High-resilience cushioning floor and method of making same

Abstract

The application provides a high-resilience cushioning floor and a preparation method thereof. The floor comprises, from top to bottom, an upper hard layer, a composite core layer and a lower hard layer. The composite core layer comprises a honeycomb framework, a reinforcing material and a foamed filling body. One or more transverse through holes are arranged on the side wall of the honeycomb cell of the honeycomb framework, and the reinforcing material is filled in the transverse through holes. The foamed filling body is filled in the cell and the transverse through hole of the honeycomb framework, and the reinforcing material is covered in the foamed filling body. The reinforcing material and the foamed filling body are integrally solidified to form a three-dimensional network structure. The application forms a firm mechanical lock between the reinforcing material and the foamed filling body after solidification. Meanwhile, the foamed filling body forms a transverse connecting rib between adjacent cells through the transverse through hole, so that the interface between the foamed body and the honeycomb framework is no longer a simple plane contact, but a complex interface with a three-dimensional interlocking feature.

Description

Technical Field

[0001] This invention relates to the field of flooring technology, and in particular to a high-resilience shock-absorbing floor and its preparation method. Background Technology

[0002] High-resilience cushioning flooring is a type of flooring material widely used in sports venues, gyms, school playgrounds, and other similar locations. Its core function is to provide safety protection for athletes while meeting their athletic performance requirements. Existing high-resilience cushioning flooring typically consists of two rigid layers and a honeycomb core in between. The honeycomb core is usually filled with polyurethane (PU) or other foam materials to meet both the needs of cushioning and energy absorption and rebound support.

[0003] Existing honeycomb filling technologies mainly employ injection or casting methods to fill the honeycomb cells with foamed material. For example, Chinese patent CN212453318U discloses a honeycomb core material comprising a honeycomb board and a plurality of foamed layers, each foamed layer filling each honeycomb cell, and the foamed layers are tightly connected to the walls of the honeycomb cells, wherein the foamed layers are formed by injection molding with a rigid foaming agent. Chinese patent CN111645884A discloses a frame honeycomb structure, in which a rectangular hole penetrating the wall is set at the center of each wall of the honeycomb core, forming a symmetrical frame-like wall structure, which can effectively solve the problem of unfavorable debris cloud diffusion due to the channeling effect in honeycomb structures, while giving the honeycomb structure relatively high structural strength. CN212358997U discloses a closed honeycomb foamed layer structure for PVC sports flooring, in which the core layer fills the interior of the hexagonal support structure and fills the space between the upper and lower support layers, making the rebound direction upward, and the elasticity of the entire foamed layer more obvious.

[0004] However, existing technologies still have the following drawbacks: In existing honeycomb filling structures, the foam material only fills each individual honeycomb cell, and the foam material between cells is not interconnected. Under localized point loads (such as high heels, furniture legs, or impacts from heels during exercise), the foam material in the load-concentrated area lacks lateral support from adjacent cells, making it prone to permanent crushing or denting. Furthermore, thermoplastic honeycomb materials such as polypropylene (PP) have low surface energy and strong chemical inertness, resulting in only physical contact or weak chemical adsorption with polyurethane foam materials, leading to limited interfacial bonding. During the use of high-resilience shock-absorbing flooring, the floor needs to withstand long-term, repeated impact loads. Repeated shear stress at the interface can easily cause the foam material to debond from the honeycomb wall, forming localized voids. This not only produces abnormal noise but also leads to a rapid decline in shock-absorbing performance. Summary of the Invention

[0005] To address the aforementioned issues, this invention utilizes a lateral through-hole design in the honeycomb skeleton, targeted implantation of reinforcing materials, and three-dimensional network molding of the foam filler to construct an integrated composite core structure of "skeleton-anchor point-matrix." This connects the isolated "columnar buffer units" in traditional honeycomb structures into an "integrated network" through lateral through-holes and reinforcing materials, enabling the load to be transmitted and dispersed in both lateral and vertical directions within the core layer. This simultaneously enhances the structure's impact resistance (shock absorption) and energy return (rebound).

