Lightweight durable soundproof wheel cover based on pet and sound-absorbing cotton and preparation method thereof

Abstract

This invention discloses a lightweight and durable sound-insulating wheel cover based on PET and sound-absorbing cotton, comprising a substrate, two composite fiber layers on both sides of the substrate, a bottom adhesive layer at the bottom of one of the composite fiber layers, a top adhesive layer at the top of the other composite fiber layer, a flame-retardant layer at the top of the top adhesive layer, and sound-absorbing cotton at the bottom of the bottom adhesive layer; the substrate is a composite steel material made of low-carbon steel and D6AC or H-11 ultra-high-strength steel; the process steps of this invention, by bending the substrate before processing, can promptly repair any cracks in the profile, thereby ensuring that the strength and rigidity of the substrate are not affected, so that the substrate meets the requirements of lightweighting while also meeting its own performance requirements, further improving the service life of the automotive wheel cover.

Description

Technical Field

[0001] This invention relates to the field of automotive wheel cover technology, specifically to a lightweight and durable sound-insulating wheel cover based on PET and sound-absorbing cotton, and its preparation method. Background Technology

[0002] Wheel arch protectors are exterior trim pieces installed above the wheels. Their main function is to prevent rainwater or mud from adhering and soiling the car body, as well as to protect the body from damage caused by flying stones during driving. Previously, wheel arch protectors primarily focused on the rigidity of the car body to prevent soiling, often using vacuum-formed and injection-molded PE materials. These materials produced wheel arch protectors with good rigidity and a smooth surface. However, in practical applications, these wheel arch protectors have limited absorption of noise generated during driving, and when impacted by rainwater, mud, or stones, they produce impact noise that travels through the car body into the cabin, severely affecting the quietness of the interior.

[0003] Currently, there are four main types of materials used for wheel arch protectors in automotive exteriors: high-density polyethylene (HDPE), ethylene propylene diene monomer (PP) + EPDM (polypropylene + polypropylene), polypropylene and polyester fiber composites (PP + PET), and polyester fiber composites (PET + PET). PP + EPDM wheel arch protectors are currently the most common in the market. Polypropylene and polyester fiber composites (PP + PET) use polypropylene fibers as the matrix fiber and polyester fibers as the reinforcing fiber. A special process is used to uniformly mix and bundle the polyester and polypropylene fibers together. The two types of fibers in the composite fiber can be dispersed very evenly.

[0004] Currently, most car wheel covers on the market are heavy. High-performance polybutylene terephthalate (PET) is widely used in the production of car wheel covers because it can significantly reduce the weight of metal parts. However, car wheel covers made of traditional PET injection molding will have reduced performance when working in high-temperature environments, and their wear resistance and impact resistance are also poor.

[0005] Based on this, this application proposes a durable soundproof wheel cover that not only has sound absorption and vibration reduction functions, but also has a lightweight effect. Summary of the Invention

[0006] To address the aforementioned technical problems, this invention provides a lightweight and durable sound-insulating wheel cover based on PET and sound-absorbing cotton, as well as a method for its preparation.

[0007] The technical solution of the present invention is: a lightweight and durable sound insulation wheel cover based on PET and sound-absorbing cotton, characterized in that it includes a substrate, two composite fiber layers disposed on both sides of the substrate, a bottom adhesive layer disposed at the bottom of one of the composite fiber layers, a top adhesive layer disposed at the top of the other composite fiber layer, a flame retardant layer disposed at the top of the top adhesive layer, and sound-absorbing cotton disposed at the bottom of the bottom adhesive layer.

[0008] The material of the substrate is steel;

[0009] The composite fiber layer comprises, by weight, the following components: modified PET fiber: 60-70 parts; glass fiber: 10-20 parts; polypropylene fiber: 10-15 parts; PP fiber: 5-7 parts; the bottom adhesive layer and the top adhesive layer are coated with the same adhesive, with a coating thickness of 0.1-0.2 mm. The adhesive comprises, by weight, the following components: base adhesive: 40-60 parts; tackifier: 3-5 parts; crosslinking agent: 10-15 parts; anti-dripping agent: 10-15 parts; the flame retardant layer comprises, by weight, the following components: maleic acid resin: 30-45 parts; flame retardant: 3-5 parts.

[0010] Note: The composite fiber layer has excellent physical, chemical and acoustic properties. Glass fiber has good insulation, strong heat resistance, good corrosion resistance and high mechanical strength. Polypropylene fiber has impact resistance, waterproof and heat insulation properties. The composite fiber prepared by the composite fiber preparation method proposed in this invention has better heat insulation, durability and acoustic stability. After the substrate is encapsulated, it can significantly reduce the noise inside the vehicle. It also has the advantages of being lightweight and environmentally friendly.

[0011] Furthermore, the method for preparing the modified PET fiber includes the following steps:

[0012] 1) Preparation of modifier

[0013] Weigh out 10-15g of aerosol powder, ethylene glycol, and acrylate respectively in a weight ratio of 5-10:12-17:50-55 and place them in a beaker. Add 30-50mL of deionized water to the beaker, adjust the temperature to 70-80℃ and stir with a glass rod for 15-20min until well mixed to obtain the modifier.

