Preparation method of wear-resistant damping rubber

Abstract

The invention relates to a preparation method of wear-resistant damping rubber, and belongs to the technical field of composite materials. According to the invention, self-made modified nano silicon dioxide, butadiene styrene rubber, a peptizer, zinc oxide, stearic acid, an anti-aging agent, coumarone indene resin, sulfur and an accelerant are used as raw materials to prepare the wear-resistant damping rubber. Zinc oxide, stearic acid, an anti-aging agent and coumarone resin are added into an internal mixer for mixing, silicone rubber and modified nano silicon dioxide are added into the internal mixer for mixing and mixing, finally, the mixed rubber is discharged into open mixing equipment for open mixing and then vulcanized, and the wear-resistant damping rubber is obtained. The silicone rubber and the modified nano silicon dioxide are compounded to modify the styrene-butadiene rubber, so that the processability of the styrene-butadiene rubber can be improved, the mixing efficiency can be improved, and the overall damping effect and wear resistance of the compounded rubber can be effectively improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of composite materials, and specifically, relates to a preparation method of wear-resistant and shock-absorbing rubber. Background Art

[0002] With the rapid development of automotive industry technology, automobile manufacturing is continuously improving comfort, safety and driving experience. This trend places higher requirements on rubber shock-absorbing components. Shock-absorbing rubber is widely used in key parts such as automobile frames, strut devices, suspension bushings, aligning bearing brackets, bump stoppers and torsional vibration dampers, thus significantly improving the safety performance and driving comfort of automobiles.

[0003] By adding fillers to enhance the interaction between rubber molecules, thereby increasing internal friction and improving the energy dissipation ability, the shock-absorbing performance of rubber can be effectively improved. Nano-silica can improve the strength, wear resistance and tear resistance of rubber, and extend the service life of shock-absorbing components. It is an excellent rubber filler. However, there are a large number of strongly polar silanol groups on the surface of nano-silica. Therefore, nano-silica is prone to agglomeration itself, and has poor dispersibility and compatibility in non-polar rubber matrices. Poor dispersibility may lead to local stress concentration, affecting the shock-absorbing performance of rubber, and poor compatibility may lead to the destruction of the cross-linked structure inside the rubber, resulting in the overflow of rubber additives. Based on this, the present invention provides a preparation method of wear-resistant and shock-absorbing rubber. Summary of the Invention

[0004] The purpose of the present invention is to provide a preparation method of wear-resistant and shock-absorbing rubber to solve the problems mentioned in the above background art.

[0005] The purpose of the present invention can be achieved by the following technical solutions:

[0006] A preparation method of wear-resistant and shock-absorbing rubber includes the following steps:

[0007] First step: After drying nano-silica overnight in an oven at 100 °C, add it to a three-necked flask filled with anhydrous toluene, install a condenser and a thermometer, start magnetic stirring, and then add γ-glycidoxypropyltrimethoxysilane to the three-necked flask, and react at a temperature of 80-90 °C for 6 h. After the reaction is completed, filter out the solid, wash the obtained solid with anhydrous ethanol and dry it to obtain silane coupling agent-modified nano-silica;

[0008] Step 2: Mix the silane coupling agent modified nano-silica, N-tert-butyl-2-benzothiazole sulfenamide, and anhydrous toluene in a three-necked flask. Install a condenser and a thermometer, turn on the magnetic stirrer, and introduce nitrogen into the three-necked flask to exhaust the air in the flask. Then, react at a temperature of 90 - 100 °C for 4 h. After the reaction, filter out the solid, wash the obtained solid with anhydrous ethanol, and dry it to obtain the modified nano-silica;

[0009] Step 3: Add styrene-butadiene rubber and plasticizer into a kneader. The kneading temperature is 60 - 70 °C. Stir for 3 - 5 min, mix well, and then let it stand for 24 h for standby;

[0010] Step 4: Add zinc oxide, stearic acid, antioxidant, and coumarone resin into the kneader. The kneading temperature is 60 - 70 °C. Stir for 2 - 4 min, mix well, and then plastify for 1 min. Then, add silicone rubber and modified nano-silica into the kneader. During this process, continuously raise the temperature and stir for 6 - 8 min to mix;

[0011] Step 5: Raise the kneading temperature to 130 - 140 °C, then discharge the rubber to an open mill. After the open milling is completed, cool it to room temperature and let it stand for 24 h. Then, add the cooled and standing kneaded rubber, sulfur, and accelerator into the kneader, raise the temperature to 70 - 80 °C, and stir for 8 - 10 min to mix. After the mixing is completed, discharge the rubber to the open mill. After the open milling is completed, a wear-resistant and shock-absorbing rubber is obtained.

