Modified hydrogenated petroleum resin for rubber tire and method for preparing the same

Abstract

The application belongs to the technical field of petroleum resin, and particularly relates to a modified hydrogenated petroleum resin for rubber tires and a preparation method thereof. The application realizes the balance between wet skid resistance and rolling resistance by adjusting the structure and process. In the aspect of structure, the hydrogenation rate is controlled by bromine value, N-substituted maleimide is introduced as a molecular bridge, the Payne effect caused by filler aggregation is reduced, the rolling resistance is reduced, the bonding force between the resin and the filler interface is enhanced, and the mechanical properties are effectively improved. In the aspect of process, the combination process of melt grafting and two-stage stepwise devolatilization is adopted, and strong shearing and high vacuum environment are used, which not only ensures the high efficiency and uniformity of the grafting reaction, but also deeply removes small molecule volatile components, avoids the migration and precipitation of small molecule substances, reduces the internal friction heat from the source, and further optimizes the rolling resistance.

Description

Technical Field

[0001] This invention belongs to the field of petroleum resin technology, specifically relating to a modified hydrogenated petroleum resin for rubber tires and its preparation method. Background Technology

[0002] Rubber tires often need to achieve the best balance between wet skid resistance, rolling resistance, and wear resistance. Reducing rolling resistance helps reduce fuel consumption, while improving wet skid resistance is directly related to vehicle braking safety. Petroleum resin, as a rubber additive, has functions such as plasticizing, reinforcing, and improving processing performance.

[0003] However, existing petroleum resins still face the challenge of simultaneously achieving both wet skid resistance and low rolling resistance in practical applications. Traditional petroleum resins often fail to provide sufficient loss factors near 0°C, resulting in poor wet skid resistance. Secondly, the Payne effect caused by the filler interface limits the release of performance. Silica is rich in silanols on its surface, which are highly polar, while non-polar petroleum resins have weak interfacial bonding. This incompatibility leads to phase separation or abnormal aggregation of resin molecules around the filler network, triggering the Payne effect. This directly increases the hysteresis loss of the compound, not only offsetting the low rolling resistance advantage brought by silica but also deteriorating the wet skid resistance, thus significantly reducing the reinforcing and tackifying effects of the resin.

[0004] Therefore, it is of practical significance to develop a new type of modified hydrogenated petroleum resin that can break the performance constraint between wet skid resistance and rolling resistance and effectively suppress the Payne effect of filler. Summary of the Invention

[0005] To address the aforementioned problems in the prior art, this invention provides a modified hydrogenated petroleum resin for rubber tires and its preparation method.

[0006] The objective of this invention can be achieved through the following technical solutions: A method for preparing modified hydrogenated petroleum resin for rubber tires includes the following steps: adding hydrogenated petroleum resin, N-substituted maleimide, and initiator into a twin-screw extruder for melt grafting reaction, and then performing two-stage devolatilization in the devolatilization section and the strip-type devolatilizer of the twin-screw extruder to obtain modified hydrogenated petroleum resin.

[0007] The hydrogenated petroleum resin is a petroleum resin that has undergone hydrogenation treatment, with a hydrogenation rate of 30-50%. The N-substituted maleimide has an alkoxy group and can be grafted onto the hydrogenated petroleum resin through its carbon-carbon double bond.

[0008] Preferably, the petroleum resin has a bromine value of 30-50 g Br2 / 100 g and a molecular weight of 800-1500.

[0009] Preferably, the reaction section conditions of the twin-screw extruder include: temperatures of 170~180℃, 180~190℃, 190~200℃, and 200~210℃, with a total residence time of 5~10 min.

[0010] Preferably, the conditions for the devolatilization section of the twin-screw extruder include: a temperature of 205~215℃, an absolute pressure of 2~3kPa, and a residence time of 2~3min.

[0011] Preferably, the conditions of the strip-type devolatilizer include: internal temperature of 235~245℃, absolute pressure of 1~1.5kPa, and strip falling time of 10~20s.

[0012] Preferably, based on 100 parts of hydrogenated petroleum resin: 0.5 to 3 parts of N-substituted maleimide and 0.1 to 0.2 parts of initiator.

[0013] Preferably, the initiator includes at least one of dicumyl peroxide, di-tert-butyl peroxide, and dibenzoyl peroxide.

