CN110283364A - A kind of rubber composition and preparation method thereof for safety tread sidewall - Google Patents

Abstract

The invention discloses a rubber composition for the sidewall of a safety tire and a preparation method thereof. The rubber composition comprises the following raw materials in parts by weight: 100 parts of rubber, 0.5-10 parts of polymaleimide, hydrazide or hydrazide 0.1-5 parts of derivatives, 0.5-10 parts of anti-reversion agent, 20-120 parts of reinforcing filler, 1-12 parts of vulcanizing agent, the preparation method is: rubber, polymaleimide, hydrazide or Hydrazide derivatives and reinforcing fillers are added to the internal mixer for mixing and discharging, cooled and left to stand, then adding a vulcanizing agent and an anti-reversion agent for re-mixing and discharging, and vulcanized to obtain a rubber composition product. The rubber composition used in the tire sidewall of the invention not only has low heat generation, but also has high high-temperature rigidity retention rate, strong high-temperature creep resistance and good zero-pressure driving durability of the tire.

Description

A kind of rubber composition for safety tire sidewall and preparation method thereof

technical field

The invention relates to the technical field of rubber, in particular to a rubber composition used for sidewalls of safety tires.

Background technique

At present, with the rapid development of society, vehicles have become people's daily means of transportation, and safety tires, as a tire that can continue to run under zero or low air pressure, are widely used, especially self-supporting safety tires, The sidewall is filled with support rubber that reinforces the sidewall, and it can still support the vehicle to travel more than 80 kilometers at a speed of 80 kilometers per hour after the tire is out of air.

However, when the support type safety tire is running in a deflated state, the deformation of the sidewall portion of the tire increases, a large amount of heat is generated, and the temperature gradually increases, and the maximum temperature can reach more than 180°C. High temperature will cause the rubber polymer to degrade, the chemical cross-linking bond will be broken, and the mechanical properties of the rubber will be lost, which will reduce the performance of the rubber on the sidewall, and the deformation of the tire will increase, resulting in an accelerated increase in the temperature of the sidewall, and the rubber on the sidewall will Under the condition of high compression load for a long time, the sidewall rubber will creep, and the creep will further increase the deformation amount, resulting in accelerated temperature rise. The accelerated temperature rise shortens the normal service time of the sidewall rubber, thereby reducing its durability and leading to tire failure.

Therefore, how to provide a rubber composition that can improve the durability of the support type safety tire, stabilize the rigidity of the sidewall support rubber, the high temperature creep resistance of the sidewall support rubber, and reduce the heat generation of the sidewall support rubber is Problems that those skilled in the art need to solve urgently.

Contents of the invention

In view of this, the present invention provides a rubber composition for a sidewall of a safety tire and a preparation method thereof.

In order to achieve the above object, the present invention adopts the following technical solutions:

The rubber composition used for the sidewall of safety tires comprises the following raw materials in parts by weight: 100 parts of rubber, 0.5-10 parts of polymaleimide, 0.1-5 parts of hydrazide or hydrazide derivatives, and 0.5 parts of anti-reversion agent -10 parts, 20-120 parts of reinforcing filler, 1-12 parts of vulcanizing agent.

The beneficial effects of the present invention are: in the present invention, polymaleimide, hydrazide or hydrazide derivatives are compounded with the anti-reversion agent according to the weight of the present invention. Among them, the use of hydrazide or its derivatives can reduce the heat generation in the working state of the sidewall, thereby further reducing the temperature rise rate during zero-pressure driving; the carbon-carbon cross-linking bond formed by polymaleimide makes the rubber The improved heat resistance of the composition is conducive to maintaining high temperature rigidity and improving the creep problem caused by long-term compression load; the use of anti-reversion agent can slow down the decrease of crosslinking density caused by high temperature. When the composition of the present invention is used in the sidewall of a safety tire, it can significantly improve the rigidity drop at high temperature and the corresponding creep problem.

