Modified structure regulator and application

Abstract

The invention belongs to the technical field of high polymer materials, and particularly relates to a modified structure regulator and application. The structural formula of the modified structure regulator is as shown in formula (I), the modified structure regulator is applied to preparation of solution polymerized styrene-butadiene rubber to realize accurate regulation and control of a microstructure, and on the basis of the total mass of a structural unit from a conjugated diene monomer in a single molecular chain, the content of a vinyl structure is 25-40%, the content of trans-1, 4-butadienyl is 35-45%, and the content of cis-1, 4-butadienyl is 35-45%. And the content of 1, 4-butadienyl is 15-40%, so that the rolling resistance of the rubber is obviously reduced on the premise of not sacrificing or even improving the wet skid resistance and wear resistance.

Description

Technical Field

[0001] This invention belongs to the field of polymer materials technology, specifically relating to a modified structure modifier and its application. Background Technology

[0002] Traditional gasoline-powered vehicle tires prioritize wear resistance, while new energy vehicles, due to their greater weight and higher torque, require tires with higher demands for wet skid resistance, low rolling resistance, and fuel efficiency. With the rapid development of new energy vehicles, the demand for high-performance tires has increased significantly, and solution-polymerized styrene-butadiene rubber (SSBR) has become a key material for manufacturing green, high-performance tires due to the following advantages: (1) Solution polymerization process results in a narrow molecular weight distribution of the solution-polymerized styrene-butadiene rubber, which improves the uniformity of the rubber; (2) SSBR has better molecular chain flexibility and lower rolling resistance, which can reduce energy loss during tire driving and improve fuel efficiency. It also has excellent anti-slip and wear resistance. (3) Solution polymerization is cleaner than emulsion polymerization, reducing volatile organic compound emissions; it helps green tires, reduces vehicle energy consumption, and is environmentally friendly.

[0003] However, in the process of preparing solution-polymerized styrene-butadiene rubber by anionic polymerization, the reaction rate of styrene itself is much lower than that of butadiene, making it difficult to accurately control the type and quantity of structural units generated. As a result, the prepared solution-polymerized styrene-butadiene rubber cannot simultaneously achieve wet slip resistance, low rolling resistance and high wear resistance, and cannot meet the requirements for high performance. Summary of the Invention

[0004] Therefore, the technical problem to be solved by the present invention is that the microstructure control ability of the existing solution-polymerized styrene-butadiene rubber in the anionic polymerization process is poor, and the balance relationship of vinyl, cis-1,4-butadiene and trans-1,4-butadiene groups cannot be effectively and accurately controlled, thus failing to take into account the defects of anti-slip properties, rolling resistance and wear resistance. Therefore, the present invention provides a modified structure regulator and its application.

[0005] Therefore, the present invention provides the following technical solution: The first aspect of this invention protects a modified structure modifier, wherein the modified structure modifier has the structural formula shown in formula (I); (Formula I) Where n1 and n2 are integers, and n1 + n2 ≥ 1; R1 is selected from alkylene, arylene, and cycloalkylene groups; X is selected from S or O; a is an integer, and a is selected from 0 or 1; R2 is selected from alkyl, aryl, cycloalkyl, epoxyalkyl, ether, and thioether groups.

[0006] In one alternative implementation, n1+n2 is selected from 1, 2 or 3.

[0007] In one alternative embodiment, R1 is selected from straight-chain or branched C1-C4 alkylene groups, C6-C6 alkylene groups. 10 arylene and C3-C6 cycloalkylene compounds.

[0008] In one alternative implementation, R2 is selected from straight chains or branched chains C1-C. 10 Alkyl, C7-C 10 aryl, C3-C6 cycloalkyl, C2-C 10 Epoxyalkyl, C2-C 10 ether group, C2-C 10 The thioether group.

[0009] In one alternative embodiment, R1 is selected from straight-chain or branched C1-C4 alkylene groups, preferably selected from methylene, ethylene, or propylene.

[0010] In one alternative implementation, R2 is selected from straight chains or branched chains C1-C. 10 Alkyl, C2-C 10 Epoxyalkyl, C2-C 10 ether group, C2-C 10 The thioether group; preferably, R2 is selected from -OCH(CH3)OCH2CH3 or -OCH(CH3)SCH2CH3.

