A tire inner liner rubber composition containing bio-based modified pyrolysis carbon black, a mixing method, and a tire

Abstract

The present invention relates to the technical field of tire preparation, and in particular to a tire innerliner rubber composition containing bio-based modified pyrolysis carbon black, a mixing method, and a tire. The tire innerliner rubber composition containing bio-based modified pyrolysis carbon black is added to the tire innerliner rubber composition. The modified pyrolysis carbon black has an increased number of phenolic hydroxyl groups, carbonyl groups, methoxy groups, and carboxyl groups, thereby improving the surface activity of the pyrolysis carbon black. When added to a rubber composition, the pyrolysis carbon black can replace semi-reinforcing carbon black or inorganic fillers. The prepared rubber composition has low heat generation, reduced tire rolling resistance, and reduced carbon emissions.

Description

Technical Field

[0001] The present invention relates to the technical field of tire preparation, and in particular to a tire airtight layer rubber composition containing bio-based modified pyrolysis carbon black, a mixing method and a tire. Background Art

[0002] The disposal of waste tires has become a burden on the country. In order to better recycle waste tires, many manufacturers have already carried out thermal cracking on waste tires and reused the resulting pyrolysis carbon black. As one of the important products of thermal cracking of waste tires, pyrolysis carbon black has high surface ash and carbonaceous sediment content, poor surface activity, large particle size, and low structure. Untreated pyrolysis carbon black is difficult to use in rubber products. Compared with ordinary industrial carbon black, pyrolysis carbon black obtained by high-temperature pyrolysis has more surface carbonaceous sediment, lower activity, high surface ash content, and fewer surface voids. This determines that the reinforcing properties of pyrolysis carbon black are not very strong. To apply it to rubber, it is necessary to modify the pyrolysis carbon black through surface treatment technology using physical and chemical methods. This can improve the utilization value of pyrolysis carbon black, expand the application field of pyrolysis carbon black, improve the application level of pyrolysis carbon black, and achieve environmental protection goals.

[0003] To improve the performance of pyrolysis carbon black, extensive research has been conducted on waste tire thermal cracking technology and pyrolysis carbon black modification methods. A Chinese invention patent (publication number: CN111808449A) discloses a method for modifying tire pyrolysis carbon black, as well as the modified pyrolysis carbon black and tires. However, the process is complex and the results are limited. A Chinese invention patent (publication number: CN113801376A) discloses a dry-process method for preparing pyrolysis carbon black / rubber composites. This method utilizes high-temperature heat treatment to remove ash from the pyrolysis carbon black. After high-temperature graphitization, the pyrolysis carbon black transforms its surface and interior into a more graphite-rich crystalline structure, improving its structure and surface activity, reducing its particle size, and increasing its specific surface area and surface oxygen-containing functional groups. By activating the inert sites of the pyrolysis carbon black, the pyrolysis carbon black strengthens its bond with the rubber, thereby improving its dispersion in the rubber. A Chinese invention patent (publication number: CN110804229A) discloses a method for modifying pyrolysis carbon black, comprising: diluting cellulose slurry with water using stirring and ultrasonication to prepare a diluted cellulose slurry solution; adding pyrolysis carbon black to the diluted cellulose slurry solution, stirring, and grinding to obtain a uniform pyrolysis carbon black / cellulose hybrid material dispersion; and further diluting the resulting pyrolysis carbon black / cellulose hybrid material dispersion with water, stirring, and drying to obtain a hybrid composite material powder, namely the modified pyrolysis carbon black. A Chinese invention patent (publication number: CN110878148A) discloses a method for modifying pyrolysis carbon black, comprising treating the pyrolysis carbon black with a rubber latex. The method provided in this patent utilizes the principles of alkaline washing and polymer encapsulation, dissolving a strong base in the rubber latex to emulsify and adsorb organic impurities on the carbon black into the latex, while dissolving zinc oxide and white carbon black (silicon dioxide) in the strong base. Due to the encapsulation of low molecular weight compounds by rubber polymers, the solid components after drying will be retained in the corresponding polymer materials, thereby cleaning the carbon black, exposing the active points, and restoring the original reinforcing properties.

[0004] A Chinese invention patent (publication number: CN115418024A) discloses a carbon nanotube / carbon black aggregate, a preparation method, and a high-performance tire tread rubber composition. By adding carbon nanotubes to the carbon black production process, the advantageous properties of the carbon nanotubes can be imparted to the carbon black, forming a new type of carbon black / carbon nanotube aggregate. This aggregate can not only maintain the structural advantages of the carbon nanotubes, such as a high aspect ratio and specific surface area, but also effectively reduce the problem of carbon nanotube flying and improve the dispersion of the carbon nanotubes in the rubber matrix. Adding this carbon nanotube / carbon black aggregate to the rubber can significantly improve the physical and mechanical properties of the rubber, while reducing the hysteresis loss and rolling resistance of the rubber without compromising its anti-skid performance.

