Shock-absorbing, heat-insulating and sound-absorbing TPU automobile seat cushion and preparation method thereof

Abstract

The invention belongs to the technical field of functional post-treatment of 3D printing polymer parts, and particularly relates to a shock-absorbing, heat-insulating and sound-absorbing TPU automobile seat cushion and a preparation method thereof. An integral TPU seat cushion with a hollow structure is formed by adopting a selective laser sintering (SLS) technology, an epoxy resin-based micro-foaming coating taking glass hollow microspheres as a physical foaming micropore source is prepared, the surface of a hollow lattice supporting body of a TPU seat cushion part is coated with the epoxy resin-based micro-foaming coating, and the coating formed through curing has a micro-foaming structure, so that the surface of the TPU seat cushion part is coated with the epoxy resin-based micro-foaming coating. And the heat insulation and sound absorption effects in the automobile running process are effectively improved. The micro-foaming coating also has toughening, heat-insulating and wear-resisting properties at the same time, and the coating infiltrating into the micro-gaps on the surface layer of the selective laser sintering TPU workpiece in the coating process forms an anchoring structure after being cured, so that the adhesive force of the coating to the TPU substrate is improved, and the service life of the automobile seat cushion is prolonged.

Description

Technical Field

[0001] The invention belongs to the technical field of functional post-processing of 3D printed polymer parts, and specifically relates to a shock-absorbing, heat-insulating, and sound-absorbing TPU automobile seat pad and a preparation method thereof. Background Art

[0002] Logistics, as an important part of economic development, is a complex service industry that integrates transportation, warehousing, freight forwarding, information and other industries. It is a basic and strategic industry that supports the development of the national economy. Large container trucks play a vital role in logistics and are a key component of the modern logistics system.

[0003] Container trucks have large tonnage and are equipped with high-power engines. When container trucks are in operation, high-power engines will generate large vibrations and noise. The large tonnage of container trucks will also cause large vibrations and noises caused by the friction between the truck tires and the road surface. The high-power engines and their main transmission components of container trucks are often installed under the seats in the cab. When the truck is in operation, the vibrations and noises generated by the high-power engines and the vibrations and noises generated by the friction between the tires and the road surface will be transmitted to the drivers and passengers in the cab through the cab floor and seats. Long-term vibrations and noises will not only affect the driving safety of container trucks, but also cause damage to the health of drivers and passengers, and reduce the comfort of drivers and passengers. In addition, high-power engines will also generate high heat, which will be directly transmitted to the drivers and passengers sitting in the seats through the cab floor and seats during the operation of the truck. In the cold winter, the seat temperature is low, which brings discomfort to the driver who has just entered the cab.

[0004] The work intensity of container truck drivers is very high, and they need a driving environment that ensures safe work. If a seat cushion with good shockproof, sound-absorbing and heat-insulating functions is placed on the container driver's chair, the problems caused by the above vibration, noise and temperature difference to the working environment of container truck drivers can be solved to a certain extent without changing the existing container truck design parameters and vehicle configuration, thus improving the working comfort of container truck drivers and contributing to the safe driving and health of container truck drivers.

[0005] There are many varieties of existing car seat cushions. Seat cushions used in summer are usually made of linen, bamboo or leather. Although they can provide a certain sense of coolness, they are not good in terms of shock absorption, sound insulation and heat preservation. Seat cushions used in winter are mostly made of flannel, wool or down. Although they are soft and warm, they are obviously lacking in breathability, shock absorption and sound insulation. There are also seat cushions made of polymer materials such as rubber, sponge or foam plastics. Although they have improved in shock absorption and sound insulation, they are still not enough to meet the needs. Moreover, the problem of poor air permeability of polymer material seat cushions is more prominent, which will make people feel uncomfortable after riding for a long time. Summary of the invention

[0006] Aiming at the defects of existing automobile seat pads such as poor shock absorption, sound absorption and heat insulation effects, airtightness and discomfort, the present invention provides a new automobile seat pad and a preparation method thereof, which has excellent shock absorption, heat insulation and sound absorption properties.

[0007] The invention provides a method for preparing a shock-absorbing, heat-insulating and sound-absorbing TPU automobile seat pad. The method comprises coating the surface of a hollow lattice support body of a TPU automobile seat pad having a hollow structure formed by a selective laser sintering (SLS) technology with an epoxy resin-based micro-foaming coating having a heat-insulating and sound-absorbing function, and forming an epoxy resin-based micro-foaming coating anchored on the surface of the hollow lattice support body after curing. Hollow glass microspheres with silicon dioxide nanoparticles deposited on the surface are dispersed in the epoxy resin-based micro-foaming coating.