[0011] In this invention, 1H NMR spectroscopy is used to characterize the structure of the modified structure modifier.

[0012] In this invention, the preparation method of the modified structure regulator is a conventional method in organic synthesis. As long as the structure protected by the first aspect of this invention can be obtained, no excessive limitations are imposed.

[0013] The second aspect of this invention protects an anionic polymerization method, wherein the anionic polymerization method includes the following steps: in the presence of a structure modifier, an initiator, and a solvent, a monomer undergoes a polymerization reaction and a coupling reaction to obtain a polymer; The structure modifier includes the aforementioned modified structure modifier; The monomers include monovinyl aromatic hydrocarbons and conjugated dienes.

[0014] In one optional embodiment, the amount of the initiator added is 0.2-20 mmol / 100g monomer, optionally 0.25-3 mmol / 100g monomer.

[0015] In one alternative embodiment, the initiator comprises an organometallic initiator.

[0016] In this invention, the conditions for initiation are conventional conditions in the art, and typically, without limitation, the initiation temperature is 20-25°C.

[0017] In one optional embodiment, the molar ratio of the metal elements in the structure modifier and the organometallic initiator is (0.01-25):1.

[0018] In one alternative embodiment, the organometallic initiator includes an organolithium initiator and / or an organosodium initiator.

[0019] In one optional embodiment, the organolithium initiator includes at least one selected from methyllithium, ethyllithium, n-butyllithium, n-propyllithium, cyclopentyllithium, tolyllithium, butylphenyllithium, sec-butyllithium, and tert-butyllithium, and may be selected as n-butyllithium.

[0020] In one alternative embodiment, the solvent includes at least one selected from n-hexane, cyclohexane, cyclopentane, pentane, and toluene.

[0021] In one alternative embodiment, the mass ratio of the monomer to the solvent is 1:(4-9).

[0022] In one optional embodiment, the structure modifier further includes a polarity modifier, optionally including at least one of tetrahydrofuran, tetrahydrofurfuryl ether, diethylene glycol dimethyl ether, diethyl ether, 2-methyltetrahydrofuran, and anisole.

[0023] In one optional embodiment, when the structure modifier is a modified structure modifier and a polar modifier, the molar ratio of the modified structure modifier to the polar modifier is 1:(0.1-1).

[0024] In one alternative embodiment, the monovinyl aromatic hydrocarbon includes at least one of styrene, α-methylstyrene, m-methylstyrene, and p-methylstyrene.

[0025] In one optional embodiment, the amount of the monovinyl aromatic hydrocarbon added is 5-30 wt% of the monomer mass, optionally 10-30 wt%.

[0026] In one optional embodiment, the conjugated diene includes at least one selected from 1,3-butadiene, 2-methyl-1,3-butadiene, 1,3-hexadiene, 1,3-pentadiene, cyclopentadiene, and 3-octadiene, and may be 1,3-butadiene.

[0027] In one optional embodiment, the amount of the conjugated diene added is 70-95 wt% of the monomer mass, optionally 70-90 wt%.

[0028] In one optional embodiment, the polymerization reaction conditions include: a polymerization temperature of 0-130°C, optionally 50-80°C; a pressure of 0.1-0.8 MPa, optionally 0.2-0.4 MPa; and a time of 30 min-10 h, optionally 30 min-2 h.

[0029] In one optional embodiment, when the conversion rate of the monomer reaches 95% or more, a coupling agent and a capping agent are added to obtain a polymer.

[0030] In this invention, taking styrene and butadiene as examples, the monomer conversion rate is detected by gas chromatography. A sample is rapidly taken using a bottle containing a reaction terminator (such as methanol containing a polymerization inhibitor), and immediately shaken to terminate the reaction. An accurately weighed sample (0.1 g) is dissolved in a known mass of tetrahydrofuran; an accurate amount of internal standard (n-hexane) is added and mixed; the solution is injected into the gas chromatograph. By comparing the peak area of ​​the remaining monomer with the peak area of ​​the internal standard, and based on a working curve prepared using standard samples, the respective masses of the remaining styrene and butadiene in the sample are calculated. Furthermore, the conversion rate is calculated according to the formula: Conversion Rate = [1 - (m...] St剩余 +m Bd剩余 ) / (m St初始 +m Bd初始 The formula is calculated as ]×100%, where m St剩余 m represents the remaining mass of styrene. Bd剩余 m is the remaining mass of butadiene. St初始 m is the initial mass of styrene. Bd初始 The initial mass of butadiene was used to achieve a monomer conversion rate of over 95%.