[0012] Further, the plasticizer is plasticizer SJ-103.

[0013] Further, the antioxidant is antioxidant RD (TMQ).

[0014] Further, the accelerator is tetrabenzylthiuram disulfide.

[0015] Further, the specification of the nano-silica is 10 - 40 nm.

[0016] Further, the dosage ratio of the nano-silica, anhydrous toluene, and γ-glycidoxypropyltrimethoxysilane used in the first step is 5 g : 150 - 200 mL : 2 - 3 g.

[0017] Further, the dosage ratio of the N-tert-butyl-2-benzothiazole sulfenamide and anhydrous toluene used in the second step is 2 - 2.8 g : 150 - 200 mL.

[0018] Further, the stirring speed of the kneader is 30 - 40 rpm.

[0019] Further, the pressure of the pressing hammer of the kneader is 0.6 - 0.8 MPa.

[0020] Further, by mass parts, the mass parts of each raw material used in the third, fourth, and fifth steps are as follows: styrene-butadiene rubber 100 parts, plasticizer 0.5 - 1.5 parts, zinc oxide 4.5 - 6.5 parts, stearic acid 3 - 5 parts, antioxidant 0.3 - 0.5 parts, coumarone resin 2 - 3 parts, silicone rubber 25 - 35 parts, modified nano-silica 30 - 40 parts, sulfur 1.8 - 2.6 parts, accelerator 0.4 - 0.6 parts.

[0021] Advantages of the present invention:

[0022] 1) The present invention selects silane coupling agent kh-560 γ-glycidoxypropyltrimethoxysilane to modify nano-silica. The siloxane bonds on the surface of γ-glycidoxypropyltrimethoxysilane react with the hydroxyl groups on the surface of nano-silica and graft onto the surface of nano-silica to obtain silane coupling agent-modified nano-silica with epoxy groups. Then, by using the addition reaction of epoxy groups and amino groups, accelerator N-tert-butyl-2-benzothiazolesulfenamide is grafted onto the surface of nano-silica to obtain a kind of modified nano-silica. The surface of the nano-silica in the present invention is grafted with hydrophobic organic groups, reducing the number of polar hydroxyl groups, improving the defect of easy agglomeration of nano-silica itself, and enhancing the dispersibility of nano-silica in the rubber matrix. In addition, the surface of the modified nano-silica is grafted with accelerator N-tert-butyl-2-benzothiazolesulfenamide, which can directly participate in the vulcanization of rubber chains without destroying the cross-linking structure inside the rubber. After vulcanization, a cross-linked rubber chain polymer layer is coated on the surface of the modified nano-silica, strengthening the interfacial interaction between the modified nano-silica and the inside of the rubber.

[0023] 2) The present invention uses self-made modified nano-silica, styrene-butadiene rubber, plasticizer, zinc oxide, stearic acid, antioxidant, coumarone resin, sulfur, and accelerator as raw materials to prepare a wear-resistant and shock-absorbing rubber. The preparation method of the present invention first mixes and kneads styrene-butadiene rubber and plasticizer, then adds zinc oxide, stearic acid, antioxidant, and coumarone resin into the kneader for mixing and kneading, then adds silicone rubber and modified nano-silica into the kneader for mixing and kneading, and finally discharges the kneaded rubber to an open mill for open milling and vulcanization to obtain a wear-resistant and shock-absorbing rubber. The present invention uses silicone rubber and modified nano-silica to compound-modify styrene-butadiene rubber, which can not only improve the processing performance of styrene-butadiene rubber and increase the kneading efficiency, but also effectively enhance the shock-absorbing effect and wear-resistant performance of the composite rubber as a whole. Description of the drawings

[0024] Figure 1 It is a characterization diagram of the modified nano-silica of the present invention. Detailed implementation manners

[0025] Next, in combination with the embodiments of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present invention.