[0014] This invention combines dynamic devolatilization equipment (devolatilization section of a twin-screw extruder) with static devolatilization equipment (drop-out type devolatilizer). The twin-screw extruder combines melting reaction and devolatilization through shearing and stirring, but long-term shearing may lead to yellowing. By staged devolatilization, the pressure of the twin-screw extruder is reduced, while the drop-out type devolatilizer plays the role of deep devolatilization and stable output, ensuring stable output quality and improving the freedom of industrial operation.

[0015] Preferably, the preparation method of the hydrogenated petroleum resin includes: adding a catalyst and petroleum resin to a high-pressure reactor, sealing the reactor, purging with nitrogen, heating to 200-220°C with stirring, then purging the nitrogen with hydrogen, controlling the reaction pressure at 2-3 MPa, continuously adding hydrogen, measuring the bromine value, calculating that the hydrogenation rate reaches 30-50%, ending the reaction, removing the catalyst, and obtaining the hydrogenated petroleum resin by distillation.

[0016] Preferably, the petroleum resin includes at least one of C5 petroleum resin and C9 petroleum resin.

[0017] Preferably, the catalyst comprises Ni / γ Al2O3, Ni / C, Pt / γ At least one of Al2O3, Pt / C, and Pd / C, with a catalyst addition amount of 1~2wt% petroleum resin.

[0018] Preferably, the preparation method of the N-substituted maleimide includes the following steps: under a nitrogen atmosphere, isocyanate silane and solvent are added to a flask, followed by the addition of maleic anhydride, the temperature is raised to 80~100℃, and the reaction is maintained at this temperature for 6~10h. After the reaction is completed, the N-substituted maleimide is obtained by filtration and drying.

[0019] The -NCO group of the isocyanate silane first forms an unstable seven-membered ring with the anhydride group of maleic anhydride. As the reaction continues to be heated, this seven-membered ring intermediate decomposes to form an imide five-membered ring and releases carbon dioxide gas.

[0020] Preferably, the mass ratio of the isocyanate silane to maleic anhydride is 1:0.3~0.5.

[0021] Preferably, the isocyanate silane includes at least one of 3-isocyanate propyltrimethoxysilane, 3-isocyanate propyltriethoxysilane, and 3-isocyanate propylmethyldimethoxysilane.

[0022] Preferably, the solvent includes at least one of N,N-dimethylformamide, N,N-dimethylacetamide, and N-methylpyrrolidone.

[0023] Preferably, the mass of the solvent is the mass of the isocyanate silane.

[0024] A modified hydrogenated petroleum resin for rubber tires obtained by the above-mentioned method for preparing modified hydrogenated petroleum resin for rubber tires.

[0025] The beneficial effects of this invention are as follows: This invention obtains modified hydrogenated petroleum resin through melt grafting and devolatilization, and adjusts its structure and process to achieve a balance between wet skid resistance and rolling resistance, reducing the Payne effect caused by fillers, and enabling its application in rubber tires. Specifically: In terms of structure, this invention uses a petroleum resin hydrogenation rate controlled by bromine value. This effectively prevents the resin from gelling due to excessive cross-linking of unsaturated bonds during melt grafting, while retaining an appropriate amount of non-polar skeleton and reactive sites. This ensures good compatibility between the resin and the rubber matrix to support anti-slip performance and provides grafting anchors for subsequent functionalization modification. By introducing N-substituted maleimide as a molecular bridge, the steric hindrance effect of maleic anhydride groups and the chemical bonds formed by silane groups and silanol groups on the surface of silica are used to jointly disrupt the hydrogen bond network between silica fillers. This significantly reduces the Payne effect caused by filler aggregation, reduces rolling resistance, and enhances the bonding force between the resin and filler interfaces, effectively improving mechanical properties.

[0026] In terms of process, this invention adopts a combination of melt grafting and two-stage stepwise devolatilization, combined with dynamic devolatilization and static devolatilization, and with strong shear and high vacuum environment. This not only ensures the high efficiency and uniformity of the grafting reaction, but also deeply removes small molecule volatiles such as unreacted monomers, initiator fragments and oligomers. This avoids the migration and precipitation of small molecules during the dynamic service of rubber, reduces internal heat generation from the source, and further optimizes rolling resistance.