[0008] The preparation method of the shock-absorbing, heat-insulating and sound-absorbing TPU automobile seat pad provided by the present invention comprises the following steps:

[0009] Step 1.1: pre-treating the surface of the glass hollow microspheres by alkali etching;

[0010] Step 1.2: pre-treating the etched glass hollow microspheres with dopamine to form a polydopamine layer on the surface;

[0011] Step 1.3: Depositing silica nanoparticles on the surface of glass hollow microspheres pre-treated with dopamine organication;

[0012] Step 1.4: preparing a mixture containing epoxy resin and polyurethane;

[0013] Step 1.5: mixing the glass hollow microspheres deposited with nano-silica, a mixture containing epoxy resin and polyurethane, a curing agent, a curing accelerator, and nano-silica to obtain an epoxy resin-based micro-foaming coating with heat insulation and sound absorption functions;

[0014] Step 2.1: Prepare a dry and clean TPU automobile seat cushion part with a hollow structure formed by selective laser sintering;

[0015] Step 2.2: placing the TPU automobile seat pad parts and the epoxy resin-based micro-foam coating in a vacuum dipping device;

[0016] Step 2.3: Dip coating under vacuum conditions;

[0017] Step 2.4: Remove excess paint and allow the TPU car seat pad to dry naturally;

[0018] Step 3.1: heating and curing the TPU automobile seat cushion part coated with the micro-foam coating;

[0019] Step 3.2: After cooling, the shock-absorbing, heat-insulating and sound-absorbing TPU car seat pad is obtained.

[0020] The present invention adopts the selective laser sintering technology to form a TPU hollow structure seat cushion component, and utilizes the advantages of TPU such as high flexibility, good ductility, large deformation of the three-dimensional lattice support body with external stress changes, good resilience, etc., to effectively improve the shock absorption effect of the car seat cushion. TPU is a flexible polymer with the advantages of high ductility, soft texture, good mechanical properties, high resilience, etc., and low thermal conductivity and good thermal insulation performance. The hollow structure component is a lattice network three-dimensional system structure composed of nodes and beams or pillars, which has stable mechanical properties, good permeability and obvious weight reduction effect, can increase air circulation, enhance the air permeability of the substrate, and also has outstanding deformation and resilience performance advantages with external stress changes, can absorb energy, disperse impact force, and improve shock absorption effect. Selective laser sintering is one of the additive manufacturing technologies. It is a technology that slices a 3D object into computer-modeled layers through a computer-aided system, and then deposits each layer of material together to finally obtain a part. It is an ideal technology for preparing hollow structure components. The TPU hollow structure parts prepared by selective laser sintering are used as container truck car seat pads, which not only meet the requirements of breathability and ergonomics, but also meet the requirements of large deformation and high rebound shock absorption.

[0021] On the surface of each lattice support of the TPU hollow structure seat cushion, a layer of micro-foam coating firmly attached to the lattice support is constructed through post-processing technology, which can improve the sound absorption and heat insulation effect. To achieve this effect, this micro-foam coating must meet the following requirements: First, the micro-foam coating is full of micropores. When the sound waves that transmit sound and the phonons that transmit heat pass through the hollow structure and along the surface of the hollow structure lattice support, the micropores inside the micro-foam coating hinder the sound waves and phonons, thereby improving the sound absorption and heat insulation effect. Second, the micro-foam coating cannot block the original hollow cavity of the product, and continue to maintain the permeability and breathability of the seat cushion. Third, the micro-foam coating itself should have a certain deformation ability, and can deform accordingly with the compression and rebound process of the hollow lattice support of the seat cushion during the operation of the car. Fourth, the micro-foam coating must have sufficient strength and strong adhesion to the surface of the TPU hollow lattice support, and can adapt to the strength and fastness requirements of the micro-foam coating for the compression and rebound of the seat cushion. The micro-foam coating of the present invention, in addition to epoxy resin, also contains hollow glass microspheres, polyurethane powder, nano-silicon dioxide, etc. Among them, the hollow glass microspheres serve as a physical foaming micropore source to form a micro-foam structure in the coating; the polyurethane powder serves as a toughening component of the epoxy resin, which toughens the epoxy resin matrix after curing to ensure that the epoxy resin-based micro-foam coating does not suffer obvious brittle fracture during large deformation and high rebound of the seat cushion, thereby improving the service life of the coating; nano-silicon dioxide can improve the hardness, rigidity and wear resistance of the epoxy resin coating, and its main role in the coating is to balance the partial loss of strength and rigidity of the coating caused by the polyurethane toughening component.

[0022] The vacuum impregnation process is used to remove the residual TPU raw material powder and dust on the surface of the car seat cushion parts, and the residual air in the micro-voids on the surface of the parts is removed. The car seat cushion parts are dip-coated so that the coating is not only coated on the surface of the car seat cushion parts, but also on the surface of all lattice supports inside the hollow structure of the parts. At the same time, the liquid coating also penetrates into the micro-pores unique to the surface of the selective laser sintered parts through surface penetration. The car seat cushion parts after the surface coating is cured, and a micro-foam coating is formed on the surface of the lattice support of the TPU hollow structure seat cushion parts. In the cured micro-foam coating, the hollow glass micro-beads evenly distributed in the coating act as pores, forming a cavity structure that blocks the conduction of sound waves and phonons, so that the car seat cushion has sound absorption and heat insulation effects; and the coating that penetrates into the micro-pores on the surface of the lattice support of the hollow structure of the TPU car seat cushion becomes micro-nails after curing, which firmly anchors the micro-foam coating on the surface of the lattice support, which can effectively improve the service life of the micro-foam coating.

[0023] Further, in step 1.1: 5 to 20 parts by mass of hollow glass microspheres are placed in 100 to 110 parts by mass of deionized water, and stirred at room temperature for 1 to 2 hours; then allowed to stand at room temperature for 20 to 24 hours, the suspended hollow glass microspheres are taken out, and dried until the mass of the hollow glass microspheres remains unchanged; then 25 to 30 parts by mass of a 1 mol / L sodium hydroxide solution are added to the hollow glass microspheres, and the hollow glass microspheres are etched at 100° C. for 4 to 6 hours, stirred during the etching process, and then centrifuged to separate the hollow glass microspheres, and washed with pure water until the pH value is 7, and then the hollow glass microspheres are dried until the mass remains unchanged to obtain alkali-etched hollow glass microspheres.