[0026] Example 1

[0027] A modified nano-silica is prepared by the following steps:

[0028] First step: After drying 5 g of nano-silica overnight in an oven at 100 °C, it is added to a three-necked flask containing 150 mL of anhydrous toluene. A condenser and a thermometer are installed, and magnetic stirring is started. Then, 2 g of γ-glycidoxypropyltrimethoxysilane is added to the three-necked flask, and the reaction is carried out at 80 °C for 6 h. After the reaction is completed, the solid is filtered out, and the obtained solid is washed with anhydrous ethanol and dried to obtain silane coupling agent-modified nano-silica;

[0029] Second step: The silane coupling agent-modified nano-silica obtained in the first step, 2 g of N-tert-butyl-2-benzothiazole sulfenamide, and 150 mL of anhydrous toluene are mixed in a three-necked flask. A condenser and a thermometer are installed, and magnetic stirring is started. Nitrogen is introduced into the three-necked flask to exhaust the air in the flask, and then the reaction is carried out at 90 °C for 4 h. After the reaction is completed, the solid is filtered out, and the obtained solid is washed with anhydrous ethanol and dried to obtain modified nano-silica.

[0030] Example 2

[0031] A modified nano-silica is prepared by the following steps:

[0032] First step: After drying 5 g of nano-silica overnight in an oven at 100 °C, it is added to a three-necked flask containing 175 mL of anhydrous toluene. A condenser and a thermometer are installed, and magnetic stirring is started. Then, 2.5 g of γ-glycidoxypropyltrimethoxysilane is added to the three-necked flask, and the reaction is carried out at 85 °C for 6 h. After the reaction is completed, the solid is filtered out, and the obtained solid is washed with anhydrous ethanol and dried to obtain silane coupling agent-modified nano-silica;

[0033] Second step: The silane coupling agent-modified nano-silica obtained in the first step, 2.4 g of N-tert-butyl-2-benzothiazole sulfenamide, and 175 mL of anhydrous toluene are mixed in a three-necked flask. A condenser and a thermometer are installed, and magnetic stirring is started. Nitrogen is introduced into the three-necked flask to exhaust the air in the flask, and then the reaction is carried out at 95 °C for 4 h. After the reaction is completed, the solid is filtered out, and the obtained solid is washed with anhydrous ethanol and dried to obtain modified nano-silica.

[0034] Example 3

[0035] A modified nano-silica is prepared by the following steps:

[0036] First step: After drying 5 g of nano-silica overnight in an oven at 100 °C, it is added to a three-necked flask containing 200 mL of anhydrous toluene. A condenser and a thermometer are installed, and magnetic stirring is started. Then, 3 g of γ-glycidoxypropyltrimethoxysilane is added to the three-necked flask, and the reaction is carried out at 90 °C for 6 h. After the reaction is completed, the solid is filtered out, and the obtained solid is washed with anhydrous ethanol and dried to obtain silane coupling agent-modified nano-silica;

[0037] Second step: The silane coupling agent-modified nano-silica obtained in the first step, 2.8 g of N-tert-butyl-2-benzothiazole sulfenamide, and 200 mL of anhydrous toluene are mixed in a three-necked flask. A condenser and a thermometer are installed, and magnetic stirring is started. Nitrogen is introduced into the three-necked flask to exhaust the air in the flask, and then the reaction is carried out at 100 °C for 4 h. After the reaction is completed, the solid is filtered out, and the obtained solid is washed with anhydrous ethanol and dried to obtain modified nano-silica.

[0038] Experimental Example 1

[0039] The modified nano-silica obtained in Example 1 was characterized by infrared spectroscopy. After pressing with potassium bromide tablets, infrared spectroscopy tests were carried out on a Nicolet 6700 Fourier transform infrared spectrometer produced by Thermo Company in the United States. As Figure 1 shown, a characteristic peak of —OH appears at 3400 - 3200 cm -1 a characteristic peak of hydrogen atoms of the benzene ring appears at 3100 - 3000 cm -1 a characteristic peak of Si—O—Si appears at 1100 - 1000 cm -1 a characteristic infrared peak of C—S single bond appears at 600 - 700 cm -1 indicating that the reaction occurred successfully.

