High-performance automobile sound insulation and noise reduction damping sheet and preparation method thereof

Abstract

The application discloses a high-performance automobile sound insulation and noise reduction damping sheet and a preparation method thereof, and belongs to the technical field of damping sheets. The high-performance automobile sound insulation and noise reduction damping sheet comprises the following raw materials in mass fractions: butyl rubber: 10-20 parts; barium sulfate: 100-150 parts; polyisobutylene: 30-50 parts; silicon dioxide: 5-20 parts; carbon black: 0.1-1 part; anti-aging agent: 1-5 parts; and iron powder: 150-200 parts. The preparation method comprises the following steps: weighing the raw materials and mixing and pretreating; mixing; extruding into a sheet shape; calendering treatment for adjusting thickness and flatness; and cooling and solidifying. After the formula is optimized, the cost is reduced, the mixing and processing of the raw materials are more smooth, the loss and waste in the production process are reduced, the product has excellent vibration and noise reduction performance, and the product also has good heat resistance, cold resistance and anti-aging property, the performance limitation can be reduced, and the service life of the damping sheet is prolonged.

Description

Technical Field

[0001] This invention belongs to the field of damping sheet technology, and particularly relates to a high-performance automotive sound insulation and noise reduction damping sheet and its preparation method. Background Technology

[0002] With the rapid development of the automotive industry, the requirements for controlling interior noise and vibration in automobiles are becoming increasingly stringent. Damping sheets, as crucial components for noise reduction and vibration damping in automobiles, directly impact vehicle comfort and safety. High-performance automotive sound insulation and noise reduction damping sheets are widely used in vehicle sheet metal parts such as doors, trunk floors, and chassis. These components are prone to vibration and noise during vehicle operation. Damping sheets, through their high damping characteristics, can effectively reduce vibration and noise, thereby improving ride comfort. Therefore, developing a high-performance, environmentally friendly, and durable damping sheet is of great significance.

[0003] In the prior art, the method for preparing such a damping sheet typically includes the following steps: 1. Raw material preparation: The main raw materials include inorganic rubber fillers (such as talc, light calcium carbonate, heavy calcium carbonate, heavy barium sulfate, etc.), coupling agents, lubricants, antioxidants, etc. The ratio and quality of the raw materials have a significant impact on the performance of the damping sheet.

[0004] 2. Mixing: Add the weighed raw materials to the high-speed mixer and heat them to a certain temperature (e.g., 70°C) before mixing. The mixed material needs to be cooled to room temperature to ensure the smooth progress of the subsequent extrusion process.

[0005] 3. Extrusion: The mixed materials are fed into a twin-screw extruder. Through the rotation and extrusion action of the screws, the materials are extruded into continuous sheets. During the extrusion process, the temperature needs to be strictly controlled (e.g., barrel temperature 50-80℃, die head temperature 50-80℃) to ensure the quality and performance of the sheets.

[0006] 4. Forming: After cooling and shaping, the extruded sheet can be cut into the required shape and size; during the forming process, it is necessary to ensure the flatness and dimensional accuracy of the sheet.

[0007] 5. Post-processing: The molded damping sheet may require surface treatment, quality inspection and other follow-up work to ensure that the damping sheet meets the design requirements and quality standards.

[0008] The aforementioned prior art has the following drawbacks: (1) High cost: The raw materials used in the existing technology are expensive, which increases the manufacturing cost of the damping sheet. The production process of butyl rubber is complicated and the raw materials are scarce, which makes its price much higher than that of ordinary rubber and asphalt. The higher the rubber content in the damping sheet, the better its damping performance and shock absorption effect, but the cost also increases accordingly.

[0009] (2) Complex process: The preparation process involves multiple steps and links, and requires strict control of various parameters and conditions, making the process relatively complex.

[0010] (3) Performance limitations: Although the damping sheets prepared by existing technology have certain sound insulation and noise reduction performance, their performance may be limited under certain specific conditions (such as high temperature, high frequency vibration, etc.). Summary of the Invention

[0011] The purpose of this invention is to address the above-mentioned problems by providing a high-performance automotive sound insulation and noise reduction damping sheet.

[0012] Another objective of this invention is to provide a method for preparing a high-performance automotive sound insulation and noise reduction damping sheet, addressing the aforementioned problems.

[0013] To achieve the above objectives, the present invention adopts the following technical solutions: A high-performance automotive sound insulation and noise reduction damping sheet comprises 10-20 parts by weight of butyl rubber, 100-150 parts of barium sulfate, 30-50 parts of polyisobutylene, 5-20 parts of silica, 0.1-1 parts of carbon black, 1-5 parts of antioxidant, and 150-200 parts of iron powder.