[0024] Furthermore, in step 1.2: the etched glass hollow microspheres are placed in a dopamine Tris buffer solution with a pH value of 8 to 9, mechanically stirred at room temperature, and reacted for 24 hours to obtain glass hollow microspheres pretreated with dopamine organication.

[0025] Furthermore, in step 1.3: prepare a dopamine aqueous solution containing 2 parts by mass of dopamine and 1000 parts by mass of deionized water, and adjust the pH to 8.5 with a tris-hydroxymethylaminomethane hydrochloride (Tris-HCl) solution; add 0.5 to 2 parts by mass of nano-silica and 5 to 15 parts by mass of organically pretreated hollow glass microspheres, stir for 1 h to 2 h, so that the polydopamine on the surface of the hollow glass microspheres is fully adsorbed by the nano-silica, and then centrifuge and wash to obtain hollow glass microspheres with surface deposited silica nanoparticles.

[0026] Furthermore, in step 1.4: 8 to 20 parts by mass of polyurethane powder are added to 20 to 30 parts by mass of an organic solvent, and the mixture is mechanically stirred at room temperature for 10 to 12 hours to obtain a polyurethane solution; 50 to 70 parts by mass of epoxy resin are added to the polyurethane solution, and the mixture is mechanically stirred at room temperature for 20 to 24 hours; and then the mixture of the epoxy resin and the polyurethane is heated under continuous stirring to evaporate the organic solvent therein until the mass of the mixture does not change, thereby obtaining a mixture of the epoxy resin and the polyurethane.

[0027] Furthermore, in step 1.5: 5 to 10 parts by mass of hollow glass microspheres deposited with nano-silica, 55 to 90 parts by mass of a mixture of epoxy resin and polyurethane, 33 to 49 parts by mass of a curing agent, 1 to 5 parts by mass of a curing accelerator, and 1 to 5 parts by mass of nano-silica are placed in a stirring tank and stirred for 0.5 to 1 hour to obtain an epoxy resin-based micro-foaming coating with heat insulation and sound absorption functions.

[0028] Furthermore, in step 2.1: an ethanol solution with a concentration of 20% to 30% is used to wash the surface layer and hollow internal impurities of the TPU automobile seat cushion component with a hollow structure formed by SLS technology, and then dried until the quality remains unchanged.

[0029] Furthermore, in step 2.2: the washed and dried TPU car seat pad with a hollow structure is placed in a dipping tank of a vacuum dipping equipment, and the epoxy resin-based micro-foaming coating with heat insulation and sound absorption functions is injected into the dipping tank until the TPU car seat pad is immersed, and the dipping tank is closed.

[0030] Furthermore, in step 2.3: the vacuum coating equipment is evacuated at room temperature until the vacuum degree is less than -0.09 MPa; and then the vacuum coating tank is slowly rotated and slightly vibrated for 30 to 120 minutes by the vacuum coating equipment.

[0031] Furthermore, in step 2.4: after the vacuum dipping is completed, the vacuum of the vacuum dipping equipment is released, the dipping tank is opened, and the automobile seat cushion parts are taken out until there is no obvious dripping of paint; then they are naturally dried at room temperature for 10 to 12 hours to obtain TPU automobile seat cushion parts with a hollow structure coated with an epoxy resin-based micro-foaming coating with heat insulation and sound absorption functions.

[0032] Furthermore, in step 3.1: the TPU automobile seat cushion parts are hung in a blast oven and cured according to the following curing mechanism: 55-70°C / 10-40min; 70-105°C / 10-120min.

[0033] Furthermore, in step 3.2: the cured TPU car seat pad is hung in the air to cool naturally to room temperature, so as to obtain a TPU car seat pad having a micro-foamed coating with heat insulation and sound absorption functions.

[0034] Preferably, the organic solvent is one of N-methylpyrrolidone, dimethylacetamide, dimethyl sulfoxide, and dimethylformamide; the curing agent is one of ethylenediamine, diethylenetriamine, and methyltetrahydrophthalic anhydride; the curing accelerator is one of glacial acetic acid and 2,4,6-tris(dimethylaminomethyl)phenol; the polyurethane is a polyester polyurethane; and the particle size of the hollow glass microspheres is 5 to 30 μm.

[0035] By means of the preparation method of the shock-absorbing, heat-insulating and sound-absorbing TPU automobile seat pad, a car seat pad having excellent shock-absorbing, heat-insulating and sound-absorbing properties can be prepared.

[0036] Beneficial Effects

[0037] The integral car seat pad with a hollow structure made of TPU material printed by selective laser sintering in the scheme of the present invention has the characteristics of large deformation, high resilience and good air permeability, which is more in line with the ergonomic requirements of the seat pad for drivers and passengers during the operation of the car, and exhibits good shock absorption effect and ride comfort.

