High-wet-grip low-rolling-resistance tread rubber based on octavinyl POSS (Polyhedral Oligomeric Silsesquioxane) modification and preparation method thereof

Abstract

The invention discloses high-wet-grip low-rolling-resistance tread rubber based on octavinyl POSS modification and a preparation method thereof.The rubber prepared according to the formula of the tread rubber can improve an internal cross-linked network of a rubber material, induce distribution of white carbon black and improve the uniformity of the rubber material; furthermore, the tear resistance, the mechanical performance and the wet grabbing performance of the rubber material are enhanced, the durable driving performance and the safe driving performance of the tire are ensured, and the risks that the tire is possibly subjected to large-amplitude tread abrasion in the using process and the tire slips in the driving process are reduced.

Description

Technical Field

[0001] The invention relates to the field of tires, in particular to a high wet grip and low rolling resistance tread rubber based on octaethylene POSS modification and a preparation method thereof. Background Art

[0002] The tread is the part of the tire that comes into direct contact with the ground. Its main functions are to prevent mechanical damage to the tire body, transmit vehicle traction and braking force, and cushion the impact of the tire during driving. Therefore, the tread is required to have good wear resistance, puncture resistance, tear resistance, good elasticity and grip on the ground. Rolling resistance and grip are often on opposite sides.

[0003] Natural rubber, styrene-butadiene rubber and synthetic rubber materials such as butadiene rubber are the main base materials for manufacturing tread rubber. The reinforcing agents are mainly carbon black and white carbon black. At the same dosage, white carbon black has better wet grip performance and lower rolling resistance, so it is often used in the formulation of semi-steel radial tires to fill the tiny pores and defects in the rubber. However, the interfacial bonding force between white carbon black and the rubber matrix is ​​weak, and agglomeration is prone to occur during the mixing process, resulting in uneven distribution, affecting its processing and reinforcement performance. Invention patents such as CN104262713A, CN107903458A, and CN106349527A disclose that white carbon black is added to rubber as a filler to enhance the wear resistance and other properties of the rubber. At the same time, white carbon black dispersant and silane coupling agent are used together to make it better processed and dispersed.

[0004] In order to better balance the various properties of the tread rubber, we optimize the configuration of octaethylene-POSS as a tread rubber modifier and white carbon black dispersant to ensure low rolling resistance while improving wet grip and tear resistance. Summary of the invention

[0005] The purpose of the present invention is to provide a high wet grip and low rolling resistance tread rubber based on octavinyl POSS modification and a preparation method thereof in order to solve the above problems. The prepared tire rubber has good grip, anti-skid properties, low rolling resistance and tear resistance.

[0006] The present invention achieves the above-mentioned purpose through the following technical solutions:

[0007] The invention provides a high wet grip and low rolling resistance tread rubber formula based on octavinyl POSS modification, which comprises 70-90 phr of high ethylene styrene-butadiene rubber (vinyl content is not less than 65%), 10-30 phr of butadiene rubber, 20-20 phr of carbon black N3300, 70-90 phr of white carbon black 165MP, 20-30 phr of environmentally friendly aromatic oil, 0-5 phr of white carbon black dispersant, 7-12 phr of silane coupling agent 747, 0-6 phr of octavinyl POSS, 1-3 phr of protective wax, 2-5 phr of zinc oxide, 1-3 phr of stearic acid, 1-3 phr of 6PPD antioxidant, 1-3 phr of antioxidant RD and 3.8 phr of vulcanization system.

[0008] As a preferred embodiment of the present invention, a high wet grip and low rolling resistance tread rubber formula based on octavinyl POSS modification includes 80phr of high-ethylene styrene-butadiene rubber (vinyl content ≥65%); 20phr of butadiene rubber; 8phr of carbon black N330; 80phr of white carbon black 165MP; 25phr of environmentally friendly aromatic oil; 3phr of white carbon black dispersant; 9phr of silane coupling agent 747; 3phr of octavinyl POSS; 1.5phr of protective wax; 2phr of zinc oxide; 2phr of stearic acid; 2phr of 6PPD antioxidant; 1phr of antioxidant RD; and 3.8phr of vulcanization system.

[0009] As a preferred embodiment of the present invention, the vulcanization system includes accelerator CBS, sulfur, scorch retarder CTP and accelerator DPG.

