High-strength high-toughness luggage compartment pad for vehicle and vehicle with same

Abstract

The application discloses a high-strength and high-toughness luggage compartment pad for a vehicle and a vehicle with the same, and belongs to the field of vehicle ornaments. The luggage compartment pad comprises, from top to bottom, a surface decoration layer, a reinforcing framework layer, a buffer energy-absorbing layer and an antiskid bottom layer which are sequentially stacked and bonded into an integrated whole. The reinforcing framework layer is a long-glass-fiber-reinforced polypropylene three-dimensional grid-shaped framework formed by injection molding, and comprises a plurality of longitudinal main ribs, a plurality of transverse main ribs, columnar reinforcing ribs and diagonal connecting ribs. The buffer energy-absorbing layer is a microcellular closed-cell foamed thermoplastic elastomer layer, and the foaming ratio is 5-15 times. The luggage compartment pad has the synergistic effects of high-strength bearing, high-toughness energy absorption, light weight and bidirectional antiskid, and overcomes the technical problem that the prior art products are difficult to have both high strength and high toughness.

Description

Technical Field

[0001] This invention relates to the field of automotive accessories, and in particular to a high-strength and high-toughness car trunk mat and a vehicle having the same. Background Technology

[0002] A trunk mat is an interior trim piece installed at the bottom of a car's trunk. It is mainly used to carry luggage and protect the trunk's interior, and also provides some cushioning and shock absorption to reduce impact damage to luggage and items caused by road bumps during vehicle operation.

[0003] There are three main types of existing car trunk mats: First, single rubber or TPE molded mats, which have decent toughness but low strength and are prone to permanent deformation; second, multi-layer composite mats with EPP or sponge as filling layers, which have good cushioning but low overall modulus and large deformation under concentrated loads; and third, PP honeycomb board or PP fiberglass board composite mats, which have high vertical compressive strength but insufficient bending stiffness, and often only emphasize rigidity while ignoring the need for high toughness. Summary of the Invention

[0004] This invention provides a high-strength, high-toughness car trunk mat and a vehicle incorporating it, which solves the problem that existing car trunk mats cannot simultaneously achieve strength, toughness, and lightweight.

[0005] To solve the above-mentioned technical problems, the present invention provides a high-strength and high-toughness car trunk mat, comprising a surface decorative layer, a reinforcing skeleton layer, a cushioning and energy-absorbing layer and an anti-slip bottom layer, which are stacked and bonded together from top to bottom; The reinforcing skeleton layer is an injection-molded long glass fiber reinforced polypropylene three-dimensional mesh skeleton, comprising: Multiple longitudinal main ribs extend along the length of the luggage pad; Multiple horizontal main ribs extend along the width of the luggage mat; The columnar reinforcing ribs are located at the intersection of the longitudinal main ribs and the transverse main ribs; The diagonal connecting ribs are connected at both ends to the adjacent columnar reinforcing ribs; The buffer energy-absorbing layer is a microporous closed-cell foamed thermoplastic elastomer layer with a foaming ratio of 5 to 15 times.

[0006] In a preferred embodiment of the present invention, the columnar reinforcing rib extends upward and downward beyond the thickness of the longitudinal main rib and the transverse main rib.

[0007] In a preferred embodiment of the present invention, the average pore diameter of the microporous closed-cell foamed thermoplastic elastomer layer is 50~200μm.

[0008] In a preferred embodiment of the present invention, the glass fiber in the long glass fiber reinforced polypropylene is a long glass fiber with a mass fraction of 20-40%.

[0009] In a preferred embodiment of the present invention, the adhesive layer is a hot melt adhesive film with a thickness of 0.05~0.2mm.

[0010] In a preferred embodiment of the present invention, the surface decorative layer is a needle-punched pile carpet fabric or a non-woven fabric, and its upper surface is provided with raised anti-slip strips and / or anti-slip particles.

[0011] In a preferred embodiment of the present invention, the anti-slip strips are arranged longitudinally or in a grid pattern, the spacing between adjacent anti-slip strips is 10~30mm, and the height of the anti-slip strips is 0.5~2mm.

[0012] In a preferred embodiment of the present invention, the anti-slip bottom layer is a thermoplastic elastomer layer, and its lower surface is provided with wavy or serrated anti-slip textures. The depth of the anti-slip textures is 0.3~1mm, and the texture spacing is 2~5mm.