[0014] The aforementioned high-performance automotive sound insulation and noise reduction damping sheet comprises 12-18 parts by weight of butyl rubber, 125-140 parts by weight of barium sulfate, 35-45 parts by weight of polyisobutylene, 7-12 parts by weight of silica, 0.3-0.8 parts by weight of carbon black, 2-4 parts by weight of anti-aging agent, and 160-190 parts by weight of iron powder.

[0015] A method for preparing a high-performance automotive sound insulation and noise reduction damping sheet includes the following steps: Step 1: Raw material preparation. After accurately weighing each component raw material according to the proportion, pre-treatment is carried out. Step 2: Mixing. Place the pretreated raw materials in an internal mixer and mix them to ensure that the various components are evenly dispersed and blended. Step 3: Extrusion. The uniformly mixed material is evenly fed into the extruder and extruded into thin sheets through the die. Step 4: Calendering. The extruded sheet material is fed into a three-roll calender for calendering to obtain the required thickness and flatness. Step 5: Cooling and curing. The calendered damping sheet is cooled to cure it and achieve the required physical properties.

[0016] In the above-mentioned method for preparing a high-performance automotive sound insulation and noise reduction damping sheet, the pretreatment in step one includes mixing and homogenizing the raw materials of each component: using an internal mixer for colloid pretreatment, and then using a kneader to add and mix the raw materials of each component.

[0017] In the above-mentioned method for preparing a high-performance automotive sound insulation and noise reduction damping sheet, the mixing temperature in step two is 90-150℃.

[0018] In the above-mentioned method for preparing a high-performance automotive sound insulation and noise reduction damping sheet, the extrusion temperature in step three is 50-90℃.

[0019] In the above-mentioned method for preparing a high-performance automotive sound insulation and noise reduction damping sheet, the calendering process in step four includes multiple calendering and trimming processes.

[0020] In the above-mentioned method for preparing a high-performance automotive sound insulation and noise reduction damping sheet, the cooling method in step five is natural cooling or forced cooling.

[0021] In the above-mentioned method for preparing a high-performance automotive sound insulation and noise reduction damping sheet, the iron powder is modified iron powder with a soft magnetic material coated on its surface.

[0022] In the above-mentioned method for preparing a high-performance automotive sound insulation and noise reduction damping sheet, the soft magnetic material is iron oxide (Fe3O4), which is coated onto the surface of iron powder using a liquid-phase chemical deposition method. Specifically, the liquid-phase chemical deposition method uses pure iron powder as the core, FeSO4·7H2O and FeCl3·6H2O as the coating materials, ammonia as the precipitant, and nitrogen to create an oxygen-free environment. The remaining operations follow the standard procedures of existing liquid-phase chemical deposition methods.

[0023] Compared with existing technologies, the advantages of this invention are: 1. This invention possesses excellent vibration reduction and noise reduction performance. The formulation of this invention utilizes high-damping materials such as butyl rubber. These materials can absorb and dissipate a large amount of vibration energy during vibration, thereby reducing the vibration amplitude and achieving a vibration reduction effect. Fillers such as barium sulfate, iron powder, and carbon black act as a skeleton and reinforcement in the damping sheet. They can increase the overall rigidity and strength of the damping sheet, and also help improve the damping performance of the damping sheet. In addition, these fillers generate friction with the rubber matrix during vibration, further consuming vibration energy and enhancing the vibration reduction effect. Viscous materials such as liquid polyisobutylene act as adhesives and thickeners in the damping sheet. They can ensure a tight fit between the damping sheet and the steel plate wall of the vehicle body, reduce vibration transmission, and further improve the vibration reduction and noise reduction performance of the damping sheet.

[0024] 2. The iron powder of this invention is modified by coating with iron(III) oxide. When the structure to which the damping sheet is attached vibrates, the damping sheet will undergo slight deformation, and the soft magnetic coated iron powder inside will also deform or be in a dynamic stress environment. Due to the diamagnetic effect, a weak and rapidly changing magnetic field will be indirectly induced inside the magnetic particles. Inside the soft magnetic material, there are many tiny regions called "magnetic domains". In each magnetic domain, all atomic magnetic moments are oriented in the same direction. When in an alternating magnetic field, these magnetic domains will try to adjust themselves to keep up with the changes in the magnetic field. During the adjustment process, due to the presence of impurities, lattice defects, internal stress, etc. inside the material, the magnetic domains will be hindered. Overcoming these resistances requires energy consumption and is eventually released in the form of heat. This causes some of the vibrational mechanical energy that should have been transmitted through the structure to be converted into changing magnetic field energy and then dissipated through heat, thereby further hindering vibration transmission and improving vibration reduction and noise reduction performance.