[0005] A Chinese invention patent application (publication number: CN115851002A) discloses a wet granulation process for improving the strength of pyrolysis carbon black pellets. The process comprises the following raw materials, in parts by weight: 90-95 parts pyrolysis carbon black powder, 0.1-2 parts binder, 0.1-3 parts surfactant, and 0.1-5 parts pore-enlarging agent. The process includes the following steps: S1, preparing a nucleating solution; S2, wetting with high-speed mixed steam; S3, feeding the pelletizer to produce coarse wet pellets; then passing the pelletizer through a second pelletizer, where the nucleating solution is fully atomized and fed into the second pelletizer to produce fine wet pellets; and S4, drying the resulting pellets. The patent also discloses a binder comprising sodium lignin sulfonate. This patent claims to reduce the strength of the pyrolysis carbon black wet granulation product, improve the uniformity of the internal hard core, and reduce its size. However, in this patent, sodium lignin sulfonate is used solely as a binder, intended to bind the pyrolysis carbon black powder and facilitate subsequent pelletization, thereby resolving the technical problem of severe pyrolysis carbon black flyaways during production.

[0006] Natural lignin is an amorphous, aromatic polymer widely found in plants, containing oxyphenylpropanol or its derivatives in its molecular structure. It is primarily found between cellulose fibers in wood tissue, where its primary function is to harden cell walls by forming an interwoven network, providing resistance and support. Lignin molecules contain a variety of reactive functional groups, including conjugated double bonds, aromatic groups, phenolic hydroxyl groups, alcoholic hydroxyl groups, carbonyl groups, methoxyl groups, and carboxyl groups, forming a three-dimensional network. Due to its renewable, biodegradable, non-toxic nature and abundant reserves, it is increasingly used in the rubber additive industry.

[0007] Chinese invention patent applications (publication numbers: CN111748133A, CN112831059A, and CN111533922A), jointly developed by the applicant and Nanjing University of Technology, disclose the use of lignin or modified lignin in the preparation of radial tires. Lignin can fully or partially replace resorcinol and, at the same time, fully or partially replace antioxidants. Compared to existing technologies, the use of biomass-derived lignin or modified lignin to replace or partially replace resorcinol achieves cost reduction and environmental and non-toxic properties. In particular, the use of demethylated modified lignin can effectively improve various rubber properties. Furthermore, lignin, when used as a thermal oxidative aging agent, improves the thermal oxidative aging performance of rubber products, with the aging change rate significantly lower than that of radial tires without lignin.

[0008] The applicant's Chinese invention patent application (publication number: CN114437417A) discloses a high-performance rubber composition for electric bus treads. The compounding formula, calculated per 100 parts by weight of the raw rubber, includes the following components: 50-80 parts natural rubber, 20-50 parts butadiene rubber and / or styrene-butadiene rubber, 45-60 parts carbon black, 0.2-5 parts carbon nanotubes (CNTs), and a CNT dispersant (CNT to CNT dispersant ratio between 1:8 and 5:1). The CNT dispersant is selected from one or more of lignin, sodium lignin sulfonate, and other lignin derivatives. In this patent, lignin serves as a pre-dispersant for the CNTs.

[0009] The applicant's Chinese invention patent application (publication number: CN115558173B) discloses the use of industrial lignin as a cut-resistant additive in the preparation of cut-resistant tire materials. By adding industrial lignin as a cut-resistant additive, this patent improves the cut resistance of rubber materials. This addresses the impact, cut, puncture, and cracking issues faced by conveyor belts, mining truck tires, and off-road vehicle tires in the mining industry.

[0010] The Chinese invention patent application filed by the applicant (publication number: CN115678038A) discloses that by loading zinc into the three-dimensional network structure of lignin, the dispersion of zinc in the rubber matrix can be improved, thereby preventing zinc agglomeration. Secondly, the dispersion of lignin in the rubber matrix is ​​also correspondingly improved. The preparation of the lignin zinc salt complex is applied to tire tread rubber, thereby reducing the rolling resistance of the tire and increasing the service life of the tire while ensuring the wear resistance of the tire.

[0011] The tire's innerliner seals in air and minimizes the amount of air that escapes from the tire. This helps maintain proper inflation pressure, minimizing the side effects of underinflation, such as increased rolling resistance (which reduces fuel efficiency) and reduced tire durability, handling, and driving performance. It also blocks oxygen and moisture from penetrating the innerliner, preventing oxidation of internal tire components and corrosion of steel wires by moisture, extending tire service life. Currently, the polymers used in all-steel tires are primarily bromobutyl and chlorobutyl.

[0012] The Chinese invention patent application filed by the applicant (publication number: CN116199980A, publication date: 2023-06-02) discloses a tire air-inner layer rubber composition, which is prepared by mixing raw materials including the following components based on 100 parts by weight of the rubber component: 40-90 parts of brominated butyl rubber, 10-40 parts of natural rubber, 10-40 parts of epoxidized natural rubber, 10-40 parts of nanoclay, 30-80 parts of carbon black, 0-10 parts of oil plasticizer, 1.0-6.0 parts of tackifying resin, 2.0-20 parts of liquid butyl reclaimed rubber, and 1.0-10 parts of leveling agent; the composition mainly uses liquid butyl rubber or liquid butyl reclaimed rubber obtained by high-temperature cracking to replace oil plasticizers, and uses epoxidized natural rubber to replace part of the brominated butyl, thereby reducing the air permeability coefficient of the air-inner layer formula and improving the air retention performance of the tire. This patent uses liquid butyl rubber or liquid butyl regenerated rubber produced by high-temperature cracking to replace oil plasticizers, but the carbon black still uses conventional carbon black, which cannot be regenerated and recycled, thereby reducing carbon emissions. Summary of the Invention

