New energy automobile interior damping polyurethane material and preparation method thereof

Abstract

The invention provides a new energy automobile interior damping polyurethane material and a preparation method thereof.The preparation method comprises the steps that an active polymer modifier and a polyalcohol matrix are mixed to obtain a modified polyalcohol solution, and the active polymer modifier comprises at least one of silane groups, thiol groups and fluorine-containing groups; adding a nano shock-resistant filler into the modified polyol solution, uniformly mixing, and slowly adding modified isocyanate to obtain a pre-polymerized solution; a reversible temperature-sensitive phase-change material is added into the pre-polymerized solution and stirred, then the mixture is placed in a mold, the mixture is cured and then cooled, the new energy automobile interior damping polyurethane material is obtained, and the phase-change temperature of the reversible temperature-sensitive phase-change material is 30-40 DEG C. Therefore, the damping buffering and energy dissipation capabilities are improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of new energy vehicle materials, and in particular relates to a new energy vehicle interior shock-absorbing polyurethane material and a preparation method thereof. Background Art

[0002] Traditional automotive interiors typically utilize materials such as genuine leather, synthetic leather, PVC, fabrics, injection-molded plastics, and traditional polyurethane foam. These materials offer excellent aesthetics, wear resistance, and cost-effectiveness, but they have limitations in vibration damping and sound insulation. For example, traditional high-end vehicles often use natural leather for seats, door panels, instrument panels, and other decorative materials. While it offers a pleasant tactile feel and a luxurious feel, genuine leather itself has limited elasticity and energy absorption properties. Its primary advantages lie in aesthetics and comfort, but it lacks high kinetic energy damping capacity. Due to cost and maintenance factors, many mid-range and low-end vehicles opt for synthetic leather, which is typically made from PVC or PU that has been coated and embossed. While synthetic leather is lighter and more wear-resistant than genuine leather, its inherent density and hardness make it less effective at absorbing vibrations and dissipating energy. Polyurethane foam is used in seats, headrests, and interior padding. Traditional polyurethane foam primarily provides comfortable cushioning through its open or closed-cell structure, but its design often focuses on comfort and support rather than optimizing vibration energy absorption. Their microstructures are often not finely tuned and lack energy dissipation designs for high-frequency impacts or continuous vibrations. As a result, their shock-absorbing capabilities are insufficient when the car is traveling at high speeds or encounters road impacts.

[0003] In particular, since new energy vehicles typically use electric drive systems and have low engine noise, other noise (such as road and wind noise) and vibration inside the vehicle become more prominent in affecting ride comfort. Therefore, the shock absorption, cushioning, and energy dissipation capabilities of traditional interior materials are clearly insufficient. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a shock-absorbing polyurethane material for the interior of new energy vehicles and a preparation method thereof, aiming to solve the problem of insufficient shock absorption, buffering and energy dissipation capacity of the interior material.

[0005] To solve the above problems, the present invention proposes a method for preparing a shock-absorbing polyurethane material for new energy vehicle interior, comprising the following steps: S1. Mixing an active polymer modifier with a polyol matrix to obtain a modified polyol solution, wherein the active polymer modifier comprises at least one of a silane group, a thiol group, and a fluorine-containing group; S2, adding a nano-vibration-damping filler to the modified polyol solution, mixing well, and then slowly adding a modified isocyanate to obtain a prepolymer solution; S3. Add a reversible temperature-sensitive phase change material to the prepolymer solution and stir the mixture, then place the mixture in a mold, solidify the mixture, and cool the mixture to obtain a new energy vehicle interior shock-absorbing polyurethane material, wherein the phase change temperature of the reversible temperature-sensitive phase change material is 30-40°C.

[0006] In some embodiments of the present invention, in step S1, the active polymer modifier includes at least one of silane functional polyacrylate, thiol functional polyethyleneimine, and fluorinated modified polyurethane prepolymer, and the polyol matrix includes at least one of polyether polyol, polyester polyol, and epoxy polyol.

[0007] In some embodiments of the present invention, the ratio of the active polymer modifier to the polyol matrix is ​​1:(10-50) calculated by mass.

[0008] In some embodiments of the present invention, step S1 includes: S1.1. Pour the polyol matrix into the reactor and add the active polymer modifier. Stir at room temperature for 10-15 minutes at a stirring speed of 300-500 rpm. S1.2. Increase the speed to 2000-3000 rpm and stir for 5-10 minutes. After stirring, obtain a modified polyol solution. Place the modified polyol solution in an ultrasonic homogenizer and treat with ultrasound for 5-10 minutes until the viscosity of the modified polyol solution is 800-1500 mPa·s.