[0038] The epoxy resin-based heat-insulating and sound-absorbing coating in the scheme of the present invention adopts hollow glass microspheres as the physical foaming micropore source, and has the characteristics of thin foaming layer (coating) and fine and uniform micropores. The micro-foam body is only attached to the surface of the lattice support body but does not block the hollow cavity. It effectively improves the effect of heat insulation and sound absorption during automobile operation, and continues to maintain the characteristics of air permeability, large deformation and high rebound.

[0039] In the epoxy resin-based heat-insulating and sound-absorbing micro-foaming coating, polyurethane powder enhances the toughness of the coating, and nano-silicon dioxide can enhance the wear resistance of the micro-foaming coating of the hollow structure lattice support of the seat cushion during the compression-rebound process; the coating penetrates into the micro-voids on the surface of the selective laser sintered TPU part during the coating process, and forms an anchoring structure after curing, thereby improving the adhesion of the coating to the TPU substrate and increasing the service life of the car seat cushion.

[0040] The scheme of the present invention adopts a post-treatment coating process, does not change the selective laser sintering process characteristics of the TPU pure raw material powder, and the coating and curing processes are simple, efficient, low-cost, and convenient for industrial production. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 It is a plan view of the hollow lattice structure of the TPU car seat pad;

[0042] Figure 2 This is a partial plan view of the epoxy resin-based micro-foaming coating on the hollow cell structure of the shock-absorbing, heat-insulating and sound-absorbing TPU car seat pad. DETAILED DESCRIPTION

[0043] The present invention is further illustrated by specific examples below. These examples are exemplary and are intended to illustrate the problem and explain the present invention, but are not intended to be limiting.

[0044] The preparation, coating and curing of the epoxy resin-based heat-insulating and sound-absorbing micro-foaming coating in the following embodiments are carried out according to the following steps:

[0045] Step 1: putting 20 parts by mass of hollow glass microspheres into 100 parts by mass of deionized water, stirring at room temperature for 2 hours, and stirring at a rate of 200 r / min; then standing at room temperature for 20 hours, taking out the suspended hollow glass microspheres, and drying at 50° C. for 4 hours until the mass of the hollow glass microspheres remains unchanged; then adding 25 parts by mass of a 1 mol / L sodium hydroxide solution to the hollow glass microspheres, etching at 100° C. for 4 hours, stirring during the etching process, and stirring at a rate of 200 r / min, centrifuging, and washing with pure water to a pH value of 7, and then drying the hollow glass microspheres at 50° C. for 8 hours until the mass of the hollow glass microspheres remains unchanged, to obtain etched hollow glass microspheres;

[0046] Step 2: placing the etched hollow glass microspheres into a dopamine-Tris buffer solution with a pH value of 9, mechanically stirring at room temperature at a stirring rate of 60 r / min, and reacting for 24 hours to obtain hollow glass microspheres pretreated with organication;

[0047] Step 3: Weigh 2 parts by mass of dopamine and add it to 1000 parts by mass of deionized water, stir and dissolve to prepare a dopamine aqueous solution, and adjust the pH to 8.5 with 1 mol / L tris(hydroxymethyl)aminomethane hydrochloride) (Tris-HCl) solution; add 2 parts by mass of nano-silica and 15 parts by mass of organically pretreated hollow glass microspheres, and stir magnetically for 2 hours to allow the polydopamine on the surface of the hollow glass microspheres to fully adsorb each other with the nano-silica, and then centrifuge at a speed of 3000 r / min for 10 minutes, take out, and prepare hollow glass microspheres with surface deposited nanoparticles after washing.

[0048] Step 4: adding a certain mass part of polyurethane powder to 20 mass parts of organic solvent, mechanically stirring for 12 hours at room temperature, and a stirring rate of 60r / min to obtain a polyurethane solution; adding 70 mass parts of epoxy resin to the above polyurethane solution, mechanically stirring for 24 hours at room temperature, and a stirring rate of 100r / min; then heating the above epoxy resin / polyurethane mixture to 60°C under continuous stirring to evaporate the organic solvent therein until the mass of the mixture does not change, to obtain an epoxy resin / polyurethane mixture;

[0049] Step 5: At room temperature, put a certain mass parts of nano-silica deposited glass hollow microspheres, 70 mass parts of epoxy resin / polyurethane mixture, 49 mass parts of curing agent, 4 mass parts of curing accelerator, and a certain mass parts of nano-silica into a stirring tank, and mechanically stir for 1 hour at a stirring speed of 200r / min to obtain an epoxy resin-based micro-foaming coating with heat insulation and sound absorption functions.

[0050] Step 6: Immerse the TPU car seat cushion with a hollow structure formed by SLS technology in a 30% ethanol solution at room temperature, wash the surface layer and the impurities inside the hollow for 60 minutes, and constantly turn and vibrate during the washing process; place the washed TPU car seat cushion in a 55°C blast oven and dry it for 8 hours until the quality of the car seat cushion remains unchanged, then take it out to obtain a washed and dried TPU car seat cushion with a hollow structure;

[0051] Step 7: placing the washed and dried TPU car seat pad with a hollow structure in a dipping tank of a vacuum dipping equipment, injecting an epoxy resin-based micro-foaming coating with heat insulation and sound absorption functions into the dipping tank until the TPU car seat pad is immersed, and closing the dipping tank;

[0052] Step 8: Evacuate the vacuum coating equipment at room temperature until the vacuum degree is less than -0.09MPa; then slowly rotate and slightly vibrate the coating tank through the vacuum coating equipment for 120 minutes;

[0053] Step nine: After the vacuum dipping is completed, release the vacuum of the vacuum dipping equipment, open the dipping tank, take out the car seat cushion with a clamping mechanism, and slowly rotate and tilt the TPU car seat cushion for 4 hours to remove and drip excess paint on the surface of the TPU car seat cushion and inside the hollow structure until there is no obvious paint dripping; then dry naturally at room temperature for 10 hours to obtain a TPU car seat cushion with a hollow structure coated with an epoxy resin-based micro-foaming coating with heat insulation and sound absorption functions.