[0013] In a preferred embodiment of the present invention, the thickness of the buffer energy-absorbing layer is 1.2 to 2.5 times the thickness of the reinforcing skeleton layer.

[0014] To address the aforementioned technical problems, the present invention also discloses a vehicle comprising the aforementioned luggage compartment mat.

[0015] The beneficial effects of the present invention are as follows: The present invention provides a high-strength and high-toughness car trunk mat and a vehicle having the same. The trunk mat achieves the synergistic effect of high strength load-bearing, high toughness energy absorption, lightweight and two-way anti-slip through a composite structure of a surface decorative layer, a long glass fiber reinforced polypropylene three-dimensional mesh skeleton containing main ribs, columnar reinforcing ribs and diagonal connecting ribs, a microporous closed-cell foamed elastomer buffer layer with a foaming ratio of 5 to 15 times and an anti-slip bottom layer. This overcomes the technical problem that existing products cannot achieve both high strength and high toughness. Attached Figure Description

[0016] Figure 1 This is a cross-sectional structural schematic diagram of a preferred embodiment 1 of the high-strength and high-toughness car trunk mat of the present invention; Figure 2 This is a top view schematic diagram of the surface decorative layer shown. Figure 3 This is a schematic diagram of a partial structure of the reinforced skeleton layer shown. Figure 4 This is a schematic diagram of the anti-slip base layer from below; The components in the attached diagram are labeled as follows: 10. Surface decorative layer; 11. Anti-slip strip; 20. Reinforcing skeleton layer; 21. Longitudinal main rib; 22. Transverse main rib; 23. Columnar reinforcing rib; 24. Diagonal connecting rib; 30. Buffer energy-absorbing layer; 40. Anti-slip bottom layer; 41. Anti-slip texture; 51. First adhesive layer, 52. Second adhesive layer, 53. Third adhesive layer. Detailed Implementation

[0017] The preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings, so that the advantages and features of the present invention can be more easily understood by those skilled in the art, thereby providing a clearer and more explicit definition of the scope of protection of the present invention.

[0018] The embodiments of the present invention include: Example 1 like Figure 1 As shown, this embodiment provides a high-strength and high-toughness car trunk mat, including a surface decorative layer 10, a reinforcing skeleton layer 20, a cushioning energy-absorbing layer 30, and an anti-slip bottom layer 40 stacked sequentially from top to bottom; a first adhesive layer 51, a second adhesive layer 52, and a third adhesive layer 53 are sequentially disposed between the surface decorative layer 10 and the reinforcing skeleton layer 20, between the reinforcing skeleton layer 20 and the cushioning energy-absorbing layer 30, and between the cushioning energy-absorbing layer 30 and the anti-slip bottom layer 40, and are bonded together as one unit by the first adhesive layer 51, the second adhesive layer 52, and the third adhesive layer 53. Specifically, the first adhesive layer 51, the second adhesive layer 52, and the third adhesive layer 53 are all EVA hot melt adhesive films, each with a thickness of 0.1 mm.

[0019] like Figure 2 As shown, the surface decorative layer 10 is a needle-punched pile carpet fabric with a thickness of 1.5 mm and a weight of 450 g / m². 2 Its surface has molded anti-slip strips 11, which are arranged longitudinally, with a height of 1mm, a width of 3mm, and a spacing of 20mm between adjacent anti-slip strips. The anti-slip strips create reliable friction with the luggage, preventing the luggage from sliding during sudden braking or bumps.

[0020] The reinforcing skeleton layer 20 is an injection-molded three-dimensional mesh skeleton of long glass fiber reinforced polypropylene, wherein the glass fiber in the long glass fiber reinforced polypropylene has a length of 15 mm and a mass fraction of 30%. The injection molding process is as follows: the long glass fiber reinforced polypropylene granules are dried at 90℃ for 4 hours, and then added to the injection molding machine. The injection temperature settings are: barrel section 1 200℃, section 2 210℃, section 3 220℃, nozzle 215℃; mold temperature 60℃; injection pressure 80MPa; holding pressure 60MPa, holding time 15 seconds; cooling time 30 seconds.