[0009] In some embodiments of the present invention, in step S2, the nano-vibration-damping filler includes at least one of silane-modified nano-silica gel, surface functionalized nano-montmorillonite, and nano-modified alumina particles, the particle size of the nano-vibration-damping filler is 10~80nm, and the modified isocyanate includes at least one of silane-modified isocyanate, fluorinated isocyanate, and thiol-modified isocyanate.

[0010] In some embodiments of the present invention, calculated by mass ratio, the modified polyol solution: the nano-vibration-damping filler: the modified isocyanate = (6-8): (1-2): (1-2).

[0011] In some embodiments of the present invention, step S2 includes: S2.1. Slowly add the nano-vibration-damping filler to the modified polyol solution, set the stirring rate to 2000-3000 rpm, and control the mixing time to 5-10 minutes; S2.2. Add modified isocyanate dropwise, adjust the rotation speed to 300-500 rpm, control the addition time within 10-15 minutes, and maintain the reaction temperature at 25-30°C to obtain a prepolymer solution.

[0012] In some embodiments of the present invention, step S3 includes: S3.1. Heat the phase change material to a liquid state at 45-50°C, add the coating material solution, and emulsify the mixture while stirring at 1500-2000 rpm. Slowly add the crosslinking agent dropwise and allow the reaction to proceed for 30-60 minutes. Filter and wash the mixture to obtain the reversible temperature-sensitive phase change material. S3.2, add the reversible thermosensitive phase change material to the prepolymer solution, adjust the speed to 300~500rpm, control the temperature at 25~30℃, stir for 10 minutes, and then let it stand for 1~2 hours; S3.3. Raise the temperature to 60°C, cure for 2 hours, and cool to obtain the shock-absorbing polyurethane material for new energy vehicle interior.

[0013] In some embodiments of the present invention, in step S3, calculated by mass ratio, the reversible temperature-sensitive phase change material: the prepolymer solution = (1~2): (8~9), the phase change material includes at least one of a paraffin-type material, a fatty acid mixture, and a liquid crystal phase change polymer, the coating material solution includes at least one of polymethyl methacrylate, polyvinyl alcohol, and a polyurethane prepolymer, and the cross-linking agent includes at least one of a diisocyanate cross-linking agent, a cross-linked acrylic monomer, and N,N'-methylenebisacrylamide. Calculated by mass ratio, the core phase change material: the coating material solution: the cross-linking agent = (70~90): (10~30): (5~10).

[0014] The present invention provides a new energy vehicle interior shock-absorbing polyurethane material, which is prepared by the above-mentioned preparation method of the new energy vehicle interior shock-absorbing polyurethane material. The new energy vehicle interior shock-absorbing polyurethane material comprises an active polymer modifier, a polyol matrix, a nano-shock-absorbing filler and a reversible temperature-sensitive phase change material; wherein, The active polymer modifier is used to improve the reactivity and interfacial bonding strength of the polyol matrix; The polyol matrix is ​​used to form the polyurethane main chain; The nano shock-absorbing filler is used to disperse and absorb mechanical impact energy; The reversible temperature-sensitive phase change material is used to absorb or release thermal energy.

[0015] Compared with the prior art, the preparation method of a shock-absorbing polyurethane material for new energy vehicle interior in the present invention has the following beneficial effects: Nano-vibration-damping fillers form a microscopic skeleton within the polyurethane network, dispersing stress and absorbing impact energy. This allows the material to effectively attenuate energy when subjected to vibration or impact, reducing noise and vibration transmission. The reversible temperature-sensitive phase-change material undergoes a phase transition between 30°C and 40°C, absorbing heat as the interior temperature rises and releasing it as it drops, enabling adaptive temperature control and further improving ride comfort.

[0016] Therefore, the shock-absorbing polyurethane material used in new energy vehicle interiors automatically adjusts its local rigidity and cushioning properties based on actual temperature fluctuations within the vehicle. At high temperatures, it absorbs excess energy through phase change, reducing peak interior surface temperatures. At low temperatures, it releases this stored heat, preventing the material from hardening and ensuring comfort. The addition of an active polymer modifier improves the interfacial compatibility between the polyol matrix and the filler, resulting in a more uniform polyurethane network structure and stronger crosslinking, thereby enhancing overall mechanical and shock-absorbing properties. This structure helps extend the material's service life and reduces aging and cracking caused by long-term vibration or temperature cycling. The use of a modified polyurethane system reduces the use of harmful chemicals in traditional interior materials and enables a lighter structure, contributing to the overall lightweighting and energy efficiency of new energy vehicles. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 The present invention is a schematic flow chart of a method for preparing a shock-absorbing polyurethane material for interior decoration of new energy vehicles in one embodiment of the present invention. DETAILED DESCRIPTION

[0018] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0019] Please refer to Figure 1 A method for preparing a shock-absorbing polyurethane material for interior decoration of new energy vehicles, comprising the following steps: S1. Mixing an active polymer modifier with a polyol matrix to obtain a modified polyol solution, wherein the active polymer modifier includes at least one of a silane group, a thiol group, and a fluorine-containing group.

