Polyester multi-component lightweight filament spun-bonded needle-punched non-woven fabric

Abstract

The invention relates to a polyester multi-component light-weight filament spun-bonded needle-punched non-woven fabric, and belongs to the technical field of non-woven fabrics, the non-woven fabric is formed by needling and shaping a plurality of layers of single nets after cross lapping, the surface density gram weight range is 1000-4000 g / m, and the density is 0.6 g / cm or below; the single net is a multi-component composite fiber net, and the fiber structure is one or a combination of two of a skin-core type, a stripping type or a parallel type; the fiber material is composed of PET and various COPET, the melting point of the PET component ranges from 220 DEG C to 260 DEG C, and the melting point of the COPET component ranges from 150 DEG C to 215 DEG C. The density of the polyester multi-component light-weight filament spun-bonded needle-punched non-woven fabric can be controlled to be 0.6 g / cm < 3 > or below, and compared with a traditional non-metallic material for an automobile, the weight of a part with the same size can be reduced by 20-30%; the weight can be reduced by 2-3 kilograms according to the fact that each trolley uses 10 kilograms of traditional materials, the accumulative effect of multiple applications of the whole trolley is remarkable, the power-to-weight ratio is optimized, and the energy consumption is reduced.

Description

Technical Field

[0001] This invention relates to the field of nonwoven fabric technology, specifically to a polyester multi-component lightweight long-fiber spunbond needle-punched nonwoven fabric, which is particularly suitable for applications with high requirements for lightweighting and recyclability, such as automotive interiors and molded parts. Background Technology

[0002] With the rapid development of the automotive industry, lightweighting has become one of the important ways to save energy and reduce emissions. Traditional automotive non-metallic materials are mostly produced through injection molding or compression molding, using materials such as PP, ABS, and glass fiber reinforced composites, with densities generally exceeding 0.9 g / cm³. Although adding glass fiber can improve the strength and impact resistance of the materials, these materials are difficult to recycle and reuse after the car is scrapped or parts are replaced, causing environmental pollution and resource waste.

[0003] While carbon fiber composites have significant advantages in terms of lightweighting and have been applied in fields such as high-end sports cars, they are more difficult to recycle and reuse. Even when crushed into short fibers, they can only be used as fillers for downgraded applications, with significantly reduced performance, making it difficult to achieve a true circular economy. Therefore, they cannot be widely used in ordinary car models.

[0004] In the field of nonwoven fabrics, existing spunbond needle-punched nonwoven fabrics mostly use single-component or multi-layer homogeneous material composites. When the basis weight reaches 2000 g / m² or higher, the following technical challenges arise during the compression molding process: First, uneven heating within the material can easily lead to delamination of the intermediate layers; second, extending the holding time to improve internal adhesion can cause the surface layer to peel or blister due to overheating; and third, the molding process window is narrow, making it difficult to control product quality. These defects limit the application of high-basis-weight nonwoven fabrics in the automotive molding parts field.

[0005] Therefore, developing a new type of nonwoven material that can achieve lightweighting, good molding performance, and is recyclable is of great practical significance and market value. Summary of the Invention

[0006] To address the shortcomings of existing technologies, this invention provides a polyester multi-component lightweight spunbond needle-punched nonwoven fabric, which has the advantages of significant lightweight effect, excellent molding performance, good physical and mechanical properties, and environmental recyclability. It solves the technical problems of easy internal delamination, easy surface peeling, and difficulty in controlling the molding cycle of high-grammage nonwoven fabrics during molding, as well as the high density and difficulty in recycling of traditional automotive non-metallic materials.

[0007] To achieve the above objectives, the present invention provides the following technical solution:

[0008] A polyester multi-component lightweight spunbond needle-punched nonwoven fabric, wherein the nonwoven fabric is formed by needle punching and shaping multiple layers of single web through cross-laying, and the areal density is in the range of 1000-4000 g / m², and the density is below 0.6 g / cm³.

[0009] The single network is a multi-component composite fiber network, and the fiber structure is one or a combination of two of the following: core-sheath type, peeled type, or parallel type; the fiber material is composed of PET and various COPET components, wherein the melting point range of the PET component is 220-260℃, and the melting point range of the COPET component is 150-215℃.

[0010] The single mesh is divided into three parts along the width direction: left, middle, and right. The COPET melting point of the fibers in the left and right parts is the same and higher than that of the COPET melting point of the fibers in the middle part. The COPET melting point of the fibers in the middle part is 10-40°C lower than that of the left and right parts.