[0006] Specifically, the present invention provides a high-resilience shock-absorbing floor, comprising an upper rigid layer, a composite core layer, and a lower rigid layer arranged sequentially from top to bottom. The composite core layer comprises a honeycomb skeleton, a reinforcing material, and a foam filler. One or more transverse through-holes penetrating the wall are provided on the sidewalls of the honeycomb cells of the honeycomb skeleton, and the reinforcing material is filled in the transverse through-holes. The foam filler fills the cells of the honeycomb skeleton and the transverse through-holes, and encapsulates the reinforcing material therein. The reinforcing material and the foam filler are integrally cured to form a three-dimensional network structure.

[0007] Preferably, the height of the honeycomb skeleton is 10-20 mm, the pore diameter is 8-10 mm, and the wall thickness is 0.2-0.5 mm; the transverse through holes are spaced apart in the horizontal direction with a spacing of 5-10 mm and a diameter of 1-2 mm.

[0008] Preferably, the amount of reinforcing material added accounts for 0.5-2.0 wt% of the total weight of the foaming raw material.

[0009] Preferably, the honeycomb skeleton material is polypropylene or UV-induced graft polymerization modified polypropylene, the reinforcing material is chopped fiber composite resin material or thermoplastic polyurethane elastomer; the foam filler is polyurethane foam material; and the upper rigid layer and the lower rigid layer are each independently selected from rigid polyvinyl chloride sheet or thermoplastic polyurethane sheet.

[0010] A method for preparing a high-resilience shock-absorbing floor includes the following steps: A honeycomb skeleton is provided, and transverse through holes are opened on the wall surface of the honeycomb lattice of the honeycomb skeleton; reinforcing material is implanted into the transverse through holes, and foaming material is filled into the honeycomb lattice and transverse through holes, or the reinforcing material is dispersed in the foaming material and filled together with the foaming material; the foaming material is foamed and cured to form a foamed filler, and a composite core layer is obtained. The upper hard layer and the lower hard layer are respectively laminated onto the upper and lower surfaces of the composite core layer.

[0011] Preferably, the transverse through hole is created by laser drilling or mechanical punching.

[0012] Preferably, after creating the transverse through hole, the following steps are also included: Immerse the honeycomb skeleton in a 0.1-0.3 mol / L benzophenone / anhydrous ethanol solution for 1-2 hours, then remove and dry for 20-40 minutes. The dried honeycomb skeleton was immersed in an acrylic acid solution with a concentration of 10-30 vol%, and graft polymerization was carried out under ultraviolet light irradiation at a wavelength of 365 nm and a power of 100-200 W for 10-30 min. The ultraviolet light irradiation was carried out in a nitrogen atmosphere.

[0013] Preferably, the foaming material is filled into the honeycomb pores and transverse through-holes using a vacuum-assisted injection method. The vacuum degree of the vacuum-assisted injection method is -0.09 to -0.098 MPa. Ultrasonic vibration is applied to assist in venting during the injection process, with an ultrasonic frequency of 20–40 kHz.

[0014] Preferably, a pressure of 0.5–1.5 MPa is applied 10–20 minutes after the start of foaming and curing, and the pressure is maintained for 5–10 minutes.

[0015] Preferably, the step of bonding the upper hard layer and the lower hard layer to the upper and lower surfaces of the composite core layer respectively includes: An epoxy resin film is placed on the upper and lower surfaces of the composite core layer, followed by an upper and lower rigid layer. The core is then placed in a hot press and held at 100-120℃ and 1.0-1.5 MPa for 40-60 seconds.

[0016] Beneficial effects

[0017] Compared with the prior art, the present invention has the following beneficial effects: This invention involves filling transverse through-holes with reinforcing material, which is then completely encapsulated by a foam filler. After curing, a strong mechanical bond is formed between the reinforcing material and the foam filler (the reinforcing material forms physical anchor points within the holes). Simultaneously, the foam filler forms transverse connecting ribs between adjacent cells through the transverse through-holes, transforming the interface between the foam and the honeycomb skeleton from a simple planar contact into a complex interface with three-dimensional interlocking characteristics. This structural design significantly improves the interfacial peel strength, effectively preventing delamination, hollowing, and debonding problems under long-term repeated impacts. The three-dimensional network structure formed by the foam filler allows the load to be quickly distributed to adjacent cells through the transverse connecting ribs, avoiding stress concentration. Furthermore, the reinforcing material within the transverse through-holes provides additional rigid support, significantly improving the floor's resistance to indentation and permanent deformation, and extending its service life. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the structure of the high-resilience shock-absorbing floor provided by the present invention; Figure 2This is a schematic flowchart illustrating the preparation method of the high-resilience shock-absorbing floor provided by the present invention. Detailed Implementation

[0019] The preferred embodiments of the present invention are described below. It should be understood that the preferred embodiments described herein are for illustration and explanation only and are not intended to limit the present invention.