[0020] In step S1, the active polymer modifier includes at least one of a silane-functionalized polyacrylate, a thiol-functionalized polyethyleneimine, and a fluorinated modified polyurethane prepolymer, and the polyol matrix includes at least one of a polyether polyol, a polyester polyol, and an epoxy polyol. The weight ratio of active polymer modifier to polyol matrix is ​​1:(10-50).

[0021] Silane-functional polyacrylates contain acrylic chains and silane groups, which can partially hydrolyze in polyols to form silanols, which can then undergo condensation reactions with polyols or subsequent isocyanates. Thiol-functionalized polyethyleneimine molecules contain –SH groups, which can undergo thiol-ene click reactions or form partial disulfide bonds with difunctional isocyanates or other reactive components in subsequent reactions, facilitating dynamic crosslinking and stress relaxation. Fluorinated polyurethane prepolymers containing fluorinated groups can reduce the surface energy of the system, improving oil resistance and interfacial compatibility.

[0022] Step S1 includes: S1.1. Pour the polyol matrix into the reactor and add the active polymer modifier at the same time. Stir at room temperature for 10-15 minutes at a stirring speed of 300-500 rpm.

[0023] Under low-speed stirring, the polyol matrix, due to its low viscosity, gently disperses the reactive polymer modifier into the liquid phase. For silane-functionalized polyacrylates, whose silane groups are stable at room temperature, initial stirring facilitates dispersion without causing premature hydrolysis. For thiol-functionalized polyethyleneimine and fluorinated polyurethane prepolymers, low-speed stirring prevents high shear forces that can lead to chain breakage or structural damage. Low-speed stirring reduces air incorporation, ensuring a clear air bubble in the reactor, and providing an excellent foundation for subsequent high-shear homogenization and precise viscosity control. Initial mixing ensures full contact between the polyol matrix and the reactive polymer modifier, forming an initial physical bond through hydrogen bonding and van der Waals forces between the functional groups (silane, thiol, fluorine) in the modifier and the polyol molecules, improving interfacial compatibility and providing a uniform foundation for subsequent chemical reactions.

[0024] S1.2. Increase the speed to 2000-3000 rpm and stir for 5-10 minutes. After stirring, obtain a modified polyol solution. Place the modified polyol solution in an ultrasonic homogenizer and treat with ultrasound for 5-10 minutes until the viscosity of the modified polyol solution is 800-1500 mPa·s.

[0025] High-speed stirring provides sufficient shear force to completely break up the microaggregates formed in the S1.1 stage, achieving uniform dispersion at the molecular level. At this point, the silane groups can be evenly distributed throughout the polyol matrix, creating a uniform interface for subsequent hydrolysis and condensation reactions. Thiol groups are also more easily exposed under high-speed shear, and their functionality facilitates subsequent rapid reaction with isocyanates to form a dynamic cross-linked structure. Fluoro groups, due to their low surface energy, can be more evenly dispersed during high-speed stirring, resulting in excellent interfacial lubrication and contamination resistance.

[0026] Ultrasonic waves create microcavitation in the solution, destroying residual bubbles and microaggregates, thereby further refining the dispersed particle size. Ultrasonic treatment allows for more precise viscosity control, ultimately reaching the target range of 800–1500 mPa·s, providing ideal rheological conditions for subsequent isocyanate reaction and foaming. In the homogenized solution, the active polymer modifier and polyol matrix molecules are evenly distributed, resulting in highly reactive functional groups. This uniform dispersion promotes uniform crosslinking between the components during the subsequent polyurethane formation process, forming a dense polyurethane network with excellent mechanical properties.

[0027] The uniform distribution of the silane, thiol, and fluorine groups in the modifier during homogenization facilitates rapid chemical bonding during the subsequent reaction with isocyanate, thereby increasing the crosslink density and overall stability of the polyurethane network. A viscosity of 800-1500 mPa·s not only facilitates subsequent mixing and casting, but also provides a balanced control of reaction kinetics, preventing runaway reactions or structural defects caused by excessively high or low viscosities. The homogenized modified polyol solution ensures that the subsequent addition of the nano-vibration-damping filler, modified isocyanate, and reversible temperature-sensitive phase change material allows for full contact and synergistic interaction, ultimately improving the comprehensive performance of the shock-absorbing polyurethane material for new energy vehicle interiors in terms of vibration reduction, energy dissipation, and temperature adaptability.