[0011] Furthermore, the weight of the single net ranges from 80 to 300 g / m², and the width of the single net is 1.3 to 2.5 meters.

[0012] Furthermore, the width of the nonwoven fabric after cross-laying and needle punching is 2.5-5 meters.

[0013] Furthermore, the core layer of the core-sheath structure is high-melting-point PET, and the sheath layer is low-melting-point COPET; in the peelable or parallel structure, one component is high-melting-point PET, and the other component is low-melting-point COPET.

[0014] Furthermore, the single net is laid in layers by a cross-laying machine to form a composite net, with the laying direction forming a 90-degree angle with the output direction of the single net, so that the left, middle and right parts of the single net are distributed in layers in the thickness direction of the composite net.

[0015] Furthermore, in the composite mesh, the left and right parts of the single mesh are located on the upper and lower surfaces of the composite mesh, and the middle part is located in the middle layer of the composite mesh.

[0016] Furthermore, the nonwoven fabric is used for compression molding of automotive interior parts. During the compression molding process, the middle layer is preferentially melted and bonded due to the low melting point of low-melting-point COPET, while the surface layer maintains structural stability due to the high melting point of high-melting-point COPET.

[0017] Furthermore, the hot pressing cycle of the nonwoven fabric is shortened by 15-30% compared to ordinary nonwoven fabric of the same weight.

[0018] Furthermore, the nonwoven fabric is recyclable and can be recycled and granulated to be made into fibers or other molded products.

[0019] Furthermore, the nonwoven fabric is used for molded parts such as car roofs, coat racks, spare tire covers, trunk side panels, or bottom panels.

[0020] Compared with the prior art, the present invention provides a lightweight polyester multi-component spunbond needle-punched nonwoven fabric, which has the following beneficial effects:

[0021] 1. This polyester multi-component lightweight spunbond needle-punched nonwoven fabric has a density that can be controlled below 0.6 g / cm³. Compared with traditional automotive non-metallic materials (density above 0.9 g / cm³), the weight of components of the same size can be reduced by 20-30%. Calculated based on the use of 10 kg of traditional materials per vehicle, this can reduce weight by 2-3 kg. The cumulative effect of its application in multiple parts of the vehicle is significant, optimizing the power-to-weight ratio and reducing energy consumption.

[0022] 2. This polyester multi-component lightweight spunbond needle-punched nonwoven fabric, through a single-web partition design, concentrates low-melting-point COPET in the middle layer of the nonwoven fabric, while high-melting-point COPET is distributed in the upper and lower surface layers. During compression molding, the middle layer preferentially melts and bonds, solving the technical problem of easy delamination in high-basis-weight materials; at the same time, the surface layer, due to its higher melting point, avoids overheating and peeling, resulting in a wide molding process window and stable product quality. Tests have shown that the compression molding cycle for high-basis-weight materials above 2000g / m² is shortened by 15-30% compared to ordinary materials.

[0023] 3. This polyester multi-component lightweight spunbond needle-punched nonwoven fabric utilizes a long-fiber spunbond needle-punching process, resulting in strong fiber bonding and minimal anisotropy after cross-laying, leading to balanced mechanical properties. While achieving lightweight design, its tensile strength, tear strength, and impact resistance are comparable to traditional materials, meeting the requirements for automotive interior components.

[0024] 4. This multi-component lightweight polyester spunbond needle-punched nonwoven fabric, made from thermoplastic polyester materials, contains no non-recyclable components such as glass fiber. After disposal, it can be melt-granulated and reused, achieving material recycling and aligning with the development direction of green environmental protection and carbon emission reduction. Its application in the new energy vehicle sector can help reduce carbon emissions throughout the vehicle's entire lifecycle. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of the single-web forming structure of a polyester multi-component lightweight spunbond needle-punched nonwoven fabric according to the present invention.

[0026] Figure 2 This is a schematic diagram of the nonwoven fabric structure after forming of a polyester multi-component lightweight spunbond needle-punched nonwoven fabric according to the present invention.

[0027] In the diagram: 1 - Single network; 2 - Composite network; a - Left side of single network; b - Right side of single network; c - Middle part of single network. Detailed Implementation

[0028] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. 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.

[0029] Please see Figures 1 to 2 .