[0021] Specifically, such as Figure 3 As shown, the long glass fiber reinforced polypropylene three-dimensional mesh skeleton includes: Multiple longitudinal main ribs 21 extend along the length of the luggage pad; Multiple transverse main ribs 22 extend along the width of the luggage pad; The columnar reinforcing rib 23 is located at the intersection of the longitudinal main rib 21 and the transverse main rib 22, and extends upward and downward beyond the thickness of the longitudinal main rib 21 and the transverse main rib 22. The diagonal connecting rib 24 connects to the adjacent columnar reinforcing ribs 23 at both ends. The diagonal connecting rib 24 enhances the torsional stiffness and overall stability of the mesh skeleton, preventing rhomboid deformation under stress and further improving bending resistance. The longitudinal main ribs 21, transverse main ribs 22, columnar reinforcing ribs 23, and diagonal connecting ribs 24 together constitute a spatial mesh structure, significantly improving the overall bending strength and bending modulus of the luggage mat.

[0022] The buffer energy-absorbing layer 30 is a microporous closed-cell foamed thermoplastic elastomer layer, prepared from thermoplastic polyurethane (TPU) foam sheets using supercritical CO2 physical foaming technology. The foaming ratio is 10 times, the average cell diameter is 100 μm, and the thickness is 7 mm. The specific foaming process is as follows: TPU granules with a hardness of 85A and a melt index of 15 g / 10 min are mixed with 0.5 wt% of nucleating agent nano-talc powder and added to a twin-screw extruder. The extruder temperature settings are: stage 170℃, stage 2180℃, stage 3190℃, stage 4195℃, and die head 200℃. Supercritical CO2 is injected into the front of the die head at a rate of 3% of the resin mass. After the melt is extruded through the sheet die, it foams in the depressurization zone, then cools and shapes it using a three-roll calender, and finally pulls and winds it to obtain a microporous closed-cell foamed TPU sheet with a foaming ratio of 10 times and a thickness of 7 mm. The average cell diameter was measured to be 95 μm using a cell image analyzer, with a closed-cell rate >90%. The sheet was cut to the same dimensions as the reinforcing skeleton layer. This microporous closed-cell structure absorbs and dissipates impact energy through the elastic compression deformation of the cells upon impact, and quickly rebounds to its original position after the impact.

[0023] like Figure 4 As shown, the anti-slip bottom layer 40 is a thermoplastic elastomer layer with a thickness of 1 mm and a Shore hardness of 65A. Its lower surface is embossed with serrated anti-slip patterns 41. Specifically, the depth of the anti-slip patterns 41 is 0.5 mm and the spacing between the patterns is 3 mm. The static friction between the anti-slip patterns and the trunk carpet can prevent the trunk mat itself from shifting inside the vehicle.

[0024] The preparation method of the high-strength and high-toughness car trunk mat in this embodiment is as follows: according to Figure 1The layering sequence shown, from bottom to top, is as follows: anti-slip base layer 40 (anti-slip textured surface facing down), third adhesive layer 53, buffer energy-absorbing layer 30, second adhesive layer 52, reinforcing skeleton layer 20, first adhesive layer 51, and surface decorative layer 10 (anti-slip strip side facing up). The stacked blanks are fed into a flatbed press and pressed for 60 seconds under the conditions of an upper mold temperature of 150℃, a lower mold temperature of 170℃, and a mold closing pressure of 1.2MPa. After pressing, cooling water circulation is turned on, and the blanks are cooled to below 80℃ while maintaining pressure. The molded part is then removed, and excess flash is trimmed with an edge trimmer. The edges are then heat-sealed to prevent delamination. The final product has the following characteristics: Figure 1 The finished product of the layered structure of the luggage mat shown.

[0025] The temperature gradient is created by the temperature difference between the upper and lower templates of the flatbed press, which protects the surface decorative layer fabric and ensures that the anti-slip bottom layer flows fully.

[0026] During the molding process, the columnar reinforcing ribs 23 protruding from the upper and lower parts of the reinforcing skeleton layer 20 compress the first adhesive layer 51 and the surface decorative layer 10, while the lower protrusion compresses the second adhesive layer 52 and the buffer energy-absorbing layer 30, causing local deformation and embedding of each layer to form an anchored and interlocking structure. At the same time, the EVA hot melt adhesive film melts and flows, tightly bonding each layer together. Due to the higher temperature of the lower mold, the TPE material of the anti-slip bottom layer 40 has enhanced fluidity, resulting in clear anti-slip texture. The lower temperature of the upper mold ensures that the polyester fibers of the surface decorative layer 10 are not damaged, maintaining a good appearance.