[0028] S2. Add a nano-vibration-damping filler to the modified polyol solution, mix thoroughly, and then slowly add a modified isocyanate to obtain a prepolymer solution. In step S2, the nano-vibration-damping filler includes at least one of silane-modified nano-silica gel, surface-functionalized nano-montmorillonite, and nano-modified alumina particles. The particle size of the nano-vibration-damping filler is 10-80 nm. The modified isocyanate includes at least one of silane-modified isocyanate, fluorinated isocyanate, and thiol-modified isocyanate. The mass ratio of modified polyol solution: nano-vibration-damping filler: modified isocyanate is (6-8): (1-2): (1-2).

[0029] The surface of silane-modified nano-silica gel is coated with silane groups, which helps to form chemical or hydrogen bonds with the polyol matrix; the surface-functionalized nano-montmorillonite is organically modified to expand its interlayer spacing and enhance its dispersibility; the surface of nano-modified alumina particles is treated with a coupling agent to improve its compatibility with the organic matrix.

[0030] Silane-modified isocyanate introduces silane groups to improve the chemical compatibility with the interface of polyol and nanofiller; the fluorine-containing groups in fluorinated isocyanate help improve weather resistance and low-energy surface properties, thereby enhancing the overall material's stain and oil resistance; the thiol-containing groups in thiol-modified isocyanate can react with active groups under appropriate conditions to form a dynamic cross-linking structure, which is conducive to self-repair and stress relaxation.

[0031] Step S2 includes: S2.1. Slowly add the nano-vibration-damping filler into the modified polyol solution, set the stirring rate to 2000-3000 rpm, and control the mixing time to 5-10 minutes.

[0032] High-speed shear stirring provides sufficient mechanical shear force to evenly disperse the nanoparticles in the modified polyol solution, breaking down any possible agglomeration. This ensures molecular-level uniform dispersion of the nano-vibration-damping filler within the polyol matrix. The uniformly dispersed nanoparticles help form a continuous microstructure, providing localized stress dispersion and energy dissipation channels within the subsequent polyurethane cross-linked network, significantly enhancing the material's vibration damping and energy absorption properties. Surface modification of the nanofillers with silane, hydroxyl, or other functional groups allows for hydrogen bonding or weak chemical bonding with polar groups in the polyol molecules. This enhanced interfacial interaction between the filler and the matrix helps securely anchor the filler within the polyurethane network, preventing filler dislocation or agglomeration, thereby ensuring mechanical uniformity and sustained vibration damping performance. The nanoparticles dispersed within the matrix form a microstructure that, when subjected to external shock or vibration, absorbs some of the mechanical energy through interparticle friction and slippage. This improves the material's energy dissipation capacity under high-frequency vibration and impact loads, thereby enhancing vibration damping performance.

[0033] S2.2. Add modified isocyanate dropwise, adjust the rotation speed to 300-500 rpm, control the addition time within 10-15 minutes, and maintain the reaction temperature at 25-30°C to obtain a prepolymer solution.

[0034] Low-speed stirring allows the modified isocyanate to be added slowly and evenly, ensuring full contact with the hydroxyl groups in the modified polyol solution. During this process, a polymerization reaction occurs between the polyol and the isocyanate, forming a prepolymer. Low-speed stirring prevents localized overconcentration and violent reactions, ensuring a uniform structure in the resulting prepolymer solution. Furthermore, the reaction temperature is well controlled to avoid uneven distribution or side reactions caused by excessively high temperatures. The specialized functional groups (silane, fluorine, or thiol) in the modified isocyanate chemically bond or physically interact with the functional groups on the polyol matrix and the surface of the nano-vibration-damping filler. This synergistic effect helps firmly embed the nano-vibration-damping filler into the cross-linked network during polyurethane formation, while also forming a denser interfacial structure, thereby optimizing the overall mechanical properties and vibration damping effectiveness of the material. During the dropwise addition of the modified isocyanate, the temperature and stirring rate are controlled to ensure that the prepolymer solution achieves optimal fluidity and equilibrium viscosity. Controlling the viscosity and fluidity of the prepolymer solution directly impacts the uniformity of the subsequent casting, foaming, and curing processes, as well as the microstructure of the final product. The ideal rheological state helps to form a uniform and dense polyurethane network, thereby ensuring the excellent performance of the final product in terms of shock absorption, energy absorption, etc.