[0031] In this invention, the coupling agent is a conventional coupling agent in the art, typically and non-limitingly including a star-shaped coupling agent, optionally N,N-dimethylaminopropyltrimethoxysilane; the molar ratio of the metal element in the coupling agent and the metal initiator is (0.01-2.5):1; optionally (0.05-2):1. The coupling reaction follows the polymerization reaction immediately, and the temperature of the coupling reaction is the same as the polymerization reaction temperature. After the coupling reaction begins, under nitrogen protection, samples are taken every 5 minutes, and the number-average molecular weight (Mn), weight-average molecular weight (Mw), and molecular weight distribution (PDI) of the samples are tested using gel permeation chromatography; when the difference in Mn between two consecutive samples is ≤5% and the difference in PDI is ≤0.05, a capping agent is added to terminate the reaction. Typically and non-limitingly, the coupling reaction time is 30-40 minutes.

[0032] In this invention, the capping agent is a conventional capping agent in the art. Typically, and not specifically, the capping agent includes at least one selected from water, methanol, ethanol, isopropanol, stearic acid, fatty acid, octadecyl alcohol, diphenyldiethoxysilane, 4-methoxydiphenyl ketone, 1,4-butanediol diglycidyl ether, diphenyldiethoxysilane, and chloropropyltrimethoxysilane; the fatty acid includes at least one selected from acetic acid, octanoic acid, decanoic acid, undecanoic acid, and isobutyric acid. The molar ratio of the metal element in the capping agent and the metal initiator is (0.5-2.5):1; optionally, it is (0.8-2):1.

[0033] A third aspect of this invention protects a solution-polymerized styrene-butadiene rubber, wherein the solution-polymerized styrene-butadiene rubber is prepared using the aforementioned modified structure modifier or prepared using the aforementioned anionic polymerization method.

[0034] In this invention, infrared spectroscopy is used to test solution-polymerized styrene-butadiene rubber. The total mass of structural units from conjugated diene monomers in a single molecular chain is used as the benchmark. The vinyl structure content is 25-40%, the trans-1,4-butadiene content is 35-45%, and the cis-1,4-butadiene content is 15-40%.

[0035] In this invention, taking 1,3-butadiene monomer as an example, the vinyl structure refers to... trans-1,4-butadienyl refers to cis-1,4-butadienyl refers to ,in," " is the connection point.

[0036] In this invention, the solution-polymerized styrene-butadiene rubber was tested using gel permeation chromatography. During the test, THF (tetrahydrofuran) was used as the mobile phase for characterization. The number average molecular weight of the solution-polymerized styrene-butadiene rubber was found to be 450,000-550,000, the molecular weight distribution was 1.2-2, and the coupling degree was 2.9-3.5.

[0037] The technical solution of this invention has the following advantages: 1. This invention provides a modified structure modifier having a structure as shown in Formula I, wherein specific values ​​of n1 and n2 ensure the introduction of a specific amount of crown ether ring structural units with steric hindrance and electronic effects into the molecule, providing a basis for coordination of the modified structure modifier; the specific structure of R1 can finely adjust the coordination stability and selectivity of the modified structure modifier through its own electronic effects and steric hindrance effects; X is S and / or O, introducing heteroatoms, utilizing the electronegativity and atomic radius of the heteroatoms to control the electron cloud density distribution, spatial configuration, and coordination ability with the modified structure modifier; a is specific... Certain values ​​can regulate the distance between functional groups and the core skeleton, as well as the flexibility of the molecule; the specific structure of R2 can fine-tune the hydrophobic / hydrophilic balance and steric hindrance of the molecule. When applied to the preparation of solution-polymerized styrene-butadiene rubber, it can achieve precise control of the microstructure. Based on the total mass of structural units from conjugated diene monomers in a single molecular chain, the vinyl structure content is 25-40%, the trans-1,4-butadiene content is 35-45%, and the cis-1,4-butadiene content is 15-40%. Without sacrificing or even improving the anti-slip and wear resistance, the rolling resistance of the rubber is significantly reduced.