[0054] Step 10: Hang the TPU car seat cushion parts in a blast oven and cure them according to the following curing mechanism: 70℃ / 40min; 105℃ / 120min. After curing, take out the TPU car seat cushion parts;

[0055] Step 11: Hang the cured TPU car seat pad in the air and cool it naturally to room temperature to obtain a TPU car seat pad with a micro-foamed coating having heat insulation and sound absorption functions.

[0056] Figure 1 The hollow lattice structure of the SLS-molded TPU car seat cushion is shown, in which multiple connecting nodes connect multiple rod-shaped components to form a network structure; Figure 2 The cross-sectional structure of the hollow crystal cell of the prepared shock-absorbing, heat-insulating and sound-absorbing TPU car seat pad is illustrated, wherein the interior is a crystal cell structure of TPU material, the outer layer is an epoxy resin-based micro-foam coating, and a large number of hollow glass microspheres are dispersed in the epoxy resin-based micro-foam coating.

[0057] Example 1

[0058] According to the above steps 1 to 11, an epoxy resin-based micro-foamed coating with heat insulation and sound absorption functions is prepared, wherein: 10 parts by mass of nano-silica deposited glass hollow microspheres, the particle size of the glass hollow microspheres is 20 μm, 3 parts by mass of nano-silica, 55 parts by mass of polyurethane powder / epoxy resin (including 15 parts by mass of polyurethane powder), 49 parts by mass of curing agent ethylenediamine, 4 parts by mass of curing accelerator glacial acetic acid, mechanical stirring for 1 hour, and the stirring speed is 200 r / min.

[0059] Example 2

[0060] According to the above steps 1 to 11, an epoxy resin-based micro-foamed coating with heat insulation and sound absorption functions is prepared, wherein: 20 parts by mass of nano-silica deposited glass hollow microspheres, the particle size of the glass hollow microspheres is 20 μm, 3 parts by mass of nano-silica, 55 parts by mass of polyurethane powder / epoxy resin (including 15 parts by mass of polyurethane powder), 49 parts by mass of curing agent ethylenediamine, 4 parts by mass of curing accelerator glacial acetic acid, mechanical stirring for 1 hour, and the stirring speed is 200 r / min.

[0061] Example 3

[0062] According to the above steps 1 to 11, an epoxy resin-based micro-foamed coating with heat insulation and sound absorption functions is prepared, wherein: 30 parts by mass of nano-silica deposited glass hollow microspheres, the particle size of the glass hollow microspheres is 20 μm, 3 parts by mass of nano-silica, 55 parts by mass of polyurethane powder / epoxy resin (including 15 parts by mass of polyurethane powder), 49 parts by mass of curing agent ethylenediamine, 4 parts by mass of curing accelerator glacial acetic acid, mechanical stirring for 1 hour, and the stirring speed is 200 r / min.

[0063] Example 4

[0064] According to the above steps 1 to 11, an epoxy resin-based micro-foamed coating with heat insulation and sound absorption functions is prepared, wherein: 20 parts by mass of nano-silica deposited glass hollow microspheres, the particle size of the glass hollow microspheres is 5 μm, 3 parts by mass of nano-silica, 55 parts by mass of polyurethane powder / epoxy resin (including 15 parts by mass of polyurethane powder), 49 parts by mass of curing agent ethylenediamine, 4 parts by mass of curing accelerator glacial acetic acid, mechanical stirring for 1 hour, and the stirring speed is 200 r / min.

[0065] Example 5

[0066] According to the above steps 1 to 11, an epoxy resin-based micro-foamed coating with heat insulation and sound absorption functions is prepared, wherein: 20 parts by mass of nano-silica deposited glass hollow microspheres, 35 μm glass hollow microspheres, 3 parts by mass of nano-silica, 55 parts by mass of polyurethane powder / epoxy resin (including 15 parts by mass of polyurethane powder), 49 parts by mass of curing agent ethylenediamine, 4 parts by mass of curing accelerator glacial acetic acid, mechanical stirring for 1 hour, and the stirring speed is 200 r / min.

[0067] Example 6

[0068] According to the above steps 1 to 11, an epoxy resin-based micro-foamed coating with heat insulation and sound absorption functions is prepared, wherein: 20 parts by mass of nano-silica deposited glass hollow microspheres, the particle size of the glass hollow microspheres is 20 μm, 1 part by mass of nano-silica, 55 parts by mass of polyurethane powder / epoxy resin (including 15 parts by mass of polyurethane powder), 49 parts by mass of curing agent ethylenediamine, 4 parts by mass of curing accelerator glacial acetic acid, mechanical stirring for 1 hour, and the stirring speed is 200 r / min.