[0020] The present invention will now be described in conjunction with embodiments.

[0021] like Figure 1 As shown, this invention provides a high-resilience, shock-absorbing floor, comprising an upper rigid layer 1, a composite core layer 2, and a lower rigid layer 3 arranged sequentially from top to bottom. The composite core layer 2 includes a honeycomb skeleton, reinforcing material, and foam filler. One or more transverse through-holes 21 are provided on the sidewalls of the honeycomb cells of the honeycomb skeleton. The reinforcing material fills the transverse through-holes 21. The foam filler fills the cells and transverse through-holes of the honeycomb skeleton, and encapsulates the reinforcing material therein. The reinforcing material and the foam filler are integrally cured to form a three-dimensional network structure.

[0022] Through the transverse through-holes in the honeycomb skeleton, the foam filler forms transverse connecting ribs between adjacent cells, connecting the originally isolated vertical foam columns into a whole; simultaneously, reinforcing material is pre-filled within the transverse through-holes, which is completely encapsulated during the curing process of the foam filler, forming an integrated three-dimensional network structure with the foam matrix. Specifically: The elastic modulus of reinforcing materials (such as chopped fiber composite resins or thermoplastic polyurethane elastomers) is much higher than that of the foam matrix. When the core layer is compressed, the reinforcing materials located within the through-pores resist deformation first, playing a role in "stress concentration and dispersion" and "deformation constraint". At the same time, the surface of the reinforcing material can form mechanical or chemical bonds with the foam matrix, significantly improving the interfacial bonding strength.

[0023] Preferably, the height of the honeycomb skeleton refers to the axial length of the honeycomb cells, i.e., the thickness dimension of the floor composite core layer, and its value ranges from 10 to 20 mm. The diameter of the honeycomb cells refers to the distance between opposite sides of a regular hexagonal cell, and its value ranges from 8 to 10 mm, with a wall thickness of 0.2 to 0.5 mm. The transverse through holes are spaced apart in the horizontal direction with a spacing of 5 to 10 mm, and the diameter of the transverse through holes is 1 to 2 mm. The through holes formed on the sidewalls of each honeycomb cell of the honeycomb skeleton have their channel axes parallel to the floor plane (i.e., perpendicular to the axial direction of the honeycomb cells), and on the same honeycomb wall surface or between adjacent honeycomb wall surfaces, the through holes are arranged at a certain distance from each other along the extension direction of the honeycomb wall.

[0024] Preferably, the amount of reinforcing material added accounts for 0.5–2.0 wt% of the total weight of the foaming raw material. The amount of reinforcing material added is a key process parameter that determines the reinforcement effect of the three-dimensional network. This invention limits the amount of reinforcing material added to 0.5–2.0 wt% of the total weight of the foaming raw material. The principle is as follows: Within the range of 0.5–2.0 wt%, the reinforcing material can form a good suspension dispersion in the foaming raw material. During vacuum infusion, it enters the transverse pores with the fluid and forms a randomly oriented three-dimensional fiber network or elastomer aggregate within the pores. After curing, this network forms a "rigid-flexible" composite structure with the foam matrix, maintaining the elasticity of the foam while providing local reinforcement.

[0025] Preferably, the honeycomb skeleton material is polypropylene or UV-induced graft polymerization modified polypropylene, the reinforcing material is chopped fiber composite resin material or thermoplastic polyurethane elastomer; the foam filler is polyurethane foam material; and the upper rigid layer and the lower rigid layer are each independently selected from rigid polyvinyl chloride sheet or thermoplastic polyurethane sheet.