[0035] S2.1 uses high-speed stirring and ultrasound to achieve uniform nanoscale dispersion of the nano-vibration-damping filler in the modified polyol solution, forming a microscopic skeleton that effectively disperses stress and absorbs energy. S2.2 uses low-speed dropwise addition of the modified isocyanate to ensure a uniform reaction between the polyol and the isocyanate, promoting the homogeneous formation of the prepolymer. Functional modification also enhances the interfacial chemical interactions between the components.

[0036] The silane, fluorine, and thiol groups in the modified isocyanate chemically bond with the corresponding functional groups on the polyol matrix and the nanofiller surface, respectively, forming a stable interfacial bond. This design not only ensures the stability of the prepolymer solution but also lays a solid foundation for subsequent polyurethane network construction. Controlling the addition and reaction temperature within the 25-30°C range not only avoids localized unevenness caused by overheating, but also ensures a moderate viscosity for the prepolymer solution, providing ideal conditions for subsequent casting and curing.

[0037] This step leverages the advantages of nanofillers in forming a multi-level energy dissipation network within the polyurethane system while simultaneously enhancing interfacial compatibility through the specialized functionality of modified isocyanates, thereby enabling the coordinated construction of a multi-level structure from the molecular to the nanoscale. This process, building upon traditional polyurethane prepolymer preparation by further incorporating functional fillers and interfacial modification, demonstrates significant innovation and potential for engineering applications.

[0038] S3. Add the reversible temperature-sensitive phase change material to the prepolymer solution, stir, place in a mold, solidify, and cool to obtain a new energy vehicle interior shock-absorbing polyurethane material. The reversible temperature-sensitive phase change material has a phase transition temperature of 30-40°C. The mass ratio of reversible temperature-sensitive phase change material to prepolymer solution is (1-2): (8-9).

[0039] Step S3 includes: S3.1. Heat the phase change material to a liquid state, control the temperature at 45-50°C, add the coating material solution, emulsify at a stirring speed of 1500-2000 rpm, slowly add the cross-linking agent dropwise, react for 30-60 minutes, filter and wash to obtain a reversible temperature-sensitive phase change material.

[0040] The phase change material includes at least one of a paraffin-type material, a fatty acid mixture, and a liquid crystal phase change polymer; the coating material solution includes at least one of polymethyl methacrylate, polyvinyl alcohol, and a polyurethane prepolymer; the cross-linking agent includes at least one of a diisocyanate cross-linking agent, a cross-linking acrylic monomer, and N,N'-methylenebisacrylamide. Calculated by mass ratio, the core phase change material: coating material solution: cross-linking agent = (70~90): (10~30): (5~10).

[0041] Paraffin-based materials have a high latent heat absorption capacity; fatty acid mixtures can precisely adjust the phase transition temperature by controlling the mixing ratio; liquid crystal phase change polymers undergo an ordered change in arrangement at a specific temperature, achieving a rapid thermal response. Polymethyl methacrylate forms a hard, transparent coating; polyvinyl alcohol provides good water solubility and flexibility; and polyurethane prepolymers offer good compatibility with subsequent polyurethane systems. Crosslinkers, through crosslinking reactions (such as free radical polymerization of isocyanates with hydroxyl or acrylic monomers), rapidly solidify the coating on the droplet surface, forming a dense protective layer.

[0042] By emulsifying in a liquefied state, the reversible thermosensitive phase change material can be dispersed into tiny droplets. High-shear stirring provides sufficient shear force to make the droplet size uniform, which is conducive to subsequent cross-linking and curing to form uniform microcapsules. The cross-linking agent is slowly added dropwise to allow the coating material to gradually cross-link and cure on the surface of the droplets, forming a dense and flexible polymer shell that protects the core material from the external environment while ensuring that it is not easily broken during the subsequent mixing and curing process. The resulting reversible thermosensitive phase change material has a stable phase transition temperature (30-40°C). It can absorb or release heat when the phase transition temperature is reached and return to its original state when the temperature drops, achieving reversibility and providing temperature adaptive control capabilities for the subsequent interior shock absorption function.

[0043] S3.2. Add reversible temperature-sensitive phase change material to the prepolymer solution, adjust the rotation speed to 300-500 rpm, control the temperature at 25-30°C, stir for 10 minutes, and then let it stand for 1-2 hours.