[0069] Example 7

[0070] According to the above steps 1 to 11, an epoxy resin-based micro-foamed coating with heat insulation and sound absorption functions is prepared, wherein: 20 parts by mass of nano-silica deposited glass hollow microspheres, the particle size of the glass hollow microspheres is 20 μm, 5 parts by mass of nano-silica, 55 parts by mass of polyurethane powder / epoxy resin (including 15 parts by mass of polyurethane powder), 49 parts by mass of curing agent ethylenediamine, 4 parts by mass of curing accelerator glacial acetic acid, mechanical stirring for 1 hour, and the stirring speed is 200 r / min.

[0071] Example 8

[0072] According to the above steps 1 to 11, an epoxy resin-based micro-foamed coating with heat insulation and sound absorption functions is prepared, wherein: 20 parts by mass of nano-silica deposited glass hollow microspheres, the particle size of the glass hollow microspheres is 20 μm, 3 parts by mass of nano-silica, 55 parts by mass of polyurethane powder / epoxy resin (including 10 parts by mass of polyurethane powder), 49 parts by mass of curing agent ethylenediamine, 4 parts by mass of curing accelerator glacial acetic acid, mechanical stirring for 1 hour, and the stirring speed is 200 r / min.

[0073] Example 9

[0074] According to the above steps 1 to 11, an epoxy resin-based micro-foamed coating with heat insulation and sound absorption functions is prepared, wherein: 20 parts by mass of nano-silica deposited glass hollow microspheres, the particle size of the glass hollow microspheres is 20 μm, 3 parts by mass of nano-silica, 55 parts by mass of polyurethane powder / epoxy resin (including 20 parts by mass of polyurethane powder), 49 parts by mass of curing agent ethylenediamine, 4 parts by mass of curing accelerator glacial acetic acid, mechanical stirring for 1 hour, and the stirring speed is 200 r / min.

[0075] Example 10

[0076] According to the above steps 1 to 11, an epoxy resin-based micro-foamed coating with heat insulation and sound absorption functions is prepared, wherein: 20 parts by mass of nano-silica deposited glass hollow microspheres, the particle size of the glass hollow microspheres is 20 μm, 3 parts by mass of nano-silica, 55 parts by mass of polyurethane powder / epoxy resin (including 30 parts by mass of polyurethane powder), 49 parts by mass of curing agent ethylenediamine, 4 parts by mass of curing accelerator glacial acetic acid, mechanical stirring for 1 hour, and the stirring speed is 200 r / min.

[0077] Comparative Example 1

[0078] A test sample was prepared according to the above steps 1 to 11, wherein the epoxy resin-based micro-foam coating does not contain glass hollow microspheres, nano-silica, and polyurethane powder. Specifically, the epoxy resin is 55 parts by mass, 49 parts by mass of curing agent ethylenediamine, and 4 parts by mass of curing accelerator glacial acetic acid. The mixture was mechanically stirred for 1 hour at a stirring speed of 200 r / min to obtain an epoxy resin-based micro-foam coating with heat insulation and sound absorption functions.

[0079] Comparative Example 2

[0080] The test sample was prepared according to the above steps 1 to 11, wherein the TPU automobile seat cushion component with a hollow structure formed by SLS technology was not coated.

[0081] Comparative Example 3

[0082] A test sample was prepared according to the above steps 1 to 11, wherein the epoxy resin-based micro-foam coating does not contain polyurethane powder, specifically: 20 parts by mass of nano-silica deposited glass hollow microspheres with a particle size of 20 μm, 3 parts by mass of nano-silica, 55 parts by mass of epoxy resin, 49 parts by mass of curing agent ethylenediamine, and 4 parts by mass of curing accelerator glacial acetic acid. The mixture was mechanically stirred for 1 hour at a stirring speed of 200 r / min to obtain an epoxy resin-based micro-foam coating with heat insulation and sound absorption functions.

[0083] Comparative Example 4

[0084] A test sample was prepared according to the above steps 1 to 11, wherein the epoxy resin-based micro-foamed coating does not contain nano-silica, specifically: 20 parts by mass of nano-silica-deposited glass hollow microspheres, 20 μm glass hollow microspheres, 55 parts by mass of polyurethane powder / epoxy resin (including 20 parts by mass of polyurethane powder), 49 parts by mass of curing agent ethylenediamine, 4 parts by mass of curing accelerator glacial acetic acid, mechanically stirred for 1 hour at a stirring speed of 200 r / min, to obtain an epoxy resin-based micro-foamed coating with heat insulation and sound absorption functions.

[0085] Comparative Example 5

[0086] The TPU solid test sample is prepared according to the above steps 1 to 11, wherein the epoxy resin-based micro-foam coating does not contain glass hollow microspheres and nano-silica, specifically: 55 parts by mass of polyurethane powder / epoxy resin (including 20 parts by mass of polyurethane powder), 49 parts by mass of curing agent ethylenediamine, 4 parts by mass of curing accelerator glacial acetic acid, mechanical stirring for 1 hour, and the stirring speed is 200r / min to obtain an epoxy resin-based micro-foam coating with heat insulation and sound absorption functions.