[0027] Example 2 The difference from Example 1 is that the glass fiber length in the long glass fiber reinforced polypropylene is 10 mm and the mass fraction is 25%.

[0028] The energy-absorbing buffer layer is made of TPE material with a foaming ratio of 8 times, an average cell diameter of 120μm, and a thickness of 6mm.

[0029] The columnar reinforcing ribs are flush with the surface of the ribs.

[0030] The surface decorative layer has anti-slip strips arranged in a grid pattern with a spacing of 25mm×25mm and a height of 0.8mm.

[0031] The anti-slip bottom layer has a wavy texture with a depth of 0.8mm and a spacing of 4mm.

[0032] Molding temperature: upper mold plate 140℃, lower mold plate 160℃; pressure 1.0MPa; holding time 50 seconds.

[0033] Example 3 The difference from Example 1 is that the glass fiber length in the reinforcing skeleton layer is 25 mm and the mass fraction is 40%.

[0034] The energy-absorbing buffer layer has a foaming ratio of 5 times, an average cell diameter of 60 μm, and a thickness that is 2.5 times that of the skeleton layer.

[0035] Molding temperature: upper mold plate 160℃, lower mold plate 180℃; pressure 1.5MPa; holding time 90 seconds.

[0036] The performance of the car trunk mats prepared in Examples 1-3 was tested, and the test standards were as follows: Flexural strength / modulus: GB / T 9341; Impact energy absorption: Drop hammer impact test, 500g hammer, impact velocity 4m / s, record the absorbed energy; Compression set: GB / T 6669; Friction coefficient: horizontal tension method. The results are shown in Table 1 below.

[0037] Table 1 Comparative Example 1 The difference from Example 1 is that no composite buffer energy-absorbing layer is used. The specific stacking order is as follows: from bottom to top, the anti-slip bottom layer 40, the third adhesive layer 53, the reinforcing skeleton layer 20, the first adhesive layer 51, and the surface decoration layer 10 are placed in sequence. The second adhesive layer 52 and the buffer energy-absorbing layer 30 are not provided. The rest is the same as in Example 1.

[0038] Comparative Example 2 The difference from Embodiment 1 is that no reinforcing skeleton layer is provided. The specific stacking order is as follows: from bottom to top, the anti-slip bottom layer 40, the third adhesive layer 53, the buffer energy-absorbing layer 30, the first adhesive layer 51, and the surface decoration layer 10 are placed in sequence. The second adhesive layer 52 and the reinforcing skeleton layer 20 are not provided. The rest is the same as in Embodiment 1.

[0039] Comparative Example 3 The difference from Example 1 is that the reinforcing skeleton layer adopts a planar grid skeleton without columnar reinforcing ribs, that is, there are no vertically extending columnar reinforcing ribs at the intersection of the longitudinal main ribs and the transverse main ribs, and no diagonal connecting ribs are provided. The other layers and processes are the same as in Example 1.

[0040] The interlayer peel strength of the samples from Example 1 and Comparative Example 3 was tested in accordance with GB / T 2791-1995 "Adhesives T Peel Strength Test Method".

[0041] Test results: Example 1 showed a flexural strength of 212 MPa, impact energy of 38.5 J, compressive settling of 2.8%, and interlaminar peel strength of 3.8 N / mm; Comparative Example 3 showed a flexural strength of 195 MPa, impact energy of 29.8 J, compressive settling of 4.5%, and interlaminar peel strength of 2.1 N / mm. It is evident that the anchoring and interlocking structure of the columnar reinforcing ribs improves interlaminar peel resistance by approximately 81%.

[0042] The performance of the car trunk mats prepared in Example 1, Comparative Example 1, Comparative Example 2 and Comparative Example 3 were tested, and the results are shown in Table 2 below.

[0043] Table 2 As can be seen from the data in Table 2, although the skeleton reinforcement layer alone has high strength, it has poor impact absorption capacity and large permanent deformation; while the buffer energy absorption layer alone has extremely low strength and cannot bear heavy objects.

[0044] 1. The flexural strength of the luggage mat of the present invention can reach 185~245 MPa, and the flexural modulus can reach 4.2~6.0 GPa. It can reliably withstand the long-term static load of heavy objects in the luggage and the dynamic load during the driving process, avoiding excessive deformation or damage.