[0026] Polypropylene (PP) is a commonly used material for thermoplastic honeycomb structures, possessing advantages such as low density, low cost, easy processing, and resistance to chemical corrosion. However, PP has low surface energy and strong chemical inertness, and its interfacial bonding with polyurethane foam is limited to van der Waals forces. Therefore, this invention further employs UV-induced graft polymerization to modify polypropylene (PP-g-AA). The modification process covalently introduces carboxyl groups (—COOH) onto the PP surface. These carboxyl groups can chemically react with isocyanate groups (—NCO) in the polyurethane foam to form amide ester bonds or urea-formaldehyde bonds, transforming the interfacial bonding from physical adsorption to covalent bonding, significantly improving the bonding strength.

[0027] like Figure 2 As shown, the preparation process provided by the present invention includes the following steps: providing a honeycomb skeleton and opening transverse through holes on the honeycomb cell wall surface of the honeycomb skeleton; implanting reinforcing material into the transverse through holes; filling the honeycomb cells and transverse through holes with foaming material, or dispersing the reinforcing material in the foaming material and filling it together with the foaming material; allowing the foaming material to foam and solidify to form a foamed filler, thereby obtaining a composite core layer; and bonding an upper rigid layer and a lower rigid layer to the upper and lower surfaces of the composite core layer, respectively.

[0028] First, a honeycomb skeleton is provided, and transverse through holes are formed on the wall surface of the honeycomb cells. These transverse through holes can be formed using laser drilling or mechanical punching.

[0029] Ultraviolet laser drilling process: This process uses a 355nm ultraviolet laser to remove material through photochemical ablation. The high energy of ultraviolet photons (approximately 3.5eV) directly breaks the covalent bonds in the PP molecular chains, causing the material to be removed in a vaporized form with almost no thermal impact. Laser drilling can achieve arbitrary hole shapes and variable spacing, making it suitable for R&D and small-batch production. Optimal process parameters: power 10–25W, repetition rate 40–100kHz, scanning speed 100–500mm / s, and nitrogen as the auxiliary gas.

[0030] Mechanical punching process: Using customized punching dies, all transverse through holes are punched out on the honeycomb panel in one go. The punch diameter matches the designed hole diameter (1–2 mm), and the single-sided gap between the punch and the blanking hole is controlled within 0.01–0.03 mm. During punching, the honeycomb panel is fixed between the dies, and the array of punches presses down simultaneously to punch away the honeycomb wall material.

[0031] Preferably, the honeycomb skeleton is immersed in a 0.1-0.3 mol / L benzophenone / anhydrous ethanol solution for 1-2 h, then removed and dried for 20-40 min; the dried honeycomb skeleton is then immersed in a 10-30 vol% acrylic acid solution and subjected to graft polymerization under ultraviolet light irradiation at a wavelength of 365 nm and a power of 100-200 W for 10-30 min, wherein the ultraviolet light irradiation is carried out in a nitrogen atmosphere.

[0032] PP honeycomb was immersed in a BP / anhydrous ethanol solution, and BP molecules were deposited on the PP surface through physical adsorption. Anhydrous ethanol, used as a solvent, evaporated rapidly, resulting in a uniform thin layer of BP on the PP surface after drying. Under 365nm ultraviolet light irradiation, BP molecules generated PP surface free radicals and a half-pinacol free radical. These PP surface free radicals then initiated free radical polymerization of the double bonds in the surrounding acrylic acid (AA) monomers, forming covalently linked polyacrylic acid (PAA) chains. Because the PP surface free radicals are located on the solid surface, the polymerization reaction mainly occurred within the thin PP surface layer. The generated PAA chains were covalently anchored to the PP surface. After washing, only the covalently linked PAA chains remained on the PP surface, and carboxyl groups (-COOH) were successfully introduced.

[0033] Then, the foaming material is filled into the honeycomb cells and transverse through-holes, or the reinforcing material is dispersed in the foaming material and filled together with the foaming material.

[0034] The first method (pre-implantation method): Pre-formed reinforcing materials (such as fiber bundles, micro-pins, or pre-formed columns) are first implanted into the transverse through-holes using manual or automated equipment, and then the foaming material is poured in. The advantage of this method is that the position and orientation of the reinforcing material can be precisely controlled, making it particularly suitable for high-end products requiring high localized reinforcement effects. After the reinforcing material is pre-positioned within the through-hole, the subsequently poured foaming material completely encapsulates it.

