polyester foam is used as the inner layer of the composite board, and high-strength polyester filament fibers are wound on the polyester foam through a winding process, and then the composite board is obtained after hot pressing and cooling. The three-layer composite structure can improve the overall strength of the board, and because the fiber and foam are both PET polyester, which are different forms of a single compound, it is conducive to recycling and reuse, reducing environmental pollution.

[0026] 3. The surface layer of the composite board is high-strength two-component PET filament. Under the action of heat and pressure, the low-melting-point PET in the cortex will melt, and no additional adhesive components such as glue or adhesive film are required to adhere to the PET foam, forming a stable and high-strength interlayer bond. This design, which completely uses thermoplastic polymer materials, allows the composite board to soften and be pressed into a certain shape in the mold when heated to a sufficiently high temperature, making the molding faster and the design more flexible.

[0027] The comprehensive application of the above three technical means not only solves the problem that the fiber-wrapped foam composite board cannot be reprocessed, and increases its application range in certain fields, but also improves the strength of the composite board, meeting the needs of high-demand application scenarios. At the same time, it also reduces the difficulty of recycling and reuse due to the different materials of each part of the composite board, which is beneficial to environmental protection.

[0028] This approach eliminates the need for resin matrix materials, films or adhesives, providing a self-adhering or self-supporting fabric or material. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required to be used in the embodiments are briefly introduced below.

[0030] Figure 1 It is a schematic diagram of PET polyester filament winding PET polyester foam;

[0031] Figure 2 Schematic diagram of the heat resistance test of the composite board in Example 1. DETAILED DESCRIPTION

[0032] The present invention provides a method for preparing a fiber-wound foam composite board, comprising the following steps:

[0033] 1) Evenly winding the PET polyester filaments on the PET polyester foam to obtain a winding material;

[0034] The PET polyester filament has a skin-core structure, the skin layer is co-PET with a melting point of 180-230° C., and the core layer is PET with a melting point of 260° C.

[0035] The mass ratio of the skin layer to the core layer is 3-5:5-7;

[0036] The fiber monofilament strength of the PET polyester filament is 4-6 cN / detx, the diameter of the PET polyester filament is 13.2-19 μm, and the monofilament initial modulus of the PET polyester filament is 30-50 cN / dtex;

[0037] The density of the PET polyester foam is 150-200 g / cm 3 , thickness is 12~17mm;

[0038] 2) The winding material obtained in step 1) is subjected to hot pressing treatment and cooling to obtain a fiber-wound foam composite board.

[0039] The invention is to uniformly wind PET polyester filaments on PET polyester foam to obtain a winding material; the PET polyester filaments have a skin-core structure, the skin layer is co-PET with a melting point of 180-230°C, and the core layer is PET polyester with a melting point of 260°C; the mass ratio of the skin layer to the core layer is 3-5:5-7; the fiber single filament strength of the PET polyester filaments is 4-6 cN / detx, the diameter of the PET polyester filaments is 15-19 μm; the density of the PET polyester foam is 150-200 g / cm 3 , with a thickness of 12 to 17 mm. The present invention has no special restrictions on the source of the co-PET, such as TRN-3320AC purchased from Teijin. The present invention has no special restrictions on the source of the PET polyester, and conventional commercial products can be used, such as IG703A purchased from Sinopec. The present invention has no special restrictions on the source of the PET polyester foam, and conventional commercial products can be used, such as Divinycell PL purchased from DIAB, or PROCORE purchased from Yueke New Materials Co., Ltd. In the present invention, the density of the PET polyester filaments wound on the PET polyester foam is preferably: the weight of PET polyester filaments per square meter is 450 to 850 g. In the present invention, the winding conditions preferably include: a winding angle of 30°, a winding speed of 1 m / s, and a winding tension of 10N.

[0040] In the present invention, the preparation method of the PET polyester filament preferably includes the following steps: melting the skin layer and the core layer separately, spinning after mixing, and drawing after cooling to obtain the PET polyester filament. In the present invention, the skin layer and the core layer are preferably dried at 120-160°C for 4-8h before melting. In the present invention, the melting temperature of the skin layer is preferably 250-260°C, and the melting temperature of the core layer is preferably 280-290°C. In the present invention, the cooling conditions preferably include: a temperature of 15-28°C and a cooling air humidity of 70-90%.

[0041] The present invention performs hot pressing and cooling on the obtained winding material to obtain a fiber-wound foam composite board. In the present invention, the conditions for the hot pressing treatment preferably include: a temperature of 240°C, a pressure of 5MPa, and a time of 2min. In the present invention, the conditions for the cooling preferably include: a temperature below 45°C, a pressure of 5MPa, and a time of 2min.

[0042] The present invention also provides a fiber-wound foam composite board prepared by the preparation method described in the above technical solution.