[0030] Example 1:

[0031] A1. Single-network preparation:

[0032] Multi-component composite fiber single web 1 is produced using the spunbond method. The fiber structure is core-sheath type, with a core layer of high-melting-point PET (melting point 255℃) and a sheath layer of low-melting-point COPET (melting point 190℃). Single web 1 is divided into three parts along its width: left, middle, and right. The COPET in the fibers of the left and right parts both have a melting point of 190℃, while the COPET in the fibers of the middle part has a melting point of 170℃, which is 20℃ lower than that of the left and right parts.

[0033] The weight of a single net is controlled at 150g / m², and the width of a single net is 1.8 meters.

[0034] A2. Cross-laid mesh:

[0035] The single mesh 1 is laid using a cross-laying machine, with the laying direction forming a 90-degree angle with the output direction of the single mesh 1. By controlling the number of laying layers, the total weight of the composite mesh 2 reaches 2000 g / m². During the laying process, the left, middle, and right parts of the single mesh 1 are naturally layered along the thickness direction of the composite mesh 2: the left and right parts are located on the upper and lower surface layers of the composite mesh 2, and the middle part is located in the middle layer of the composite mesh 2.

[0036] A3. Acupuncture shaping:

[0037] Composite mesh 2 is fed into a needle punching machine for needle punching reinforcement. The needle punching density is 20-50 needles / cm², and the needle punching depth is 2-8mm, resulting in a finished nonwoven fabric with a width of 3.2 meters.

[0038] A4. Performance Testing:

[0039] According to the test results, the nonwoven fabric prepared in this embodiment has a density of 0.58 g / cm³, a tensile strength (longitudinal direction) of 12.5 MPa, and a tear strength (longitudinal direction) of 85 N.

[0040] A5. Compression molding test:

[0041] The nonwoven fabric was cut into the shape of a car spare tire cover and placed in a mold for hot pressing at 210℃ for 60 seconds. Results showed that the product had good internal adhesion with no delamination; the surface was smooth and flat, without peeling or blistering defects; and the molding cycle was shortened by approximately 20% compared to traditional glass fiber reinforced materials.

[0042] It should be noted that the density of 0.6 g / cm³ mentioned above is the density after the nonwoven fabric is molded.

[0043] A6. Recovery Test:

[0044] After the waste material is crushed, it is extruded and granulated, and then remelted and spun. The resulting fiber retains more than 85% of its mechanical properties, proving that the material has good recyclability.

[0045] Example 2:

[0046] B1. Single-network preparation:

[0047] Multi-component composite fiber single web 1 is produced using the spunbond method. The fiber structure is parallel, with one component being high-melting-point PET (melting point 245℃) and the other component being low-melting-point COPET (melting point 175℃). The width of single web 1 is divided into sections: the left and right sections have a COPET melting point of 175℃, while the middle section has a COPET melting point of 155℃, which is 20℃ lower than the left and right sections.

[0048] The weight of a single net is controlled at 100g / m², and the width of a single net is 2.0 meters.

[0049] B2. Cross-laid mesh:

[0050] The single net 1 is laid using a cross-laying machine, and the number of layers is controlled so that the total weight of the composite net 2 reaches 3000g / m².

[0051] B3. Acupuncture shaping:

[0052] The needle-punching density is 40 needles / cm², the needle-punching depth is 4mm, and the finished width is 3.5 meters.

[0053] B4. Performance Testing:

[0054] In this embodiment, the nonwoven fabric has a density of 0.59 g / cm³, a tensile strength (longitudinal direction) of 13.2 MPa, and a tear strength (longitudinal direction) of 92 N.

[0055] B5. Compression molding test:

[0056] Non-woven fabric was used in automotive headliner molding parts, with a molding temperature of 200℃ and a holding time of 75 seconds. The product exhibited good internal adhesion, excellent surface quality, and a molding cycle approximately 18% shorter than that of traditional materials.

[0057] Example 3:

[0058] C1. Single-network preparation:

[0059] Multi-component composite fiber single web 1 is produced using the spunbond method. The fiber structure is peelable, and the peelable components are composite fibers consisting of high-melting-point PET (melting point 260℃) and low-melting-point COPET (melting point 200℃). Single web 1 is divided into sections: the COPET in the left and right sections both have a melting point of 200℃, while the COPET in the middle section has a melting point of 165℃, which is 35℃ lower than the left and right sections.

[0060] The weight of a single net is controlled at 190g / m², and the width of a single net is 2.4 meters.

[0061] C2, Cross-laid mesh:

[0062] The number of mesh layers was controlled to achieve a total weight of 3800 g / m² for composite mesh 2.

[0063] C3. Acupuncture shaping:

[0064] The needle-punching density is 40 needles / cm², the needle-punching depth is 5mm, and the finished width is 4.2 meters.