[0013] In order to solve the above-mentioned technical problems, the purpose of the present invention is to provide a tire air-inner layer rubber composition containing bio-based modified pyrolysis carbon black. The tire air-inner layer rubber composition is added with bio-based modified pyrolysis carbon black. After modification, the pyrolysis carbon black has an increased number of phenolic hydroxyl groups, carbonyl groups, methoxy groups and carboxyl groups, thereby improving the surface activity of the pyrolysis carbon black. When added to the rubber composition, it can replace semi-reinforcing carbon black or inorganic filler. The prepared rubber composition has low heat generation, reduces tire rolling resistance, and reduces carbon emissions.

[0014] In order to achieve the above-mentioned purpose, the present invention adopts the following technical solutions:

[0015] A tire innerliner rubber composition containing bio-based modified pyrolysis carbon black is prepared by mixing the following raw materials in parts by weight:

[0016] Raw rubber 100phr

[0017] Filler 0~20phr

[0018] Modified pyrolysis carbon black 30~70phr

[0019] Leveler 5-10 phr;

[0020] and appropriate amounts of activators, tackifying resins, plasticizers, and vulcanizing agents;

[0021] The modified pyrolysis carbon black is prepared by reacting the following raw materials based on 100 parts by mass of pyrolysis carbon black:

[0022] 100 parts of pyrolysis carbon black;

[0023] 1.0-100 parts of lignin and / or lignin derivatives;

[0024] 0.1-10 parts of carbon black modifier;

[0025] The carbon black modifier is an aminocarboxylic acid, an aminocarboxylic acid ester, a hydrazide and / or a silane coupling agent.

[0026] Preferably, the modified pyrolysis carbon black is prepared by reacting raw materials comprising the following components based on 100 parts by mass of pyrolysis carbon black:

[0027] 100 parts of pyrolysis carbon black;

[0028] 5.0-30 parts of lignin and / or lignin derivatives;

[0029] 0.2-5.0 parts of carbon black modifier.

[0030] As a further preferred embodiment, the modified pyrolysis carbon black is prepared by reacting raw materials including the following components based on 100 parts by mass of pyrolysis carbon black:

[0031] 100 parts of pyrolysis carbon black;

[0032] 8.0-25 parts of lignin and / or lignin derivatives;

[0033] 0.2-2.0 parts of carbon black modifier.

[0034] Preferably, the lignin derivative is a lignin derivative prepared by chemical reactions such as oxidation, reduction, hydrolysis, alcoholysis, acidolysis, methoxylation, carboxylation, photolysis, phthalation, sulfonation, alkylation, halogenation, nitration, polycondensation and / or graft copolymerization of lignin; more preferably, the lignin derivative is one or more of lignin sulfonate, sulfated lignin, hydrochloric acid lignin, periodate lignin and thioglycolic acid lignin.

[0035] Preferably, the aminocarboxylic acid is selected from 3-aminopyrazine-2-carboxylic acid, 2-(3-aminophenyl)benzoic acid, (2S,3R)-3-hydroxy-2-{[(4-methoxyphenyl)sulfonyl]amino}carboxylic acid, 2-acetamidoacrylic acid, 2-amino-5-acetamidobenzoic acid, 1-aminocyclopropanecarboxylic acid, 3-aminopyrazine-2-carboxylic acid, 5,6-diamino-2-pyridinecarboxylic acid, 2-aminocyclopentanecarboxylic acid, 2-ethylmercapto-4-aminopyrimidine-5-carboxylic acid, azobenzenecarboxylic acid, 3-amino-pyrazine-2-carboxylic acid, 4-aminocyclohexanoic acid, p-aminobenzoic acid and one or more of ethyl 4-aminothiazole-5-carboxylate;

[0036] and / or, the aminocarboxylate is the methyl or ethyl ester corresponding to the aminocarboxylic acid, and methyl 6-amino-3-bromopicolinate, ethyl 4-amino-1,2,5-oxadiazole-3-carboxylate, methyl 3-aminopyrazine-2-carboxylate, methyl 2-aminopyrimidine-5-carboxylate or ethyl 2-aminocyclopentane-1-carboxylate;

[0037] and / or, the hydrazide is selected from one or more of salicylic hydrazide, phthalic acid hydrazide, isophthalic acid hydrazide, diformyl hydrazide, adipic acid dihydrazide, tebufenozide, carbohydrazide, diformyl hydrazide, oxaloyl dihydrazide, biotinyl hydrazide, alkyl hydrazide, aromatic hydrazide, 4-hydroxyphenylhydrazide, maleic hydrazide, 3-hydroxyphenylhydrazide, biotinamide caproyl hydrazide, 1,2-diacetyl hydrazide, 3,4-diaminophenylhydrazide and fatty acid hydrazide;

[0038] And / or, the silane coupling agent has the structural formula: YR-Si(OR)3, wherein Y is an organic functional group and SiOR is a siloxy group; preferably, the silane coupling agent is selected from one or more of vinyltriethoxysilane, vinyltrimethoxysilane, vinyltri(β-methoxyethoxy)silane, bis-[γ-(triethoxysilyl)propyl]tetrasulfide, bis-propyltriethoxysilane disulfide, 3-(octylthio)propyltriethoxysilane and n-octyltriethoxysilane.