[0014] 2) Preparation of the mixture

[0015] Pour half of the modifier prepared in step 1) into a three-necked flask and 5-10 mL of phthalic acid, and stir for 25-30 min to obtain mixture 1; then take the remaining half of the modifier and mix it with 5-10 mL of glycidyl methacrylate and stir for 15-20 min to obtain mixture 2; then mix mixture 1 and mixture 2 at a volume ratio of 1:1 and continue stirring for 3-5 min to obtain a modified emulsion;

[0016] 3) Immersion modification

[0017] The polyester fabric is immersed in the modified emulsion obtained in step S2 for 10-15 minutes, then removed and squeezed 2-3 times with an extruder at an extrusion intensity of 1.25-1.5 cm / min. Then it is placed in a drying oven and dried at 80-90℃ for 1.5-3 hours. Finally, it is removed to obtain modified PET fiber.

[0018] Note: Immersing polyester fabrics in modified emulsion can effectively improve the abrasion resistance of PET fibers. Through the modification treatment of PET fibers, glycidyl methacrylate can achieve curing through the cross-linking reaction between oxygen-containing groups and amine or carboxyl groups, which can effectively improve the film-forming performance of the modifier, thereby accelerating the film-forming rate on the surface of polyester fabrics and improving the manufacturing efficiency of PET fibers.

[0019] Further, by weight percentage, the base material comprises 25-40% low-carbon steel and 60-75% D6AC or H-11 ultra-high-strength steel; wherein the D6AC or H-11 ultra-high-strength steel is located at the wheel arch flange, and the low-carbon steel is located at the wheel arch web.

[0020] Note: The steel made by mixing low-carbon steel with D6AC or H-11 ultra-high-strength steel in the above proportion can effectively reduce the weight of the base material while meeting the basic strength and stiffness requirements of the wheel cover, making the base material lighter.

[0021] Furthermore, the base adhesive is selected from either silica or silica sol; the tackifier is selected from titanate coupling agents; the crosslinking agent is selected from silane coupling agents; and the anti-dripping agent is selected from polytetrafluoroethylene.

[0022] Note: Silica and silica sol are excellent binders that can dehydrate upon heating and evaporation, thus adhering to the surface of objects. Silica sol also possesses strong wear resistance, effectively extending the service life of automotive wheel covers. Titanate coupling agents effectively improve the dispersibility of the base adhesive and enhance the product's wear resistance. Silane coupling agents improve the bonding effect of the binder and can easily combine with glass fibers and resins, resulting in better adhesion. Polytetrafluoroethylene (PTFE) has superior anti-dripping properties, effectively improving the bonding effect of the binder.

[0023] A method for preparing a lightweight and durable sound-insulating wheel cover based on PET and sound-absorbing cotton includes the following steps:

[0024] S1. Preprocessing:

[0025] S1-1: Substrate treatment: Prepare a bending die and heat it to 490-510℃. Extruders extrude the substrate at a speed of 5-7 m / min for 3-5 min. After slow cooling, demold the substrate to obtain bent steel. The slow cooling rate is 0.03℃ / s-0.07℃ / s.

[0026] S1-2: Preparation of composite fiber layer: Take half of the modified PET fiber, half of the PP fiber, and half of the glass fiber according to the weight ratio and put them into a mixing box for mixing; then put the mixed fiber into an opening machine for opening, and add all the polypropylene fiber to the mixed fiber after opening treatment for secondary mixing; put the fiber after secondary mixing into a carding machine for carding; after carding, continue to add half of the modified PET fiber, half of the PP fiber, and half of the glass fiber to the carded fiber in sequence, put it into a mixing box for mixing again, and then send the mixed fiber into a web laying machine to lay a multi-layer fiber web. After the web laying is completed, send the multi-layer fiber web into a needle punching machine for needle punching processing, take it out and put it into an oven, and bake it at 170-180℃ for 20-30 minutes to obtain a composite fiber layer;

[0027] S1-3: Preparation of adhesive: Weigh the base adhesive, tackifier, crosslinking agent and anti-dripping agent according to the weight proportions mentioned above and stir until well mixed;

[0028] S2, Bonding of composite fiber layers

[0029] The composite fiber layer prepared in step S1-2 is effectively bonded to the surface of the bent steel material using a hot stamping composite machine to obtain a preliminary-formed car wheel cover; wherein the bonding temperature is 150-170℃.

[0030] S3, Apply adhesive layer

[0031] Weigh out 10-15% of catalyst powder, 50-70% of binder and the balance of water, and stir to obtain a mixed binder liquid. Immerse the car outer wheel cover prepared by S2 into the mixed binder liquid. Use ultrasound to ultrasonically treat the car outer wheel cover and the mixed binder liquid for 15-20 minutes. After taking it out, let it stand for 3-5 minutes.