[0040] Example 4

[0041] A preparation method of wear-resistant and shock-absorbing rubber includes the following steps:

[0042] First step: 100 parts of styrene-butadiene rubber and 0.5 part of peptizer SJ-103 are added to an internal mixer. The internal mixing temperature is 60 °C, the stirring speed of the internal mixer is 30 rpm, the pressure of the pressing hammer of the internal mixer is 0.6 MPa, and after stirring for 3 min and mixing, it is left standing for 24 h for standby;

[0043] Step 2: Add 4.5 parts of zinc oxide, 3 parts of stearic acid, 0.3 part of antioxidant RD (TMQ), and 2 parts of coumarone resin into a mixer. The mixing temperature is 60°C, the stirring speed of the mixer is 30 rpm, the pressure of the pressing hammer of the mixer is 0.6 MPa. Stir for 2 min and then plasticize for 1 min. After that, add 25 parts of silicone rubber and 30 parts of the modified nano-silica obtained in Example 1 into the mixer, and continuously raise the temperature and stir for 6 min during mixing;

[0044] Step 3: Raise the mixing temperature to 130°C, then discharge the rubber to an open mill. After the open milling is completed, cool to room temperature and let it stand for 24 h. Then add the cooled and standing mixed rubber, 1.8 parts of sulfur, and 0.4 part of tetrabenzylthiuram disulfide into the mixer. The stirring speed of the mixer is 30 rpm, the pressure of the pressing hammer of the mixer is 0.6 MPa. Raise the temperature to 70°C and stir for 8 min for mixing. After the mixing is completed, discharge the rubber to an open mill. After the open milling is completed, a wear-resistant and shock-absorbing rubber is obtained.

[0045] Among them, the particle size specification of the modified nano-silica is 10 - 40 nm.

[0046] Example 5

[0047] A preparation method of a wear-resistant and shock-absorbing rubber, comprising the following steps:

[0048] Step 1: Add 100 parts of styrene-butadiene rubber and 1 part of peptizer SJ-103 into a mixer. The mixing temperature is 65°C, the stirring speed of the mixer is 35 rpm, the pressure of the pressing hammer of the mixer is 0.7 MPa. Stir for 4 min and then let it stand for 24 h for standby;

[0049] Step 2: Add 5.5 parts of zinc oxide, 4 parts of stearic acid, 0.4 part of antioxidant RD (TMQ), and 2.5 parts of coumarone resin into a mixer. The mixing temperature is 65°C, the stirring speed of the mixer is 35 rpm, the pressure of the pressing hammer of the mixer is 0.7 MPa. Stir for 3 min and then plasticize for 1 min. After that, add 30 parts of silicone rubber and 35 parts of the modified nano-silica obtained in Example 2 into the mixer, and continuously raise the temperature and stir for 7 min during mixing;

[0050] Step 3: Raise the mixing temperature to 135°C, then discharge the rubber to an open mill. After the open milling is completed, cool to room temperature and let it stand for 24 h. Then add the cooled and standing mixed rubber, 2.2 parts of sulfur, and 0.5 part of tetrabenzylthiuram disulfide into the mixer. The stirring speed of the mixer is 35 rpm, the pressure of the pressing hammer of the mixer is 0.7 MPa. Raise the temperature to 75°C and stir for 9 min for mixing. After the mixing is completed, discharge the rubber to an open mill. After the open milling is completed, a wear-resistant and shock-absorbing rubber is obtained.

[0051] Among them, the particle size specification of the modified nano-silica is 10 - 40 nm.

[0052] Example 6

[0053] A preparation method of wear-resistant and shock-absorbing rubber, comprising the following steps:

[0054] First step: Add 100 parts of styrene-butadiene rubber and 1.5 parts of peptizer SJ-103 into a mixer. The mixing temperature is 70°C, the stirring speed of the mixer is 40 rpm, the pressure of the ram of the mixer is 0.8 MPa, stir for 5 min, mix, and then stand for 24 h for standby;

[0055] Second step: Add 6.5 parts of zinc oxide, 5 parts of stearic acid, 0.5 part of antioxidant RD (TMQ), and 3 parts of coumarone resin into the mixer. The mixing temperature is 70°C, the stirring speed of the mixer is 40 rpm, the pressure of the ram of the mixer is 0.8 MPa, stir for 4 min, mix, and then plastify for 1 min. Then add 35 parts of silicone rubber and 40 parts of the modified nano-silica obtained in Example 3 into the mixer, and continuously raise the temperature and stir for 8 min during the mixing;