[0027] In summary, this invention solves the technical contradiction of traditional petroleum resins being unable to simultaneously achieve wet skid resistance and low rolling resistance through integrated control of structure, process, and performance. At the same time, it improves filler dispersibility and interfacial bonding strength, providing technical support for the development of high-performance rubber tires. Attached Figure Description

[0028] Figure 1 The graph shows the relationship between shear modulus and strain when the resin samples of Example 1, Comparative Examples 1-6 and Comparative Example 9 of this invention are applied to rubber. Detailed Implementation

[0029] To further illustrate the technical means and effects of the present invention in achieving its intended purpose, the following detailed description of the specific implementation methods, structures, features, and effects of the present invention, in conjunction with the accompanying drawings and preferred embodiments, is provided.

[0030] Example 1 Step 1: Under a nitrogen atmosphere, 10g of 3-isocyanate propyltrimethoxysilane and 10g of N-methylpyrrolidone were added to a flask, followed by 3g of maleic anhydride. The temperature was raised to 80℃ and the reaction was maintained for 10h. After the reaction was completed, the N-substituted maleimide was obtained by filtration and drying. FT-IR (KBr, cm -1 ):2925,2856(νC-H),1772,1708(νC=O),1635(νC=C),1450(δC-H),1185(νC-O),1095(νSi-OC),915(δ-CO-NH-CO-),780(νSi-C); ¹H NMR (CDCl3, δ / ppm): 0.56 (t, 2H), 1.51 (m, 2H), 3.55 (s, 9H), 4.00 (t, 2H), 7.86 (s, 2H).

[0031] Based on the above characterization results: FT-IR at 1772 cm⁻¹ -1 and 1708cm -1 The absorption peak at 1635 cm⁻¹ is attributed to the asymmetric and symmetric stretching vibrations of the carbonyl group (C=O) on the five-membered ring of maleimide. -1 The absorption peak corresponds to the stretching vibration of the carbon-carbon double bond (C=C) within the imide ring, at 1095 cm⁻¹. -1 The absorption peak at 2260 cm⁻¹ is attributed to the asymmetric stretching vibration of Si-OC in the trimethoxy group. -1 No characteristic peaks of isocyanate groups (-NCO) were observed nearby. 1 The absence of methylene proton signals linked to isocyanate groups in the 1H NMR spectrum indicates that the modified maleimide was successfully synthesized.

[0032] Step 2: Add 1g Pd / C and 100g C5 petroleum resin (bromine value 30g Br2 / 100g, molecular weight 800) to the autoclave, seal the autoclave, purge with nitrogen, heat to 220℃ with stirring, then purge the nitrogen with hydrogen, control the reaction pressure at 2MPa, continue adding hydrogen, measure the bromine value, calculate that the hydrogenation rate reaches 50%, stop the reaction, remove the catalyst, and obtain hydrogenated petroleum resin by distillation; FT-IR (KBr, cm) before hydrogenation -1 ):2950,2925,2856(νC-H,s),1605,1651(νC=C,m),1450,1374(δC-H,m),970(γ-CH=CH-,m),895(γ=CH2,w),682(γC-H,w); FT-IR (KBr, cm) after hydrogenation -1 ):2950,2925,2856(νC-H,s),1651(νC=C,w),1450,1374(δC-H,m),970(γ-CH=CH-,w),895(γ=CH2,w),682(γC-H,w).

[0033] Based on the above characterization results: compared with before hydrogenation, it is located at 1605 cm⁻¹ -1 and 1651cm -1 The intensity of the C=C stretching vibration absorption peak at 970 cm⁻¹ is weakened, and the absorption peak intensity at 970 cm⁻¹ is also reduced. -1 The decrease in the characteristic peak of the out-of-plane bending vibration of the trans-CH=CH- group indicates that some olefin double bonds in the resin have been effectively saturated, while the peak at 895 cm⁻¹... -1 The peak of the terminal olefin (=CH2) rocking vibration and 682 cm⁻¹ -1 The presence of out-of-plane bending peaks at CH indicates that some double bonds are still retained in the resin, which, combined with other findings, demonstrates the successful preparation of hydrogenated petroleum resin.