[0043] The present invention also provides the use of the fiber-wound foam composite board described in the above technical solution in improving the peeling strength of the composite board.

[0044] The present invention also provides the use of the fiber-wound foam composite board described in the above technical solution in improving the bending modulus of the composite board.

[0045] The present invention also provides the use of the fiber-wound foam composite board described in the above technical solution in improving the bending strength of the composite board.

[0046] In order to further illustrate the present invention, the present invention is described in detail below in conjunction with embodiments, but they should not be construed as limiting the scope of protection of the present invention.

[0047] Example 1

[0048] A method for preparing a high-strength, reprocessable and environmentally friendly fiber-wound foam composite board, comprising the following steps:

[0049] Step 1: Prepare a high-strength PET polyester filament with a two-component structure (with a diameter of 13.3 μm and a single-filament initial modulus of 48.5 cN / dtex) as a fiber with a skin-core structure, wherein the skin layer is co-PET, which has a melting point of 230°C, and the core layer is conventional PET polyester, which has a melting point of 260°C, and the melting point difference between the two is 30°C. The weight ratio of the skin-core components is 3:7. The single-filament strength of the fiber is 6 cN / dtex. The high-strength PET polyester filament with a two-component structure is obtained by a well-known melt spinning process through drying, melt extrusion, drawing and other processes. Because the melting point of the skin layer co-PET is lower, it melts and adheres to each other during thermal processing, while the conventional PET in the core layer retains the fiber morphology.

[0050] The main steps of the melt spinning process of high-strength PET polyester filament with a two-component structure are as follows:

[0051] 1. Raw material preparation: Select two polyester chips with different melting points as raw materials, and then dry them: In order to avoid the adverse effects of moisture on polyester chips during the spinning process, the polyester chips need to be fully dried first, usually at 120°C for 8 hours.

[0052] 2. Chip melt extrusion: Each polyester chip enters an independent melt extrusion system and melts into a melt under its own temperature conditions. The temperature of each melting system is precisely controlled to ensure that the two melts reach an ideal flow state before entering the spinning assembly. Usually, the melt extrusion temperature of co-PET chips is about 260°C, and the melt extrusion temperature of PET polyester chips is 290°C.

[0053] 3. The melt passes through a precision metering pump and distributor, and the two components are delivered to the same spinning assembly in a predetermined ratio and manner.

[0054] 4. Spinning: The melt is squeezed out from the small holes of the spinneret to form long and thin bicomponent fibers. The fibers are rapidly cooled and solidified during the pulling process to form a stable fiber shape. The cooling temperature is generally 15°C, and the cooling air humidity is about 80%.

[0055] 5. Drawing and Winding: The fibers are drawn through a series of guide rollers to increase the length of the fibers, reduce the diameter, and increase their strength and modulus. The drawn fibers are collected and wound into a cylinder or disc for subsequent processing.

[0056] Step 2: Prepare PET polyester foam as foam with a density of 150g / cm 3 , thickness is 12mm.

[0057] Step three: Wind the two-component high-strength PET polyester filament on the polyester foam through a winding process, fix the PET polyester foam on a rotating platform, and then evenly wind the two-component high-strength PET polyester filament on the foam surface in a spiral manner. The winding density is 450g per square meter of filament weight. The high-strength PET polyester filament or PET polyester foam is not heated during the winding process. The winding angle of the high-strength PET polyester filament is 30°, the winding speed is 1m / s, and the winding tension of the high-strength PET polyester filament is 10N.

[0058] Step 4: Hot press the wound composite material and place the composite material in a flat press with a heating zone and a cooling zone. The set temperature of the heating zone is 240°C, the pressure is 5MPa, and the time is 2min. The set temperature of the cooling zone is 35°C, the pressure is 5MPa, and the time is 2min. The final high-strength, reprocessable and environmentally friendly fiber-wound foam composite board is obtained.

[0059] Polyester filaments shrink when heated. Thanks to the winding method, the polyester filaments are fastened to the foam surface after heating, and the fiber layer and polyester foam are more firmly bonded together with the applied external pressure. Through the above steps, a high-strength, reprocessable and environmentally friendly fiber-wound foam composite board was successfully prepared.

[0060] After obtaining the composite board, the inventors tested the peel strength between the skin formed by the polyester filaments and the polyester foam by using the GBT 1457-2005 sandwich structure roller peel strength test method to examine the interface bonding strength.

[0061] The flexural strength and flexural modulus of composite panels are tested using the GB / T 1456-2021 sandwich structure flexural performance test method.

[0062] In order to evaluate the heat resistance of the composite board, a test on the sag of the composite board after heat treatment was also conducted. The specific test method is: cut a rectangular spline with a size of 230*50mm, fix one end on the clamp, and extend the other end 200mm out of the clamp. The test spline and the clamp are placed in a 100℃ hot air oven for 24 hours, then taken out and cooled naturally. Measure the distance L1 between the top of the extended spline and the plane where the bottom of the clamp is located, measure the height L0 of the clamp, and the deformation of the spline after heating L=L0-L1. The clamping diagram is as follows Figure 2 As shown, 5 specimens were tested for each embodiment, and the test data were averaged.