[0038] 2. In this invention, when R2 is an epoxy alkyl group, ether group, or thioether group, in addition to adjusting the electron cloud density at the active chain end and affecting the monomer insertion rate, it can also serve as an additional Lewis basic site, generating a synergistic polar effect with the crown ether ring, and significantly enhancing the overall ability to regulate the polarity of the polymerization system.

[0039] 3. This invention provides an anionic polymerization method in which a specific modified structure regulator achieves precise control over the microstructure of solution-polymerized styrene-butadiene rubber. On the one hand, the modified structure regulator can complex the cations generated by the initiator, reducing the nucleophilicity of the active anion terminals and mitigating the differences in reactivity between different monomers, resulting in a random and uniform distribution of structural units in the polymerization product. On the other hand, the crown ether ring and its substituents in the modified structure regulator have high polarity, significantly promoting the conversion of butadiene monomers to high-energy 1,2-addition (vinyl) reactions. Based on the total mass of structural units from conjugated diene monomers in a single molecular chain, the vinyl structure content is 25-40%, the trans-1,4-butadiene content is 35-45%, and the cis-1,4-butadiene content is 15-40%. This significantly reduces the rolling resistance of the rubber without sacrificing or even improving its anti-slip and abrasion resistance. Furthermore, the preparation method is simple and easy to operate, requiring no complex feed control or high-cost modifiers, and the process has good stability, enabling industrial-scale production. Detailed Implementation

[0040] The following embodiments are provided to better understand the present invention and are not limited to the preferred embodiments described. They do not constitute a limitation on the content and scope of protection of the present invention. Any product that is the same as or similar to the present invention, derived by any person under the guidance of the present invention or by combining the features of the present invention with other prior art, falls within the protection scope of the present invention.

[0041] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains; the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the invention; the terms “comprising” and “having” and any variations thereof in the text of this invention are intended to cover non-exclusive inclusion.

[0042] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of the invention. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0043] The "range" disclosed in this invention is defined by a lower limit and an upper limit. A given range is defined by selecting a lower limit and an upper limit, which define the boundaries of the specific range. This range can include or exclude endpoints and can be arbitrarily combined; that is, any lower limit can be combined with any upper limit to form a range. In this invention, unless otherwise stated, the numerical range "ab" represents a shortened representation of any combination of real numbers from a to b, where a and b are real numbers. For example, the numerical range "0-5" indicates that all real numbers between "0-5" have been listed herein; "0-5" is merely a shortened representation of these numerical combinations. Furthermore, when a parameter is described as an integer ≥ 2, it is equivalent to disclosing that the parameter can be, for example, an integer 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, etc.

[0044] In the description of the embodiments of the present invention, the term "and / or" is merely a description of the relationship between related objects, indicating that there can be three relationships. For example, A and / or B can represent three situations: A exists alone, A and B exist simultaneously, and B exists alone.

[0045] In the description of the embodiments of the present invention, the term "at least one" refers to one or more (including two).

[0046] Where specific experimental steps or conditions are not specified in the examples, they can be performed according to the conventional experimental steps or conditions described in the literature in this field. Reagents or instruments whose manufacturers are not specified are all commercially available conventional reagent products.

[0047] Preparation Example 1 This preparation example provides a modified structure modifier, the preparation method of which includes the following steps: A 250 mL round-bottom flask was used as the reaction vessel. 10 mmol of 2-(allyloxymethyl)-18-crown-6-ether was dissolved in 50 mL of dichloromethane. 1.1 equivalents of mercuric acetate solid (based on 2-(allyloxymethyl)-18-crown-6-ether) was slowly added under stirring in an ice-water bath. The reaction was carried out at 25 °C in the dark for 3 h with stirring. Subsequently, an aqueous solution of sodium borohydride (1.1 g of NaBH4 dissolved in 20 mL of ice water) was added dropwise to the mixture under stirring in an ice-water bath at 0–5 °C. After the addition was complete, the ice bath was removed, the reaction mixture was allowed to rise to room temperature, and then stirred for 30 min. The filtrate was transferred to a separatory funnel, and the collected organic phase was neutralized and washed with saturated ammonium chloride and sodium chloride aqueous solutions, respectively. The organic phase was dried over anhydrous magnesium sulfate, filtered, and concentrated under reduced pressure to obtain the crude product. The crude product was then purified by column chromatography with silica gel as the stationary phase. A gradient elution of ethyl acetate and petroleum ether was used, ranging from 1:4 (ethyl acetate: petroleum ether) to 1:2 (ethyl acetate: petroleum ether), to obtain the modified structure regulator A1, with the following structural formula: NMR data: 1 H NMR (400 MHz, CDCl3)δ~1.15ppm(3H, -CH(CH3)); δ~1.25ppm(3H, -O-CH2-CH3); δ~3.40ppm(1H,>CH-O-); δ~3.55ppm(2H, -O-CH2-CH3); δ~3.65ppm(2H, -O-CH2-O-); δ~3.70ppm (23H, crown ether ring -CH2-).

