A vibration-damping rubber material and a method for producing the same

Abstract

This invention provides a vibration-damping rubber material and its preparation method, comprising the following steps: starting an internal mixer, adding natural rubber, plasticizing, adding a softener and a composite foaming agent, and mixing; adding a filler, and continuing to mix after the torque stabilizes, discharging the rubber to obtain a first-stage compound; after resting for 12 hours, starting an open mill, feeding in the compound, and after it smoothly wraps around the rollers, adding a vulcanization accelerator and sulfur, cutting three times with left and right cutters, and sheeting to obtain a second-stage compound, which is then rested; and finally, vulcanizing and foaming the second-stage compound to obtain the final product. This invention utilizes a composite pore structure combined with modified glass flakes to achieve a synergistic vibration-damping effect. The composite pore structure combines nano-sized and micro-sized pores, prepared using ultrafine sodium bicarbonate particles and foaming agent H, respectively. The micro-pores and nano-pores are interspersed, making it difficult to form through-pores. Simultaneously, the external force can effectively diffuse from the micro-pores to the nano-pores for dissipation, thereby improving the vibration-damping effect.

Description

Technical Field

[0001] This invention relates to the field of functional rubber, specifically to a vibration-damping rubber material and its preparation method. Background Technology

[0002] Under dynamic conditions, any object with an imbalance will inevitably vibrate, and this vibration will inevitably produce noise. With the rapid development of modern industry, vibration and noise have become serious problems in various fields: they reduce operational precision and affect product quality; shorten product lifespan and cause high-precision instruments to malfunction; endanger safety and cause premature damage to equipment or structures; pollute the environment and affect human health; vibrations such as earthquakes can even cause significant damage to human life and property. Therefore, researching and mastering vibration control technology has become a major issue facing the industrial development of various countries. The most fundamental and best way to eliminate vibration and noise is to reduce or eliminate the vibration source. However, in reality, it is impossible to completely eliminate the vibration source. Therefore, other methods of vibration control must be adopted. The most widespread and effective method in practical applications is the use of various vibration damping products, especially rubber vibration damping products. These products can effectively isolate vibration from the excitation source and can also mitigate the vibration of the vibrating body. Therefore, they are widely used in the vibration isolation of power machinery such as aircraft, vehicles, and ships, as well as auxiliary equipment and instruments such as fans and pumps.

[0003] Rubber's combination of high elasticity and high viscosity makes it unparalleled in cushioning, vibration damping, and dynamic sealing. Rubber foam materials are conducive to impact deformation and have good vibration damping effects. However, the foaming process can easily lead to a decrease in its mechanical properties, thus limiting its applications. Therefore, how to improve the vibration damping performance of rubber materials without compromising their mechanical properties, or even improve them, is currently a key research area. Summary of the Invention

[0004] Technical problem to be solved: This invention addresses the current technical problem of poor vibration damping performance of rubber by employing a composite foam structure combined with modified glass flakes to achieve a combined vibration damping effect. The composite foam structure combines nano-sized and micro-sized foam structures, prepared using ultrafine sodium bicarbonate particles and foaming agent H, respectively. Simple micro-sized foam structures are prone to interconnection, forming through-holes, which prevent the transmission of external forces and result in poor vibration damping performance. It also affects mechanical properties. However, with the composite foam structure, micro-sized and nano-sized pores are interspersed, making it difficult for through-holes to form. At the same time, the external forces can be effectively diffused from the micro-sized pores to the nano-sized pores and dissipated, thereby improving the vibration damping effect.

[0005] Technical solution: A vibration damping rubber material, by weight, comprises the following components: 100 parts natural rubber, 8-10 parts filler, 5 parts softener, 3-7 parts composite foaming agent, 2 parts sulfur and 1 part vulcanization accelerator;

[0006] The filler is modified glass flakes.

[0007] Furthermore, the method for preparing the modified glass flakes is as follows:

[0008] Step 1: Take ethyl acrylate and vinyl acetate, mix them thoroughly to obtain mixed monomers;

[0009] Step 2: Add ammonium persulfate solution and stir for 5 minutes;

[0010] Step 3: Add glass flakes, sonicate for 5-10 minutes, place in a sealed container, and heat to 65-75℃ for 3 hours;

[0011] Step 4: After the reaction is complete, centrifuge and dry in a vacuum drying oven until constant weight to obtain modified glass flakes.