[0032] S4, Flame-retardant coating, composite sound-absorbing cotton

[0033] Weigh the corresponding maleic acid resin and flame retardant according to the specified weight proportions, mix them evenly, and then apply them to the upper surface of the product obtained in step S3 to obtain a flame-retardant car wheel cover; effectively bond the sound-absorbing cotton and the lower surface of the flame-retardant car wheel cover together using a hot stamping composite machine to obtain a molded car wheel cover, and dry it at a temperature of 130-140℃ for 5-10 minutes, and then use nitrogen to blow the surface of the bent steel for 3-5 minutes;

[0034] S5, Embossing treatment

[0035] A lightweight and durable sound-insulating wheel cover based on PET and sound-absorbing cotton is obtained by embossing the front of the product using an embossing machine.

[0036] Explanation: The above manufacturing process allows the components to interact, resulting in a lightweight and durable sound-insulating wheel cover based on PET and sound-absorbing cotton with superior performance. By mixing modified PET fiber, glass fiber, polypropylene fiber, and PP fiber in batches according to the above proportions, the batch mixing of glass fiber ensures a more uniform distribution, effectively improving the insulation, heat resistance, and corrosion resistance of the composite fiber. The addition of polypropylene fiber gives the composite fiber impact resistance, waterproof and heat insulation properties, which helps improve the sound absorption performance of the composite fiber while also providing waterproof and flame-retardant effects. Bending the substrate before processing allows for the repair of cracks in the profile. The repair method involves melting high-strength steel profiles and coating them onto the cracks in the bent steel, ensuring that the strength and rigidity of the substrate are not affected, further extending the service life of the wheel cover.

[0037] Furthermore, in step S1-1, the slow cooling treatment method is: cooling to room temperature using water cooling method;

[0038] Note: Water cooling can improve the toughness of bent steel.

[0039] Further, in steps S1-2, the needle-punching process is as follows: using 230-250 needles / cm 2 The initial acupuncture density was used for acupuncture, followed by rinsing in room temperature water for 3-5 minutes, drying, and then a second acupuncture session. The acupuncture density was 30-60 needles / cm². 2 To reduce the severity, the number of acupuncture sessions should be 2-4.

[0040] Note: The needle punching process described above can effectively improve the composite degree between the fibers and the porosity of the composite fiber layer, thereby making the wheel cover lighter.

[0041] Furthermore, in step S3, the catalyst powder is selected from magnesium hydroxide powder;

[0042] Note: Magnesium hydroxide powder has good buffering and adsorption properties, and it is also a reactant for the resin. It can effectively improve the adhesion of the adhesive while also having a good heat absorption and cooling effect, further improving the flame retardant effect of the wheel cover.

[0043] Further, in step S3, the ultrasonic wave parameters are: power density: 0.25~0.35W / cm². 2 ;

[0044] Note: Within the above power density range, the mixing degree between the automotive outer wheel cover and the mixed adhesive can be improved. When the ultrasonic power density is greater than 0.35 W / cm², the mixing degree can be improved. 2 This will generate greater pressure in the liquid, which can easily damage the surface of the bent steel and affect the production efficiency of the car wheel cover.

[0045] The beneficial effects of this invention are:

[0046] (1) By bending the substrate first and then processing it, the present invention can facilitate timely repair of the cracked profile, thereby ensuring that the strength and rigidity of the substrate are not affected, so that the substrate can meet the requirements of lightweighting while meeting its own performance requirements, and further improve the service life of the car wheel cover.

[0047] (2) This invention can effectively improve the abrasion resistance of PET fibers by immersing polyester fabrics in modified emulsions. By preparing a modifier containing glycidyl methacrylate, the film-forming performance of the modifier can be effectively improved, thereby accelerating the film-forming rate on the surface of polyester fabrics. The curing effect is achieved through the cross-linking reaction between oxygen-containing groups and amine or carboxyl groups, which can effectively improve the film-forming rate of the modifier, making the film-forming dispersion on the surface of polyester fabrics more uniform and effectively improving the abrasion resistance of composite fibers. On the other hand, the performance of the sound insulation wheel cover is improved by increasing the tensile strength and impact strength of composite fibers.

[0048] (3) The lightweight and durable soundproof wheel cover based on PET and sound-absorbing cotton prepared by the present invention has better performance; by mixing and compounding modified PET fiber, glass fiber, polypropylene fiber and PP fiber in batches in a certain proportion, the glass fiber can be mixed in batches to make the glass fiber distribution more uniform, thereby effectively improving the insulation, heat resistance and corrosion resistance of the composite fiber. The addition of polypropylene fiber makes the composite fiber impact resistant, waterproof and heat-insulating, so that the composite fiber has waterproof and flame-retardant functions while improving sound absorption and lightweight performance. Attached Figure Description

[0049] Figure 1 This is a structural schematic diagram of an embodiment of the present invention.

