阅读说明：本技术 一种缺气保用轮胎支撑胶用胶料及其制备方法和缺气保用轮胎 (Sizing material for run-flat tire support rubber, preparation method of sizing material and run-flat tire ) 是由 周荣杰 王志远 曹晖 李键 何顺雄 邱艳舞 于 2019-10-28 设计创作，主要内容包括：本发明涉及橡胶技术领域,尤其涉及一种缺气保用轮胎支撑胶用胶料及其制备方法和缺气保用轮胎。本发明公开了一种缺气保用轮胎支撑胶用胶料,包括以下组分：基体橡胶、填料、活性剂、防老剂、树脂、硫化剂、促进剂和多功能交联助剂；基体橡胶为天然橡胶和顺丁橡胶。本发明中,树脂和多功能交联助剂的加入,使得硫化剂和促进剂的用量减少,进而使得本发明缺气保用轮胎支撑胶用胶料具有高定伸强度、高模量,耐高温,同时兼顾优异加工性能和抗硫化返原性能。(The invention relates to the technical field of rubber, in particular to a rubber material for a run-flat tire support rubber, a preparation method of the rubber material and a run-flat tire. The invention discloses a rubber material for a run-flat tire support rubber, which comprises the following components: matrix rubber, filler, an active agent, an anti-aging agent, resin, a vulcanizing agent, an accelerator and a multifunctional crosslinking auxiliary agent; the matrix rubber is natural rubber and butadiene rubber. According to the invention, the addition of the resin and the multifunctional crosslinking assistant reduces the consumption of the vulcanizing agent and the accelerator, so that the rubber material for the run-flat tire support rubber has high stretching strength, high modulus and high temperature resistance, and simultaneously has excellent processability and reversion resistance.)

1. A rubber material for a run-flat tire support rubber is characterized by comprising the following components:

matrix rubber, filler, an active agent, an anti-aging agent, resin, a vulcanizing agent, an accelerator and a multifunctional crosslinking auxiliary agent;

the matrix rubber is natural rubber and butadiene rubber;

the filler is carbon black, white carbon black, calcium carbonate and/or argil.

2. The compound according to claim 1, wherein the base rubber is 100 parts by weight;

40-80 parts of a filler;

3-11 parts of active agent

1-6 parts of an anti-aging agent;

0.5-3 parts of resin;

1-4 parts of a vulcanizing agent;

1-5 parts of an accelerator;

0.5-2 parts of multifunctional crosslinking assistant.

3. The compound according to claim 1, wherein the base rubber is 100 parts by weight;

50-70 parts of a filler;

4-9 parts of active agent

2-5 parts of an anti-aging agent;

1-2 parts of resin;

2-4 parts of a vulcanizing agent;

2-4 parts of an accelerator;

0.5-1 part of multifunctional crosslinking assistant.

4. A compound according to claim 1, characterised in that the butadiene rubber is selected from neodymium-based butadiene rubber and/or nickel-based butadiene rubber;

the cis-butadiene rubber has a cis-potential content of more than 96%.

5. A compound according to claim 1, characterised in that the dry rubber of the natural rubber and the dry rubber of the butadiene rubber are in the following weight ratio: (80-40): (20-60).

6. Compound according to any of claims 1 to 5,

the resin is a polyfunctional maleimide compound;

the multifunctional crosslinking assistant is 1, 6-bis (N, N dibenzyl thiocarbamoyl disulfide) alkane;

the accelerant is one or more of an accelerant TBZTD, an accelerant NS and an accelerant CZ;

the active agent is zinc oxide and/or stearic acid;

the vulcanizing agent IS sulfur powder and/or insoluble sulfur IS 7020.

7. The rubber compound according to claim 6, wherein the carbon black has a nitrogen adsorption specific surface area of 20 to 100m²(ii)/g, iodine absorption value is 20-100 g/kg.

8. Process for the preparation of a compound according to any one of claims 1 to 7, characterized in that it comprises the following steps:

step 1: adding matrix rubber, filler, an active agent, an anti-aging agent and resin into an internal mixer for masterbatch to obtain masterbatch;

step 2: and adding a vulcanizing agent, an accelerator and a multifunctional crosslinking assistant into the master batch for final refining to obtain the rubber material.

9. The preparation method of claim 8, wherein the rubber discharging temperature of the primary refining is 160-170 ℃;

and the rubber discharging temperature of the final refining is 105-111 ℃.