[0034] Step 3: Set the reaction section temperature of the twin-screw extruder to 170℃, 180℃, 190℃, and 200℃ sequentially, with a total residence time of 10 min. Set the devolatilization section temperature to 205℃ and the absolute pressure to 3 kPa. Set the temperature inside the strip-type devolatilizer to 235℃ and the absolute pressure to 1.5 kPa. Set the strip falling time to 20 s and the residence time to 3 min. Add 50 g of hydrogenated petroleum resin, 0.25 g of N-substituted maleimide, and 0.05 g of benzoyl peroxide to the twin-screw extruder for melt grafting reaction. Then, the mixture enters the devolatilization section and the strip-type devolatilizer of the twin-screw extruder to obtain modified hydrogenated petroleum resin.

[0035] FT-IR (KBr, cm -1):2950,2925,2856(νC-H),1772,1708(νC=O),1450,1374(δC-H),1185(νC-O),1095(νSi-OC),915(δ-CO-NH-CO-),780(νSi-C); ¹H NMR (CDCl3, δ / ppm): 0.56 (m, 2H), 1.51 (m, 2H), 2.60 (t, 2H), 3.55 (s, 9H), 5.40 (br).

[0036] Based on the above characterization results: at 1772cm -1 and 1708cm -1 Absorption peaks for both asymmetric and symmetric stretching vibrations of the maleimide cyclic carbonyl group (C=O) appeared at 1095 cm⁻¹. -1 780cm -1 Characteristic absorptions of Si-OC and Si-C appear at the locations, respectively, while at... 1 The δ 3.55 ppm methoxy single peak observed in the 1H NMR spectrum is attributed to -Si(OCH3)3, indicating that the modified maleimide C=C has been grafted onto the hydrogenated C5 petroleum resin through the residual double bond of the resin skeleton.

[0037] Example 2 Step 1: Under a nitrogen atmosphere, 10g of 3-isocyanate propyltrimethoxysilane and 10g of N-methylpyrrolidone were added to a flask, followed by 4g of maleic anhydride. The temperature was raised to 90℃ and the reaction was maintained for 8 hours. After the reaction was completed, the N-substituted maleimide was obtained by filtration and drying. Step 2: Add 1.5g Pd / C and 100g C5 petroleum resin (bromine value 40g Br2 / 100g, molecular weight 1000) to the autoclave, seal the autoclave, purge with nitrogen, heat to 210℃ with stirring, then purge the nitrogen with hydrogen, control the reaction pressure at 2.5MPa, continue adding hydrogen, measure the bromine value, calculate that the hydrogenation rate reaches 40%, stop the reaction, remove the catalyst, and obtain hydrogenated petroleum resin by distillation; Step 3: Set the reaction section temperature of the twin-screw extruder to 175℃, 185℃, 195℃, and 205℃ sequentially, with a total residence time of 8 minutes. Set the devolatilization section temperature to 210℃ and the absolute pressure to 2.5 kPa. Set the temperature inside the strip-type devolatilizer to 240℃ and the absolute pressure to 1.2 kPa. Set the strip falling time to 15 seconds and the residence time to 2.5 minutes. Add 50 g of hydrogenated petroleum resin, 0.5 g of N-substituted maleimide, and 0.05 g of benzoyl peroxide to the twin-screw extruder for melt grafting reaction. Then, feed the mixture into the devolatilization section and strip-type devolatilizer of the twin-screw extruder to obtain modified hydrogenated petroleum resin.

[0038] Example 3 Step 1: Under a nitrogen atmosphere, 10g of 3-isocyanate propyltrimethoxysilane and 10g of N-methylpyrrolidone were added to a flask, followed by 5g of maleic anhydride. The temperature was raised to 100℃ and the reaction was maintained for 6 hours. After the reaction was completed, the N-substituted maleimide was obtained by filtration and drying. Step 2: Add 2g Pd / C and 100g C5 petroleum resin (bromine value 50g Br2 / 100g, molecular weight 1500) to the autoclave, seal the autoclave, purge with nitrogen, heat to 200℃ with stirring, then purge the nitrogen with hydrogen, control the reaction pressure at 3MPa, continue adding hydrogen, measure the bromine value, calculate that the hydrogenation rate reaches 30%, stop the reaction, remove the catalyst, and obtain hydrogenated petroleum resin by distillation; Step 3: Set the reaction section temperature of the twin-screw extruder to 180℃, 190℃, 200℃, and 210℃ sequentially, with a total residence time of 5 minutes. Set the devolatilization section temperature of the twin-screw extruder to 215℃ and the absolute pressure to 2 kPa. Set the temperature inside the strip-type devolatilizer to 245℃ and the absolute pressure to 1 kPa. Set the strip falling time to 10 seconds and the residence time to 2 minutes. Add 50 g of hydrogenated petroleum resin, 1.5 g of N-substituted maleimide, and 0.1 g of benzoyl peroxide to the twin-screw extruder for melt grafting reaction. Then, the mixture enters the devolatilization section and strip-type devolatilizer of the twin-screw extruder to obtain modified hydrogenated petroleum resin.