[0035] The second method (blending method) involves pre-dispersing reinforcing materials such as chopped fibers in the polyol component of the foaming raw material. During injection, these fibers enter the honeycomb pores and transverse through-holes along with the foaming raw material. This method is advantageous due to its simple process, lack of need for additional implantation equipment, high production efficiency, and suitability for mass production. During vacuum injection, the fibers enter the transverse through-holes with the fluid, forming a randomly oriented three-dimensional fiber network within the pores, achieving the same reinforcing effect.

[0036] The foaming material is filled into the honeycomb pores and transverse through holes using a vacuum-assisted injection method. The vacuum degree of the vacuum-assisted injection method is -0.09 to -0.098 MPa. Ultrasonic vibration is applied to assist in venting during the injection process, with an ultrasonic frequency of 20–40 kHz.

[0037] The foaming material can be an existing polyurethane (PU) foaming system, for example, including the following components by weight: (1) Polyol: 100 parts by weight, selected from polyether polyol or polyester polyol. (2) Isocyanate: 80–90 parts by weight, selected from diphenylmethane diisocyanate (MDI), toluene diisocyanate (TDI) or its polymethylene polyphenyl polyisocyanate (PAPI). (3) Blowing agent: 0.5–1.0 parts by weight, selected from water or physical blowing agents, preferably water. (4) Catalyst: 0.3–0.8 parts by weight, composed of amine catalyst and organotin catalyst. (5) Crosslinking agent: 0.5–2.0 parts by weight, selected from diethanolamine, triethanolamine or ethylene glycol, preferably diethanolamine. (6) Surfactant: 0.3–1.0 parts by weight, selected from organosilicon surfactants, preferably polyether-modified polysiloxane (such as L-580).

[0038] The honeycomb lattice structure has numerous independent small chambers. During traditional atmospheric pressure casting, air is trapped within the lattice. When the foaming material flows under gravity or pressure difference, the air cannot escape in time, easily leading to air bubble retention and incomplete filling. Vacuum-assisted casting establishes a negative pressure (-0.09 to -0.098 MPa) within the mold, pre-extracting air from the lattice. When the foaming material is injected from the bottom, it rapidly fills the cavity from bottom to top and from the inside out under the pressure difference, completely eliminating air. Applying ultrasonic vibration at 20–40 kHz during the casting process utilizes the cavitation effect and mechanical vibration generated by ultrasound in the liquid to cause air bubbles adhering to the honeycomb walls and the inner walls of the pores to detach and float to the surface. Ultrasonic vibration also reduces the viscosity of the foaming material, improves its flowability, and facilitates the material's entry into the tiny transverse pores (1–2 mm in diameter).

[0039] Then, the foaming material is foamed and cured to form a foamed filler, resulting in a composite core layer. Preferably, a pressure of 0.5–1.5 MPa is applied 10–20 minutes after the start of foaming and curing, and the pressure is maintained for 5–10 minutes.

[0040] Finally, the steps of bonding the upper and lower rigid layers to the upper and lower surfaces of the composite core layer respectively include: placing an epoxy resin film on each of the upper and lower surfaces of the composite core layer, then placing the upper and lower rigid layers on top, and then placing it in a hot press at a temperature of 100-120℃ and a pressure of 1.0-1.5 MPa for 40-60 seconds. The prepared product exhibits a peel strength ≥2.0 N / mm between the rigid layer and the composite core layer, with no bubbles or delamination. The surface flatness of the flooring is ≤0.5 mm / m, meeting the surface flatness requirements for sports flooring.

[0041] The epoxy resin film is a solid film at room temperature, but melts when heated to 100–120℃, exhibiting good fluidity and wettability. Under pressure, the molten epoxy resin penetrates into the openings of the foam and the micro-gaps of the honeycomb skeleton on the surface of the composite core layer, forming an "anchoring" structure after curing, which firmly bonds the rigid layer to the core layer.

[0042] Example 1

[0043] 1. Materials and Parameters Honeycomb skeleton: Polypropylene (PP) honeycomb, height 10 mm, cell diameter 8 mm, wall thickness 0.2 mm, size 300 mm × 300 mm.

[0044] Horizontal through holes: Ultraviolet laser drilling, 1.0 mm in diameter, 5 mm in horizontal spacing, with one through hole on the side wall of each grid.

[0045] Reinforcing material: Short-cut carbon fiber (T300 grade), 3 mm in length and 5 μm in diameter, added at a rate of 0.5 wt% of the total weight of the foaming raw material.