[0050] Among them, 1-substrate, 2-composite fiber layer, 3-bottom adhesive layer, 4-top adhesive layer, 5-flame retardant layer, and 6-sound absorbing cotton. Detailed Implementation

[0051] The present invention will now be described in more detail with reference to specific embodiments, so as to better demonstrate the advantages of the present invention.

[0052] Example 1

[0053] A lightweight and durable soundproof wheel cover based on PET and sound-absorbing cotton includes a substrate 1, two composite fiber layers 2 disposed on both sides of the substrate 1, a bottom adhesive layer 3 disposed at the bottom of one of the composite fiber layers 2, a top adhesive layer 4 disposed at the top of the other composite fiber layer 2, a flame retardant layer 5 disposed at the top of the top adhesive layer 4, and sound-absorbing cotton 6 disposed at the bottom of the bottom adhesive layer 3.

[0054] The material of substrate 1 is steel; by mass percentage, substrate 1 comprises 30% low carbon steel and 70% D6AC or H-11 ultra-high strength steel.

[0055] The composite fiber layer 2, by weight, comprises the following components: modified PET fiber: 65 parts; glass fiber: 15 parts; polypropylene fiber: 12 parts; PP fiber: 6 parts; the bottom adhesive layer 3 and the top adhesive layer 4 are coated with the same adhesive, with a coating thickness of 0.15 mm. The adhesive, by weight, comprises the following components: base adhesive: 50 parts; tackifier: 4 parts; crosslinking agent: 13 parts; anti-dripping agent: 13 parts; the flame retardant layer 5, by weight, comprises the following components: maleic acid resin: 35 parts; flame retardant: 4 parts; wherein, the base adhesive is silica sol; the tackifier is titanate coupling agent; the crosslinking agent is silane coupling agent; and the anti-dripping agent is polytetrafluoroethylene.

[0056] The preparation method of modified PET fibers includes the following steps:

[0057] 1) Preparation of modifier

[0058] Weigh out 12g each of aerosol powder, ethylene glycol, and acrylate in a weight ratio of 8:15:52 and place them in a beaker. Add 40mL of deionized water to the beaker, adjust the temperature to 75℃ and stir with a glass rod for 18 minutes to obtain the modifier.

[0059] 2) Preparation of the mixture

[0060] Pour half of the modifier prepared in step 1 and 7 mL of phthalic acid into a three-necked flask, stir for 28 min to obtain mixture 1; then take the remaining half of the modifier and mix it with 7 mL of glycidyl methacrylate and stir for 18 min to obtain mixture 2; then mix mixture 1 and mixture 2 at a volume ratio of 1:1 and continue stirring for 4 min to obtain the modified emulsion;

[0061] 3) Immersion modification

[0062] The polyester fabric was immersed in the modified emulsion obtained in step S2 for 12 minutes, then removed and squeezed twice with an extruder at an extrusion intensity of 1.35 cm / min. Then it was placed in a drying oven and dried at 85℃ for 2 hours. Finally, it was removed to obtain modified PET fiber.

[0063] The method for preparing a lightweight and durable sound-insulating wheel cover based on PET and sound-absorbing cotton includes the following steps:

[0064] S1. Preprocessing:

[0065] S1-1: Substrate 1 treatment: Prepare a bending die and heat it to 500℃. Extruders extrude the substrate 1 at an extrusion speed of 6m / min for 4min. After slow cooling, demold to obtain bent steel. The slow cooling rate is 0.05℃ / s. The slow cooling method is to cool it to room temperature by water cooling.

[0066] S1-2: Preparation of composite fiber layer 2: Half of the modified PET fiber, half of the PP fiber, and half of the glass fiber as described in claim 1 are mixed in a mixing box according to the weight proportions. Then, the mixed fibers are placed in an opening machine for opening. All the polypropylene fiber is added to the mixed fibers after the opening treatment for secondary mixing. The fibers after secondary mixing are placed in a carding machine for carding. After carding, half of the modified PET fiber, half of the PP fiber, and half of the glass fiber are added to the carded fibers in sequence. The fibers are placed in a mixing box for mixing again. Then, the mixed fibers are sent to a web laying machine to lay a multi-layer fiber web. After the web laying is completed, the multi-layer fiber web is sent to a needle punching machine for needle punching treatment. After taking it out, it is placed in an oven and baked at 175°C for 25 minutes to obtain the composite fiber layer. The needle punching treatment process is as follows: using 240 needles / cm 2 The initial acupuncture density was used for acupuncture, followed by rinsing in room temperature water for 4 minutes, drying, and then a second acupuncture session. The acupuncture density was 50 needles / cm². 2 The acupuncture frequency was reduced to 3 times.

[0067] S1-3: Preparation of adhesive: Weigh the base adhesive, tackifier, crosslinking agent and anti-dripping agent according to the stated weight proportions and stir until well mixed;

[0068] Bonding of S2 and composite fiber layer 2

[0069] The composite fiber layer 2 prepared in step S1-2 is effectively bonded to the surface of the bent steel material using a hot stamping composite machine to obtain a preliminary-formed car wheel cover; wherein the bonding temperature is 160℃.