[0012] Furthermore, the mass ratio of ethyl acrylate to vinyl acetate is 4:5.

[0013] Furthermore, the concentration of the ammonium persulfate solution is 9.0 × 10⁻⁶. -3 mol / L.

[0014] Furthermore, the glass flakes are 5-50 μm in size and <400 nm in thickness.

[0015] Furthermore, the mass ratio of the mixed monomer to the glass flakes is (1-4):50.

[0016] Furthermore, the composite foaming agent is composed of ultrafine sodium bicarbonate particles and foaming agent H in a mass ratio of (1-2):1.

[0017] Furthermore, the ultrafine sodium bicarbonate particles have a particle size of 110-150 nm.

[0018] Furthermore, the preparation method of the ultrafine sodium bicarbonate particles is as follows, by weight:

[0019] Step 1: Take 10 parts sodium bicarbonate and 90 parts water, stir to dissolve, add 0.5 parts sodium dodecyl sulfate, stir, and obtain sodium bicarbonate solution;

[0020] Step 2: Place 1000 parts of anhydrous ethanol in a stirrer, and add sodium bicarbonate solution to the anhydrous ethanol at a stirring speed of 1100-1200 rpm and a temperature of -5℃ at a stirring speed of 1mL / min.

[0021] Step 3: Vacuum filtration to separate the precipitate from the liquid, and wash with anhydrous ethanol 2-3 times;

[0022] Step 4: Place the precipitate under vacuum at 40°C, remove and grind to obtain ultrafine sodium bicarbonate particles.

[0023] The preparation method of the above-mentioned vibration-damping rubber material includes the following steps:

[0024] (1) Start the internal mixer, add natural rubber, plasticize for 1 min, add softener and composite foaming agent, and mix for 1 min;

[0025] (2) Add filler, and continue mixing for 5 minutes after the torque stabilizes. Then discharge the rubber to obtain a first-stage compound.

[0026] (3) After standing for 12 hours, start the open mill, add the mixed rubber, and after it is smoothed around the rollers, add vulcanization accelerator and sulfur, cut the left and right blades 3 times, and cut the sheet to obtain the two-stage mixed rubber. Let it stand for 2 hours.

[0027] (4) The two-stage compound is vulcanized and foamed at 150°C for 10-15 minutes using a flat vulcanizing machine. Beneficial effects

[0028] This invention uses composite foam combined with modified glass flakes to achieve a synergistic vibration reduction effect.

[0029] In this invention, the composite foam combines nano-sized and micro-sized foams, prepared using ultrafine sodium bicarbonate particles and foaming agent H, respectively. Simple micro-sized foams are prone to interconnection, forming through-holes, which prevents the transmission of external forces, resulting in poor vibration damping and affecting mechanical properties. However, with the composite foam, micro-sized and nano-sized pores are interspersed, making it less likely for through-holes to form. At the same time, the external forces can be effectively diffused from the micro-sized pores to the nano-sized pores and dissipated, thus improving the vibration damping effect.

[0030] This invention utilizes modified glass flakes, which are layered and their surface can physically and chemically adsorb onto natural rubber. When subjected to external impact, the modified glass flakes can restrict the movement of natural rubber chain segments, altering the conformation and orientation of nearby molecular chains and broadening the conformational distribution, thereby achieving a vibration damping effect. Where the adsorption between natural rubber and the modified glass flake surface is weak, relative slippage occurs between the polymer chains and the modified glass flakes, increasing the damping performance of the system.

[0031] This invention modifies glass flakes by grafting polymers to make their surface properties compatible with natural rubber, improving their dispersibility in natural rubber and further reducing the impact of direct addition on the mechanical properties of natural rubber. At the same time, by modifying the glass flakes, a "whole network effect" can be formed in the natural rubber, resulting in better mechanical properties for the vibration damping rubber.