[0046] UV grafting: 0.1 mol / L anhydrous ethanol solution of benzophenone; 10 vol% aqueous solution of acrylic acid; UV irradiation time 10 min.

[0047] Foaming raw materials (parts by weight): 100 parts of polyether polyol (hydroxyl value 56), 80 parts of MDI (NCO content 30%), 0.5 parts of water, 0.2 parts of amine catalyst A33, 0.1 parts of organotin catalyst T-9, 0.5 parts of diethanolamine, and 0.3 parts of silicone oil.

[0048] Upper rigid layer and lower rigid layer: rigid PVC sheet, 0.5 mm thick.

[0049] Epoxy resin film: 0.1 mm thick.

[0050] 2. Preparation steps (1) A circular through hole was opened at the center line of each side wall of the PP honeycomb using an ultraviolet laser drilling machine (wavelength 355 nm, power 10 W, frequency 40 kHz), and nitrogen was used for purging.

[0051] (2) After opening the honeycomb, clean it with acetone, anhydrous ethanol and deionized water in sequence for 10 min each, and then vacuum dry it at 50℃ for 2 h.

[0052] (3) Immerse the honeycomb in 0.1 mol / L benzophenone / ethanol solution for 1 h, then remove and dry in the dark and ventilated place for 20 min.

[0053] (4) Immerse the honeycomb in a 10 vol% acrylic acid aqueous solution, cover it with a quartz glass plate, and irradiate it in a UV curing chamber (wavelength 365 nm, power 100 W, distance 5 cm, time 10 min), with nitrogen gas purging throughout. After irradiation, ultrasonically clean it three times with acetone and vacuum dry it at 50 °C.

[0054] (5) Add the short carbon fibers to the polyether polyol and disperse them at high speed (1500 rpm, 10 min). Then add water, catalyst, crosslinking agent and silicone oil and mix evenly. Finally add MDI and stir quickly (1500 rpm, 10 s).

[0055] (6) Place the honeycomb in a vacuum injection mold, evacuate to -0.090 MPa, and maintain for 5 min. Inject the foaming material from the bottom of the mold, and apply ultrasonic vibration during the injection process (frequency 20 kHz, power 100 W, time 2 min). After injection, turn off the vacuum and restore normal pressure.

[0056] (7) Heat to 70℃ and allow to foam and cure for 10 min. Apply 0.5 MPa pressure 10 min after foaming begins and hold for 5 min.

[0057] (8) After demolding, the core layer is cured at 50°C for 2 hours to obtain the composite core layer.

[0058] (9) Place an epoxy resin film on the upper and lower surfaces of the core layer, and then place a rigid PVC sheet on top. Place it in a hot press at 100°C and 1.0 MPa for 40 seconds. After cooling, trim and trim the edges to obtain the finished flooring.

[0059] Example 2

[0060] 1. Materials and Parameters Honeycomb skeleton: PP honeycomb, height 15 mm, cell diameter 9 mm, wall thickness 0.35 mm, size 300 mm × 300 mm.

[0061] Horizontal through holes: Ultraviolet laser drilling, diameter 1.5 mm, horizontal spacing 7.5 mm.

[0062] Reinforcing material: Short-cut carbon fiber (T700 grade), 5 mm in length, 7 μm in diameter, 1.25 wt% added.

[0063] UV grafting: benzophenone concentration 0.2 mol / L; acrylic acid concentration 20 vol%; irradiation time 20 min.

[0064] Foaming raw materials: 100 parts polyether polyol, 85 parts MDI, 0.75 parts water, 0.35 parts A33, 0.2 parts T-9, 1.25 parts diethanolamine, and 0.65 parts silicone oil.

[0065] Rigid layer: TPU sheet, 1.0 mm thick.

[0066] Adhesive film: Epoxy resin adhesive film, 0.1 mm thick.

[0067] 2. Preparation steps (1) Laser drilling parameters: wavelength 355 nm, power 15 W, frequency 60 kHz, scanning speed 200 mm / s.

[0068] (2) Cleaning and drying are the same as in Example 1.

[0069] (3) Ultraviolet grafting: BP concentration 0.2 mol / L, soaking for 1.5 h, drying for 30 min; AA concentration 20 vol%, irradiation time 20 min (power 150 W, distance 8 cm), nitrogen protection.