The above-mentioned rubber components are selected from diene elastomers, including polybutadiene rubber, natural rubber, polyisoprene rubber, styrene-butadiene copolymer rubber, styrene-isoprene-styrene tertiary Segment copolymer rubber and styrene-butadiene-styrene ternary block copolymer rubber or their mixtures. The preferred natural rubber or polyisoprene rubber consumption is 20 to 100 mass parts, and the preferred polybutadiene rubber consumption is 0 to 80 mass parts, by adjusting the compounding quantity of polybutadiene rubber to specific scope (such as natural rubber 80 parts by mass, 20 parts by mass of butadiene rubber), which can reduce the heat generation performance of the rubber composition, and at the same time ensure the necessary flex resistance of the sidewall.

Further, as mentioned above, the rubber composition of the present invention includes the following raw materials in parts by weight: 100 parts of rubber, 1-6 parts of polymaleimide, 0.1-3 parts of hydrazide or hydrazide derivatives, 0.5 parts of anti-reversion agent -5 parts, 20-120 parts of reinforcing filler, 1-12 parts of vulcanizing agent, more preferably 1-4 parts of polymaleimide.

Wherein, in the present invention, the above-mentioned rubber can be selected from diene elastomers, including polybutadiene rubber, natural rubber, polyisoprene rubber, styrene-butadiene copolymer rubber, styrene-isoprene ethylene-styrene ternary block copolymer rubber and styrene-butadiene-styrene ternary block copolymer rubber or mixtures thereof.

As mentioned above, the rubber composition of the present invention further includes the following raw materials in parts by weight: 100 parts of rubber, 1-4 parts of polymaleimide, 0.1-1 part of hydrazide or hydrazide derivatives, 0.5 parts of anti-reversion agent -3 parts, 20-120 parts of reinforcing filler, 3-8 parts of vulcanizing agent.

As mentioned above, the rubber composition of the present invention, further, the rubber can be a diene elastomer;

As mentioned above, the rubber composition of the present invention, further, the rubber can be polybutadiene rubber, natural rubber, polyisoprene rubber, styrene-butadiene copolymer rubber, styrene-isoprene-styrene One or more of the tertiary block copolymer rubber and the styrene-butadiene-styrene ternary block copolymer rubber are mixed.

As mentioned above in the rubber composition of the present invention, further, the rubber includes the following raw materials in parts by weight: 20-100 parts of natural rubber or polyisoprene rubber, and 0.1-80 parts of polybutadiene rubber.

Adopting the above-mentioned further beneficial effects: compounding the natural rubber or polyisoprene rubber and polybutadiene rubber in a specific amount of the present invention can reduce the heat generation performance of the rubber composition, and at the same time ensure the necessary Excellent flex resistance.

As mentioned above, the rubber composition of the present invention further includes the following raw materials in parts by weight: the vulcanizing agent includes the following raw materials in parts by weight: 1-5 parts of sulfur, and 0.5-4 parts of vulcanization accelerator.

As mentioned above, the rubber composition of the present invention further includes the following raw materials in parts by weight: the vulcanizing agent includes the following raw materials in parts by weight: 1.5-3.5 parts of sulfur, and 1-3.5 parts of vulcanization accelerator.

In the above rubber composition, sulfur can be selected from one or a mixture of soluble sulfur, insoluble sulfur, sulfur carrier, etc.; the vulcanization accelerator can be selected from thiazoles, thiurams, sulfenamides, disulfides One or a mixture of carbamates, xanthic acids, guanidines, thioureas, etc.

The ratio between the amount of sulfur used in parts by mass X and the amount of vulcanization accelerator used in parts by mass Y is proportional to the following expression: 0.5≤X/Y≤1.5; in order to ensure sufficient crosslinking density and better thermal stability, sulfur and The ratio of the vulcanization accelerator is 0.8≤X/Y≤1.2, and the total amount of the vulcanization agent is preferably 3 to 8 parts by mass.

Adopt the above-mentioned further beneficial effects: in the present invention, in the vulcanization system, the amount ratio of vulcanization accelerator and sulfur is within the scope of the present invention, possesses sufficient crosslinking density and better thermal stability, so that the rubber composition of the present invention can be used at high temperature Rigid stability and low creep performance.

As mentioned above, the rubber composition of the present invention, further, the hydrazide or hydrazide derivatives are terephthalic hydrazide, adipic acid dihydrazide, sebacyl hydrazide, dodecane dicarboxylic acid dihydrazide, salicyl hydrazide , N'-(1,3-dimethylbutylene)-3-hydroxy-2-naphthohydrazide one or a mixture of several.