[0010] The present invention also provides a method for preparing a high wet grip and low rolling resistance tread rubber based on octavinyl POSS modification, comprising the following steps:

[0011] Step S1, one-stage mixing: the initial temperature is 60° C., the mixing time is 5 min, raw rubber, 3 / 5 reinforcing filler, silane coupling agent, the remaining 2 / 5 reinforcing filler, cyclohexane oil and small materials except the vulcanization system are added in sequence for one-stage mixing, and a first-stage mixed rubber is obtained after cleaning and degumming;

[0012] Step S2, second stage mixing: the initial temperature is 70° C., the mixing time is 1 min, the first stage mixed rubber, sulfur, scorch retarder and accelerator are added in sequence for second stage mixing, and the second stage mixed rubber is obtained after the rubber is discharged;

[0013] Step S3, the second-stage mixed rubber is rolled into triangle packages on an open mixing mill for three times, and the rubber is left to stand for 24 hours to obtain a vulcanized rubber.

[0014] As a preferred embodiment of the present invention, the internal mixer is ML-1.5L.

[0015] As a preferred embodiment of the present invention, the rotor speed of the internal mixer is 60r / min.

[0016] The beneficial effects of the present invention are as follows: the rubber prepared by the formula of the rubber of the present invention can improve the internal cross-linking network of the rubber, induce the distribution of white carbon black and improve the uniformity of the rubber, further manifested in enhancing the tear resistance, mechanical properties and wet grip performance of the rubber, ensuring the durable driving performance and safe driving performance of the tire, and reducing the risk of significant tread wear and slipping during driving of the tire during use. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is a comparison diagram of the carbon black analyzer rubber imaging before and after adding octavinyl POSS of the present invention. DETAILED DESCRIPTION

[0018] In order to make the objectives, technical solutions and advantages of the present invention clearer, the implementation method of the present invention will be described in detail below in conjunction with the accompanying drawings and embodiments, so that the implementation process of how the present invention applies technical means to solve technical problems and achieve technical effects can be fully understood and implemented accordingly.

[0019] In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention may also be implemented in other ways different from those described herein. Therefore, the protection scope of the present invention is not limited to the specific embodiments disclosed below.

[0020] The present invention will be further described below in conjunction with specific embodiments.

[0021] The raw material ratios of each component of the embodiments and comparative examples are shown in Table 1.

[0022] Preparation method of tread rubber of embodiment and comparative example:

[0023] The formula uses an internal mixer ML-1.5L + an open mixer. The mixing method in the internal mixer adopts a two-stage mixing process, all of which are carried out in the internal mixer, and the rotor speed is 60r / min. The initial temperature of the first stage of mixing is 60℃, the mixing time is 5min, and the order of adding materials is: raw rubber→3 / 5 reinforcing filler, silane coupling agent→the remaining 2 / 5 reinforcing filler, cyclohexane oil and small materials except the vulcanization system→sweeping→drying; the initial temperature of the second stage of mixing is 70℃, the mixing time is 1min, and the order of adding materials is: first stage mixed rubber→sulfur, anti-scorch agent and accelerator→drying. The mixed rubber is triangularly packaged on the open mixer and repeated three times. After the rubber is left to stand for 24h, rheological tests are carried out and the rubber is vulcanized.

[0024] Table 1 Raw material ratios of the embodiments and comparative examples

[0025]

[0026] The rubber obtained in the embodiment and the comparative example was tested by a thermal dynamic analyzer DMA, and the test items included tanδ at 0°C and tanδ at 60°C. The Shore hardness, tensile strength, elongation, elongation, DIN, and Akron abrasion of the rubber were tested;

[0027] Shore hardness test standard GB / T 531.1-2008 / ISO 7619-1;

[0028] Tensile strength, elongation and tensile strength test standard (HB / T 2198-2011);

[0029] Carbon black analyzer GT-505-CBD1.

[0030] The test results of the rubber properties of the embodiments and comparative examples are shown in Table 2.

[0031] Table 2 Rubber properties of the embodiments and comparative examples

[0032]

[0033] From the comparison in Table 2, we can see the improvement effect of adding octaethylene POSS: 1. Trouser tearing is increased from 20.2MPa to 31.0MPa, and right-angle tearing is increased from 49.0MP to 54.8MP;

[0034] 2. Under the condition of maintaining low rolling resistance (tanδ<0.1 at 60℃), wet grip performance: tanδ at 0℃ increased from 0.1824 to 0.3413;

[0035] 3. Mooney ML (1+4) at 100℃ drops from 74 to 69, and the hardness of the rubber drops from 76 to 73, with better processing performance;

[0036] 4. The tensile strength and elongation of rubber are both improved, with the strength increased from the current 15.7MPa to 18.5MPa; the elongation is increased from 576% to 658%.