[0039] Example 4 Step 1: Under a nitrogen atmosphere, 10g of 3-isocyanate propyltriethoxysilane and 10g of N,N-dimethylformamide were added to a flask, followed by the addition of 3g of maleic anhydride. The temperature was raised to 80℃ and the reaction was maintained for 10h. After the reaction was completed, the N-substituted maleimide was obtained by filtration and drying. Step 2: Add 1g Pt / C and 100g C9 petroleum resin (bromine value 30g Br2 / 100g, molecular weight 1500) to the autoclave, seal the autoclave, purge with nitrogen, heat to 220℃ with stirring, then purge the nitrogen with hydrogen, control the reaction pressure at 2MPa, continue adding hydrogen, measure the bromine value, calculate that the hydrogenation rate reaches 50%, stop the reaction, remove the catalyst, and obtain hydrogenated petroleum resin by distillation; Step 3: Set the reaction section temperature of the twin-screw extruder to 170℃, 180℃, 190℃, and 200℃ sequentially, with a total residence time of 10 min. Set the devolatilization section temperature to 205℃ and the absolute pressure to 3 kPa. Set the temperature inside the strip-type devolatilizer to 235℃ and the absolute pressure to 1.5 kPa. Set the strip falling time to 20 s and the residence time to 3 min. Add 50 g of hydrogenated petroleum resin, 0.25 g of N-substituted maleimide, and 0.05 g of dicumyl peroxide to the twin-screw extruder for melt grafting reaction. Then, the mixture enters the devolatilization section and strip-type devolatilizer of the twin-screw extruder to obtain modified hydrogenated petroleum resin.

[0040] Example 5 Step 1: Under a nitrogen atmosphere, 10g of 3-isocyanate propylmethyldimethoxysilane and 10g of N,N-dimethylacetamide were added to a flask, followed by the addition of 3g of maleic anhydride. The temperature was raised to 80℃ and the reaction was maintained for 10h. After the reaction was completed, the N-substituted maleimide was obtained by filtration and drying. Step 2: Add 1g Ni / γ-Al2O3 and 100g C9 petroleum resin (bromine value 30g Br2 / 100g, molecular weight 1500) to the autoclave, seal the autoclave, purge with nitrogen, heat to 220℃ with stirring, then purge the nitrogen with hydrogen, control the reaction pressure at 2MPa, continue adding hydrogen, measure the bromine value, calculate that the hydrogenation rate reaches 50%, stop the reaction, remove the catalyst, and obtain hydrogenated petroleum resin by distillation; Step 3: Set the reaction section temperature of the twin-screw extruder to 170℃, 180℃, 190℃, and 200℃ sequentially, with a total residence time of 10 min. Set the devolatilization section temperature of the twin-screw extruder to 205℃ and the absolute pressure to 3 kPa. Set the temperature inside the strip-type devolatilizer to 235℃ and the absolute pressure to 1.5 kPa. Set the strip falling time to 20 s and the residence time to 3 min. Add 50 g of hydrogenated petroleum resin, 0.25 g of N-substituted maleimide, and 0.05 g of di-tert-butyl peroxide to the twin-screw extruder for melt grafting reaction. Then, the mixture enters the devolatilization section and strip-type devolatilizer of the twin-screw extruder to obtain modified hydrogenated petroleum resin.

[0041] Example 6 The difference between this embodiment and Embodiment 1 is that the reaction ends when the hydrogenation rate reaches 30% in step 2, while the remaining steps are roughly the same as in Embodiment 1.

[0042] Example 7 The difference between this embodiment and Embodiment 1 is that the reaction ends when the hydrogenation rate reaches 40% in step 2, while the remaining steps are roughly the same as in Embodiment 1.

[0043] Comparative Example 1 The difference between this comparative example and Example 1 is that C5 petroleum resin is used in step 3 instead of the hydrogenated petroleum resin obtained in Example 1, while the remaining steps are roughly the same as in Example 1.