[0056] Third step: Raise the mixing temperature to 140°C, then discharge the rubber to an open mill. After the open milling is completed, cool to room temperature and stand for 24 h. Then add the cooled and standing mixed rubber, 2.6 parts of sulfur, and 0.6 part of tetrabenzylthiuram disulfide into the mixer. The stirring speed of the mixer is 40 rpm, the pressure of the ram of the mixer is 0.8 MPa, raise the temperature to 80°C and stir for 10 min to mix. After the mixing is completed, discharge the rubber to an open mill, and a wear-resistant and shock-absorbing rubber is obtained after the open milling is completed.

[0057] Among them, the particle size specification of the modified nano-silica is 10 - 40 nm.

[0058] Comparative Example 1

[0059] A preparation method of wear-resistant and shock-absorbing rubber, comprising the following steps:

[0060] First step: Add 100 parts of styrene-butadiene rubber and 1.5 parts of peptizer SJ-103 into a mixer. The mixing temperature is 70°C, the stirring speed of the mixer is 40 rpm, the pressure of the ram of the mixer is 0.8 MPa, stir for 5 min, mix, and then stand for 24 h for standby;

[0061] Step 2: Add 6.5 parts of zinc oxide, 5 parts of stearic acid, 0.5 part of antioxidant RD (TMQ), and 3 parts of coumarone resin into a mixer. The mixing temperature is 70°C, the stirring speed of the mixer is 40 rpm, the pressure of the pressing hammer of the mixer is 0.8 MPa. Stir for 4 min and then plasticize for 1 min. After that, add 35 parts of silicone rubber and 40 parts of nano-silica into the mixer, and continuously mix and heat up while stirring for 8 min.

[0062] Step 3: Raise the mixing temperature to 140°C, then discharge the rubber to an open mill. After the open milling is completed, cool it to room temperature and let it stand for 24 h. Then add the cooled and standing mixed rubber, 2.6 parts of sulfur, and 0.6 part of tetrabenzylthiuram disulfide into the mixer. The stirring speed of the mixer is 40 rpm, the pressure of the pressing hammer of the mixer is 0.8 MPa. Heat up to 80°C and stir for 10 min to mix. After the mixing is completed, discharge the rubber to an open mill, and a wear-resistant and shock-absorbing rubber is obtained after the open milling is completed.

[0063] Among them, the particle size specification of the nano-silica is 10 - 40 nm.

[0064] Comparative Example 2

[0065] This comparative example is a commercially available automotive shock-absorbing rubber.

[0066] Experimental Example 2

[0067] Conduct damping performance tests and wear resistance performance tests on the wear-resistant and shock-absorbing rubber obtained in Examples 4 - 6 and Comparative Example 1 and the automotive shock-absorbing rubber in Comparative Example 2 respectively. Damping performance test conditions: frequency 1 Hz, temperature 25°C, strain range 50 - 100%. The wear resistance performance test is carried out with reference to the national standard GB / T9867-2008 "Determination of Abrasion Resistance of Vulcanized Rubber or Thermoplastic Rubber". The test results are shown in Table 1:

[0068] Table 1

[0069] Project Loss factor tanδ <![CDATA[Loss (mm 3 )]]> Example 4 0.394 68 Example 5 0.412 64 Example 6 0.406 76 Comparative Example 1 0.296 86 Comparative Example 2 0.318 126

[0070] It can be seen from Table 1 that the loss factor tanδ of the wear-resistant and shock-absorbing rubber of the present invention in Examples 4 - 6 is higher than that of the commercially available wear-resistant and shock-absorbing rubber in Comparative Example 2, indicating that the wear-resistant and shock-absorbing rubber of the present invention has better shock-absorbing performance. The loss is lower than that of the wear-resistant and shock-absorbing rubber in Comparative Example 2, indicating that the wear-resistant and shock-absorbing rubber of the present invention has better wear resistance.