10. A run-flat tire comprising a compound according to any one of claims 1 to 7.

Technical Field

The invention relates to the technical field of rubber, in particular to a rubber material for a run-flat tire support rubber, a preparation method of the rubber material and a run-flat tire.

Background

The run-flat tire as a tire with a safety performance is emphasized, and can still run safely at the speed of 80km/h under the condition of unexpected tire burst or zero air pressure, so that the life and property safety of a driver and passengers is guaranteed, and the inconvenience of carrying a spare tire is also saved. Run-flat tires are now widely used, particularly in some high-end and military automotive applications.

The support rubber plays a crucial role as the most critical component in a run-flat tire. The requirements of the formula performance of the support adhesive are high ductility, high modulus, low heat generation, excellent flexibility and high temperature resistance. Therefore, the formula design generally adopts a high-sulfur and high-acceleration vulcanization system to obtain higher tensile strength and modulus, which leads to short scorching time of the rubber compound, high vulcanization speed and poor processability of the rubber compound. Meanwhile, the support rubber is subjected to a higher vulcanization temperature (the actual measurement temperature is over 170 ℃) in the tire vulcanization process, so that the support rubber has a serious vulcanization reversion phenomenon, which is shown in the fact that the hardness of the support rubber measured by the actual tire is usually lower than the design hardness, and the mileage durability of the run-flat tire is affected.

For the formula of the support rubber, the endurance performance of the run-flat tire can be improved to a certain extent by improving the stretching strength and modulus of the rubber, but the stretching strength and modulus are only improved from a vulcanization system, so that the limit is certain.

Disclosure of Invention

The invention provides a rubber material for a run-flat tire support rubber, a preparation method thereof and a run-flat tire, and solves the problems that the conventional rubber material for the run-flat tire support rubber adopts a high-sulfur high-acceleration vulcanization system to improve the tensile strength and modulus, so that the rubber material has poor processing performance and has a serious vulcanization reversion phenomenon.

The specific technical scheme is as follows:

the invention provides a rubber material for a run-flat tire support rubber, which comprises the following components:

matrix rubber, filler, an active agent, an anti-aging agent, resin, a vulcanizing agent, an accelerator and a multifunctional crosslinking auxiliary agent;

the matrix rubber is natural rubber and butadiene rubber;

the filler is carbon black, white carbon black, calcium carbonate and/or argil.

Preferably, the base rubber is 100 parts by weight;

40-80 parts of a filler;

3-11 parts of active agent

1-6 parts of an anti-aging agent;

0.5-3 parts of resin;

1-4 parts of a vulcanizing agent;

1-5 parts of an accelerator;

0.5-2 parts of multifunctional crosslinking assistant.

Preferably, the base rubber is 100 parts by weight;

50-70 parts of a filler;

4-9 parts of active agent

2-5 parts of an anti-aging agent;

1-2 parts of resin;

2-4 parts of a vulcanizing agent;

2-4 parts of an accelerator;

0.5-1 part of multifunctional crosslinking assistant.

Preferably, the butadiene rubber is selected from neodymium butadiene rubber and/or nickel butadiene rubber;

the cis-butadiene rubber has a cis-potential content of more than 96%.

Preferably, the weight ratio of the dry rubber of the natural rubber to the dry rubber of the butadiene rubber is as follows: (80-40): (20-60).

The resin is a polyfunctional maleimide compound;

the multifunctional crosslinking assistant is 1, 6-bis (N, N dibenzyl thiocarbamoyl disulfide) alkane;

the accelerator is one or more of an accelerator TBZTD, an accelerator NS and an accelerator CZ;

the active agent is zinc oxide and/or stearic acid;

the vulcanizing agent IS sulfur powder and/or insoluble sulfur IS 7020.

Preferably, the nitrogen adsorption specific surface area of the carbon black is 20-100 m²(ii)/g, iodine absorption value is 20-100 g/kg.

The invention also provides a preparation method of the rubber compound, which comprises the following steps:

step 1: adding matrix rubber, filler, an active agent, an anti-aging agent and resin into an internal mixer for masterbatch to obtain masterbatch;

step 2: and adding a multifunctional crosslinking assistant, a vulcanizing agent and an accelerator into the master batch for final refining to obtain the rubber material.

Preferably, the rubber discharging temperature of the primary refining is 160-170 ℃;

and the rubber discharging temperature of the final refining is 105-111 ℃.

The invention also provides a run-flat tire comprising the rubber material.