[0044] Comparative Example 2 The difference between this comparative example and Example 1 is that step 3 involves physical blending 50g of hydrogenated petroleum resin and 0.25g of N-substituted maleimide to obtain a resin sample. The remaining steps are roughly the same as in Example 1.

[0045] Comparative Example 3 The difference between this comparative example and Example 1 is that maleic anhydride was used in step 3 instead of the N-substituted maleimide obtained in Example 1, while the remaining steps are largely the same as in Example 1.

[0046] Comparative Example 4 The difference between this comparative example and Example 1 is that step 3 does not include a twin-screw extruder devolatilization section, while the remaining steps are largely the same as in Example 1.

[0047] Comparative Example 5 The difference between this comparative example and Example 1 is that step 3 does not pass through the strip-type devolatilizer and the material is discharged directly, while the remaining steps are roughly the same as in Example 1.

[0048] Comparative Example 6 The difference between this comparative example and Example 1 is that in step 3, 3-isocyanate propyltrimethoxysilane is used instead of the N-substituted maleimide obtained in Example 1, while the remaining steps are largely the same as in Example 1.

[0049] Comparative Example 7 The difference between this comparative example and Example 1 is that the reaction ends when the hydrogenation rate reaches 20% in step 2, while the remaining steps are roughly the same as in Example 1.

[0050] Comparative Example 8 The difference between this comparative example and Example 1 is that the reaction ends when the hydrogenation rate reaches 60% in step 2, while the remaining steps are roughly the same as in Example 1.

[0051] The following tests were performed on the resin samples of Examples 1-7 and Comparative Examples 1-8: Softening point (°C): The resin samples were tested according to GB / T 4507-2014 Determination of softening point of asphalt using the ring and ball method.

[0052] Acid value (mg·g) -1 ): The resin samples were tested in accordance with GB / T 2895-2008 Plastics, Polyester Resins, Determination of Partial Acid Value and Total Acid Value.

[0053] Grafting rate (%): Calculated based on the increase in nitrogen element after grafting the resin sample.

[0054] Colorimetry: The resin sample was measured using the Gardner colorimeter in accordance with GB / T 22295-2008 Method for Determination of Color of Transparent Liquids (Gardner Colorimetry).

[0055] Hydrogenation rate (%): The bromine value is measured using an automatic bromine value analyzer, and the hydrogenation rate is calculated as follows: Hydrogenation rate = (bromine value before hydrogenation - bromine value after hydrogenation) / bromine value before hydrogenation.

[0056] Volatile content (%): The resin samples were tested in accordance with GB / T 24138-2022 "Petroleum Resins".

[0057]

[0058] As shown in Table 1, the softening point of Comparative Example 1 is higher than that of Example 1. This is because C5 petroleum resin was used instead of C5 hydrogenated petroleum resin, which easily leads to cross-linking between resins during melt grafting, thus increasing the softening point. Comparative Example 7, with a hydrogenation rate of 20%, also confirms this. Combined with Examples 6 and 7, it can be seen that when the hydrogenation rate is <30%, unsaturated bonds are easily over-cross-linked, consuming grafting sites and increasing steric hindrance, resulting in a decrease in the grafting rate. When the hydrogenation rate is >50%, the grafting rate is low, possibly because after over-hydrogenation, only grafting sites with greater steric hindrance are retained, resulting in insufficient grafting sites, which also leads to a decrease in the grafting rate. Comparative Example 3 uses maleic anhydride instead of N-substituted maleimide, and the acid value increases significantly. The difference in physical property testing shows that Example 1 effectively modifies maleic anhydride. Comparative Examples 4 and 5 have small molecule residues due to insufficient devolatilization, and their softening points are slightly lower than those of Example 1.

[0059] The resin samples obtained in Examples 1-7 and Comparative Examples 1-8 were subjected to the following tests for application in rubber: Rubber vulcanization sample formulation: 100 parts styrene-butadiene rubber (SSBR), 70 parts silica, 7 parts resin, 3.5 parts antioxidant 4020, and 2 parts sulfur (the resin samples obtained by replacing the resin samples corresponding to Examples 1-7 and Comparative Examples 1-8 in sequence are recorded as Examples 1-SSBR-7-SSBR and Comparative Examples 1-SSBR-8-SSBR, and Comparative Example 9-SSBR is set as a blank group without adding resin).