[0032] The dynamic-to-static stiffness ratio of the vibration-damping rubber roller material of this invention can be as low as 1.04, resulting in good vibration damping effect and excellent mechanical properties. Detailed Implementation Example 1

[0033] The preparation method of modified glass flakes is as follows:

[0034] Step 1: Take 4g of ethyl acrylate and 5g of vinyl acetate, mix them thoroughly to obtain a mixed monomer;

[0035] Step 2: Add an excess concentration of 9.0 × 10 -3 A mol / L ammonium persulfate solution was stirred for 5 minutes.

[0036] Step 3: Add 450g of glass flakes, sonicate for 5-10 minutes, place in a sealed container, and heat to 65-75℃ for 3 hours; the glass flakes should be 5-50μm in size and <400nm thick.

[0037] Step 4: After the reaction is complete, centrifuge and dry in a vacuum drying oven until constant weight to obtain modified glass flakes. Example 2

[0038] Step 1: Take 4g of ethyl acrylate and 5g of vinyl acetate, mix them thoroughly to obtain a mixed monomer;

[0039] Step 2: Add an excess concentration of 9.0 × 10 -3 A mol / L ammonium persulfate solution was stirred for 5 minutes.

[0040] Step 3: Add 225g of glass flakes, sonicate for 5-10 minutes, place in a sealed container, and heat to 65-75℃ for 3 hours; the glass flakes should be 5-50μm in size and <400nm thick.

[0041] Step 4: After the reaction is complete, centrifuge and dry in a vacuum drying oven until constant weight to obtain modified glass flakes. Example 3

[0042] Step 1: Take 4g of ethyl acrylate and 5g of vinyl acetate, mix them thoroughly to obtain a mixed monomer;

[0043] Step 2: Add an excess concentration of 9.0 × 10 -3 A mol / L ammonium persulfate solution was stirred for 5 minutes.

[0044] Step 3: Add 115g of glass flakes, sonicate for 5-10 minutes, place in a sealed container, and heat to 65-75℃ for 3 hours; the glass flakes should be 5-50μm in size and <400nm thick.

[0045] Step 4: After the reaction is complete, centrifuge and dry in a vacuum drying oven until constant weight to obtain modified glass flakes.

[0046] The grafting rate is determined using the following formula:

[0047]

[0048] Grafting rate (%) Example 1 80.4 Example 2 85.7 Example 3 86.3

[0049] Considering both the grafting rate and the avoidance of resource waste, the modified glass flakes prepared in Example 2 were selected. Example 4

[0050] The preparation method of ultrafine sodium bicarbonate particles is as follows, by weight:

[0051] Step 1: Take 10g of sodium bicarbonate and 90g of water, stir to dissolve, add 0.5g of sodium dodecyl sulfate, stir, and obtain sodium bicarbonate solution;

[0052] Step 2: Place 1000g of anhydrous ethanol in a stirrer, and add sodium bicarbonate solution to the anhydrous ethanol at a stirring speed of 1100-1200 rpm and a temperature of -5℃ at a stirring speed of 1mL / min.

[0053] Step 3: Vacuum filtration to separate the precipitate from the liquid, and wash three times with anhydrous ethanol;

[0054] Step 4: Place the precipitate under vacuum drying at 40℃, take it out, grind it, and screen it to obtain ultrafine sodium bicarbonate particles with a particle size of 110-150nm. Example 5

[0055] A method for preparing a vibration-damping rubber material includes the following steps:

[0056] (1) Start the internal mixer, add 100 parts of natural rubber, plasticize for 1 min, add 5 parts of softener and 3 parts of composite foaming agent. The composite foaming agent is ultrafine sodium bicarbonate particles and foaming agent H with a mass ratio of 1.5:1, and mix for 1 min.

[0057] (2) Add 9 parts of the modified glass flakes prepared in Example 2, and continue mixing for 5 minutes after the torque stabilizes. Then, remove the glue to obtain a first-stage compound.

[0058] (3) After standing for 12 hours, start the open mill, add the mixed rubber, and after it is smoothed around the rollers, add 1 part of vulcanization accelerator M and 2 parts of sulfur. Cut the left and right blades 3 times, and cut the sheet to obtain the two-stage mixed rubber. Let it stand for 2 hours.