According to the technical scheme, the invention has the following advantages:

the invention provides a rubber material for a run-flat tire support rubber, which comprises the following components: matrix rubber, filler, an active agent, an anti-aging agent, resin, a vulcanizing agent, an accelerator and a multifunctional crosslinking auxiliary agent; the matrix rubber is natural rubber and butadiene rubber.

In the invention, the matrix rubber is a combination of natural rubber and butadiene rubber, and the natural rubber can provide higher strength and modulus; the butadiene rubber has good flexibility and high temperature resistance, and can improve the anti-reversion performance of the rubber material; the addition of the filler can provide enough tensile strength and modulus for the rubber; the resin in the rubber material can participate in the vulcanization process of the rubber material, the stretching strength and modulus can be further improved on the premise of not increasing the heat generation performance, and meanwhile, the scorching time can be greatly prolonged by adding the resin, and the processing performance of the rubber material can be improved; the addition of the resin and the multifunctional crosslinking assistant reduces the dosage of a vulcanizing agent and an accelerator, so that the rubber material for the run-flat tire supporting rubber has high tensile strength, high modulus and high temperature resistance, and simultaneously has excellent processability and reversion resistance.

Detailed Description

The embodiment of the invention provides a rubber material for a run-flat tire support rubber, a preparation method of the rubber material and a run-flat tire, and aims to solve the problems that the conventional rubber material for the run-flat tire support rubber adopts a high-sulfur high-acceleration vulcanization system to improve the tensile strength and modulus, so that the rubber material has poor processing performance and has a serious reversion phenomenon.

In order to make the objects, features and advantages of the present invention more obvious and understandable, the technical solutions in the embodiments of the present invention will be clearly and completely described below, and it should be apparent that the embodiments described below are only a part of the embodiments of the present invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

The invention provides a rubber material for a run-flat tire support rubber, which comprises the following components:

matrix rubber, filler, an active agent, an anti-aging agent, resin, a vulcanizing agent, an accelerator and a multifunctional crosslinking auxiliary agent; the matrix rubber is natural rubber and butadiene rubber.

In the invention, the natural rubber has large molecular weight and wide molecular weight distribution, and can improve better physical property and processing property, but the natural rubber has poor heat resistance and easy vulcanization reversion phenomenon in high-temperature vulcanization. The butadiene rubber has good molecular chain flexibility and good heat resistance, and improves the flex property and the reversion resistance of the rubber material.

The natural rubber of the invention: standard gum # 20, ash < 1.0%; impurities < 0.16%; the volatile content is less than 0.8%; a base rubber for the composition of the present invention; the butadiene rubber is selected from neodymium butadiene rubber and/or nickel butadiene rubber, and the ash content is less than 0.2%; the volatile component is less than 0.8 percent, and the homeopathic content is more than 96 percent.

The weight ratio of the dry rubber of the natural rubber and the dry rubber of the cis-butadiene rubber is preferably as follows: (40-80): (20-60), more preferably (60-80): (20-40).

In the present invention, the filler is preferably carbon black, white carbon, calcium carbonate and/or kaolin, and more preferably carbon black is used as a filler system to exert a reinforcing effect in the rubber compound. Carbon black, although generating a large amount of heat, can provide a high tensile strength and modulus at the same amount; and the natural rubber has better compatibility with the carbon black, thereby being beneficial to the dispersion of the carbon black in a matrix.

The nitrogen adsorption specific surface area of the carbon black is 20-100 m²A/g, preferably from 30 to 70m²A,/g, more preferably 35m²(ii)/g, iodine absorption value is 20-100 g/kg. The larger the nitrogen adsorption specific surface area (N2SA), the smaller the carbon black particle size, and the smaller the carbon black particle size, the more heat generated by the compound. The carbon black adopted by the invention has larger grain diameter and smaller structure degree, thereby reducing the heat generation performance of the rubber material.

The filler in the sizing material is preferably 40-80 parts by weight, more preferably 50-70 parts by weight, and further preferably 65-67 parts by weight. The filler is too low in dosage to provide enough tensile strength and modulus; too high a filler content results in excessive heat generation in the rubber compound.

In the present invention, the resin is preferably a polyfunctional maleimide compound. The resin can participate in the crosslinking reaction of rubber molecular chains in the vulcanization process to form C-C double bonds with better thermal stability, and the stability of the carbon-C double bonds is better than that of polysulfide bonds formed by a vulcanizing agent, so that the modulus and the heat resistance of the rubber compound are further improved. Moreover, the addition of the resin can reduce the dosage of the vulcanizing agent, thereby improving the vulcanization reversion phenomenon. The resin in the compound of the invention is preferably 0.5 to 3 parts by weight, more preferably 1 to 2 parts by weight.