[0048] Preparation Example 2 This preparation example provides a modified structure modifier, the preparation method of which includes the following steps: A 250 mL round-bottom flask was used as the reaction vessel. Nitrogen gas was first purged to remove oxygen. 10 mmol of 2-(allyloxymethyl)-18-crown-6-ether and 12 mmol of ethanethiol were dissolved in 150 mL of anhydrous dichloromethane. At room temperature, 0.15 equivalents of 2,2-dimethoxy-2-phenylacetophenone were added as a base of 2-(allyloxymethyl)-18-crown-6-ether. After the addition was complete, the reaction solution was irradiated under 365 nm UV light with stirring. Thin-layer chromatography was used to monitor the reaction, and the reaction was stopped after 12 h. The reaction solution was washed with saturated sodium sulfite aqueous solution, followed by three washes of the organic phase with deionized water. The solution was then dried with anhydrous magnesium sulfate and filtered. After the reaction was complete, the dichloromethane was removed by rotary evaporation under reduced pressure at 30 °C. The modified structure modifier A2 was obtained by column chromatography purification, with the following structural formula: NMR data: 1 H NMR (400 MHz, CDCl3) δ~1.05ppm (3H, -CH(CH3)); δ~1.25ppm (3H,-S-CH2-CH3); δ~2.50 ppm (2H, -S-CH2-CH3); δ~3.35ppm (1H,>CH-S-); δ~3.60 ppm (2H, -O-CH2-O-); δ~3.65ppm (23H, crown ether ring -CH2-).

[0049] Example 1 This embodiment provides an anionic polymerization method, including the following steps: The polymerization was carried out in a 2L stainless steel reactor. Under a nitrogen atmosphere, 7.5g of styrene, 42.5g of 1,3-butadiene, and 400g of n-hexane were added sequentially. Then, 0.035mmol of the structure modifier A1 was added. After the system was purified with 0.280mmol of n-butyllithium, 0.143mmol of n-butyllithium was added to initiate the polymerization. The initiation temperature was 20℃, the polymerization temperature was 65℃, and the pressure was 0.3MPa. After 70min of polymerization, the monomer conversion rate reached over 99%. 0.035mmol of dimethylaminopropyltrimethoxysilane was added to the reactor, and the coupling reaction was carried out for 30min. The difference in number-average molecular weight (Mn) between two consecutive samples was ≤5%, and the difference in PDI was ≤0.05. The reaction was terminated by adding 0.3mmol of 4-methoxydiphenyl ketone. After nitrogen stripping for 5h, the product was dried to obtain solution-polymerized styrene-butadiene rubber.

[0050] Example 2 This embodiment provides an anionic polymerization method, which is prepared in accordance with the method of Example 1, except that the modifying structure regulator A1 is replaced with an equal mass of A2.

[0051] Example 3 This embodiment provides an anionic polymerization method, which is prepared in accordance with the method of Example 1, except that the amount of modified structure regulator A1 is 0.020 mmol.

[0052] Example 4 This embodiment provides an anionic polymerization method, which is prepared in accordance with the method of Example 1, except that the amount of modified structure regulator A1 is 0.050 mmol.

[0053] Example 5 This embodiment provides an anionic polymerization method, the preparation method including the following steps: The method is the same as in Example 1, except that 0.035 mmol of modified structure modifier A1 is replaced with 0.0175 mmol of modified structure modifier A1 and 0.0175 mmol of tetrahydrofuran.

[0054] Example 6 This embodiment provides an anionic polymerization method. The preparation method is the same as in Example 1, except that the polymerization temperature is 50°C, the pressure is 0.1 MPa, and the polymerization reaction time is 1.5 h.