[0025] 3. This invention can reduce the vibration of the vehicle body's steel panels. The damping sheet, as a damping layer attached to the vehicle body's steel panels, can absorb and dissipate the energy generated by the vehicle body's vibration. When the vehicle body is subjected to external excitation (such as vibration caused by uneven road surfaces), the damping sheet can quickly respond and absorb this vibration energy, thereby reducing the vibration amplitude of the vehicle body's steel panels. By adjusting the proportions of each component and optimizing the preparation process, the damping sheet exhibits excellent damping performance under high-frequency excitation. This means that when the vehicle is traveling at high speed or encountering bumpy roads, the damping sheet can more effectively absorb and dissipate vibration energy, further reducing the vibration of the vehicle body's steel panels.

[0026] 4. This invention exhibits good heat resistance, cold resistance, and anti-aging properties. Butyl rubber material itself possesses excellent heat and cold resistance, maintaining stable performance under extreme temperature conditions and resisting deformation or aging. Simultaneously, an anti-aging agent is added to the formulation, further enhancing the heat resistance, cold resistance, and anti-aging properties of the damping sheet. These agents inhibit the oxidation and aging process of rubber materials under high or low temperature conditions, reducing performance limitations and extending the service life of the damping sheet.

[0027] 5. This invention reduces overall raw material costs by optimizing the raw material combination, using lower-cost raw material substitutes, and adjusting raw material ratios. The amount of raw materials used is controlled within a reasonable range, ensuring product performance while avoiding unnecessary waste. The optimized formula allows for smoother mixing and processing of raw materials, reducing losses and waste during production. Furthermore, the optimized formula undergoes rigorous quality control and stability testing, ensuring high product quality and long-term stability. This helps reduce rework and scrap rates due to quality issues, further lowering production costs.

[0028] 6. The formula of this invention contains less carbon black, which reduces the risk of environmental pollution. The increased barium sulfate content can improve radiation shielding performance, regulate the vulcanization characteristics of the material, thereby improving the physical and mechanical properties and heat resistance of rubber products; and barium sulfate can resist the erosion of environmental factors such as ultraviolet rays and ozone to a certain extent. Attached Figure Description

[0029] Figure 1 This is a peeling curve of the damping sheet sample in Example 1; Figure 2 This is a peeling curve of the damping sheet sample in Example 2; Figure 3 This is a peeling curve of the damping sheet sample in Example 3. Detailed Implementation

[0030] The present invention will now be described in further detail with reference to specific embodiments and accompanying drawings.

[0031] Example 1 This embodiment provides a high-performance automotive sound insulation and noise reduction damping sheet and its preparation method, comprising the following raw materials by weight: Butyl rubber: 15g; Barium sulfate: 125g; Polyisobutylene: 40g; Silicon dioxide: 10g; Carbon black: 0.5g; Anti-aging agent: 3g; Iron powder coated with iron(III) oxide: 175g.

[0032] The preparation method of the above-mentioned high-performance automotive sound insulation and noise reduction damping sheet is as follows: 1. Raw material preparation: Accurately weigh all raw materials according to the formula, and mix and homogenize them: use an internal mixer for colloid pretreatment, and then use a kneader to add and mix the various raw materials; 2. Mixing: Place the pretreated raw materials in an internal mixer and mix them at a temperature of 110℃ to ensure that the various components are evenly dispersed and blended. 3. Extrusion: The uniformly mixed material is evenly fed into the extruder and extruded into thin sheets through the die at 70°C; 4. Calendering: The extruded sheet material is fed into a three-roll calender for calendering to obtain the required thickness and flatness; 5. Cooling and curing: The calendered damping sheet is cooled (using natural cooling) to cure it and achieve the required physical properties.

[0033] The above-mentioned damping sheet and its preparation method have the following advantages: (1) The raw materials of the damping sheet include butyl rubber and barium sulfate. The high air tightness and water tightness of butyl rubber combined with the chemical stability of barium sulfate enable the product to maintain stable performance in harsh environments. Furthermore, the filling effect of barium sulfate can enhance the rigidity and wear resistance of the product.

[0034] (2) The raw materials of the damping sheet include polyisobutylene and anti-aging agent. The weather resistance, heat resistance and anti-aging properties of polyisobutylene can improve the environmental adaptability and overall durability of the product. The addition of anti-aging agent further extends the service life of the product and prevents performance degradation caused by aging.