[0065] C4. Performance Testing:

[0066] In this embodiment, the nonwoven fabric has a density of 0.56 g / cm³, a tensile strength (longitudinal direction) of 14.0 MPa, and a tear strength (longitudinal direction) of 98 N.

[0067] C5. Compression molding test:

[0068] Non-woven fabric was used in automotive underbody panels, with a molding temperature of 195℃ and a holding time of 90 seconds. The product exhibits dense internal adhesion, good surface quality, and a molding cycle approximately 25% shorter than that of traditional materials.

[0069] Comparative example:

[0070] The material used is conventional homogeneous spunbond needle-punched nonwoven fabric, a single-component PET material with a basis weight of 2500 g / m², and a non-partitioned design. During compression molding, the holding time needs to be extended to more than 120 seconds to ensure internal adhesion, but slight peeling occurs on the surface at this time. The product density is 0.85 g / cm³, which is about 45% heavier than the embodiment of this invention.

[0071] In summary:

[0072] This invention, through a single-network, single-zone design, concentrates low-melting-point components in the middle layer of the nonwoven fabric, significantly improving the molding performance of high-basis-weight materials while achieving lightweight and recyclability, and can be widely used in the field of automotive interior parts.

[0073] It should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0074] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A lightweight polyester multi-component spunbond needle-punched nonwoven fabric, characterized in that, The nonwoven fabric is formed by needle punching and shaping multiple layers of single web (1) through cross-laying. The surface density is in the range of 1000-4000 g / m² and the density is below 0.6 g / cm³. The single network (1) is a multi-component composite fiber network. The fiber structure is one or a combination of two of the following: core-sheath type, peel type, or parallel type. The fiber material is composed of PET and various COPET components, wherein the melting point range of the PET component is 220-260℃, and the melting point range of the COPET component is 150-215℃. The single net (1) is divided into three parts along the width direction: left, middle and right. The COPET melting point of the fibers in the left and right parts is the same and higher than that of the COPET melting point of the fibers in the middle part. The COPET melting point of the fibers in the middle part is 10-40℃ lower than that of the left and right parts.

2. The polyester multi-component lightweight spunbond needle-punched nonwoven fabric according to claim 1, characterized in that, The weight range of the single net (1) is 80-300g / m², and the width of the single net (1) is 1.3-2.5 meters.

3. The polyester multi-component lightweight spunbond needle-punched nonwoven fabric according to claim 1, characterized in that, The width of the nonwoven fabric after cross-laying and needle punching is 2.5-5 meters.

4. The polyester multi-component lightweight spunbond needle-punched nonwoven fabric according to claim 1, characterized in that, The core layer of the core-sheath structure is high-melting-point PET, and the sheath layer is low-melting-point COPET; in the peelable or parallel structure, one component is high-melting-point PET, and the other component is low-melting-point COPET.

5. The polyester multi-component lightweight spunbond needle-punched nonwoven fabric according to claim 1, characterized in that, The single net (1) is laid by a cross-laying machine to form a composite net (2). The laying direction is at a 90-degree angle to the output direction of the single net (1), so that the left, middle and right parts of the single net (1) are distributed in layers in the thickness direction of the composite net (2).

6. The polyester multi-component lightweight spunbond needle-punched nonwoven fabric according to claim 1, characterized in that, In the composite net (2), the left and right parts of the single net (1) are located on the upper and lower surfaces of the composite net (2), and the middle part is located in the middle layer of the composite net (2).

7. The polyester multi-component lightweight spunbond needle-punched nonwoven fabric according to claim 1, characterized in that, The nonwoven fabric is used for molding automotive interior parts. During the molding process, the middle layer is preferentially melted and bonded due to the low melting point of COPET, while the surface layer maintains structural stability due to the high melting point of COPET.

8. The polyester multi-component lightweight spunbond needle-punched nonwoven fabric according to claim 1, characterized in that, The hot pressing cycle of the nonwoven fabric is 15-30% shorter than that of ordinary nonwoven fabric of the same weight.

9. The polyester multi-component lightweight spunbond needle-punched nonwoven fabric according to claim 1, characterized in that, The nonwoven fabric is recyclable and can be recycled and granulated to be made into fibers or other molded products.

10. The polyester multi-component lightweight spunbond needle-punched nonwoven fabric according to claim 1, characterized in that, The nonwoven fabric is used for molded parts such as car roofs, coat racks, spare tire covers, trunk side panels, or bottom panels.

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