[0070] (4) Reinforcing material dispersion: Short-cut carbon fibers are added to polyol and dispersed at high speed (2000 rpm, 15 min).

[0071] (5) Mixing of foaming materials: Same as in Example 1, but at a speed of 2000 rpm and a time of 10 s.

[0072] (6) Vacuum perfusion: vacuum degree -0.095 MPa, maintained for 8 min; ultrasonic vibration frequency 40 kHz, power 200 W, time 2 min.

[0073] (7) Curing: Heat to 80℃ and cure for 20 min; apply 1.0 MPa pressure 15 min after foaming begins and hold for 5 min.

[0074] (8) Post-curing: 50℃, 3 h.

[0075] (9) Hot pressing composite: temperature 110℃, pressure 1.25 MPa, pressure holding 50 s.

[0076] Example 3

[0077] 1. Materials and Parameters Honeycomb skeleton: PP honeycomb, height 20 mm, cell diameter 10 mm, wall thickness 0.5 mm, size 300 mm × 300 mm.

[0078] Horizontal through holes: Ultraviolet laser drilling, diameter 2.0 mm, horizontal spacing 10 mm.

[0079] Reinforcing material: Short-cut carbon fiber (T800 grade), 6 mm in length, 8 μm in diameter, 2.0 wt% added.

[0080] UV grafting: benzophenone concentration 0.3 mol / L; acrylic acid concentration 30 vol%; irradiation time 30 min.

[0081] Foaming raw materials: 100 parts polyether polyol, 90 parts MDI, 1.0 part water, 0.5 parts A33, 0.3 parts T-9, 2.0 parts diethanolamine, and 1.0 part silicone oil.

[0082] Rigid layer: TPU sheet, 2.0 mm thick.

[0083] Adhesive film: Epoxy resin adhesive film, 0.1 mm thick.

[0084] 2. Preparation steps (1) Laser drilling parameters: wavelength 355 nm, power 25 W, frequency 100 kHz, scanning speed 400 mm / s.

[0085] (2) Cleaning and drying are the same as in Example 1.

[0086] (3) Ultraviolet grafting: BP concentration 0.3 mol / L, soaking for 2 h, drying for 40 min; AA concentration 30 vol%, irradiation time 30 min (power 200 W, distance 10 cm), nitrogen protection.

[0087] (4) Enhanced material dispersion: high-speed dispersion (3000 rpm, 20 min).

[0088] (5) Mixing of foaming materials: 3000 rpm for 15 s.

[0089] (6) Vacuum perfusion: vacuum degree -0.098 MPa, maintained for 10 min; ultrasonic vibration frequency 40 kHz, power 300 W, time 5 min.

[0090] (7) Curing: Heat to 90℃ and cure for 30 min; apply 1.5 MPa pressure 20 min after foaming begins and hold for 10 min.

[0091] (8) Post-curing: 60℃, 4 h.

[0092] (9) Hot pressing composite: temperature 120℃, pressure 1.5 MPa, pressure holding 60 s.

[0093] Example 4

[0094] Difference: After cleaning and opening the honeycomb skeleton, UV-induced graft polymerization modification is not performed (step 7 of claim is omitted), otherwise it is the same as in Example 2.

[0095] Comparative Example 1 Difference: The honeycomb skeleton does not have any transverse through holes, and no short-cut carbon fibers are added to the foaming material (the amount added is 0). Everything else is the same as in Example 2.

[0096] Performance Testing: Peel strength, failure mode, and ball rebound rate were tested for Examples 1-4 and Comparative Example 1. Peel strength and failure mode were determined according to ASTM D1876-08 (Standard Test Method for Peel Resistance of Adhesives, T-type peel test). Ball rebound rate was determined according to EN 12235:2013 (Surfaces for sports areas—Determination of ball rebound). A complete finished flooring unit (at least 300 mm × 300 mm) was used as a sample, laid flat on a level, hard substrate surface (such as a concrete slab). No adhesive was applied between the sample and the substrate; stability was maintained solely by its own weight. At least three samples were tested for each example or comparative example. Test results are shown in Table 1.