[0044] The polyurethane backbone and cross-linked matrix offer low viscosity, facilitating subsequent uniform dispersion. As a thermosensitive energy absorption unit, its surface coating exhibits excellent compatibility with the polyol and modified isocyanate prepolymer in the prepolymer solution, allowing for uniform embedding within the polyurethane network after curing. Operating at 25-30°C prevents premature phase change of the RTPCM coating while ensuring fluidity and mixing of the prepolymer solution. Low-speed stirring ensures uniform dispersion of the RTPCM within the prepolymer solution, preventing aggregation and sedimentation, and ensuring uniform distribution during subsequent curing. A favorable interface is formed between the prepolymer solution and the RTPCM, allowing the RTPCM to be firmly embedded within the polyurethane matrix through physical interactions and potential chemical bonding (such as hydrogen bonding or coupling agent interactions). Allowing the system to rest for 1-2 hours further stabilizes the dispersion, reduces internal stress, and lays a foundation for uniform curing during subsequent molding.

[0045] S3.3. Raise the temperature to 60°C, cure for 2 hours, and cool to obtain the shock-absorbing polyurethane material for new energy vehicle interior.

[0046] During the curing phase, the polyurethane backbone is fully cross-linked at 60°C, forming a robust three-dimensional network that secures the pre-mixed nano-damping filler and RTPCM. Precise temperature control during the curing process ensures the RTPCM coating remains intact, preserving its reversible phase-change properties. After cooling, the RTPCM can absorb and release heat within a range of 30-40°C, providing adaptive temperature control for the interior. The resulting polyurethane network, combined with the embedded nano-damping filler and RTPCM, creates a multi-stage energy dissipation structure. When subjected to vibration or impact, the nano-damping filler disperses stress, the RTPCM absorbs heat, and the localized stiffness modulation achieves excellent shock absorption, enhancing the cushioning and comfort of new energy vehicle interiors.

[0047] In one embodiment, a sample of appropriate size (e.g., a 50 × 50 × 10 mm block) is cut from the prepared new energy vehicle interior shock-absorbing polyurethane material, ensuring that the sample surface is flat and free of obvious mechanical damage. The sample is then secured on a dedicated testing platform to prevent movement during testing and to avoid external interference.

[0048] Set up the microwave transmission and reception system, select a broadband frequency (e.g., 2–6 GHz) and an appropriate polarization mode (e.g., parallel polarization) to ensure that it can penetrate the material and has high resolution.

[0049] Adjust the scanning platform so that the transmitting antenna and the receiving antenna cover the entire surface of the sample, and scan according to the preset scanning path.

[0050] Start the microwave emission system to transmit continuous or pulsed microwave signals to the sample, and use the receiving antenna to collect the reflected or transmitted signals.

[0051] The amplitude and phase information of each scanning point in the preset scanning path are recorded to obtain a two-dimensional digital hologram data set.

[0052] Image reconstruction is performed based on the two-dimensional digital hologram data set to obtain a test pattern.

[0053] In one embodiment, to improve detection accuracy, multi-angle scanning and multi-frequency acquisition methods are used to collect scattered field data at different angles and frequencies, respectively, to provide sufficient information for subsequent reconstruction.

[0054] Correcting the scanned two-dimensional digital hologram dataset before image reconstruction can improve the accuracy of the test pattern. The correction equation for the two-dimensional digital hologram dataset is as follows: in, Is a cost function used to measure the current phase or amplitude correction distribution The quality of image reconstruction. The smaller the value, the smaller the difference from the reference distribution, and the closer the reconstructed image is to the ideal state. In phase correction or adaptive focusing algorithms, iterative adjustments are often required. , to minimize And get the best imaging quality. It is the complex amplitude distribution on the two-dimensional digital hologram data set, consisting of amplitude and phase. It is obtained by performing multi-angle and multi-frequency scanning of the sample through a microwave holographic imaging system, recording the amplitude and phase information of the echo signal, and then processing the data. The amplitude part can be normalized to [0, 1] or an integer pixel value between 0 and 255, and the phase part is between [-π, π], which represents the phase distribution of the wavefront at the pixel point. is the phase correction factor applied by Apply a phase compensation , to correct the phase distortion caused by various errors (such as optical path difference, system mismatch, etc.) in the two-dimensional digital hologram data set. In the adaptive focusing algorithm, It will be initialized to 0 or an estimated value and minimized during the iteration The guidelines are gradually updated. It can be changed in the range of [-π,π]. The amplitude is always 1, and the direction (phase) varies with Change, i is the imaginary unit, i is essentially , multiplying by i will increase the phase of the complex number by 90°, thereby realizing rotation. It is a pure phase rotation operation on the complex field, which is simple, direct, and does not change the amplitude of the signal, but only corrects the phase. is the reference distribution, which is the expected or target complex amplitude distribution. It can be understood as the reconstructed image under the "ideal state". It is a two-dimensional digital hologram dataset directly taken from some known standard samples. The amplitude can be in the range of [0, 1] or integer pixel values ​​from 0 to 255, and the phase is in the range of [-π, π]. ) represents the 2D pixel coordinates in the 2D digital hologram dataset. It is determined by the discrete sampling of the imaging system, which is determined by the position of the digital detector (such as array antenna, CCD / CMOS) or the scanning platform.