[0055] Example 7 This embodiment provides an anionic polymerization method, which is prepared in accordance with the method of Example 1, except that 10g of styrene and 40g of 1,3-butadiene are added.

[0056] Example 8 This embodiment provides an anionic polymerization method, which is prepared in accordance with the method of Example 1, except that 4g of styrene and 46g of 1,3-butadiene are added.

[0057] Comparative Example 1 This comparative example provides an anionic polymerization method, which is prepared in accordance with the method of Example 1, except that the modified structure modifier A1 is replaced with 18-crown-6.

[0058] Comparative Example 2 This comparative example provides an anionic polymerization method, which is prepared in accordance with the method of Example 1, except that the modifying structure modifier A1 is replaced with tetrahydrofuran.

[0059] Test case Molecular weight and molecular weight distribution were determined using gel permeation chromatography with THF as the mobile phase. Infrared spectroscopy was used to test solution-polymerized styrene-butadiene rubber, with the total mass of structural units from conjugated diene monomers in a single molecular chain as the benchmark, and the content of vinyl structure, trans-1,4-butadienyl, and cis-1,4-butadienyl groups. The specific test results are shown in Table 1; Table 1 Intrinsic Properties Test of Solution Polymerized Styrene-Butadiene Rubber

[0060] Note: PDI is the ratio of weight-average molecular weight (Mw) to number-average molecular weight (Mn), representing the dispersion of the polymer. The results in Table 1 show that the polarity of the modified group is positively correlated with the system's regulatory ability. Meanwhile, the cyclic structure of the crown ether provides more regulatory sites, achieving a better regulatory effect. By changing the modified group and the amount added to the structure regulator, based on the total mass of structural units from conjugated diene monomers in a single molecular chain, the vinyl structure content is 25-40%, the trans-1,4-butadienyl content is 35-45%, and the cis-1,4-butadienyl content is 15-40%.

[0061] 500g of solution-polymerized styrene-butadiene rubber, 8g of sulfur, 6g of antioxidant 4020, 12g of stearic acid, 6g of tetramethylthiuram disulfide, 400g of silica, and 150g of TDAE (environmentally friendly aromatic oil) prepared in the examples and comparative examples were added to a sinking internal mixer and mixed at 150°C for 5 minutes. After mixing, the material was discharged and placed in an open mill. The roller temperature was controlled at 50°C and the roller gap was 2mm. The process of forming a triangular bundle 4 times and rolling 6 times was carried out to obtain a tire tread rubber sample. Average wear degree (DIN) is measured using a DIN wear tester. First, the sample mass and density are weighed and recorded as m1 and ρ, respectively. The sample is then fixed on a rotating disk with a radius r of 8 cm, and a load F is applied. N The abrasion force was 2.5 N, causing the sandpaper to rotate and rub the sample surface at a speed of 19 rpm / min. The test time was 126 s. After the test, the mass m2 of the sample and the degree of wear A were measured. V =ΔV / (F N ×s)×10 6 Where ΔV = (m1-m2) / ρ, relative gliding distance s = 2πr×n×t, where r, n, and t represent the turntable radius, rotation speed (rpm), and time, respectively. The average wear level is obtained by taking the average value of 3 tests. The wet skid resistance was characterized by the consumption factor Tanδ (0℃), and the rolling resistance was characterized by the consumption factor Tanδ (60℃). The tread rubber sample was fixed on the thermal analyzer tester, the frequency was controlled at 10Hz, the heating rate was 3K / min, and the test temperature was -80℃ to 80℃. The specific test results are shown in Table 2; Table 2 Performance Tests of Tread Rubber Samples

[0062] As can be seen from the data in Table 2, the present invention can significantly reduce the rolling resistance of rubber without sacrificing or even improving its anti-slip and wear resistance.

[0063] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.

Claims

1. A modified structure modifier, characterized in that, The structural formula of the modified structure regulator is shown in formula (I); (Equation I) Where n1 and n2 are integers, and n1 + n2 ≥ 1; R1 is selected from alkylene, arylene, and cycloalkylene groups; X is selected from S or O; a is an integer, and a is selected from 0 or 1; R2 is selected from alkyl, aryl, cycloalkyl, epoxyalkyl, ether, and thioether groups.