[0063] Example 2

[0064] A method for preparing a high-strength, reprocessable and environmentally friendly fiber-wound foam composite board, comprising the following steps:

[0065] Step 1: Prepare a high-strength PET polyester filament (diameter of 14.2 μm, the initial modulus of the single filament of the PET polyester filament is 38.8 cN / dtex) with a two-component structure as a fiber, having a skin-core structure, wherein the skin layer is co-PET, whose melting point is 180°C, and the core layer is conventional PET polyester, whose melting point is 260°C. The weight ratio of the skin-core components is 3:7. The single filament strength of the fiber is 4 cN / dtex. The preparation method of the high-strength PET polyester filament with a two-component structure is the same as that in Example 1.

[0066] Step 2: Prepare PET polyester foam as foam with a density of 150g / cm 3 , thickness is 12mm.

[0067] Step three: Wind the two-component high-strength PET polyester filament on the polyester foam through a winding process, fix the PET polyester foam on a rotating platform, and then evenly wind the two-component high-strength PET polyester filament on the foam surface in a spiral manner. The winding density is 450g per square meter of filament weight. The high-strength PET polyester filament or PET polyester foam is not heated during the winding process. The winding angle of the high-strength PET polyester filament is 30°, the winding speed is 1m / s, and the winding tension of the high-strength PET polyester filament is 10N.

[0068] Step 4: Hot press the wound composite material and place the composite material in a flat press with a heating zone and a cooling zone. The set temperature of the heating zone is 240°C, the pressure is 5MPa, and the time is 2min. The set temperature of the cooling zone is 35°C, the pressure is 5MPa, and the time is 2min. The final high-strength, reprocessable and environmentally friendly fiber-wound foam composite board is obtained.

[0069] The performance was tested in the same manner as in Example 1.

[0070] Example 3

[0071] A method for preparing a high-strength, reprocessable and environmentally friendly fiber-wound foam composite board, comprising the following steps:

[0072] Step 1: Prepare a high-strength PET polyester filament (diameter of 16.1 μm, the initial modulus of the single filament of the PET polyester filament is 42.4 cN / dtex) with a bicomponent structure as a fiber having a skin-core structure, wherein the skin layer is co-PET, whose melting point is 230°C, and the core layer is conventional PET polyester, whose melting point is 260°C. The weight ratio of the skin-core components is 3:7, and the single filament strength of the fiber is 6 cN / dtex. The preparation method of the high-strength PET polyester filament with a bicomponent structure is the same as that in Example 1.

[0073] Step 2: Prepare PET polyester foam as foam with a density of 200g / cm 3 , thickness is 17mm.

[0074] Step three: Wind the two-component high-strength PET polyester filament on the polyester foam through a winding process, fix the PET polyester foam on a rotating platform, and then evenly wind the two-component high-strength PET polyester filament on the foam surface in a spiral manner. The winding density is 850g per square meter of filament weight. The high-strength PET polyester filament or PET polyester foam is not heated during the winding process. The winding angle of the high-strength PET polyester filament is 30°, the winding speed is 1m / s, and the winding tension of the high-strength PET polyester filament is 10N.

[0075] Step 4: Hot press the wound composite material and place the composite material into a flat press with a heating zone and a cooling zone. The set temperature of the heating zone is 240°C, the pressure is 5MPa, and the time is 2min. The set temperature of the cooling zone is below 45°C, the pressure is 5MPa, and the time is 2min. The final high-strength, reprocessable and environmentally friendly fiber-wound foam composite board is obtained.

[0076] The performance was tested in the same manner as in Example 1.

[0077] Example 4

[0078] A method for preparing a high-strength, reprocessable and environmentally friendly fiber-wound foam composite board, comprising the following steps: except for selecting a skin-core component weight ratio of 5:5, the other implementation conditions are the same as those of Example 3.

[0079] Comparative Example 1

[0080] A method for preparing a fiber-wound foam composite board, comprising the following steps:

[0081] Step 1: Prepare a single-component PET polyester filament (diameter of 18.8 μm, the PET polyester filament has a single-filament initial modulus of 46.8 cN / dtex) as the fiber, and select a conventional PET polyester filament with a melting point of 260° C. The fiber single-filament strength is 6 cN / dtex.

[0082] Step 2: Prepare PET polyester foam as foam with a density of 150g / cm 3 , thickness is 12mm.