[0060] Rubber vulcanization sample preparation: The speed of the internal mixer was set to 70 r / min and the initial temperature was 80℃. The material was added and mixed at the beginning of the mixing. When the temperature reached 145℃, the speed was adjusted to 60 r / min and the mixing was continued for 3 minutes before the rubber was discharged. The sample was vulcanized on a flat vulcanizing instrument at 160℃ for 5 minutes to obtain the vulcanized sample. After being placed at room temperature for 24 hours, the performance was tested.

[0061] Tensile strength and elongation at break: The tensile stress-strain properties of vulcanized rubber or thermoplastic rubber were determined according to GB / T 528-2009. A universal electronic tensile testing machine was used at a speed of 500 mm / min, and dumbbell-shaped specimens were used.

[0062] Tear strength: The tear strength of vulcanized samples was determined according to GB / T 529-2008 for vulcanized rubber or thermoplastic rubber at a rate of 500 mm / min.

[0063] Volumetric wear: According to GB / T 9867-2008 Determination of abrasion resistance of vulcanized rubber or thermoplastic rubber, the density of the vulcanized sample is measured with a densitometer, and then the mass difference of the vulcanized rubber before and after wear is measured to calculate the wear volume.

[0064] Dynamic mechanical properties: The temperature of the sulfurized sample was scanned in tensile mode using a dynamic mechanical property spectrum analyzer, with a temperature range of -60℃ to 100℃, a heating rate of 3℃ / min, and a frequency of 10Hz.

[0065] BPST wet slip resistance test: According to ASTM E303-93, the vulcanized sample is tested using a pendulum friction coefficient tester. The cylindrical test block is fixed to the lower end of the pendulum friction coefficient tester arm, and the vulcanized sample is adhered to the cylindrical test block. The test plate surface is tilted at 20° and is a ceramic plate. The BPST value is calculated by measuring the friction coefficient: BPST value = 330μ / (3+μ), where μ corresponds to the friction coefficient.

[0066] Strain scanning analysis: The vulcanized samples were subjected to strain scanning tests using a rubber processing analyzer. Specific test conditions: test temperature 100℃, test frequency 60cpm, strain range: 0~400%. Shear modulus change ΔG' = G'(1% strain) - G'(100% strain).

[0067] Figure 1 The graph shows the relationship between shear modulus and strain when the resin samples of Example 1, Comparative Examples 1-6 and Comparative Example 9 of this invention are applied to rubber.

[0068]

[0069]

[0070] The shear modulus of rubber decreases with increasing strain; this phenomenon is called the Payne effect. The Payne effect is closely related to filler-filler and rubber-filler interactions. A greater decrease in shear modulus and a larger ΔG' value indicate a stronger filler-filler network and poorer filler dispersion in the system. Figure 1As shown in Table 3, Example 1 has a lower ΔG' value, indicating that the modified hydrogenated petroleum resin prepared in this invention significantly reduces the Payne effect when added to rubber. This is not only related to the modified resin disrupting the filler network in the system and improving the dispersion of the filler in the system, but also to reducing the shear modulus of the rubber. Comparative Example 1, due to crosslinking, increases the softening point and thus increases the shear modulus, resulting in a lower reduction in the Payne effect than Example 1. Comparative Example 3 lacks chemical bonds from silane to the filler silica, which fails to improve the dispersion of the filler in the system, resulting in a poor reduction in the filler network effect. Comparative Example 6 disrupts the filler network effect through 3-isocyanate propyltrimethoxysilane, but because the silane itself is a small molecule, it eliminates its own effect on reducing the Payne effect.

[0071] In Table 3, tanδ at 0℃ has a certain correlation with anti-slip performance, while tanδ at 60℃ corresponds to sliding resistance. The BPST test is a comprehensive test of material hysteresis friction and adhesive friction. From the test results, the BPST test results are basically consistent with the tanδ value at 0℃. From the test results of Examples 1 to 7, it can be seen that the addition of modified hydrogenated petroleum resin improves the dispersion of fillers in the system, which increases the tanδ value of rubber at 0℃ and significantly improves the hysteresis friction performance of the system. This gives the system good anti-slip performance while having low sliding resistance. The higher softening point of Comparative Example 1 causes the glass transition temperature of the system to move to a higher temperature, and the tanδ at 60℃ also increases accordingly. Although it improves the anti-slip performance of rubber, it also increases the rolling resistance of the system. The addition of resin in Comparative Example 3 increases the tanδ at 0℃, but the tanδ at 60℃ also increases accordingly. This may be because the lack of silane to disperse silica and the disruption of the filler network increases the rolling resistance of the system.