[0045] 2. The impact absorption energy of the luggage pad of the present invention can reach 31~42J, effectively protecting luggage from vibration and impact damage; at the same time, the reinforced skeleton layer and the buffer energy absorption layer form an anchoring and interlocking structure through the vertical extension of columnar reinforcing ribs, which further improves the overall structure's ability to work together under dynamic impact and prevents premature separation between layers.

[0046] 3. The reinforcing skeleton layer adopts a three-dimensional hollow mesh design, which significantly reduces the amount of solid material used; the buffer energy-absorbing layer is a microporous foam material with a density as low as 0.08~0.24 g / cm³. The overall areal density can be controlled between 2.6~3.1 kg / m², which is 20~40% lighter than traditional rubber pads or solid plastic pads, in line with the trend of automotive lightweighting and helps to reduce the vehicle's fuel or electricity consumption.

[0047] In summary, this invention achieves comprehensive performance of high strength, high energy absorption, low permanent deformation, and lightweight by employing multiple technical means, including rigid frame load-bearing, flexible foam energy absorption, anchoring and interlocking reinforcement, and bidirectional anti-slip properties. Experimental data shows that its flexural strength reaches 185~245MPa, impact energy absorption reaches 31~42J, compression set is ≤3.5%, and areal density is only 2.6~3.1 kg / m². It has significant advantages in comprehensive load-bearing and cushioning performance and can meet the stringent requirements of high strength and high toughness for automotive trunk mats.

[0048] The above description is merely an embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural or procedural transformations made based on the content of the present invention's specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of the present invention.

Claims

1. A high-strength, high-toughness car trunk mat, characterized in that, It includes a surface decorative layer, a reinforcing skeleton layer, a buffer energy-absorbing layer, and an anti-slip bottom layer, which are stacked and bonded together from top to bottom; An adhesive layer is provided between the surface decoration layer and the reinforcing skeleton layer, between the reinforcing skeleton layer and the buffer energy absorption layer, and between the buffer energy absorption layer and the anti-slip bottom layer, and each layer is bonded together by the adhesive layer. The reinforcing skeleton layer is an injection-molded long glass fiber reinforced polypropylene three-dimensional mesh skeleton, comprising: Multiple longitudinal main ribs extend along the length of the luggage pad; Multiple horizontal main ribs extend along the width of the luggage mat; The columnar reinforcing ribs are located at the intersection of the longitudinal main ribs and the transverse main ribs; The diagonal connecting ribs are connected at both ends to the adjacent columnar reinforcing ribs; The buffer energy-absorbing layer is a microporous closed-cell foamed thermoplastic elastomer layer with a foaming ratio of 5 to 15 times.

2. The high-strength, high-toughness car trunk mat according to claim 1, characterized in that, The columnar reinforcing ribs extend upwards and downwards beyond the thickness of the longitudinal and transverse main ribs.

3. The high-strength, high-toughness car trunk mat according to claim 1 or 2, characterized in that, The average pore diameter of the microporous closed-cell foamed thermoplastic elastomer layer is 50~200μm.

4. The high-strength, high-toughness car trunk mat according to claim 1, characterized in that, The glass fibers in the long glass fiber reinforced polypropylene are long glass fibers, with a mass fraction of 20-40%.

5. The high-strength, high-toughness car trunk mat according to claim 1, characterized in that, The adhesive layer is a hot melt adhesive film with a thickness of 0.05~0.2mm.

6. The high-strength, high-toughness car trunk mat according to claim 1, characterized in that, The surface decorative layer is a needle-punched pile carpet fabric or a non-woven fabric, and its upper surface is provided with raised anti-slip strips and / or anti-slip particles.

7. The high-strength, high-toughness car trunk mat according to claim 6, characterized in that, The anti-slip strips are arranged longitudinally or in a grid pattern, with a spacing of 10-30mm between adjacent anti-slip strips and a height of 0.5-2mm.

8. The high-strength, high-toughness car trunk mat according to claim 1, characterized in that, The anti-slip bottom layer is a thermoplastic elastomer layer, and its lower surface is provided with wavy or serrated anti-slip textures. The depth of the anti-slip textures is 0.3~1mm, and the spacing between the textures is 2~5mm.

9. The high-strength, high-toughness car trunk mat according to claim 1, characterized in that, The thickness of the buffer energy-absorbing layer is 1.2 to 2.5 times the thickness of the reinforcing skeleton layer.

10. A vehicle, characterized in that, Includes the luggage mat as described in any one of claims 1-9.

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