[0039] Preferably, the preparation method of the modified pyrolysis carbon black comprises the following steps: adding pyrolysis carbon black, lignin and / or lignin derivatives, and a carbon black modifier into a stirred tank, reacting at a temperature of 20-120°C for 0.1-6h, and drying to obtain lignin-modified pyrolysis carbon black; preferably, the modification reaction temperature is 60°C to 100°C, and the reaction time is 3min-60min.

[0040] Preferably, the activator is 1-3 phr of stearic acid, 4-8 phr of tackifying resin, 6-12 phr of plasticizer, 0.5-1.6 phr of sulfur, and 0.5-1.5 phr of vulcanization accelerator; preferably, the plasticizer is aromatic oil and / or naphthenic oil, and the vulcanizing agent is sulfur and zinc oxide; preferably, the raw materials of the tire innerliner rubber composition also include 0.1-0.4 phr of magnesium oxide.

[0041] Preferably, the raw rubber is selected from one or a mixture of natural rubber, brominated butyl rubber, chlorinated butyl rubber and polybutadiene rubber.

[0042] Preferably, the reinforcing material further comprises one or more of carbon black or white carbon black;

[0043] More preferably, the BET specific surface area of ​​the carbon black particles is 20 to 160 m 2 / g, more preferably 40 to 130 m 2 / g, more preferably 50 to 120 m 2 / g; the average secondary particle size of the carbon black particles is preferably 0.05 to 3 μm, more preferably 0.1 to 1.0 μm, and further preferably 0.2 to 0.9 μm; most preferably, the carbon black is a mixture of one or more of N134, N220, N234, N330, N375, N550, and N660;

[0044] More preferably, the BET specific surface area of ​​white carbon black is 50 to 250 m 2 / g, preferably 80 to 210 m 2 / g, more preferably 100 to 190 m 2 / g; the average secondary particle size of silica is preferably 0.04 to 3 μm, more preferably 0.1 to 1 μm, and further preferably 0.2 to 0.7 μm.

[0045] Preferably, the homogenizer is liquid rubber and / or bio-based modified liquid rubber;

[0046] More preferably, the liquid rubber can be the liquid butyl reclaimed rubber disclosed in the Chinese invention patent application (publication number: CN116199980A, publication date: 2023-06-02), which is prepared by high-temperature cracking of scrapped vulcanized bladders and or butyl inner tubes. The rubber polymer content in the liquid butyl reclaimed rubber is 40-80%, the low molecular weight substance content is 5-20%, the carbon black content is 20-40%, and the ML (1+4) Mooney value at 100°C is 10-20.

[0047] Of course, the bio-based modified liquid regenerated rubber that can also be used is prepared by high-temperature reaction of raw materials including the following components in parts by weight:

[0048] 100 parts of recycled rubber and / or rubber powder;

[0049] 1.0-100 parts of lignin and / or lignin derivatives;

[0050] 2,2'-dibenzamidodiphenyl disulfide 0.05-2.0 parts;

[0051] Furthermore, the preparation method of bio-based modified liquid reclaimed rubber includes the following steps: pre-mixing reclaimed rubber and / or rubber powder, lignin and / or lignin derivatives, and 2,2'-dibenzamidodiphenyl disulfide, and extruding them through a screw at high temperature, wherein the screw shearing reaction temperature is 180°C to 380°C and the reaction time is 0.1min-30min, to prepare bio-based compound modified liquid reclaimed rubber; preferably, the screw shearing reaction temperature is 200°C to 350°C, and the reaction time is 1min-15min.

[0052] The above-mentioned rubber powder is rubber powder with a mesh size of 10 to 100, and the reclaimed rubber is reclaimed rubber with a strength of 8-16 MPa; the lignin derivative is a lignin derivative prepared by chemical reactions such as oxidation, reduction, hydrolysis, alcoholysis, acidolysis, methoxylation, carboxylation, photolysis, phthalation, sulfonation, alkylation, halogenation, nitration, polycondensation or graft copolymerization of lignin; preferably, the lignin derivative is one or more of lignin sulfonate, sulfate lignin, hydrochloride lignin, periodate lignin and thioglycolate lignin.

[0053] Of course, the raw materials of the liquid reclaimed rubber may also include: 0.5-5.0 parts of an activator and 1.0-10.0 parts of a processing aid; preferably, 0.8-2.0 parts of an activator and 1.5-5.0 parts of a processing aid. The activator is one or more of unsaturated fatty acid salts, persulfates, permanganates, chlorates, peroxides, and dichromates; and the processing aid is one or more of p-tert-butylphenol formaldehyde tackifying resin, octylphenol formaldehyde tackifying resin, terpene resin, rosin resin, C5 resin, C9 resin, polycyclopentadiene resin, coumarone resin, fatty acids, fatty acid zinc salts, oleic acid, linseed oil, palm oil, soybean oil, and aromatic oil.