As mentioned above, the rubber composition of the present invention, further, the hydrazide or hydrazide derivative is terephthalic hydrazide, adipic acid dihydrazide, salicyl hydrazide, N'-(1,3-dimethylbutylene) -3-Hydroxy-2-naphthohydrazide mixed.

As mentioned above, the rubber composition of the present invention further includes the following raw materials in parts by weight: the anti-reversion agent is 1,3-bis(citraconimidemethyl)benzene, hexamethylene-1,6-dihydrate A mixture of one or more of disodium thiosulfate and 1,6-bis(N,N'-dibenzothiazolecarbamoyldithio)-hexane.

As mentioned above, the rubber composition of the present invention is further selected from 1,3-bis(citraconimidomethyl)benzene (Perkalink 900 or PK900), hexamethylene-1,6-dithiosulfate dihydrate One or a mixture of sodium salt (Duralink HTS or HTS), 1,6-bis(N,N'-dibenzothiazolecarbamoyldithio)-hexane (KA9188 or WY9188), etc. Preferably, 1,3-bis(citraconimidomethyl)benzene and hexamethylene-1,6-dithiosulfate disodium salt dihydrate are used in an amount of 0.5 to 10 parts by mass, preferably 0.5 to 5 parts by mass, More preferably 0.5 to 3 parts by mass.

Further, the reinforcing filler is one or a mixture of white carbon black and carbon black.

Carbon black can be N110, N121, N134, N220, N231, N234, N242, N293, N299, N315, N326, N330, N332, N339, N343, N347, N351, N358, N375, N539, N550, N582, N630, One or a mixture of N642, N650, N683, N754, N762, N765, N774, N787, N907, N908, N990, N991.

The white carbon black can be one or a mixture of fumed white carbon black and precipitated white carbon black.

Furthermore, the specific surface area of white carbon black is 40-260m ² /g, and the specific surface area of carbon black is 20-160m ² /g. More preferably, the specific surface area of white carbon black can be selected to be 60-180m ² /g, and the specific surface area of carbon black can be selected to be 30-120m ² /g.

The amount of carbon black used is 0 to 120 parts by mass, preferably 30 to 80 parts by mass. Specifically, it can be adjusted according to the mechanical performance requirements in the actual use state. Preferably, the use of carbon black materials with large particle size and high structure can achieve higher modulus and lower heat generation.

The polymaleimide structure contains two or more maleimide functional groups. Including the following chemical formula structures, structures shown in chemical formulas 1 and 2:

Wherein R represents an aromatic hydrocarbon group with 6-30 carbon atoms, or an alkane group with 6-30 carbon atoms, or an alkylaromatic hydrocarbon group with 6-30 carbon atoms; and x is an integer of 0-5 ; y is an integer of 0-5.

n is an integer of 0-30.

The maleimide may be a mixture of polymaleimides with different structures. The maleimide is selected from polymaleimide composition (PAPI), N,N'-(methylenediphenyl)bismaleimide (BMI or BDM), N,N' -One or more mixtures of (methylenediphenyl)bismaleimide (HVA-2 or PDM), etc. A polymaleimide composition (PAPI) with a low softening point, easy dispersion, and a high proportion of maleimide functional groups is preferred; preferably 1 to 6 parts by mass, more preferably 1 to 4 parts by mass.

Further, the hydrazide or hydrazide derivative is a mixture of monohydrazide, monohydrazide derivative, bishydrazide and bishydrazide derivative.

The structure shown in chemical formula 3 of monohydrazide and its derivatives:

Wherein, R is any one of an aromatic hydrocarbon group with 6-30 carbon atoms, an alkane group with 6-30 carbon atoms, and an alkylaromatic hydrocarbon group with 6-30 carbon atoms; R1 is hydrogen, Any of an aromatic hydrocarbon group having 6-30 carbon atoms, an alkane group having 6-30 carbon atoms, an alkylaromatic hydrocarbon group having 6-30 carbon atoms, and hydrogen.