[0097]

[0098] As shown in Table 1, Examples 1-4 all meet the requirements of EN 14904 for professional sports flooring (ball rebound rate ≥90%, impact absorption ≥53%). Among them, Example 2 has the best overall performance, while Example 4 is relatively worse. Comparative Example 1, due to the lack of transverse through-holes and the absence of a three-dimensional network, has a ball rebound rate of only 75.6%, which does not meet the standard.

[0099] Obviously, those skilled in the art can make various modifications and variations to this invention without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this invention and their equivalents, this invention also intends to include these modifications and variations.

Claims

1. A high-resilience, shock-absorbing floor, characterized in that, The structure comprises an upper rigid layer, a composite core layer, and a lower rigid layer arranged sequentially from top to bottom. The composite core layer includes a honeycomb skeleton, a reinforcing material, and a foam filler. One or more transverse through-holes penetrating the wall are provided on the sidewalls of the honeycomb lattice of the honeycomb skeleton. The reinforcing material is filled in the transverse through-holes. The foam filler is filled in the lattice of the honeycomb skeleton and the transverse through-holes, and encapsulates the reinforcing material therein. The reinforcing material and the foam filler are integrally cured to form a three-dimensional network structure.

2. The high-resilience shock-absorbing floor according to claim 1, characterized in that, The height of the honeycomb skeleton is 10-20 mm, the pore diameter is 8-10 mm, and the wall thickness is 0.2-0.5 mm; the transverse through holes are arranged at intervals in the horizontal direction with a spacing of 5-10 mm and a diameter of 1-2 mm.

3. The high-resilience shock-absorbing floor according to claim 1, characterized in that, The amount of the reinforcing material added accounts for 0.5-2.0 wt% of the total weight of the foaming raw material.

4. The high-resilience shock-absorbing floor according to claim 1, characterized in that, The honeycomb skeleton material is polypropylene or UV-induced grafted polymerized modified polypropylene; the reinforcing material is chopped fiber composite resin material or thermoplastic polyurethane elastomer; the foam filler is polyurethane foam material; the upper rigid layer and the lower rigid layer are each independently selected from rigid polyvinyl chloride sheet or thermoplastic polyurethane sheet.

5. A method for preparing a high-resilience, shock-absorbing floor according to any one of claims 1-4, characterized in that, Includes the following steps: A honeycomb skeleton is provided, and transverse through holes are opened on the wall surface of the honeycomb lattice of the honeycomb skeleton; reinforcing material is implanted into the transverse through holes, and foaming material is filled into the honeycomb lattice and transverse through holes, or the reinforcing material is dispersed in the foaming material and filled together with the foaming material; the foaming material is foamed and cured to form a foamed filler, and a composite core layer is obtained. The upper hard layer and the lower hard layer are respectively laminated onto the upper and lower surfaces of the composite core layer.

6. The preparation method according to claim 5, characterized in that, The transverse through hole is created using laser drilling or mechanical punching.

7. The preparation method according to claim 5, characterized in that, After creating the transverse through hole, the following steps are also included: Immerse the honeycomb skeleton in a 0.1-0.3 mol / L benzophenone / anhydrous ethanol solution for 1-2 hours, then remove and dry for 20-40 minutes. The dried honeycomb skeleton was immersed in an acrylic acid solution with a concentration of 10-30 vol%, and graft polymerization was carried out under ultraviolet light irradiation at a wavelength of 365 nm and a power of 100-200 W for 10-30 min. The ultraviolet light irradiation was carried out in a nitrogen atmosphere.

8. The preparation method according to claim 5, characterized in that, The foaming material is filled into the honeycomb pores and transverse through holes using a vacuum-assisted injection method. The vacuum degree of the vacuum-assisted injection method is -0.09 to -0.098 MPa. During the injection process, ultrasonic vibration is applied to assist in venting, with an ultrasonic frequency of 20–40 kHz.

9. The preparation method according to claim 5, characterized in that, Apply a pressure of 0.5–1.5 MPa 10–20 minutes after the start of foaming and curing, and hold the pressure for 5–10 minutes.

10. The preparation method according to claim 5, characterized in that, The steps of bonding the upper hard layer and the lower hard layer to the upper and lower surfaces of the composite core layer, respectively, include: An epoxy resin film is placed on the upper and lower surfaces of the composite core layer, followed by an upper and lower rigid layer. The core is then placed in a hot press and held at 100-120℃ and 1.0-1.5 MPa for 40-60 seconds.

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