[0054] Furthermore, the present invention also discloses a mixing method of the tire inner liner rubber composition, comprising the following steps:

[0055] 1) First stage mixing: Rubber, filler, cracked carbon black, stearic acid and other rubber processing aids are put into an internal mixer and mixed for 30-40 seconds at a speed of 35-45 rpm. The mixture is lifted and pressed every 20-30 seconds. When the temperature of the rubber compound reaches 125-135°C, the rubber is discharged and the flakes are removed. The mixture is cooled at room temperature for 8-12 hours to obtain a first stage masterbatch.

[0056] 2) Final mixing: The masterbatch from step 1), sulfur, accelerator, and zinc oxide are placed in an internal mixer and mixed at a speed of 20-30 rpm. The mixture is lifted and pressed at intervals of 35 seconds, 20 seconds, and 25 seconds. When the temperature of the rubber material reaches 105°C, the rubber material is discharged and the sheet is removed. After cooling, the airtight layer rubber composition is obtained.

[0057] Furthermore, the present invention also discloses a tire, wherein the airtight layer of the tire is produced by vulcanizing the tire airtight layer rubber composition.

[0058] Due to the adoption of the above-mentioned technical scheme, the present invention has the following characteristics: 1. The modification process is simple and easy to operate. After modification, the pyrolysis carbon black has an increased number of phenolic hydroxyl groups, carbonyl groups, methoxy groups and carboxyl groups, which improves the surface activity of the pyrolysis carbon black. When added to the rubber composition, it can replace semi-reinforcing carbon black or inorganic filler. The prepared rubber composition has low heat generation, reduces tire rolling resistance, and reduces carbon emissions; 2. The pyrolysis carbon black with functional groups is added to the rubber compound to improve the reinforcement effect, thereby improving the performance of the rubber composition; 3. A more environmentally friendly method is provided to solve the problem of using pyrolysis carbon black; 4. The technical problem of serious flying of pyrolysis carbon black in the rubber mixing process is solved; 5. The airtight layer of the tire adopts the tire airtight layer rubber composition, and the addition of lignin-modified pyrolysis carbon black forms a network structure, which improves air tightness; 6. Bio-based modified liquid rubber is used instead of a homogenizer or plasticizer, which improves air tightness and viscosity, and solves the problem of easy detachment of the joints of the pure halogenated butyl formula. DETAILED DESCRIPTION

[0059] The present application will be further described below in conjunction with specific embodiments so that those skilled in the art can better understand the present invention and implement it, but the embodiments are not intended to limit the present invention.

[0060] In addition, unless otherwise specified, the preparation processes in the following examples are all conventional means in the prior art in the art, and therefore, they are not described in detail; the parts in the following embodiments are all parts by weight.

[0061] Example 1

[0062] Based on 100 phr of pyrolysis carbon black, 20 phr of lignin, 100 phr of pyrolysis carbon black, and 0.4 phr of modifier aminocarboxylic acid were added into a blender, and the mixture was stirred at 60° C. for 10 minutes and dried at 100° C. to prepare bio-based compound modified pyrolysis carbon black 1.

[0063] Example 2

[0064] Based on 100 phr of pyrolysis carbon black, 20 phr of lignin, 100 phr of pyrolysis carbon black, and 0.4 phr of modifier hydrazide were added into a blender, and the mixture was stirred at 100° C. for 3 minutes and dried at 100° C. to prepare bio-based compound modified pyrolysis carbon black 2.

[0065] Example 3

[0066] Based on 100 phr of pyrolysis carbon black, 20 phr of lignin, 100 phr of pyrolysis carbon black, and 1 phr of modifier silane were added into a blender, and the mixture was stirred at 100° C. for 5 minutes and dried at 100° C. to prepare bio-based compound modified pyrolysis carbon black 3.

[0067] Example 4

[0068] Based on 100 phr of pyrolysis carbon black, 5.0 phr of lignin, 100 phr of pyrolysis carbon black, and 0.2 phr of modifier aminocarboxylic acid were added into a blender, and the mixture was stirred at 60° C. for 10 minutes and dried at 100° C. to prepare bio-based compound modified pyrolysis carbon black 4.

[0069] Example 5

[0070] Based on 100 phr of pyrolysis carbon black, 50 phr of lignin, 100 phr of pyrolysis carbon black, and 5.0 phr of modifier aminocarboxylic acid were added into a blender, and the mixture was stirred at 60°C for 10 minutes and dried at 100°C to prepare bio-based compound modified pyrolysis carbon black 5.

[0071] Comparative Example 1

[0072] Based on 100 phr of pyrolysis carbon black, 100 phr of pyrolysis carbon black and 0.4 phr of modifier aminocarboxylic acid were added into a blender, and the mixture was stirred at 60° C. for 10 minutes and dried at 100° C. to prepare pyrolysis carbon black 6.

[0073] Comparative Example 2

[0074] Based on 100 phr of pyrolysis carbon black, 20 phr of lignin and 100 phr of pyrolysis carbon black were added into a blender, and the mixture was stirred at 60° C. for 10 min and dried at 100° C. to prepare pyrolysis carbon black 7.