2. The modified structure modifier according to claim 1, characterized in that, n1+n2 is selected from 1, 2 or 3; And / or, R1 is selected from straight-chain or branched C1-C4 alkylene groups, C6-C 10 arylene, C3-C6 cycloalkylene; And / or, R2 is selected from straight or branched chains C1-C 10 Alkyl, C7-C 10 aryl, C3-C6 cycloalkyl, C2-C 10 Epoxyalkyl, C2-C 10 ether group, C2-C 10 The thioether group.

3. The modified structure modifier according to claim 2, characterized in that, R1 is selected from straight-chain or branched C1-C4 alkylene groups, preferably methylene, ethylene, or propylene. And / or, R2 is selected from straight or branched chains C1-C 10 Alkyl, C2-C 10 Epoxyalkyl, C2-C 10 ether group, C2-C 10 The thioether group; preferably, R2 is selected from -OCH(CH3)OCH2CH3 or -OCH(CH3)SCH2CH3.

4. An anionic polymerization method, characterized in that, The anionic polymerization method includes the following steps: in the presence of a structure modifier, an initiator, and a solvent, the monomer undergoes a polymerization reaction and a coupling reaction to obtain a polymer; The structure modifier includes the modified structure modifier according to any one of claims 1-3; The monomers include monovinyl aromatic hydrocarbons and conjugated dienes.

5. The anionic polymerization method according to claim 4, characterized in that, The amount of the initiator added is 0.2-20 mmol / 100g monomer, and can be selected as 0.25-3 mmol / 100g monomer; And / or, the initiator includes an organometallic initiator; Optionally, the molar ratio of the metal elements in the structure modifier and the organometallic initiator is (0.01-25):1; Optionally, the organometallic initiator includes an organolithium initiator and / or an organosodium initiator; Optionally, the organolithium initiator includes at least one of methyllithium, ethyllithium, n-butyllithium, n-propyllithium, cyclopentyllithium, tolyllithium, butylphenyllithium, sec-butyllithium, and tert-butyllithium, and may be n-butyllithium; And / or, the solvent includes at least one of n-hexane, cyclohexane, cyclopentane, pentane, and toluene; And / or, the mass ratio of the monomer to the solvent is 1:(4-9).

6. The anionic polymerization method according to claim 4 or 5, characterized in that, The structure modifier also includes a polarity modifier, optionally including at least one of tetrahydrofuran, tetrahydrofurfuryl ether, diethylene glycol dimethyl ether, diethyl ether, 2-methyltetrahydrofuran, and anisole; Optionally, when the structure modifier is a modified structure modifier and a polar modifier, the molar ratio of the modified structure modifier and the polar modifier is 1:(0.1-1).

7. The anionic polymerization method according to any one of claims 4-6, characterized in that, The monovinyl aromatic hydrocarbon includes at least one of styrene, α-methylstyrene, m-methylstyrene, and p-methylstyrene; And / or, the amount of the monovinyl aromatic hydrocarbon added is 5-30 wt% of the monomer mass, optionally 10-30 wt%; And / or, the conjugated diene includes at least one selected from 1,3-butadiene, 2-methyl-1,3-butadiene, 1,3-hexadiene, 1,3-pentadiene, cyclopentadiene, and 3-octadiene, optionally 1,3-butadiene; And / or, the amount of the conjugated diene added is 70-95 wt% of the monomer mass, optionally 70-90 wt%.

8. The anionic polymerization method according to any one of claims 4-7, characterized in that, The conditions for the polymerization reaction include: polymerization temperature of 0-130℃, optionally 50-80℃; pressure of 0.1-0.8MPa, optionally 0.2-0.4MPa; and time of 30min-10h, optionally 30min-2h.

9. The anionic polymerization method according to any one of claims 5-8, characterized in that, When the conversion rate of the monomer reaches 95% or more, a coupling agent and a capping agent are added to obtain the polymer. Optionally, the molar ratio of the metal elements in the coupling agent and the metal initiator is (0.01-2.5):1; alternatively, it is (0.05-2):

1. Optionally, the molar ratio of the metal elements in the capping agent and the metal initiator is (0.5-2.5):1; or optionally (0.8-2):

1.

10. A solution-polymerized styrene-butadiene rubber, characterized in that, Solution-polymerized styrene-butadiene rubber (SBR) prepared using the modified structure modifier described in any one of claims 1-3, or solution-polymerized SBR prepared using the anionic polymerization method described in any one of claims 4-9.

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