[0059] (4) The two-stage compound is vulcanized and foamed at 150°C for 13 minutes using a flat vulcanizing machine. Example 6

[0060] A method for preparing a vibration-damping rubber material includes the following steps:

[0061] (1) Start the internal mixer, add 100 parts of natural rubber, plasticize for 1 min, add 5 parts of softener and 5 parts of composite foaming agent. The composite foaming agent is ultrafine sodium bicarbonate particles with a mass ratio of 1.5:1 and foaming agent H, mix for 1 min.

[0062] (2) Add 9 parts of the modified glass flakes prepared in Example 2, and continue mixing for 5 minutes after the torque stabilizes. Then, remove the glue to obtain a first-stage compound.

[0063] (3) After standing for 12 hours, start the open mill, add the mixed rubber, and after it is smoothed around the rollers, add 1 part of vulcanization accelerator M and 2 parts of sulfur. Cut the left and right blades 3 times, and cut the sheet to obtain the two-stage mixed rubber. Let it stand for 2 hours.

[0064] (4) The two-stage compound is vulcanized and foamed at 150°C for 13 minutes using a flat vulcanizing machine. Example 7

[0065] A method for preparing a vibration-damping rubber material includes the following steps:

[0066] (1) Start the internal mixer, add 100 parts of natural rubber, plasticize for 1 min, add 5 parts of softener and 7 parts of composite foaming agent. The composite foaming agent is ultrafine sodium bicarbonate particles with a mass ratio of 1.5:1 and foaming agent H, mix for 1 min.

[0067] (2) Add 9 parts of the modified glass flakes prepared in Example 2, and continue mixing for 5 minutes after the torque stabilizes. Then, remove the glue to obtain a first-stage compound.

[0068] (3) After standing for 12 hours, start the open mill, add the mixed rubber, and after it is smoothed around the rollers, add 1 part of vulcanization accelerator M and 2 parts of sulfur. Cut the left and right blades 3 times, and cut the sheet to obtain the two-stage mixed rubber. Let it stand for 2 hours.

[0069] (4) The two-stage compound is vulcanized and foamed at 150°C for 13 minutes using a flat vulcanizing machine. Example 8

[0070] A method for preparing a vibration-damping rubber material includes the following steps:

[0071] (1) Start the internal mixer, add 100 parts of natural rubber, plasticize for 1 min, add 5 parts of softener and 5 parts of composite foaming agent. The composite foaming agent is ultrafine sodium bicarbonate particles and foaming agent H with a mass ratio of 1:1, and mix for 1 min.

[0072] (2) Add 9 parts of the modified glass flakes prepared in Example 2, and continue mixing for 5 minutes after the torque stabilizes. Then, remove the glue to obtain a first-stage compound.

[0073] (3) After standing for 12 hours, start the open mill, add the mixed rubber, and after it is smoothed around the rollers, add 1 part of vulcanization accelerator M and 2 parts of sulfur. Cut the left and right blades 3 times, and cut the sheet to obtain the two-stage mixed rubber. Let it stand for 2 hours.

[0074] (4) The two-stage compound is vulcanized and foamed at 150°C for 13 minutes using a flat vulcanizing machine. Example 9

[0075] A method for preparing a vibration-damping rubber material includes the following steps:

[0076] (1) Start the internal mixer, add 100 parts of natural rubber, plasticize for 1 min, add 5 parts of softener and 5 parts of composite foaming agent. The composite foaming agent is ultrafine sodium bicarbonate particles and foaming agent H with a mass ratio of 2:1, and mix for 1 min.

[0077] (2) Add 9 parts of the modified glass flakes prepared in Example 2, and continue mixing for 5 minutes after the torque stabilizes. Then, remove the glue to obtain a first-stage compound.

[0078] (3) After standing for 12 hours, start the open mill, add the mixed rubber, and after it is smoothed around the rollers, add 1 part of vulcanization accelerator M and 2 parts of sulfur. Cut the left and right blades 3 times, and cut the sheet to obtain the two-stage mixed rubber. Let it stand for 2 hours.