[0075] Application Example 1

[0076] This application example is applied to tire innerliners. The pyrolysis carbon blacks in Test Examples 1-5 were modified with the bio-based compounds described in Examples 1-5, respectively. The pyrolysis carbon blacks in Test Examples 6-7 were modified with the pyrolysis carbon blacks described in Comparative Examples 1-2, respectively. Test Example 8 used conventional pyrolysis carbon black. Test Example 9 used the same formula as in Example 1, but added lignin, pyrolysis carbon black, and the modifier aminocarboxylic acid directly as mixing materials to the innerliner rubber composition without undergoing a modification reaction.

[0077] Among them, the homogenizer is bio-based modified liquid rubber. The preparation method of the bio-based modified liquid rubber is as follows: based on 100 phr of rubber powder, 10 phr of lignin, 100 phr of rubber powder, 0.1 phr of 2,2'-dibenzamidodiphenyl disulfide, 1 phr of activator potassium persulfate, and 2 phr of processing aid rosin resin are added into the mixer, and the bio-based compound modified liquid rubber is prepared by screw extrusion at a high temperature of 280°C.

[0078] The specific formula is shown in Table 1.

[0079] Table 1

[0080] project Reference ratio Test Example 1 Test Example 2 Test Example 3 Test Example 4 Test Example 5 Test Example 6 Test Example 7 Test Example 8 Test Example 9 BIIR 100 100 100 100 100 100 100 100 100 100 Carbon black N660 70 Pyrolysis carbon black 70 70 70 70 70 70 70 70 66 stearic acid 2 2.0 2.0 2.0 2.0 2.0 2.0 2.0 2.0 2.0 Tackifying resin 6 6 6 6 6 6 6 6 6 6 Naphthenic oil 10 10 10 10 10 10 10 10 10 10 magnesium oxide 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 Leveler 8 8 8 8 8 8 8 8 8 8 Lignin 0 0 0 0 0 0 0 0 0 4 Aminocarboxylic acid 0 0 0 0 0 0 0 0 0 0.1 sulfur 0.8 0.8 0.8 0.8 0.8 0.8 0.8 0.8 0.8 0.8 Accelerator 1.3 1.3 1.3 1.3 1.3 1.3 1.3 1.3 1.3 1.3 zinc oxide 4.5 4.5 4.5 4.5 4.5 4.5 4.5 4.5 4.5 4.5

[0081] The mixing method of the cushion rubber composition comprises the following steps:

[0082] 1) First-stage mixing: Rubber, filler, cracked carbon black, stearic acid and other rubber processing aids are put into an internal mixer and mixed for 35 seconds at a speed of 40 rpm. The mixture is lifted and pressed every 25 seconds. When the temperature of the rubber compound reaches 130°C, the rubber is discharged and the flakes are removed. The mixture is cooled at room temperature for 8 to 12 hours to obtain a first-stage masterbatch.

[0083] 2) Final mixing: The masterbatch from step 1), sulfur, accelerator, and zinc oxide were placed in an internal mixer and mixed at 25 rpm. The mixture was lifted and pressed at intervals of 35 seconds, 20 seconds, and 25 seconds. When the temperature of the rubber material reached 105°C, the rubber material was discharged and the sheet was removed. After cooling, the innerliner rubber composition was obtained.

[0084] Its physical properties are as follows:

[0085] project Reference ratio Test Example 1 Test Example 2 Test Example 3 Test Example 4 Test Example 5 Test Example 6 Test Example 7 Test Example 8 Test Example 9 M300 3.9 4.1 4.2 4.0 4.1 3.8 3.3 3.5 3.2 3.1 TB 10 10.2 10.5 10.3 10.4 10.1 8.9 9.5 8.2 9.2 <![CDATA[Air tightness (23 °C) 10 -14 cm 2 (Pa·s) -1 > 5.1 4.2 4.5 4.3 4.3 4.7 5.5 5.8 8.3 7.9

[0086] As can be seen from Test Examples 1-5 and Comparative Example 1, the reinforcing effect of bio-modified pyrolysis carbon black is comparable to that of N660, with a slightly improved tensile strength and a significant improvement in airtightness. As can be seen from Test Examples 6-7 and Test Example 1, the modulus and tensile strength TB of the rubber compound decrease when no modifier or lignin is added during the modification process. Comparison of Test Examples 6-7 and the Reference Example shows that the reinforcing effect of pyrolysis carbon black or lignin is not as good as that of N660. As can be seen from Test Example 8 and the Reference Example, the addition of conventional pyrolysis carbon black significantly decreases the modulus M300 and tensile strength, indicating that the unmodified pyrolysis carbon black is not as reinforcing as N660, nor is its airtightness. As can be seen from Test Example 9 and Test Example 1, the addition of modifiers and lignin to the unmodified rubber compound significantly decreases the tensile strength and modulus M300, indicating that the unmodified pyrolysis carbon black is not as reinforcing as N660. Furthermore, the lignin is difficult to disperse in the formulation, which in turn increases the heat generation of the formulation.