[0035] (3) The raw materials of the damping sheet include silica, carbon black and butyl rubber. Silica and carbon black are used as reinforcing agents, which can significantly improve the tensile strength and hardness of butyl rubber. In addition, carbon black can also increase the conductivity and wear resistance of the product and improve the overall performance of the product.

[0036] (4) The raw material of the damping sheet includes iron powder. The addition of iron powder may affect the density, hardness or magnetism of the product. Furthermore, the interaction between iron powder and other components may produce some special properties, such as increasing the tear resistance or improving the wear resistance of the product.

[0037] (5) Equipment integration: The present invention uses advanced internal mixers, extruders and calenders to achieve equipment integration and automated control, reducing the number of equipment and manual operation.

[0038] (6) Process optimization: By optimizing the screw design (increasing the length-to-diameter ratio and double thread design), calender roll design (increasing the diameter and length of the roll and polishing or sandblasting the surface to improve its smoothness and wear resistance), and cooling parameters (mold temperature controller controlled at 50~80℃), the adaptability to different raw materials and formulas has been achieved, reducing the number of process adjustments and calibrations.

[0039] (7) Precise control: The use of precise metering systems (electronic loss-in-weight scales), temperature control systems (mold temperature controllers, mold coolers, chillers, etc.), pressure control systems, and size control systems (CCD monitoring, AOI judgment) has enabled precise control of raw material weighing, extrusion process, calendering process, and cooling process, thereby improving product quality and stability.

[0040] (8) Improve efficiency: By simplifying process steps and optimizing process parameters (extrusion temperature, mixing temperature, etc.), stable temperature and improved screw, the processing efficiency is improved, the production cost is reduced, and the quality and stability of the product are guaranteed.

[0041] Example 2 This embodiment provides a high-performance automotive sound insulation and noise reduction damping sheet and its preparation method, comprising the following raw materials by weight: Butyl rubber: 18g; Barium sulfate: 140g; Polyisobutylene: 35g; Silicon dioxide: 7g; Carbon black: 0.3g; Anti-aging agent: 4g; Iron powder coated with iron(III) oxide: 160g.

[0042] The specific preparation method is the same as in Example 1.

[0043] Example 3 This embodiment provides a high-performance automotive sound insulation and noise reduction damping sheet and its preparation method, comprising the following raw materials by weight: Butyl rubber: 12g; Barium sulfate: 130g; Polyisobutylene: 45g; Silicon dioxide: 12g; Carbon black: 0.8g; Anti-aging agent: 2g; Iron powder coated with iron oxide: 190g.

[0044] The specific preparation method is the same as in Example 1.

[0045] Example 4 This embodiment provides a high-performance automotive sound insulation and noise reduction damping sheet and its preparation method, comprising the following raw materials by weight: Butyl rubber: 10g; Barium sulfate: 100g; Polyisobutylene: 50g; Silicon dioxide: 20g; Carbon black: 1g; Anti-aging agent: 1g; Iron powder coated with iron(III) oxide: 200g.

[0046] The difference between the preparation method of the above-mentioned high-performance automotive sound insulation and noise reduction damping sheet and Example 1 is that: During mixing, the mixing temperature is 90℃; during extrusion, the extrusion temperature is 50℃. The rest is the same as in Example 1.

[0047] Comparative Example 1 This embodiment provides a damping sheet and its preparation method, comprising the following raw materials by weight: 25g of butyl rubber; 25g of polyisobutylene; 25g of paraffin oil; 0.4g of naphthenic oil; 290g of iron powder; 120g of barium sulfate; 10g of recycled rubber; Anti-aging agent 0.1g.

[0048] The preparation method of the above-mentioned anti-aging high-strength damping block is as follows: 1. Mixing: Place the weighed rubber raw materials (butyl rubber, polyisobutylene, reclaimed rubber) and (barium sulfate) into a high-speed mixer and premix them at about 70°C. Then, gradually add paraffin oil, naphthenic oil, iron powder, antioxidant, etc. after premixing. After mixing evenly, cool the material to room temperature to facilitate the subsequent extrusion process. 2. Extrusion: The cooled mixture is fed into a twin-screw extruder for extrusion at a temperature of 70°C, and extruded into thin sheets; 3. Forming: The extruded sheet is cooled by a cooling device and then shaped by a shaping device; the cooled and shaped sheet is cut into the required shape and size to ensure dimensional accuracy and surface flatness.

[0049] Comparative Example 2 This embodiment provides a damping sheet and its preparation method, comprising the following raw materials by weight: Butyl rubber: 15g; Barium sulfate: 125g; Polyisobutylene: 40g; Silicon dioxide: 10g; Carbon black: 0.5g; Anti-aging agent: 3g; Iron powder: 175g.