[0083] Step three: wind the single-component PET polyester filament on the polyester foam through a winding process, fix the PET polyester foam on a rotating platform, and then evenly wind the single-component PET polyester filament on the foam surface in a spiral manner. The winding density is 450g per square meter of filament weight. The single-component PET polyester filament or PET polyester foam is not heated during the winding process. The winding angle of the single-component PET polyester filament is 30°, the winding speed is 1m / s, and the winding tension of the single-component PET polyester filament is 10N.

[0084] Step 4: Hot press the wound composite material and place it in a flat press with a heating zone and a cooling zone. The set temperature of the heating zone is 240°C, the pressure is 5MPa, and the time is 2min. The set temperature of the cooling zone is 35°C, the pressure is 5MPa, and the time is 2min to obtain the final composite sheet.

[0085] The performance was tested in the same manner as in Example 1.

[0086] Table 1 Test results of composite boards prepared in Examples 1 to 4 and Comparative Example 1

[0087]

[0088]

[0089] From the data of Examples 1 and 2, it can be seen that when the polyester filament skin layer has a lower melting point, the peel strength is higher. Because under the same hot pressing process, the lower melting point can make the skin layer melt more fully, and after melting, a certain flow is generated, and the bonding effect with the foam is better. As explained in Example 2, considering the use scenario of the material's heat resistance, the skin layer co-PET with a melting point below 180°C was not selected.

[0090] At the same time, it can be seen that when the cortex is selected with a lower melting point, the corresponding single filament strength decreases, which is related to the difference in the molecular chains of the filaments. The surface strength of the sandwich structure will significantly affect the bending strength of the structure. The decrease in single filament strength leads to a decrease in bending strength, indicating that the strength of the cortex formed by the polyester filaments after winding in Example 2 is lower than that in Example 1.

[0091] From the data of Examples 1 and 3, the bending performance of Example 3 is significantly improved due to the selection of PET foam with higher strength and PET polyester filament skin with higher gram weight. It can be used as a substrate for load-bearing components and applied to vehicles, simple houses, etc.

[0092] Comparing Example 3 with Example 4, Example 4 has better peel strength because of more low melting point polyester resin, but the market price of low melting point polyester is generally higher, so a high ratio is not conducive to the overall cost control of the material. In actual implementation, the corresponding parameters can be adjusted according to the specific usage scenario to meet the best performance requirements.

[0093] The peel strength of Comparative Example 1 was extremely poor because the polyester fiber with a conventional melting point could not be bonded to the polyester foam in the absence of a bonding component. The corresponding bending properties were not tested.

[0094] Although the above embodiment describes the present invention in detail, it is only a part of the embodiments of the present invention, not all of the embodiments. People can also obtain other embodiments based on this embodiment without creativity, and these embodiments all fall within the protection scope of the present invention.

Claims

1. A method for preparing a fiber-wound foam composite board, characterized in that: The following steps are involved: 1) Evenly winding the PET polyester filaments on the PET polyester foam to obtain a winding material; The PET polyester filament has a skin-core structure, the skin layer is co-PET with a melting point of 180-230° C., and the core layer is PET with a melting point of 260° C. The mass ratio of the skin layer to the core layer is 3-5:5-7; The fiber single fiber strength of the PET polyester filament is 4-6 cN / dtex, the diameter of the PET polyester filament is 13.2-19 μm, and the single fiber initial modulus of the PET polyester filament is 30-50 cN / dtex; The density of the PET polyester foam is 150-200 g / cm 3 , thickness is 12~17mm; 2) The winding material obtained in step 1) is subjected to hot pressing treatment and cooling to obtain a fiber-wound foam composite board.

2. The preparation method according to claim 1, characterized in that: In the step 1), the density of the PET polyester filaments wound on the PET polyester foam is: the weight of the PET polyester filaments per square meter is 450-850g.

3. The preparation method according to claim 1, characterized in that: The winding conditions in step 1) include: a winding angle of 30°, a winding speed of 1 m / s, and a winding tension of 10 N.

4. The preparation method according to claim 1, characterized in that: The conditions of the hot pressing treatment in step 2) include: temperature of 240° C., pressure of 5 MPa, and time of 2 min.

5. The preparation method according to claim 1, characterized in that: The cooling conditions in step 2) include: temperature below 45° C., pressure of 5 MPa, and time of 2 min.

6. The preparation method according to claim 1, characterized in that: The preparation method of the PET polyester filament in step 1) comprises the following steps: melting the skin layer and the core layer separately, spinning after mixing, and drawing after cooling to obtain the PET polyester filament.

7. A fiber-wound foam composite board prepared by the preparation method according to any one of claims 1 to 6.

8. Use of the fiber-wound foam composite board material according to claim 7 in improving the peel strength of the composite board material.

9. Use of the fiber-wound foam composite board material according to claim 7 in improving the bending modulus of the composite board material.

10. Use of the fiber-wound foam composite board material according to claim 7 in improving the bending strength of the composite board material.

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