[0070] S3, Apply adhesive layer

[0071] 12% (by mass) of catalyst powder, 60% of binder, and the remainder water were weighed and mixed to obtain a mixed binder solution. The car outer wheel cover prepared in S2 was immersed in the mixed binder solution, and the car outer wheel cover and the mixed binder solution were ultrasonically treated for 18 minutes. After removal, it was allowed to stand for 4 minutes. The catalyst powder used was magnesium hydroxide powder. The ultrasonic treatment parameters were: power density: 0.30 W / cm³. 2 ;

[0072] S4, Flame-retardant coating; 5, Composite sound-absorbing cotton; 6.

[0073] Weigh the corresponding maleic acid resin and flame retardant according to the specified weight proportions, mix them evenly, and then apply them to the upper surface of the product obtained in step S3 to obtain a flame-retardant car wheel cover; effectively bond the sound-absorbing cotton 6 to the lower surface of the flame-retardant car wheel cover using a hot stamping composite machine to obtain a molded car wheel cover, dry it at a temperature of 135°C for 8 minutes, and then use nitrogen to blow the surface of the bent steel for 4 minutes;

[0074] S5, Embossing treatment

[0075] The product's front surface is embossed using an embossing machine to obtain a lightweight and durable sound-insulating wheel cover based on PET and sound-absorbing cotton.

[0076] Example 2

[0077] Unlike Example 1, the composite fiber layer 2, by weight, comprises the following components: modified PET fiber: 60 parts; glass fiber: 10 parts; polypropylene fiber: 10 parts; PP fiber: 5 parts; the adhesive, by weight, comprises the following components: base adhesive: 40 parts; tackifier: 3 parts; crosslinking agent: 10 parts; anti-dripping agent: 10 parts; and the flame retardant layer 5, by weight, comprises the following components: maleic acid resin: 30 parts; flame retardant: 3 parts.

[0078] Example 3

[0079] Unlike Example 1, the composite fiber layer 2, by weight, comprises the following components: modified PET fiber: 70 parts; glass fiber: 20 parts; polypropylene fiber: 15 parts; PP fiber: 7 parts; the adhesive, by weight, comprises the following components: base adhesive: 60 parts; tackifier: 5 parts; crosslinking agent: 15 parts; anti-dripping agent: 15 parts; and the flame retardant layer 5, by weight, comprises the following components: maleic acid resin: 45 parts; flame retardant: 5 parts.

[0080] Example 4

[0081] Unlike Example 1, the method for preparing modified PET fibers includes the following steps:

[0082] 1) Preparation of modifier

[0083] Weigh out 12g each of aerosol powder, ethylene glycol, and acrylate in a mass ratio of 5:12:50 and place them in a beaker.

[0084] Example 5

[0085] Unlike Example 1, the method for preparing modified PET fibers includes the following steps:

[0086] 1) Preparation of modifier

[0087] Weigh out 12g each of aerosol powder, ethylene glycol, and acrylate in a mass ratio of 10:17:55 and place them in a beaker.

[0088] Example 6

[0089] Unlike Example 1, the method for preparing modified PET fibers includes the following steps:

[0090] 2) Preparation of the mixture

[0091] Pour half of the modifier prepared in step 1 and 5 mL of phthalic acid into a three-necked flask and stir for 25 min to obtain mixture 1; then take the remaining half of the modifier and mix it with 5 mL of glycidyl methacrylate and stir for 15 min to obtain mixture 2; then mix mixture 1 and mixture 2 at a volume ratio of 1:1 and continue stirring for 3 min to obtain the modified emulsion.

[0092] Example 7

[0093] Unlike Example 1, the method for preparing modified PET fibers includes the following steps:

[0094] 2) Preparation of the mixture

[0095] Pour half of the modifier prepared in step 1 and 10 mL of phthalic acid into a three-necked flask and stir for 30 min to obtain mixture 1; then take the remaining half of the modifier and mix it with 10 mL of glycidyl methacrylate and stir for 20 min to obtain mixture 2; then mix mixture 1 and mixture 2 at a volume ratio of 1:1 and continue stirring for 5 min to obtain the modified emulsion.

[0096] Example 8

[0097] Unlike Example 1, the method for preparing modified PET fibers includes the following steps:

[0098] 3) Immersion modification

[0099] The polyester fabric is immersed in the modified emulsion obtained in step S2 for 10 minutes, then removed and squeezed twice with an extruder at an extrusion intensity of 1.5 cm / min. Then it is placed in a drying oven and dried at 80℃ for 1.5 hours. Finally, it is removed to obtain modified PET fiber.

[0100] Example 9

[0101] Unlike Example 1, the method for preparing modified PET fibers includes the following steps:

[0102] 3) Immersion modification

[0103] The polyester fabric was immersed in the modified emulsion obtained in step S2 for 15 minutes, then removed and squeezed 3 times with an extruder at an extrusion intensity of 1.25 cm / min. Then it was placed in a drying oven and dried at 90℃ for 3 hours. Finally, it was removed to obtain modified PET fiber.