[0050] The specific preparation method is the same as in Example 1.

[0051] Application Example 1 Samples from Examples 1-4 and Comparative Examples 1-2 were taken and subjected to quality testing: 1. Damping Performance Testing: Damping coefficient testing measures the energy absorption and attenuation capacity of a material under vibration or impact conditions. A higher damping coefficient indicates better vibration reduction. Common testing methods include testing the dynamic modulus and loss factor using a dynamic mechanical analyzer (DMA). The relevant test parameters for Examples 1 to 5 are shown in Table 1, and the experimental results are shown in Table 2.

[0052] Table 1. Parameters related to damping performance testing 2. Environmental adaptability testing: This includes thermal aging testing, low-temperature brittleness testing, and damp heat aging testing. These tests evaluate the performance stability of the damping sheet under different temperature and humidity conditions, ensuring that it maintains good sound insulation and vibration reduction effects in actual use. Experimental data are shown in Table 2.

[0053] 3. Adhesion Test: A peel strength test was conducted (samples were attached to a steel plate, and the steel plate with the samples was placed in a fully automated intelligent temperature and humidity incubator at room temperature for 2 hours to test the 180° peel force). This evaluated the adhesion effect of the damping sheet to different materials, ensuring that the damping sheet will not detach or fail during long-term use. Experimental data are shown in Table 2.

[0054] Table 2 Damping sheet sample quality test data As shown in Table 2, the experimental data in the examples are all superior to those in the comparative examples. The damping sheet prepared by this invention has high peel strength and good adhesion; high damping performance and good vibration reduction effect; and it also has good resistance to thermal aging, high temperature, low temperature and damp heat aging.

[0055] The specific embodiments described herein are merely illustrative of the spirit of the invention. Those skilled in the art to which this invention pertains may make various modifications or additions to the described specific embodiments or use similar methods to substitute them, without departing from the spirit of the invention or exceeding the scope defined by the appended claims.

Claims

1. A high-performance automotive sound insulation and noise reduction damping sheet, characterized in that: It includes 10-20 parts by weight of butyl rubber, 100-150 parts of barium sulfate, 30-50 parts of polyisobutylene, 5-20 parts of silica, 0.1-1 parts of carbon black, 1-5 parts of antioxidant and 150-200 parts of iron powder. The iron powder is modified iron powder with a surface coated with a soft magnetic material; The soft magnetic material is iron(II,III) oxide, which is coated onto the surface of iron powder by liquid phase chemical deposition.

2. The high-performance automotive sound insulation and noise reduction damping sheet as described in claim 1, characterized in that: It includes 12-18 parts by weight of butyl rubber, 125-140 parts of barium sulfate, 35-45 parts of polyisobutylene, 7-12 parts of silica, 0.3-0.8 parts of carbon black, 2-4 parts of antioxidant and 160-190 parts of iron powder.

3. A method for preparing a high-performance automotive sound insulation and noise reduction damping sheet as described in any one of claims 1-2, characterized in that, Includes the following steps: Step 1: Raw material preparation. After accurately weighing each component raw material according to the proportion, pre-treatment is carried out. Step 2: Mixing. Place the pretreated raw materials in an internal mixer and mix them. Step 3: Extrusion. The uniformly mixed material is evenly fed into the extruder and extruded into thin sheets through the die. Step 4: Calendering. The extruded sheet material is fed into a three-roll calender for calendering to obtain the required thickness and flatness. Step 5: Cooling and curing. The calendered damping sheet is cooled to cure it and achieve the required physical properties.

4. The method for preparing a high-performance automotive sound insulation and noise reduction damping sheet as described in claim 3, characterized in that: The pretreatment in step one includes mixing and homogenizing the raw materials: using an internal mixer for colloid pretreatment, and then using a kneader to add the raw materials to the mixture.

5. The method for preparing a high-performance automotive sound insulation and noise reduction damping sheet as described in claim 3, characterized in that: The mixing temperature in step two is 90-150℃.

6. The method for preparing a high-performance automotive sound insulation and noise reduction damping sheet as described in claim 3, characterized in that: The extrusion temperature in step three is 50-90℃.

7. The method for preparing a high-performance automotive sound insulation and noise reduction damping sheet as described in claim 3, characterized in that: The rolling process in step four includes multiple rolling and finishing processes.

8. The method for preparing a high-performance automotive sound insulation and noise reduction damping sheet as described in claim 3, characterized in that: The cooling method in step five is either natural cooling or forced cooling.

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