[0037] Table 3 Rubber imaging results of Example 3 and Comparative Example 3

[0038] project Comparative Example 3 Example 3 Total number of particles 311 341 Maximum particle diameter (um) 43.441 32.009 Total particle area (um^2) 33474 23376 Average ion area (um^2) 107.6 68.5 Average ion diameter 9.45 7.41 Classification CB(X) 2.14 4.12 Classification CB(Y) 6.34 8.42

[0039] As attached Figure 1 As shown, Figure 1 a is the source image without adding octaethylene-POSS rubber; Figure 1 b is the image of the sample with octaethylene-POSS rubber; Figure 1c is the image of the analyzer comparing the samples. At the same magnification, the inside of the rubber compound with the addition of octaethylene-POSS is observed. The particle size distribution is more (341) and the total particle area is smaller (23376um^2). The average particle size, average area and diameter are smaller (68.5um^2 and 7.41um^2), and the classification on the Y axis is larger (8.42). This is enough to show that the introduction of octaethylene-POSS into the base rubber can better disperse the white carbon black and make it more evenly distributed.

[0040] Although the present invention is described herein with reference to the illustrative embodiments of the present invention, the above embodiments are only preferred embodiments of the present invention, and the embodiments of the present invention are not limited to the above embodiments. It should be understood that those skilled in the art can design many other modifications and embodiments, which will fall within the scope and spirit of the principles disclosed in this application.

Claims

1. A high wet grip low rolling resistance tread rubber based on octavinyl POSS modification, characterized in that: Including high-ethylene styrene-butadiene rubber (vinyl content ≥65%) 70-90phr; butadiene rubber 10-30phr; carbon black N3300-20phr; white carbon black 165MP70-90phr; environmentally friendly aromatic oil 20-30phr; white carbon black dispersant 0-5phr; silane coupling agent 747 7-12phr; octavinyl POSS 0-6phr; protective wax 1-3phr; zinc oxide 2-5phr; stearic acid 1-3phr; 6PPD antioxidant 1-3phr; antioxidant RD1-3phr; vulcanization system 3.8phr.

2. A high wet grip low rolling resistance tread rubber based on octavinyl POSS modification according to claim 1, characterized in that: Including high vinyl styrene butadiene rubber (vinyl content ≥ 65%) 80phr; butadiene rubber 20phr; carbon black N330 8phr; white carbon black 165MP 80phr; environmentally friendly aromatic oil 25phr; white carbon black dispersant 3phr; silane coupling agent 747 9phr; octavinyl POSS 3phr; protective wax 1.5phr; zinc oxide 2phr; stearic acid 2phr; 6PPD antioxidant 2phr; antioxidant RD 1phr; Curing system 3.8phr.

3. A high wet grip low rolling resistance tread rubber based on octavinyl POSS modification according to claim 1, characterized in that: The vulcanization system comprises accelerator CBS, sulfur, scorch retarder CTP and accelerator DPG.

4. A method for preparing a high wet grip low rolling resistance tread rubber based on octavinyl POSS modified according to any one of claims 1 to 3, comprising the steps of: Step S1, one-stage mixing: the initial temperature is 60° C., the mixing time is 5 min, raw rubber, 3 / 5 reinforcing filler, silane coupling agent, the remaining 2 / 5 reinforcing filler, cyclohexane oil and small materials except the vulcanization system are added in sequence for one-stage mixing, and a first-stage mixed rubber is obtained after cleaning and degumming; Step S2, second stage mixing: the initial temperature is 70° C., the mixing time is 1 min, the first stage mixed rubber, sulfur, scorch retarder and accelerator are added in sequence for second stage mixing, and the second stage mixed rubber is obtained after the rubber is discharged; Step S3, the second-stage mixed rubber is rolled into triangle packages on an open mixing mill for three times, and the rubber is left to stand for 24 hours to obtain a vulcanized rubber.

5. a kind of preparation method of high wet grip low rolling resistance tread rubber based on octavinyl POSS modification according to claim 4, it is characterized in that: The internal mixer is ML-1.5L.

6. a kind of preparation method of high wet grip low rolling resistance tread rubber based on octavinyl POSS modification according to claim 4, it is characterized in that: The rotor speed of the internal mixer is 60r / min.

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