Bihydrazide derivatives have the structure shown in Chemical Formula 4:

R is any one of an aromatic hydrocarbon group with 6-30 carbon atoms, an alkane group with 6-30 carbon atoms, and an alkylaromatic hydrocarbon group with 6-30 carbon atoms; R1 is any one with 6-30 carbon atoms Any one of aromatic hydrocarbon group with 6-30 carbon atoms, alkane group with 6-30 carbon atoms, alkylaromatic hydrocarbon group with 6-30 carbon atoms, hydrogen; R2 is any one with 6-30 carbon atoms Any of an aromatic hydrocarbon group, an alkane group having 6-30 carbon atoms, an alkylaromatic hydrocarbon group having 6-30 carbon atoms, and hydrogen.

The above-mentioned hydrazides and derivatives thereof can be specifically selected from isophthalic hydrazide (IDH or DC-02), adipic dihydrazide (ADH), sebacic hydrazide (SDH), dodecane dicarboxylic acid One of dihydrazide (DDH), salicylhydrazide (SAH), N'-(1,3-dimethylbutylene)-3-hydroxy-2-naphthohydrazide (BMH or DC-01), etc. or a mixture of several. The use of hydrazide and its derivatives can reduce the heat generation of the sidewall part in the working state, thereby further reducing the temperature rise rate during zero-pressure driving. Preferably DC-02, ADH, DC-01, SAH, preferably 0.1 to 3 parts by mass, more preferably 0.1 to 1 part by mass in order to maintain good processability.

The rubber composition for the safety tire sidewall of the present invention also includes any one or more of antioxidants, processing aids, zinc oxide, stearic acid, and hardening resins.

When adopting the above mixing, the weight portion of the anti-aging agent is 2 parts, the weight portion of the processing aid is 2 parts, the weight portion of the processing aid is 2 parts, the weight portion of zinc oxide is 2 parts, and the weight portion is 2 parts of stearic acid , Hardening resin weight portion is 2.5 parts.

The anti-aging agent is the anti-aging agent 6PPD of Shandong Yanggu Huatai Chemical Co., Ltd. Zinc oxide is zinc oxide from Zinc Oxide Co., Ltd. Stearic acid is the stearic acid of Sichuan Tianyu Oleochemical Co., Ltd. The vulcanized resin is SP1045 from SI.

The invention also discloses a preparation method of the rubber composition used for the sidewall of the safety tire, comprising the following steps:

Step (1): Weighing each raw material according to the parts by weight of the rubber composition used for the sidewall of a safety tire according to the claims. Add rubber, polymaleimide, hydrazide or hydrazide derivatives and reinforcing fillers into the internal mixer for mixing and discharging to obtain material A; the mixing time can be 2-8 minutes, and the discharging The temperature during feeding can be 140-170°C;

Step (2): Wait for the material A described in step (1) to cool down and let it stand for more than 8 hours, then add a vulcanizing agent and an anti-reversion agent for re-mixing and discharge to obtain material B. The mixing time in the step is 2-8 minutes again;

Step (3): vulcanize the material B in step (2) to obtain a rubber composition product. In this step, the vulcanization temperature is 150° C., and the vulcanization time is 15-60 minutes.

It can be seen from the above-mentioned technical solutions that, compared with the prior art, the rubber composition of the present invention has high heat resistance, is conducive to maintaining high-temperature rigidity, can slow down the decrease in cross-linking density caused by high temperature, and reduces the thickness of the sidewall support rubber. Heat generation can help improve the creep problem caused by long-term compression load, and can effectively enhance the durability of the support type safety tire.

Detailed ways

The following clearly and completely describes the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only some of the embodiments of the present invention, but not all of them. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention.

In this embodiment, 100 parts by mass of diene rubber is selected from a combination of natural rubber and butadiene rubber, wherein 80 parts by mass of natural rubber and 20 parts by mass of butadiene rubber. The natural rubber is selected from No. 20 standard rubber, and the butadiene rubber is selected from Lanxess' high-cis neodymium-based butadiene rubber CB24.

Carbon black was selected from Cabot's N550.

The polymaleimide is selected from Zhangjiagang Otsuka Chemical Co., Ltd., which has a low softening point, is easy to disperse, and has a high proportion of maleimide functional groups. The polymaleimide composition PAPI.

The anti-reversion agent is 1,3-bis(citraconimidomethyl)benzene (Perkalink 900) and 1,6-bis(N,N'-dibenzothiazolecarbamoyl disulfide) from LANXESS - One or a combination of hexane (KA9188).

Hydrazide and its derivatives were selected from isophthalic hydrazide (IDH) produced by Otsuka Chemical Co., Ltd.