[0079] (4) The two-stage compound is vulcanized and foamed at 150°C for 13 minutes using a flat vulcanizing machine. Example 10

[0080] A method for preparing a vibration-damping rubber material includes the following steps:

[0081] (1) Start the internal mixer, add 100 parts of natural rubber, plasticize for 1 min, add 5 parts of softener and 5 parts of composite foaming agent. The composite foaming agent is ultrafine sodium bicarbonate particles with a mass ratio of 1.5:1 and foaming agent H, mix for 1 min.

[0082] (2) Add 8 parts of the modified glass flakes prepared in Example 2, and continue mixing for 5 minutes after the torque stabilizes. Then, remove the glue to obtain a first-stage compound.

[0083] (3) After standing for 12 hours, start the open mill, add the mixed rubber, and after it is smoothed around the rollers, add 1 part of vulcanization accelerator M and 2 parts of sulfur. Cut the left and right blades 3 times, and cut the sheet to obtain the two-stage mixed rubber. Let it stand for 2 hours.

[0084] (4) The two-stage compound is vulcanized and foamed at 150°C for 13 minutes using a flat vulcanizing machine. Example 11

[0085] A method for preparing a vibration-damping rubber material includes the following steps:

[0086] (1) Start the internal mixer, add 100 parts of natural rubber, plasticize for 1 min, add 5 parts of softener and 5 parts of composite foaming agent. The composite foaming agent is ultrafine sodium bicarbonate particles with a mass ratio of 1.5:1 and foaming agent H, mix for 1 min.

[0087] (2) Add 10 parts of the modified glass flakes prepared in Example 2, and continue mixing for 5 minutes after the torque stabilizes. Then, remove the glue to obtain a first-stage compound.

[0088] (3) After standing for 12 hours, start the open mill, add the mixed rubber, and after it is smoothed around the rollers, add 1 part of vulcanization accelerator M and 2 parts of sulfur. Cut the left and right blades 3 times, and cut the sheet to obtain the two-stage mixed rubber. Let it stand for 2 hours.

[0089] (4) The two-stage compound is vulcanized and foamed at 150°C for 13 minutes using a flat vulcanizing machine. Example 12

[0090] A method for preparing a vibration-damping rubber material includes the following steps:

[0091] (1) Start the internal mixer, add 100 parts of natural rubber, plasticize for 1 min, add 5 parts of softener and 5 parts of composite foaming agent. The composite foaming agent is ultrafine sodium bicarbonate particles with a mass ratio of 1.5:1 and foaming agent H, mix for 1 min.

[0092] (2) Add 9 parts of the modified glass flakes prepared in Example 2, and continue mixing for 5 minutes after the torque stabilizes. Then, remove the glue to obtain a first-stage compound.

[0093] (3) After standing for 12 hours, start the open mill, add the mixed rubber, and after it is smoothed around the rollers, add 1 part of vulcanization accelerator M and 2 parts of sulfur. Cut the left and right blades 3 times, and cut the sheet to obtain the two-stage mixed rubber. Let it stand for 2 hours.

[0094] (4) The two-stage compound is vulcanized and foamed at 150°C for 10 minutes using a flat vulcanizing machine. Example 13

[0095] A method for preparing a vibration-damping rubber material includes the following steps:

[0096] (1) Start the internal mixer, add 100 parts of natural rubber, plasticize for 1 min, add 5 parts of softener and 5 parts of composite foaming agent. The composite foaming agent is ultrafine sodium bicarbonate particles with a mass ratio of 1.5:1 and foaming agent H, mix for 1 min.

[0097] (2) Add 9 parts of the modified glass flakes prepared in Example 2, and continue mixing for 5 minutes after the torque stabilizes. Then, remove the glue to obtain a first-stage compound.

[0098] (3) After standing for 12 hours, start the open mill, add the mixed rubber, and after it is smoothed around the rollers, add 1 part of vulcanization accelerator M and 2 parts of sulfur. Cut the left and right blades 3 times, and cut the sheet to obtain the two-stage mixed rubber. Let it stand for 2 hours.