[0087] The present invention has developed a friendly method for modifying pyrolysis carbon black, which not only solves the problem of pyrolysis carbon black flying, but also solves the problem of pyrolysis carbon black reinforcement. At the same time, it improves the application of bio-based materials, is environmentally friendly, and has great social value and economic benefits.

[0088] The above is a description of the embodiments of the present invention. The above description of the disclosed embodiments will enable professionals in the field to implement or use the present invention. Various modifications to these embodiments will be apparent to professionals in the field. The general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but should conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A tire innerliner rubber composition containing bio-based modified pyrolysis carbon black, characterized in that: The tire inner liner rubber composition is prepared by mixing the following raw materials in parts by weight: Raw rubber 100phr Filler 0~20phr Modified pyrolysis carbon black 30~70phr Leveler 5-10 phr; And appropriate amounts of activator, tackifying resin, plasticizer, sulfur and vulcanization accelerator; activator is stearic acid 1-3 phr, zinc oxide 1-3 phr, tackifying resin 4-8 phr, plasticizer 6-12 phr, sulfur 2.5-6 phr, vulcanization accelerator 0.5-1.5 phr; The raw rubber is selected from one or a mixture of natural rubber, brominated butyl rubber, chlorinated butyl rubber and polybutadiene rubber; The modified pyrolysis carbon black is prepared by reacting the following raw materials based on 100 parts by mass of pyrolysis carbon black: 100 parts of pyrolysis carbon black; 1.0-100 parts of lignin and / or lignin derivatives; 0.1-10 parts of carbon black modifier; The carbon black modifier is an aminocarboxylic acid, an aminocarboxylate, a hydrazide and / or a silane coupling agent; The preparation method of the modified pyrolysis carbon black comprises the following steps: adding pyrolysis carbon black, lignin and / or lignin derivatives, and a carbon black modifier into a stirred tank, reacting at a temperature of 20-120° C. for 0.1-6 hours, and drying to obtain lignin-modified pyrolysis carbon black; The homogenizer is liquid rubber and / or bio-based modified liquid rubber; the bio-based modified liquid rubber is prepared by reacting the following raw materials at a high temperature of 180° C. to 380° C. in parts by weight: 100 parts of recycled rubber and / or rubber powder; 1.0-100 parts of lignin and / or lignin derivatives; 2,2'-dibenzamidodiphenyl disulfide 0.05-2.0 parts 2. The tire inner liner rubber composition according to claim 1, wherein The modified pyrolysis carbon black is prepared by reacting the following raw materials based on 100 parts by mass of pyrolysis carbon black: 100 parts of pyrolysis carbon black; 5.0-30 parts of lignin and / or lignin derivatives; 0.2-5.0 parts of carbon black modifier.

3. The tire inner liner rubber composition according to claim 1, wherein The modified pyrolysis carbon black is prepared by reacting the following raw materials based on 100 parts by mass of pyrolysis carbon black: 100 parts of pyrolysis carbon black; 8.0-25 parts of lignin and / or lignin derivatives; 0.2-2.0 parts of carbon black modifier.

4. The tire inner liner rubber composition according to any one of claims 1 to 3, characterized in that: Lignin derivatives are lignin derivatives prepared by chemical reactions such as oxidation, reduction, hydrolysis, alcoholysis, acidolysis of methoxyl groups, carboxyl groups, photolysis, phthalation, sulfonation, alkylation, halogenation, nitration, polycondensation and / or graft copolymerization of lignin.

5. The tire inner liner rubber composition according to claim 4, characterized in that: The lignin derivative is one or more of lignin sulfonate, sulfated lignin, hydrochloric acid lignin, periodate lignin and thioglycolic acid lignin.

6. The tire inner liner rubber composition according to any one of claims 1 to 3, characterized in that: The aminocarboxylic acid is selected from one or more of 3-aminopyrazine-2-carboxylic acid, 2-(3-aminophenyl)benzoic acid, (2S,3R)-3-hydroxy-2-{[(4-methoxyphenyl)sulfonyl]amino}carboxylic acid, 2-acetamidoacrylic acid, 2-amino-5-acetamidobenzoic acid, 1-aminocyclopropanecarboxylic acid, 3-aminopyrazine-2-carboxylic acid, 5,6-diamino-2-pyridinecarboxylic acid, 2-aminocyclopentanecarboxylic acid, 2-ethylmercapto-4-aminopyrimidine-5-carboxylic acid, azobenzenecarboxylic acid, 3-amino-pyrazine-2-carboxylic acid, 4-aminocyclohexanoic acid, p-aminobenzoic acid and ethyl 4-aminothiazole-5-carboxylate; and / or, the aminocarboxylate is the methyl or ethyl ester corresponding to the aminocarboxylic acid, and methyl 6-amino-3-bromopicolinate, ethyl 4-amino-1,2,5-oxadiazole-3-carboxylate, methyl 3-aminopyrazine-2-carboxylate, methyl 2-aminopyrimidine-5-carboxylate or ethyl 2-aminocyclopentane-1-carboxylate; and / or, the hydrazide is selected from one or more of salicylic hydrazide, phthalic acid hydrazide, isophthalic acid hydrazide, diformyl hydrazide, adipic acid dihydrazide, tebufenozide, carbohydrazide, diformyl hydrazide, oxaloyl dihydrazide, biotinyl hydrazide, alkyl hydrazide, aromatic hydrazide, 4-hydroxyphenylhydrazide, maleic hydrazide, 3-hydroxyphenylhydrazide, biotinamide caproyl hydrazide, 1,2-diacetyl hydrazide, 3,4-diaminophenylhydrazide and fatty acid hydrazide; And / or, the structural formula of the silane coupling agent is: YR-Si(OR)3, wherein Y is an organic functional group and SiOR is a silaneoxy group.