In the invention, the multifunctional crosslinking assistant is preferably 1, 6 bis (N, N dibenzyl thiocarbamoyl disulfide) alkane, the multifunctional crosslinking assistant ensures that a single sulfur bond and a double sulfur bond with better thermal stability are formed in the process of vulcanizing rubber materials, and the thermal stability of the single sulfur bond and the double sulfur bond is better than that of a polysulfide bond formed by a conventional vulcanizing agent, so that the dosage of the vulcanizing agent can be further reduced, and the phenomenon of reversion can be further improved. The multifunctional crosslinking assistant in the rubber compound of the present invention is preferably 0.5 to 2 parts by weight, more preferably 0.5 to 1 part by weight.

The invention also comprises the following common auxiliary agents: anti-aging agent, activator, accelerator and vulcanizing agent. The anti-aging agent is an anti-aging agent RD and/or an anti-aging agent 4020 commonly used in the field, and can delay the aging of a high molecular compound, and the application has no special limitation on the use of the anti-aging agent and only needs to adopt the anti-aging agent well known in the field; the anti-aging agent in the rubber compound is preferably 1 to 6 parts by weight, and more preferably 2 to 5 parts by weight. An agent for increasing the activity of the accelerator, thereby reducing the amount of the accelerator or shortening the vulcanization time; the active agent is preferably zinc oxide and/or stearic acid, and the active agents used in the present application are those well known in the art, and the present application is not particularly limited; the active agent in the sizing material is preferably 3-11 parts by weight, more preferably 4-9.5 parts by weight, and further preferably 8.5-9.5 parts by weight, wherein the mass ratio of zinc oxide to stearic acid is preferably 7: 2.5, 8: 1.5 or 6.5: 2. the accelerator is used for accelerating vulcanization reaction, the accelerator is preferably one or more of an accelerator TBZTD, an accelerator NS and an accelerator CZ, and the accelerator in the rubber compound is preferably 1-5 parts by weight, and more preferably 2-4 parts by weight. And (2) carrying out a crosslinking reaction on a vulcanizing agent and a rubber molecular chain, wherein the vulcanizing agent IS preferably sulfur powder and/or insoluble sulfur IS7020, and IS preferably insoluble sulfur IS7020, and the vulcanizing agent in the rubber compound IS preferably 1-5 parts by weight, and more preferably 2-4 parts by weight.

The invention also provides a preparation method of the rubber compound, which comprises the following steps:

step 1: adding matrix rubber, a filler, an active agent, an anti-aging agent and resin into an internal mixer for masterbatch to obtain masterbatch, wherein the rubber discharge temperature of the masterbatch is 160-170 ℃, and preferably 160 ℃;

step 2: and adding a vulcanizing agent, an accelerator and a multifunctional crosslinking assistant into the master batch for final refining to obtain a rubber material, wherein the rubber discharging temperature of the final refining is 105-111 ℃.

In the invention, the resin is added in the primary refining process to fully play the reinforcing role, and the multifunctional crosslinking auxiliary agent is added in the final refining process.

The run-flat tire support rubber is subjected to higher vulcanization temperature in the tire vulcanization process, and the actual vulcanization temperature can reach 170-180 ℃. Limited by the current vulcanization process, the vulcanization temperature of the positions of the supporting rubber of the upper die and the lower die of the tire has temperature difference (the temperature of the lower die is lower and the temperature of the upper die is higher due to the condensed water). Therefore, the vulcanization reversion degree of the upper and lower die supporting rubber is inconsistent easily in the tire vulcanization process, so that the hardness of the upper and lower die supporting rubber is inconsistent, and the mileage performance of the tire is affected. The addition of the resin and the multifunctional crosslinking assistant can easily generate C-C bonds, single sulfur bonds and disulfide bonds with better heat resistance in the vulcanization process. Greatly improves the anti-reversion performance of the rubber material, and reduces the hardness difference of the upper and lower die supporting rubber materials.

The invention also provides a run-flat tire which comprises the rubber material for the run-flat tire support rubber.

In the invention, the run-flat tire is prepared from the rubber material prepared by the invention through the processes of extruding, forming and vulcanizing. The tire production process is a conventional tire production process well known to those skilled in the art, and the present invention is not particularly limited.

The raw materials used in the examples of the present invention were all commercially available.

The invention provides a rubber material for a run-flat tire support rubber, a preparation method thereof and a run-flat tire.