[0087] Effect verification

[0088] The following performance tests were performed on the samples obtained from Examples 1 to 10 and Comparative Examples 1 to 5: Compression strength test was performed in accordance with GB / T 7759-1996 standard, the constant compression distance was 24 mm, and the sample size was: 50 m long, 25 m wide, and 50 m high. Sound absorption coefficient test was performed in accordance with GB / T 20247-2006 standard, and the volume of the reverberation chamber was 226 m 3 , effective frequency range is 1000Hz, average reverberation time is 2.1~2.3s, low frequency cutoff frequency is 63Hz, sound field uniformity is 1.2~2.7dB, sample area is 10m 2 The thermal conductivity test was carried out according to GB / T 10294-2008 standard.

[0089] The test results are shown in Table 1.

[0090] Table 1 Performance test results

[0091]

[0092] It can be seen from the data analysis in Table 1 that the shock-absorbing, heat-insulating and sound-absorbing TPU car seat pads prepared in various embodiments have excellent heat-insulating and sound-absorbing properties, and excellent compression and rebound properties.

[0093] It can be seen from the data of Examples 1 to 3 that the thermal conductivity decreases with the increase of the mass fraction of the hollow glass microspheres, the sound absorption coefficient increases with the increase of the mass fraction of the hollow glass microspheres, and the thermal insulation and sound absorption performance becomes better; it can be seen from the data of Examples 2, 4, and 5 that the thermal conductivity increases with the increase of the particle size of the hollow glass microspheres, the sound absorption coefficient decreases with the increase of the particle size of the hollow glass microspheres, and the thermal insulation and sound absorption performance becomes worse. This is because the interior of the hollow glass microspheres is a cavity structure, and these tiny cavities are dispersed in the surface layer of the structure, which can effectively hinder the conduction of heat, thereby improving the thermal insulation performance of the material. On the other hand, under the same mass fraction, the smaller the particle size of the hollow glass microspheres, the more air cavities are formed, and the better the thermal insulation and sound absorption effect. Compared with Reference Example 1, Reference Example 2 and Reference Example 5, the thermal conductivity of Examples 1 to 10 is significantly smaller and the sound absorption coefficient is larger.

[0094] From the data of Examples 1, 2, 3, 6, 7, 8, 9, 10, and Comparative Examples 3 and 4, it can be seen that the compression deformation decreases with the increase in the mass fraction of hollow glass microspheres, and increases with the increase in the mass fraction of polyurethane powder. This is because the polyurethane powder has a toughening effect on the heat-insulating and sound-absorbing coating, while the nano-silica-deposited hollow glass microspheres and nano-silica have a reinforcing effect. Therefore, as the content of polyurethane powder increases, the shock-absorbing performance of the hollow structure shock-absorbing and heat-insulating and sound-absorbing TPU car seat pad improves, and as the content of nano-silica increases, the shock-absorbing performance of the hollow structure shock-absorbing and heat-insulating and sound-absorbing TPU car seat pad decreases. As can be seen from Comparative Example 5, the compression deformation and rebound rate of the hollow structure shock-absorbing and heat-insulating and sound-absorbing TPU car seat pad are much higher than those of solid TPU, and have good shock-absorbing function.

[0095] The above experiments and results show that the heat insulation and sound absorption properties of the hollow structure shock-absorbing, heat-insulating and sound-absorbing TPU car seat pad are affected by the mass of glass beads and their particle size, while the shock absorption performance is affected by the mass of hollow glass beads, the mass of silica and the mass of polyurethane, and it has good shock-absorbing, heat-insulating and sound-absorbing functions.

[0096] The above embodiments are exemplary, and their purpose is to illustrate the technical concept and features of the present invention so that people familiar with the technology in this field can understand the content of the present invention and implement it accordingly, and they cannot be used to limit the protection scope of the present invention. Any equivalent changes or modifications made according to the spirit of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for preparing a shock-absorbing, heat-insulating, and sound-absorbing TPU automobile seat pad, characterized in that: An epoxy resin-based micro-foaming coating with heat insulation and sound absorption functions is coated on the surface of a hollow lattice support of a TPU car seat pad with a hollow structure formed by selective laser sintering (SLS) technology, and after curing, an epoxy resin-based micro-foaming coating anchored on the surface of the hollow lattice support is formed; hollow glass microspheres with silica nanoparticles deposited on the surface are dispersed in the epoxy resin-based micro-foaming coating.

2. The method for preparing the shock-absorbing, heat-insulating and sound-absorbing TPU car seat pad according to claim 1, characterized in that: The following steps are involved: Step 1.1: pre-treating the surface of the glass hollow microspheres by alkali etching; Step 1.2: pre-treating the etched glass hollow microspheres with dopamine to form a polydopamine layer on the surface; Step 1.3: Depositing silica nanoparticles on the surface of glass hollow microspheres pre-treated with dopamine organication; Step 1.4: preparing a mixture containing epoxy resin and polyurethane; Step 1.5: mixing the glass hollow microspheres deposited with nano-silica, a mixture containing epoxy resin and polyurethane, a curing agent, a curing accelerator, and nano-silica to obtain an epoxy resin-based micro-foaming coating with heat insulation and sound absorption functions; Step 2.1: Prepare a dry and clean TPU automobile seat cushion part with a hollow structure formed by selective laser sintering; Step 2.2: placing the TPU automobile seat pad parts and the epoxy resin-based micro-foam coating in a vacuum dipping device; Step 2.3: Dip coating under vacuum conditions; Step 2.4: Remove excess paint and allow the TPU car seat pad to dry naturally; Step 3.1: heating and curing the TPU automobile seat cushion part coated with the micro-foam coating; Step 3.2: After cooling, the shock-absorbing, heat-insulating and sound-absorbing TPU car seat pad is obtained.