What sulfur selects is the insoluble sulfur HDOT 20 of Shandong Yanggu Huatai Chemical Co., Ltd. (effective sulfur content is 80%); What the vulcanization accelerator can select is the sulfenamide accelerator TBBS of Shandong Shangshun Chemical Co., Ltd..

Choose anti-aging agent 6PPD from Shandong Yanggu Huatai Chemical Co., Ltd., choose zinc oxide from Dalian Zinc Oxide Co., Ltd.; choose stearic acid from Sichuan Tianyu Oleochemical Co., Ltd.; choose hardening resin SL-3005 and curing agent from Huaqi Chemical HMT.

The sample preparation process of this example is as follows: first, put natural rubber and butadiene rubber into an internal mixer to fully mix the two kinds of raw rubber, and then add polymaleimide PAPI, sulfur removal, vulcanization accelerator and anti-vulcanization For materials other than the original agent, knead for about 4-6 minutes, and discharge when the temperature is 160°C. After the masterbatch is cooled and parked for more than 8 hours, add sulfur, vulcanization accelerator and anti-reversion agent, mix at a low speed for about 2 to 8 minutes, and then discharge to obtain a rubber composition. After vulcanization at 150°C for 50 minutes, the relevant physical properties were tested.

The test methods and standards of physical properties are as follows:

1. Low heat generation: use the DMA test of Metravib Company, the temperature is 25°C, the frequency is 10Hz, the dynamic deformation is 0.07% to 50%, and the maximum value of the hysteresis loss factor tanδ is in the plane shear mode. Low heat generation = (Comparative Example 2-4, the maximum value of the hysteresis loss factor tanδ of Examples 1-4 ÷ the maximum value of the hysteresis loss factor tanδ of Comparative Example 1) × 100, the smaller the value of low heat generation, the lower the heat generation Sex is better.

2. High-temperature rigidity retention rate: use Metravib’s DMA to test the shear rigidity K1 of the compound at 50°C, and then increase the temperature to 150°C (heating rate 10°C/min) by program, and measure the shear rigidity K2 of the sample again. The ratio of K2/K1 is the rigidity retention rate of the sample under high temperature conditions.

3. High-temperature creep resistance: use Metravib's DMA to test the rubber material and heat it up to 150°C (heating rate 10°C/min), start to apply shear force to the sample, read the sample deformation, and calculate the shear rigidity K1 , continue to maintain the shear compression state for 10 minutes and then read the sample deformation again to calculate the shear rigidity K2, the ratio of K2/K1 is the creep resistance of the sample under high temperature conditions.

4. Tire durability: The run-flat tire (225/50R18) was prepared with the experimental formula, and the tire was subjected to an indoor machine tool mileage test. Under the condition of zero air pressure, drive at a constant speed of 80km/h until the tire is damaged, and record the time for normal driving.

The following table is an embodiment based on the technical guidance of the present invention and a comparative example as a performance comparison.

*The low heat build-up is in the form of an index, and the calculation formula is: (Example/Comparative Example 1)×100. The lower the value, the better the low heat build-up performance.

* The tire durability is in the form of an index, and the calculation formula is: tire durability = (the normal running time of the tire at zero pressure in the embodiment ÷ the normal running time of the tire at zero pressure in Comparative Example 1) × 100, the greater the tire durability value, the zero pressure durability The better the performance.

Based on the above experimental data, comparing Example 1 and Comparative Example 1, it can be seen that the polymaleimide composition PAPI can improve the high-temperature rigidity retention rate of rubber, high-temperature creep resistance and zero-pressure driving durability of tires. Comparing Example 3 with Example 1 and Comparative Example 1, it can be seen that the combined use of the hydrazide compound IDH further improves the low heat generation performance, thereby further improving the zero-pressure driving durability of the tire.

Comparing Example 2, Comparative Example 1, Comparative Example 2, and Comparative Example 3, it can be found that the polymaleimide composition PAPI and the anti-reversion agent KA9188 and PK900 have improved high-temperature rigidity retention and high-temperature creep resistance Effect.