[0071] The above has introduced in detail a preparation method of a wear-resistant and shock-absorbing rubber provided by the present invention. Specific examples are used in this article to elaborate on the principle and implementation manner of the present invention. The description of the above embodiments is only used to help understand the method and its core idea of the present invention, including the best mode, and also enables any person skilled in the art to practice the present invention, including manufacturing and using any device or system, and implementing any combined method. It should be noted that for those of ordinary skill in the art in this technical field, without departing from the principle of the present invention, several improvements and modifications can be made to the present invention. In particular, as long as there is no structural conflict, the various features in the embodiments disclosed by the present invention can be combined with each other in any way. The reason for not exhaustively describing these combinations in this specification is only to save space and resources. Therefore, the present invention is not limited to the specific embodiments disclosed in the text, but includes all technical solutions falling within the scope of the claims.

Claims

1. A method for preparing wear-resistant and shock-absorbing rubber, characterized in that: The following steps are involved: The first step is to dry the nano-silica at 100°C overnight, add it into a container filled with anhydrous toluene, stir it evenly, add γ-glycidyloxypropyltrimethoxysilane into the container, and react it at 80-90°C for 6h to obtain silane coupling agent modified nano-silica; Step 2: Mix the silane coupling agent modified nano-silica, N-tert-butyl-2-benzothiazole sulfenamide and anhydrous toluene in a container, stir evenly, introduce nitrogen into the container to exhaust the air in the container, and then react at a temperature of 90-100° C. for 4 hours to obtain modified nano-silica; Step 3: Add styrene-butadiene rubber and peptizer into a mixer at a mixing temperature of 60-70°C, stir for 3-5 minutes, and then let stand for 24 hours for use; Step 4: Add zinc oxide, stearic acid, antioxidant and coumarone resin into the internal mixer at a mixing temperature of 60-70°C, stir for 2-4 minutes and then plasticize for 1 minute. Then add silicone rubber and modified nano-silica into the internal mixer, continue mixing and heating for 6-8 minutes. The fifth step is to increase the mixing temperature to 130-140°C, then discharge the rubber into an open mixer. After the mixing is completed, cool to room temperature and let stand for 24 hours. Then, add the cooled and stationary mixed rubber, sulfur and accelerator into the internal mixer, increase the temperature to 70-80°C and stir for 8-10 minutes to mix. After the mixing is completed, discharge the rubber into the open mixer. After the mixing is completed, a wear-resistant and shock-absorbing rubber is obtained.

2. The method for preparing a wear-resistant and shock-absorbing rubber according to claim 1, characterized in that: The peptizer is peptizer SJ-103.

3. The method for preparing the wear-resistant and shock-absorbing rubber according to claim 1, characterized in that: The antioxidant is antioxidant RD (TMQ).

4. The method for preparing a wear-resistant and shock-absorbing rubber according to claim 1, characterized in that: The accelerator is tetrabenzylthiuram disulfide.

5. The method for preparing the wear-resistant and shock-absorbing rubber according to claim 1, characterized in that: The specification of the nano silicon dioxide is 10-40nm.

6. The method for preparing a wear-resistant and shock-absorbing rubber according to claim 1, characterized in that: The dosage ratio of nano silicon dioxide, anhydrous toluene and γ-glycidyloxypropyltrimethoxysilane used in the first step is 5g:150-200mL:2-3g.

7. The method for preparing a wear-resistant and shock-absorbing rubber according to claim 1, characterized in that: The amount ratio of N-tert-butyl-2-benzothiazole sulfenamide and anhydrous toluene used in the second step is 2-2.8 g: 150-200 mL.

8. The method for preparing a wear-resistant and shock-absorbing rubber according to claim 1, characterized in that: The stirring speed of the internal mixer is 30-40 rpm.

9. The method for preparing a wear-resistant and shock-absorbing rubber according to claim 1, characterized in that: The hammer pressure of the internal mixer is 0.6-0.8MPa.

10. The method for preparing the wear-resistant and shock-absorbing rubber according to claim 1, characterized in that: Calculated by weight, the weight of each raw material used in the third, fourth and fifth steps is: 100 parts of styrene-butadiene rubber, 0.5-1.5 parts of peptizer, 4.5-6.5 parts of zinc oxide, 3-5 parts of stearic acid, 0.3-0.5 parts of antioxidant, 2-3 parts of coumarone resin, 25-35 parts of silicone rubber, 30-40 parts of modified nano-silicon dioxide, 1.8-2.6 parts of sulfur, and 0.4-0.6 parts of accelerator.

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