7. The tire inner liner rubber composition according to claim 6, wherein: The silane coupling agent is selected from one or more of vinyltriethoxysilane, vinyltrimethoxysilane, vinyltri(β-methoxyethoxy)silane, bis-[γ-(triethoxysilyl)propyl]tetrasulfide, bis-propyltriethoxysilane disulfide, 3-(octylthio)propyltriethoxysilane and n-octyltriethoxysilane.

8. The tire inner liner rubber composition according to any one of claims 1 to 3, characterized in that: The modification reaction temperature is 60°C to 100°C, and the reaction time is 3min to 60min.

9. The tire inner liner rubber composition according to any one of claims 1 to 3, characterized in that: The plasticizer is aromatic oil and / or naphthenic oil.

10. The tire inner liner rubber composition according to any one of claims 1 to 3, characterized in that: The raw materials of the tire inner liner rubber composition further include 0.1-0.4 phr of magnesium oxide.

11. The tire inner liner rubber composition according to any one of claims 1 to 3, characterized in that: The filler is one or more of carbon black and white carbon black.

12. The tire inner liner rubber composition according to claim 11, wherein The BET specific surface area of ​​the carbon black particles is 20 to 160 m 2 / g.

13. The tire inner liner rubber composition according to claim 11, wherein The BET specific surface area of ​​the carbon black particles is 40 to 130 m 2 / g.

14. The tire inner liner rubber composition according to claim 11, wherein The BET specific surface area of ​​the carbon black particles is 50 to 120 m 2 / g.

15. The tire inner liner rubber composition according to claim 11, wherein The average secondary particle size of the carbon black particles is 0.05 to 3 μm.

16. The tire inner liner rubber composition according to claim 11, wherein The average secondary particle size of the carbon black particles is 0.1 to 1.0 μm.

17. The tire inner liner rubber composition according to claim 11, wherein: The average secondary particle size of the carbon black particles is 0.2 to 0.9 μm.

18. The tire inner liner rubber composition according to claim 11, wherein The carbon black is a mixture of one or more of N134, N220, N234, N330, N375 and N550.

19. The tire inner liner rubber composition according to claim 11, wherein The BET specific surface area of ​​white carbon black is 50~250m 2 / g.

20. The tire inner liner rubber composition according to claim 11, wherein The BET specific surface area of ​​white carbon black is 80~210m 2 / g.

21. The tire inner liner rubber composition according to claim 11, wherein The BET specific surface area of ​​white carbon black is 100~190m 2 / g.

22. The tire inner liner rubber composition according to claim 11, wherein The average secondary particle size of silica is 0.04 to 3 μm.

23. The tire inner liner rubber composition according to claim 11, wherein The average secondary particle size of silica is 0.1 to 1 μm.

24. The tire inner liner rubber composition according to claim 11, wherein The average secondary particle size of silica is 0.2 to 0.7 μm.

25. The tire inner liner rubber composition according to claim 1, wherein The preparation method of bio-based modified liquid rubber includes the following steps: pre-mixing reclaimed rubber and / or rubber powder, lignin and / or lignin derivatives, and 2,2'-dibenzamidodiphenyl disulfide, and extruding the mixture through a screw at a high temperature, wherein the screw shear reaction temperature is 180°C to 380°C and the reaction time is 0.1min to 30min, to prepare bio-based compound modified liquid reclaimed rubber.

26. The tire inner liner rubber composition according to claim 25, wherein: The screw shearing reaction temperature is 200℃~350℃, and the reaction time is 1min-15min.

27. The mixing method of the tire inner liner rubber composition according to any one of claims 1 to 26, characterized in that: The following steps are involved: 1) First-stage mixing: Rubber, filler, modified cracked carbon black, stearic acid and other rubber processing aids except sulfur, vulcanization accelerator and zinc oxide are put into an internal mixer and mixed for 30-40 seconds at a speed of 35-45 rpm. The mixture is lifted and pressed every 20-30 seconds. When the temperature of the rubber compound reaches 125-135℃, the rubber is discharged and the pieces are peeled off. The rubber is then cooled at room temperature for 8-12 hours to obtain a first-stage masterbatch. 2) Final mixing: The masterbatch from step 1), sulfur, a vulcanization accelerator, and zinc oxide are placed in an internal mixer and mixed at a speed of 20-30 rpm. The mixture is lifted and pressed at intervals of 35 seconds, 20 seconds, and 25 seconds. When the temperature of the rubber material reaches 105°C, the rubber material is discharged and the sheet is removed. After cooling, the airtight layer rubber composition is obtained.

28. A tire, characterized in that: The airtight layer of the tire is prepared by vulcanizing the tire airtight layer rubber composition according to any one of claims 1 to 26.