[0099] (4) The two-stage compound is vulcanized and foamed at 150°C for 15 minutes using a flat vulcanizing machine.

[0100] The cell size of the above embodiments was measured, and the results showed that they were all composite cells of nano-sized and micro-sized cells, with nano-sized cells ranging from 100 to 500 nm and micro-sized cells ranging from 30 to 300 μm. Comparative Example 1

[0101] The difference between this embodiment and Embodiment 6 is that a composite foaming agent is not used; instead, ultrafine sodium bicarbonate particles are used entirely. Specifically:

[0102] A method for preparing a vibration-damping rubber material includes the following steps:

[0103] (1) Start the internal mixer, add 100 parts of natural rubber, plasticize for 1 min, add 5 parts of softener and 5 parts of ultrafine sodium bicarbonate granules, and mix for 1 min;

[0104] (2) Add 9 parts of the modified glass flakes prepared in Example 2, and continue mixing for 5 minutes after the torque stabilizes. Then, remove the glue to obtain a first-stage compound.

[0105] (3) After standing for 12 hours, start the open mill, add the mixed rubber, and after it is smoothed around the rollers, add 1 part of vulcanization accelerator M and 2 parts of sulfur. Cut the left and right blades 3 times, and cut the sheet to obtain the two-stage mixed rubber. Let it stand for 2 hours.

[0106] (4) The two-stage compound is vulcanized and foamed at 150°C for 13 minutes using a flat vulcanizing machine. Comparative Example 2

[0107] The difference between this embodiment and Embodiment 6 is that a composite foaming agent is not used; instead, foaming agent H is used exclusively. Specifically:

[0108] A method for preparing a vibration-damping rubber material includes the following steps:

[0109] (1) Start the internal mixer, add 100 parts of natural rubber, plasticize for 1 min, add 5 parts of softener and 5 parts of foaming agent H, and mix for 1 min;

[0110] (2) Add 9 parts of the modified glass flakes prepared in Example 2, and continue mixing for 5 minutes after the torque stabilizes. Then, remove the glue to obtain a first-stage compound.

[0111] (3) After standing for 12 hours, start the open mill, add the mixed rubber, and after it is smoothed around the rollers, add 1 part of vulcanization accelerator M and 2 parts of sulfur. Cut the left and right blades 3 times, and cut the sheet to obtain the two-stage mixed rubber. Let it stand for 2 hours.

[0112] (4) The two-stage compound is vulcanized and foamed at 150°C for 13 minutes using a flat vulcanizing machine. Comparative Example 3

[0113] The difference between this embodiment and Embodiment 6 is that modified glass flakes are not added. Specifically:

[0114] A method for preparing a vibration-damping rubber material includes the following steps:

[0115] (1) Start the internal mixer, add 100 parts of natural rubber, plasticize for 1 min, add 5 parts of softener and 5 parts of composite foaming agent. The composite foaming agent is ultrafine sodium bicarbonate particles and foaming agent H with a mass ratio of 1.5:1. Mix for 6 min, discharge the rubber, and obtain a first-stage compound rubber.

[0116] (2) After standing for 12 hours, start the open mill, add the compound rubber, and after it is smoothed around the rollers, add 1 part of vulcanization accelerator M and 2 parts of sulfur. Cut the left and right blades 3 times, and cut the sheet to obtain the second-stage compound rubber. Let it stand for 2 hours.

[0117] (3) The two-stage compound is vulcanized and foamed at 150°C for 13 minutes using a flat vulcanizing machine. Comparative Example 4

[0118] The difference between this embodiment and Embodiment 6 is the addition of unmodified glass flakes, specifically:

[0119] A method for preparing a vibration-damping rubber material includes the following steps:

[0120] (1) Start the internal mixer, add 100 parts of natural rubber, plasticize for 1 min, add 5 parts of softener and 5 parts of composite foaming agent. The composite foaming agent is ultrafine sodium bicarbonate particles with a mass ratio of 1.5:1 and foaming agent H, mix for 1 min.