[0055] The sample is scanned at multiple angles or multiple frequencies using a microwave (or other wavelength) holographic imaging system to obtain complex holographic data containing amplitude and phase. When starting phase correction, Initialized to zero or small perturbation, It can be obtained by known standard samples. In each iteration, update so that Gradually decrease, when When the method converges to a threshold or the number of iterations reaches an upper limit, the optimal phase correction distribution is obtained. The convergence threshold can be 90% lower than the initial value. During the iteration process, when the values ​​of two adjacent iterations are When the change is less than the proportional threshold (such as 1%), the iteration stops. The number of iterations is between 20 and 200. Used for image reconstruction.

[0056] To reconstruct the image, a wave propagation model (such as the angular spectrum method or Fresnel diffraction) is used. Specifically, the corrected field is Fourier transformed (or convolved), then multiplied by a phase compensation factor based on the propagation distance. Finally, an inverse Fourier transform is performed back to the spatial domain to obtain a complex distribution in the plane. By taking the amplitude or phase of this distribution, the corresponding reconstructed image is obtained. The aforementioned models are well known to those skilled in the relevant art and will not be elaborated on here.

[0057] In one embodiment, the correction equation may also be: in, Used for amplitude correction, it can be initialized to 1 (no scaling) and continuously updated during iterations. is the original phase. In this way, both the amplitude and phase are directed toward The direction of the approach is close to that of the complex number, achieving complete complex matching. At this time, it is possible to correct the amplitude error caused by material characteristics and the phase mismatch caused by various optical path differences.

[0058] Test patterns can visually display the distribution of various components within the polyurethane material (such as nano-vibration damping fillers and reversible thermosensitive phase-change microcapsules), verifying whether the desired uniform dispersion is achieved during mixing, dispersion, and curing. Image reconstruction can detect defects within the material, such as bubbles, cracks, interlayer separation, filler agglomeration, or microcapsule breakage. These defects can affect the material's vibration damping performance and durability, and timely identification and location facilitate process adjustments. The quantitative and qualitative data provided by the test patterns can serve as feedback to guide adjustments to the preparation process (such as stirring rate, temperature control conditions, and curing time), thereby continuously improving product consistency and performance stability. Analysis of defects and structural uniformity in the images can indirectly predict the material's mechanical properties, vibration damping capacity, and energy dissipation, providing quality assurance for final product applications. Using microwave holographic nondestructive testing technology, internal information can be obtained without damaging the sample. This allows for real-time testing on the production line to ensure that each batch of product meets design requirements.

[0059] The present invention provides a new energy vehicle interior shock-absorbing polyurethane material, which is prepared by a new energy vehicle interior shock-absorbing polyurethane material preparation method. The new energy vehicle interior shock-absorbing polyurethane material comprises an active polymer modifier, a polyol matrix, a nano shock-absorbing filler and a reversible temperature-sensitive phase change material; wherein, Active polymer modifiers are used to improve the reactivity and interfacial bonding strength of the polyol matrix; The polyol matrix is ​​used to form the polyurethane backbone; Nano shock-absorbing fillers are used to disperse and absorb mechanical impact energy; Reversible temperature-sensitive phase change materials are used to absorb or release thermal energy.

[0060] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A method for preparing a shock-absorbing polyurethane material for new energy vehicle interior, characterized in that the steps include: S1. Mixing an active polymer modifier with a polyol matrix to obtain a modified polyol solution, wherein the active polymer modifier comprises at least one of a silane group, a thiol group, and a fluorine-containing group; S2, adding a nano-vibration-damping filler to the modified polyol solution, mixing well, and then slowly adding a modified isocyanate to obtain a prepolymer solution; S3. Add a reversible temperature-sensitive phase change material to the prepolymer solution and stir the mixture, then place the mixture in a mold, solidify the mixture, and cool the mixture to obtain a new energy vehicle interior shock-absorbing polyurethane material, wherein the phase change temperature of the reversible temperature-sensitive phase change material is 30-40°C.