[0104] Example 10

[0105] Unlike Example 1, in step S1 of the method for preparing a lightweight and durable sound-insulating wheel cover based on PET and sound-absorbing cotton,

[0106] S1-1: Substrate 1 treatment: Prepare a bending die and heat it to 490℃. Extruders extrude the substrate 1 at an extrusion speed of 5m / min for 5min. After slow cooling treatment, demold to obtain bent steel. The slow cooling rate is 0.03℃ / s.

[0107] Example 11

[0108] Unlike Example 1, in step S1 of the method for preparing a lightweight and durable sound-insulating wheel cover based on PET and sound-absorbing cotton,

[0109] S1-1: Substrate 1 treatment: Prepare a bending die and heat it to 510℃. Extruders extrude the substrate 1 at an extrusion speed of 7m / min for 3min. After slow cooling, demold to obtain bent steel. The slow cooling rate is 0.07℃ / s.

[0110] Example 12

[0111] Unlike Example 1, in step S1 of the method for preparing a lightweight and durable sound-insulating wheel cover based on PET and sound-absorbing cotton,

[0112] S1-2: Preparation of composite fiber layer 2: After the web is laid, the multi-layer fiber web is sent to a needle punching machine for needle punching. After being taken out, it is placed in an oven and baked at 170℃ for 20 minutes to obtain the composite fiber layer.

[0113] Example 13

[0114] Unlike Example 1, in step S1 of the method for preparing a lightweight and durable sound-insulating wheel cover based on PET and sound-absorbing cotton,

[0115] S1-2: Preparation of composite fiber layer 2: After the web is laid, the multi-layer fiber web is sent to a needle punching machine for needle punching. After being taken out, it is placed in an oven and baked at 180°C for 30 minutes to obtain the composite fiber layer.

[0116] Example 14

[0117] Unlike Example 1, in steps S1-2, the needle-punching process is as follows: using 230 needles / cm 2 The initial acupuncture density was used for acupuncture, followed by rinsing in room temperature water for 3 minutes, and then drying; then a second acupuncture was performed; the acupuncture density was 30 needles / cm. 2 The number of acupuncture sessions was reduced to 2.

[0118] Example 15

[0119] Unlike Example 1, in steps S1-2, the needle-punching process is as follows: using 250 needles / cm 2 The initial acupuncture density was used for acupuncture, followed by rinsing in room temperature water for 5 minutes, and then drying; then a second acupuncture was performed; the acupuncture density was 60 needles / cm. 2 The number of acupuncture sessions was reduced to 4.

[0120] Example 16

[0121] Unlike Example 1, in step S3, 10% of the catalyst powder, 50% of the binder and the remainder water were weighed and mixed to obtain a mixed binder liquid. The car wheel cover prepared in S2 was immersed in the mixed binder liquid. The car wheel cover and the mixed binder liquid were ultrasonically treated with ultrasound for 15 minutes. After being taken out, it was left to stand for 3 minutes.

[0122] Example 17

[0123] Unlike Example 1, in step S3, 15% of the catalyst powder, 70% of the binder and the remainder water were weighed and mixed to obtain a mixed binder liquid. The car wheel cover prepared in S2 was immersed in the mixed binder liquid. The car wheel cover and the mixed binder liquid were ultrasonically treated with ultrasound for 20 minutes. After being taken out, it was left to stand for 5 minutes.

[0124] Example 18

[0125] Unlike Example 1, in step S4, the surface of the bent steel is purged with nitrogen for 3 minutes and then dried at 130°C for 5 minutes.

[0126] Example 19

[0127] Unlike Example 1, in step S4, the surface of the bent steel is purged with nitrogen for 5 minutes and then dried at 140°C for 10 minutes.

[0128] Example for comparison:

[0129] Compare with Example 1

[0130] Unlike Example 1,

[0131] Pour the modifier prepared in step 1 and 7 mL of phthalic acid into a three-necked flask in sequence, stir for 28 min, and the resulting mixture 1 is the modified emulsion.

[0132] Compare with Example 2

[0133] Unlike Example 1, the modified emulsion obtained in step S2 was sprayed onto the surface of the polyester fabric through a spray bottle, then placed in a drying oven and dried at 85°C for 2 hours. Finally, it was taken out to obtain modified PET fibers.

[0134] Compare with Example 3

[0135] Unlike Example 1, the substrate 1 is made of low-carbon steel.

[0136] Compare with Example 4

[0137] Unlike Example 1, no substrate treatment is performed in step S1, and the substrate treatment is performed after step S4.

[0138] Compare with Example 5

[0139] Unlike Example 1, no secondary acupuncture treatment was performed.