3. The method for preparing the shock-absorbing, heat-insulating and sound-absorbing TPU car seat pad according to claim 2, characterized in that: In step 1.1: 5 to 20 parts by mass of hollow glass microspheres are placed in 100 to 110 parts by mass of deionized water, and stirred at room temperature for 1 to 2 hours; then the hollow glass microspheres are allowed to stand at room temperature for 20 to 24 hours, the hollow glass microspheres suspended therein are taken out, and dried until the mass of the hollow glass microspheres remains unchanged; then 25 to 30 parts by mass of a 1 mol / L sodium hydroxide solution are added to the hollow glass microspheres, and the hollow glass microspheres are etched at 100° C. for 4 to 6 hours, with stirring during the etching process, and then the hollow glass microspheres are separated by centrifugation, and washed with pure water until the pH value is 7, and then the hollow glass microspheres are dried until the mass remains unchanged to obtain alkali-etched hollow glass microspheres.

4. The method for preparing the shock-absorbing, heat-insulating and sound-absorbing TPU car seat pad according to claim 2, characterized in that: In step 1.2: the etched glass hollow microspheres are placed in a dopamine Tris buffer solution with a pH value of 8 to 9, mechanically stirred at room temperature, and reacted for 24 hours to obtain glass hollow microspheres pretreated with dopamine organication.

5. The method for preparing the shock-absorbing, heat-insulating and sound-absorbing TPU car seat pad according to claim 2, characterized in that: In step 1.3: prepare a dopamine aqueous solution containing 2 parts by mass of dopamine and 1000 parts by mass of deionized water, adjust the pH to 8.5 with a tris-hydroxymethylaminomethane hydrochloride (Tris-HCl) solution; add 0.5-2 parts by mass of nano-silica and 5-15 parts by mass of organically pretreated hollow glass microspheres, stir for 1h-2h to allow the polydopamine on the surface of the hollow glass microspheres to be fully adsorbed by the nano-silica, and then centrifuge and wash to obtain hollow glass microspheres with silica nanoparticles deposited on the surface.

6. The method for preparing the shock-absorbing, heat-insulating and sound-absorbing TPU car seat pad according to claim 2, characterized in that: In step 1.4: add 8 to 20 parts by mass of polyurethane powder to 20 to 30 parts by mass of organic solvent, and mechanically stir at room temperature for 10 to 12 hours to obtain a polyurethane solution; add 50 to 70 parts by mass of epoxy resin to the above polyurethane solution, and mechanically stir at room temperature for 20 to 24 hours; then heat the mixture of the epoxy resin and polyurethane under continuous stirring to evaporate the organic solvent therein until the mass of the mixture does not change, thereby obtaining a mixture of the epoxy resin and polyurethane.

7. The method for preparing the shock-absorbing, heat-insulating and sound-absorbing TPU car seat pad according to claim 2, characterized in that: In step 1.5: 5-10 parts by mass of hollow glass microspheres deposited with nano-silica, 55-90 parts by mass of a mixture of epoxy resin and polyurethane, 33-49 parts by mass of a curing agent, 1-5 parts by mass of a curing accelerator, and 1-5 parts by mass of nano-silica are placed in a stirring tank and stirred for 0.5-1 hour to obtain an epoxy resin-based micro-foaming coating with heat insulation and sound absorption functions.

8. The method for preparing the shock-absorbing, heat-insulating and sound-absorbing TPU car seat pad according to claim 2, characterized in that: In step 2.1: using an ethanol solution with a concentration of 20% to 30%, washing the surface layer and the hollow internal impurities of the TPU automobile seat cushion having a hollow structure formed by SLS technology, and then drying until the quality remains unchanged; In step 2.2: the washed and dried TPU car seat cushion with a hollow structure is placed in a dipping tank of a vacuum dipping device, and an epoxy resin-based micro-foaming coating with heat insulation and sound absorption functions is injected into the dipping tank until the TPU car seat cushion is immersed, and the dipping tank is closed; In step 2.3: evacuate the vacuum coating equipment at room temperature until the vacuum degree is less than -0.09MPa; then, the vacuum coating equipment is used to slowly rotate and slightly vibrate the coating tank for 30 to 120 minutes; In step 2.4: after the vacuum dipping is completed, the vacuum of the vacuum dipping equipment is released, the dipping tank is opened, and the car seat cushion parts are taken out until there is no obvious paint dripping; then they are naturally dried at room temperature for 10 to 12 hours to obtain TPU car seat cushion parts with a hollow structure coated with epoxy resin-based micro-foaming paint with heat insulation and sound absorption functions.

9. The method for preparing the shock-absorbing, heat-insulating and sound-absorbing TPU car seat pad according to claim 2, characterized in that: In step 3.1: hang the TPU car seat cushion parts in a blast oven and cure them according to the following curing mechanism: 55~70℃ / 10~40min; 70~105℃ / 10~120min; In step 3.2: the cured TPU car seat pad is hung in the air to cool naturally to room temperature, thereby obtaining a TPU car seat pad having a micro-foamed coating with heat insulation and sound absorption functions.

10. A shock-absorbing, heat-insulating, and sound-absorbing TPU car seat pad, characterized in that: The method is prepared according to any one of claims 1 to 9.

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