2. The method for preparing a shock-absorbing polyurethane material for new energy vehicle interior according to claim 1, characterized in that: In step S1, the active polymer modifier includes at least one of silane functional polyacrylate, thiol functional polyethyleneimine, and fluorinated modified polyurethane prepolymer, and the polyol matrix includes at least one of polyether polyol, polyester polyol, and epoxy polyol.

3. The method for preparing a shock-absorbing polyurethane material for interior decoration of new energy vehicles according to claim 1 or 2, characterized in that: Calculated by mass ratio, the active polymer modifier: the polyol matrix = 1: (10~50).

4. The method for preparing a shock-absorbing polyurethane material for new energy vehicle interior according to claim 1, characterized in that: Step S1 includes: S1.

1. Pour the polyol matrix into the reactor and add the active polymer modifier. Stir at room temperature for 10-15 minutes at a stirring speed of 300-500 rpm. S1.

2. Increase the speed to 2000-3000 rpm and stir for 5-10 minutes. After stirring, obtain a modified polyol solution. Place the modified polyol solution in an ultrasonic homogenizer and treat with ultrasound for 5-10 minutes until the viscosity of the modified polyol solution is 800-1500 mPa·s.

5. The method for preparing a shock-absorbing polyurethane material for interior decoration of new energy vehicles according to claim 1, characterized in that: In step S2, the nano-vibration-damping filler includes at least one of silane-modified nano-silica gel, surface-functionalized nano-montmorillonite, and nano-modified alumina particles. The particle size of the nano-vibration-damping filler is 10~80nm, and the modified isocyanate includes at least one of silane-modified isocyanate, fluorinated isocyanate, and thiol-modified isocyanate.

6. The method for preparing a shock-absorbing polyurethane material for interior decoration of new energy vehicles according to claim 1 or 5, characterized in that: Calculated by mass ratio, the modified polyol solution: the nano-vibration-damping filler: the modified isocyanate = (6~8): (1~2): (1~2).

7. The method for preparing a shock-absorbing polyurethane material for interior decoration of new energy vehicles according to claim 1, characterized in that: Step S2 includes: S2.

1. Slowly add the nano-vibration-damping filler to the modified polyol solution, set the stirring rate to 2000-3000 rpm, and control the mixing time to 5-10 minutes; S2.

2. Add modified isocyanate dropwise, adjust the rotation speed to 300-500 rpm, control the addition time within 10-15 minutes, and maintain the reaction temperature at 25-30°C to obtain a prepolymer solution.

8. The method for preparing a shock-absorbing polyurethane material for new energy vehicle interior according to claim 1, characterized in that: Step S3 includes: S3.

1. Heat the phase change material to a liquid state at 45-50°C, add the coating material solution, and emulsify the mixture while stirring at 1500-2000 rpm. Slowly add the crosslinking agent dropwise and allow the reaction to proceed for 30-60 minutes. Filter and wash the mixture to obtain the reversible temperature-sensitive phase change material. S3.2, add the reversible thermosensitive phase change material to the prepolymer solution, adjust the speed to 300~500rpm, control the temperature at 25~30℃, stir for 10 minutes, and then let it stand for 1~2 hours; S3.

3. Raise the temperature to 60°C, cure for 2 hours, and cool to obtain the shock-absorbing polyurethane material for new energy vehicle interior.

9. The method for preparing a shock-absorbing polyurethane material for interior decoration of new energy vehicles according to claim 8, characterized in that: In step S3, according to the mass ratio, the reversible temperature-sensitive phase change material: the prepolymer solution = (1~2): (8~9), the phase change material includes at least one of a paraffin-type material, a fatty acid mixture, and a liquid crystal phase change polymer, the coating material solution includes at least one of polymethyl methacrylate, polyvinyl alcohol, and a polyurethane prepolymer, and the cross-linking agent includes at least one of a diisocyanate cross-linking agent, a cross-linked acrylic monomer, and N,N'-methylenebisacrylamide. According to the mass ratio, the core phase change material: the coating material solution: the cross-linking agent = (70~90): (10~30): (5~10).

10. A new energy vehicle interior shock-absorbing polyurethane material, characterized in that: The new energy vehicle interior shock-absorbing polyurethane material is prepared by the preparation method of any one of claims 1 to 9, wherein the new energy vehicle interior shock-absorbing polyurethane material comprises an active polymer modifier, a polyol matrix, a nano shock-absorbing filler and a reversible temperature-sensitive phase change material; wherein, The active polymer modifier is used to improve the reactivity and interfacial bonding strength of the polyol matrix; The polyol matrix is ​​used to form the polyurethane main chain; The nano shock-absorbing filler is used to disperse and absorb mechanical impact energy; The reversible temperature-sensitive phase change material is used to absorb or release thermal energy.

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