[0140] Experimental example:

[0141] Three test pieces with a diameter of approximately 150 mm were cut from each of the soundproof wheel cover samples prepared in Examples 1 to 19 and Comparative Examples 1 to 4, respectively. Various properties of the test pieces were tested. The test pieces were placed in a constant temperature bath at 100°C for 3 hours to check the expansion rate and shrinkage rate. The test pieces were abraded with a force of 2.5 N for 200 revolutions, and the surface condition was represented by a friction level (where level 2 represents significant contamination, level 3 represents visible but rarely noticeable contamination, level 4 represents slightly visible but almost inconspicuous contamination, and level 5 represents no abnormality at all). The average value was taken as a reference. The test results are as follows:

[0142] 1. Investigate the effects of different raw material ratios on the performance of the soundproof wheel cover.

[0143] Table 1. Performance test table of the soundproof wheel covers prepared in Examples 1-3, Examples 6-7, and Comparative Examples 1-3.

[0144]

[0145] Conclusion: The performance test results of Examples 1-3, Examples 6 and 7, and Comparative Example 1 in Table 1 show that adding glycidyl methacrylate to the modified solution effectively improves the tensile strength and impact resistance of the soundproof wheel cover. This is because, through the modification of PET fibers, glycidyl methacrylate can achieve curing through cross-linking reactions between oxygen-containing groups and amine or carboxyl groups, effectively improving the film-forming performance of the modifier. This results in a more uniform film dispersion on the polyester fabric surface, effectively improving the wear resistance of the composite fiber. On the other hand, by increasing the tensile strength and impact resistance of the composite fiber, the performance of the soundproof wheel cover is improved. While spraying the polyester fabric in Comparative Example 2 effectively reduces the weight of the soundproof wheel cover, it also reduces its wear resistance. Although using high-strength steel in Comparative Example 3 significantly reduces the weight of the soundproof wheel cover, it also significantly weakens its impact resistance. Therefore, considering all performance aspects, Example 1 is the optimal solution.

[0146] 2. Investigate the influence of processing sequence on various performance characteristics of the soundproof wheel cover.

[0147] Table 2 Performance test table of the soundproof wheel covers prepared in Examples 1, 10-11 and Comparative Example 4

[0148]

[0149] Conclusion: As shown in Table 2, bending the substrate before processing allows for adjustments and repairs to address profile cracking, ensuring the strength and rigidity of the substrate remain unaffected and further extending the service life of the wheel arch. In contrast, bending the substrate after step S4 and before S5 in Comparative Example 4 fails to guarantee the rigidity and strength of the wheel arch substrate, thus reducing the service life of the wheel arch. Therefore, the soundproof wheel arch prepared using the proposed method is more durable.

[0150] 3. Investigate the impact of needle punching process on the performance of automobile wheel arches.

[0151] Table 3. Performance test table of the soundproof wheel covers prepared in Examples 1, 14-15, and Comparative Example 5.

[0152]

[0153] Conclusion: As shown in Table 3, the needle punching process in Examples 1, 14, and 15 can effectively improve the composite degree between the fibers, with Example 1 showing the best effect. Simultaneously, the needle punching process can effectively increase the porosity of the composite fiber layer, thus making the wheel cover lighter. However, as shown in Comparative Example 5, without secondary needle punching, the composite degree between the fiber layers weakens, leading to a decline in all performance characteristics. This also confirms that the needle punching process provided by this invention has a superior effect on improving the performance of automotive wheel covers.

Claims

1. A lightweight and durable sound-insulating wheel cover based on PET and sound-absorbing cotton, characterized in that, It includes a substrate (1), two composite fiber layers (2) disposed on both sides of the substrate (1), a bottom adhesive layer (3) disposed at the bottom of one of the composite fiber layers (2), a top adhesive layer (4) disposed at the top of the other composite fiber layer (2), a flame retardant layer (5) disposed at the top of the top adhesive layer (4), and a sound-absorbing cotton (6) disposed at the bottom of the bottom adhesive layer (3). The material of the substrate (1) is steel; The composite fiber layer (2) comprises the following components by weight: modified PET fiber: 60-70 parts; glass fiber: 10-20 parts; Polypropylene fiber: 10-15 parts; PP fiber: 5-7 parts; The bottom adhesive layer (3) and the top adhesive layer (4) are coated with the same adhesive, with a coating thickness of 0.1~0.2mm. The adhesive, by weight, includes the following components: base adhesive: 40~60 parts; Tackifier: 3-5 parts; Crosslinking agent: 10-15 parts; Anti-dripping agent: 10-15 parts; The flame retardant layer (5) comprises the following components by weight: maleic acid resin: 30-45 parts; flame retardant: 3-5 parts; The preparation method of the modified PET fiber includes the following steps: 1) Preparation of modifier Weigh out 10-15g of aerosol powder, ethylene glycol, and acrylate in a mass ratio of 5-10:12-17:50-55 and place them in a beaker. Add 30-50mL of deionized water to the beaker, adjust the temperature to 70-80℃ and stir with a glass rod for 15-20 minutes until well mixed to obtain the modifier. 2) Preparation of the mixture Pour half of the modifier prepared in step 1) into a three-necked flask and 5-10 mL of phthalic acid, and stir for 25-30 min to obtain mixture 1; then take the remaining half of the modifier and mix it with 5-10 mL of glycidyl methacrylate and stir for 15-20 min to obtain mixture 2; then mix mixture 1 and mixture 2 at a volume ratio of 1:1 and continue stirring for 3-5 min to obtain the modified emulsion; 3) Immersion modification The polyester fabric is immersed in the modified emulsion obtained in step S2 for 10-15 minutes, then removed and squeezed 2-3 times with an extruder at an extrusion intensity of 1.25-1.5 cm / min. Then it is placed in a drying oven and dried at 80-90℃ for 1.5-3 hours. Finally, it is removed to obtain modified PET fiber. The substrate (1) comprises 25-40% low carbon steel and 60-75% D6AC or H-11 ultra-high strength steel. The base adhesive is selected from either silica or silica sol; the tackifier is selected from titanate coupling agents; the crosslinking agent is selected from silane coupling agents; and the anti-dripping agent is selected from polytetrafluoroethylene.