Comparing Example 1 with Comparative Example 4, Comparative Example 5, and Comparative Example 6, it can be seen that when the dosage ratio of sulfur HDOT 20 and accelerator TBBS exceeds the appropriate range, the high-temperature rigidity retention rate decreases significantly, resulting in zero-pressure driving durability of the tire decline. The proportion relationship between the amount of sulfur in parts by weight X and the amount of vulcanization accelerator in parts by weight Y satisfies the following expression: 0.5≤X/Y≤1.5

The above description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the present invention will not be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims (10)

1. a kind of rubber composition for safety tread sidewall, which is characterized in that including following raw material: rubber 100 Part, 0.5-10 parts of polymaleimide, hydrazides or 0.1-5 parts of hydrazide derivatives, 0.5-10 parts of anti-recovery agent, reinforced filling 20-120 parts and 1-12 parts of vulcanizing agent.

2. a kind of rubber composition for safety tread sidewall according to claim 1, which is characterized in that the vulcanization Agent is made of sulphur and vulcanization accelerator, sulfur consumption parts by weight X and vulcanization accelerator dosage parts by weight Y proportionate relationship meet with Lower expression formula: 0.5≤X/Y≤1.5.

3. a kind of rubber composition for safety tread sidewall according to claim 1, which is characterized in that the sulfur resistive Change revert agent be bis- (the lemon Kang Ya amide methyl) benzene of 1,3-, two be hydrated six Asia -1,6- bisthiosulfate disodium salts, 1,6- it is bis- (N, Two sulphur of N'- bisbenzothiazole carbamyl) mixing of one or more of-hexane.

4. a kind of rubber composition for safety tread sidewall according to claim 1, which is characterized in that the Thomas Carry out the chemical formula 1 and 2 that acid imide comprises the following structure formula；

Wherein, R indicates the aromatic hydrocarbyl with 6 to 30 carbon atoms, or the alkyl with 6 to 30 carbon atoms, or Person has the alkyl aromatic alkyl of 6 to 30 carbon atoms, and x and y each independently represent 0 to 5 integer；

Wherein, n indicates the integer of 0-30.

5. a kind of rubber composition for safety tread sidewall according to claim 1, which is characterized in that the reinforcement Filler is the mixing of one or both of white carbon black and carbon black.

6. a kind of rubber composition for safety tread sidewall according to claim 5, which is characterized in that described white The specific surface area of carbon black is 40-260m²/ g, the specific surface area of the carbon black are 20-160m²/g。

7. a kind of rubber composition for safety tread sidewall according to claim 1, which is characterized in that the list acyl Hydrazine and its derivative includes the structure as shown in chemical formula 3；The bishydrazide and its derivative include the structure as shown in chemical formula 4

Wherein, R, R1 respectively indicate the aromatic hydrocarbyl with 6 to 30 carbon atoms, or the alkane with 6 to 30 carbon atoms Alkyl, perhaps the alkyl aromatic alkyl with 6 to 30 carbon atoms or R1 are hydrogen)

Wherein, R, R1, R2 respectively indicate the aromatic hydrocarbyl with 6 to 30 carbon atoms, or with 6 to 30 carbon atoms Alkyl, perhaps R1 is hydrogen to the alkyl aromatic alkyl perhaps with 6 to 30 carbon atoms or R2 is hydrogen.

8. a kind of preparation method of the rubber composition for safety tread sidewall, which comprises the steps of:

Step (1): the parts by weight according to any one of claim 1-7 for the rubber composition on safety tread sidewall weigh each original Material；

Step (2): rubber, polymaleimide, hydrazides or hydrazide derivatives and reinforced filling are added in mixer and are mixed Discharge after refining obtains material A；

Step (3): standing after the material A described in step (2) is cooling, adds vulcanizing agent and anti-recovery agent carries out again Discharge after mixing obtains material B；

Step (4): rubber composition product is obtained after material B described in step (3) is vulcanized.

9. a kind of preparation method of rubber composition for safety tread sidewall according to claim 8, feature It is, it is 2-15 minute that the time is kneaded in the step (2), and temperature is 130-190 DEG C when the discharge.

10. a kind of preparation method of rubber composition for safety tread sidewall according to claim 8, feature It is, the time of repose in the step (3) is greater than 8 hours；Being kneaded the time in the step (3) again is 2-10 minutes；Institute Stating curing temperature in step (4) is 130-190 DEG C, and vulcanization time is 10-100 minutes.