[0121] (2) Add 9 parts of glass flakes, and continue mixing for 5 minutes after the torque stabilizes. Then drain the glue to obtain a first-stage compound.

[0122] (3) After standing for 12 hours, start the open mill, add the mixed rubber, and after it is smoothed around the rollers, add 1 part of vulcanization accelerator M and 2 parts of sulfur. Cut the left and right blades 3 times, and cut the sheet to obtain the two-stage mixed rubber. Let it stand for 2 hours.

[0123] (4) The two-stage compound is vulcanized and foamed at 150°C for 13 minutes using a flat vulcanizing machine. Comparative Example 5

[0124] The difference between this embodiment and Embodiment 6 is that the vulcanization foaming time is 5 minutes. Specifically:

[0125] A method for preparing a vibration-damping rubber material includes the following steps:

[0126] (1) Start the internal mixer, add 100 parts of natural rubber, plasticize for 1 min, add 5 parts of softener and 5 parts of composite foaming agent. The composite foaming agent is ultrafine sodium bicarbonate particles with a mass ratio of 1.5:1 and foaming agent H, mix for 1 min.

[0127] (2) Add 9 parts of the modified glass flakes prepared in Example 2, and continue mixing for 5 minutes after the torque stabilizes. Then, remove the glue to obtain a first-stage compound.

[0128] (3) After standing for 12 hours, start the open mill, add the mixed rubber, and after it is smoothed around the rollers, add 1 part of vulcanization accelerator M and 2 parts of sulfur. Cut the left and right blades 3 times, and cut the sheet to obtain the two-stage mixed rubber. Let it stand for 2 hours.

[0129] (4) The two-stage compound is vulcanized and foamed at 150°C for 5 minutes using a flat vulcanizing machine. Comparative Example 6

[0130] The difference between this embodiment and Embodiment 6 is that the vulcanization foaming time is 20 minutes. Specifically:

[0131] A method for preparing a vibration-damping rubber material includes the following steps:

[0132] (1) Start the internal mixer, add 100 parts of natural rubber, plasticize for 1 min, add 5 parts of softener and 5 parts of composite foaming agent. The composite foaming agent is ultrafine sodium bicarbonate particles with a mass ratio of 1.5:1 and foaming agent H, mix for 1 min.

[0133] (2) Add 9 parts of the modified glass flakes prepared in Example 2, and continue mixing for 5 minutes after the torque stabilizes. Then, remove the glue to obtain a first-stage compound.

[0134] (3) After standing for 12 hours, start the open mill, add the mixed rubber, and after it is smoothed around the rollers, add 1 part of vulcanization accelerator M and 2 parts of sulfur. Cut the left and right blades 3 times, and cut the sheet to obtain the two-stage mixed rubber. Let it stand for 2 hours.

[0135] (4) The two-stage compound is vulcanized and foamed at 150°C for 20 minutes using a flat vulcanizing machine.

[0136] The materials of each embodiment were prepared into 50mm×50mm×40mm samples. Their static properties were tested on a mechanical property testing machine using the national standard method. Then, vibration tests were conducted to obtain the frequency response function. The dynamic stiffness and static stiffness of the materials were tested, and their dynamic-to-static stiffness ratio was calculated.

[0137] Table 1. Dynamic and static stiffness ratios of different embodiments

[0138] Dynamic stiffness ratio Example 5 1.11 Example 6 1.04 Example 7 1.06 Example 8 1.06 Example 9 1.07 Example 10 1.10 Example 11 1.08 Example 12 1.16 Example 13 1.06 Comparative Example 1 1.27 Comparative Example 2 1.20 Comparative Example 3 1.37 Comparative Example 4 1.15 Comparative Example 5 1.53 Comparative Example 6 1.11

[0139] The dynamic-to-static stiffness ratio is closely related to vibration transmission and vibration reduction effect. The smaller the dynamic-to-static stiffness ratio, the better the resilience and the better the vibration transmission effect. The closer the value is to 1, the better the vibration transmission effect and the better the vibration reduction performance.

[0140] Tensile strength and elongation at break were tested using a German electronic tensile testing machine according to the national standard GB / T528-2009, with a tensile rate of 500 mm / min.