2. The method for preparing a lightweight and durable sound-insulating wheel cover based on PET and sound-absorbing cotton according to claim 1, characterized in that, Includes the following steps: S1. Preprocessing: S1-1: Substrate (1) treatment: Prepare a bending die and heat it to 490~510℃. Extruder extrudes the substrate (1) at an extrusion speed of 5~7m / min for 3~5min. Slow cooling treatment, demolding, and obtain bent steel; wherein, the slow cooling speed is 0.03℃ / s~0.07℃ / s. S1-2: Preparation of composite fiber layer (2): Take half of the modified PET fiber, half of the PP fiber and half of the glass fiber according to the weight ratio and put them into the mixing box for mixing; then put the mixed fiber into the opening machine for opening, add all the polypropylene fiber to the mixed fiber after opening treatment for secondary mixing; put the fiber after secondary mixing into the carding machine for carding; after carding, continue to add half of the modified PET fiber, half of the PP fiber and half of the glass fiber to the carded fiber in sequence, put it into the mixing box for mixing again, and then send the mixed fiber into the web laying machine to lay a multi-layer fiber web. After the web laying is completed, send the multi-layer fiber web into the needle punching machine for needle punching treatment, take it out and put it into the oven, bake at 170~180℃ for 20~30min to obtain the composite fiber layer; S1-3: Preparation of adhesive: Weigh the base adhesive, tackifier, crosslinking agent and anti-dripping agent according to the weight proportions mentioned above and stir until well mixed; S2, Bonding of composite fiber layer (2) The composite fiber layer (2) prepared in step S1-2 is effectively bonded to the surface of the bent steel material using a hot stamping composite machine to obtain a preliminary-formed car wheel cover; wherein the bonding temperature is 150~170℃. S3, Apply adhesive layer Weigh out 10-15% of catalyst powder, 50-70% of binder and the balance of water, and stir to obtain a mixed binder liquid. Immerse the car outer wheel cover prepared by S2 into the mixed binder liquid. Use ultrasound to ultrasonically treat the car outer wheel cover and the mixed binder liquid for 15-20 minutes. After taking it out, let it stand for 3-5 minutes. S4, Flame-retardant coating (5), Composite sound-absorbing cotton (6) Weigh the corresponding maleic acid resin and flame retardant according to the weight proportions, mix them evenly, and then apply them to the upper surface of the product obtained in step S3 to obtain a flame-retardant car wheel cover; effectively bond the sound-absorbing cotton (6) to the lower surface of the flame-retardant car wheel cover using a hot heat bonding machine to obtain a molded car wheel cover, and dry it at a temperature of 130~140℃ for 5~10 minutes, and then use nitrogen to blow the surface of the bent steel for 3~5 minutes; S5, Embossing treatment The product's front surface is embossed using an embossing machine to obtain a lightweight and durable sound-insulating wheel cover based on PET and sound-absorbing cotton.

3. The method for preparing a lightweight and durable sound-insulating wheel cover based on PET and sound-absorbing cotton according to claim 2, characterized in that, In step S1-1, the slow cooling method is to cool the room temperature using water cooling.

4. The method for preparing a lightweight and durable sound-insulating wheel cover based on PET and sound-absorbing cotton according to claim 2, characterized in that, In steps S1-2, the needle-punching process is as follows: using 230~250 needles / cm 2 The initial acupuncture density is used for acupuncture, followed by rinsing in room temperature water for 3-5 minutes, and then drying; then a second acupuncture is performed; wherein the acupuncture density is 30-60 needles / cm. 2 To reduce the severity, the number of acupuncture sessions should be 2-4.

5. The method for preparing a lightweight and durable sound-insulating wheel cover based on PET and sound-absorbing cotton according to claim 2, characterized in that, In step S3, the catalyst powder is selected from magnesium hydroxide powder.

6. The method for preparing a lightweight and durable sound-insulating wheel cover based on PET and sound-absorbing cotton according to claim 2, characterized in that, In step S3, the ultrasonic wave parameters are: power density: 0.25~0.35W / cm². 2 .

Images