[0141] Compression set was tested according to the national standard GB / T7759.1-2015. The test conditions were (70±1)℃, 24h, and the compression rate was 25%.

[0142] Table 2 Mechanical properties of different embodiments

[0143] Tensile strength (MPa) Elongation at break (%) Compression set (%) Example 5 21.42 530 17.9 Example 6 20.17 549 18.8 Example 7 18.49 525 18.5 Example 8 19.88 541 18.5 Example 9 20.03 536 18.9 Example 10 19.83 524 18.4 Example 11 20.36 528 18.7 Example 12 20.56 537 17.3 Example 13 19.51 529 18.6 Comparative Example 1 20.39 552 18.3 Comparative Example 2 15.19 463 12.8 Comparative Example 3 17.96 501 17.9 Comparative Example 4 19.22 518 18.5 Comparative Example 5 20.56 530 17.0 Comparative Example 6 15.22 419 11.9

Claims

1. A vibration-damping rubber material, characterized in that, By weight, it includes the following components: 100 parts natural rubber, 8-10 parts filler, 5 parts softener, 3-7 parts compound foaming agent, 2 parts sulfur and 1 part vulcanization accelerator; The filler is modified glass flakes; The method for preparing the modified glass flakes is as follows: Step 1: Take ethyl acrylate and vinyl acetate, mix them thoroughly to obtain mixed monomers; Step 2: Add ammonium persulfate solution and stir for 5 minutes; Step 3: Add glass flakes, sonicate for 5-10 minutes, place in a sealed container, and heat to 65-75℃ for 3 hours; Step 4: After the reaction is complete, centrifuge and dry in a vacuum drying oven until constant weight to obtain modified glass flakes; The glass flakes are 5-50 μm in size and <400 nm in thickness; The composite foaming agent is composed of ultrafine sodium bicarbonate particles and foaming agent H in a mass ratio of (1-2):

1.

2. The vibration-damping rubber material according to claim 1, characterized in that, The mass ratio of ethyl acrylate to vinyl acetate is 4:

5.

3. The vibration-damping rubber material according to claim 1, characterized in that, The concentration of the ammonium persulfate solution is 9.0 × 10⁻⁶. -3 mol / L.

4. The vibration-damping rubber material according to claim 1, characterized in that, The mass ratio of the mixed monomer to the glass flakes is (1-4):

50.

5. The vibration-damping rubber material according to claim 1, characterized in that, The ultrafine sodium bicarbonate particles have a particle size of 110-150 nm.

6. The vibration-damping rubber material according to claim 1, characterized in that, The preparation method of the ultrafine sodium bicarbonate particles is as follows, by weight: Step 1: Take 10 parts sodium bicarbonate and 90 parts water, stir to dissolve, add 0.5 parts sodium dodecyl sulfate, stir, and obtain sodium bicarbonate solution; Step 2: Place 1000 parts of anhydrous ethanol in a stirrer, and add sodium bicarbonate solution to the anhydrous ethanol at a stirring speed of 1100-1200 rpm and a temperature of -5℃ at a stirring speed of 1mL / min. Step 3: Vacuum filtration to separate the precipitate from the liquid, and wash with anhydrous ethanol 2-3 times; Step 4: Place the precipitate under vacuum at 40°C, remove and grind to obtain ultrafine sodium bicarbonate particles.

7. A method for preparing a vibration-damping rubber material according to any one of claims 1-6, characterized in that, Includes the following steps: (1) Start the internal mixer, add natural rubber, plasticize for 1 min, add softener and composite foaming agent, and mix for 1 min; (2) Add filler, and continue mixing for 5 minutes after the torque stabilizes. Then discharge the rubber to obtain a first-stage compound. (3) After standing for 12 hours, start the open mill, add the mixed rubber, and after it is smoothed around the rollers, add vulcanization accelerator and sulfur, cut the left and right blades 3 times, and cut the sheet to obtain the two-stage mixed rubber. Let it stand for 2 hours. (4) The two-stage compound is vulcanized and foamed at 150°C for 10-15 minutes using a flat vulcanizing machine.