[0072] Furthermore, the modified hydrogenated petroleum resin prepared by this invention effectively disperses stress and improves tensile strength and tear strength by utilizing chemical bonds to disperse the filler and form an integral whole with various parts of the rubber.

[0073] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the present invention. Any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the scope of the present invention.

Claims

1. A method for preparing a modified hydrogenated petroleum resin for rubber tires, characterized in that, The process includes the following steps: adding hydrogenated petroleum resin, N-substituted maleimide, and initiator into a twin-screw extruder for a melt grafting reaction, followed by two-stage devolatilization in the devolatilization section and the drop-strip devolatilizer of the twin-screw extruder to obtain modified hydrogenated petroleum resin; The hydrogenated petroleum resin is a petroleum resin that has undergone hydrogenation treatment, with a hydrogenation rate of 30-50%. The N-substituted maleimide has an alkoxy group and can be grafted onto the hydrogenated petroleum resin through its carbon-carbon double bond.

2. The method for preparing a modified hydrogenated petroleum resin for rubber tires according to claim 1, characterized in that, The reaction section conditions of the twin-screw extruder include: temperatures of 170~180℃, 180~190℃, 190~200℃, and 200~210℃ respectively, and a total residence time of 5~10 min. The devolatilization section conditions of the twin-screw extruder include: a temperature of 205~215℃, an absolute pressure of 2~3 kPa, and a residence time of 2~3 min. The conditions of the strip-type devolatilizer include: an internal temperature of 235~245℃, an absolute pressure of 1~1.5 kPa, and a strip falling time of 10~20 s.

3. The method for preparing a modified hydrogenated petroleum resin for rubber tires according to claim 1, characterized in that, Based on 100 parts of hydrogenated petroleum resin: 0.5-3 parts of N-substituted maleimide and 0.1-0.2 parts of initiator.

4. The method for preparing a modified hydrogenated petroleum resin for rubber tires according to claim 1, characterized in that, The initiator includes at least one of dicumyl peroxide, di-tert-butyl peroxide, and dibenzoyl peroxide.

5. The method for preparing a modified hydrogenated petroleum resin for rubber tires according to claim 1, characterized in that, The preparation method of the hydrogenated petroleum resin includes: adding a catalyst and petroleum resin to a high-pressure reactor, sealing the reactor, purging with nitrogen, heating to 200~220℃ with stirring, then purging the nitrogen with hydrogen, controlling the reaction pressure to 2~3MPa, continuously adding hydrogen, measuring the bromine value, calculating that the hydrogenation rate reaches 30~50%, ending the reaction, removing the catalyst, and obtaining the hydrogenated petroleum resin by distillation.

6. The method for preparing a modified hydrogenated petroleum resin for rubber tires according to claim 5, characterized in that, The petroleum resin includes at least one of C5 petroleum resin and C9 petroleum resin, and the catalyst includes at least one of Ni / γ-Al2O3, Ni / C, Pt / γ-Al2O3, Pt / C, and Pd / C, with the catalyst addition amount being 1~2 wt% petroleum resin.

7. The method for preparing a modified hydrogenated petroleum resin for rubber tires according to claim 1, characterized in that, The preparation method of the N-substituted maleimide includes the following steps: under a nitrogen atmosphere, isocyanate silane and solvent are added to a flask, followed by the addition of maleic anhydride, the temperature is raised to 80~100℃, and the reaction is maintained for 6~10h. After the reaction is completed, the N-substituted maleimide is obtained by filtration and drying.

8. The method for preparing a modified hydrogenated petroleum resin for rubber tires according to claim 7, characterized in that, The mass ratio of the isocyanate silane to maleic anhydride is 1:0.3~0.

5.

9. The method for preparing a modified hydrogenated petroleum resin for rubber tires according to claim 7, characterized in that, The isocyanate silane includes at least one of 3-isocyanate propyltrimethoxysilane, 3-isocyanate propyltriethoxysilane, and 3-isocyanate propylmethyldimethoxysilane, and the solvent includes at least one of N,N-dimethylformamide, N,N-dimethylacetamide, and N-methylpyrrolidone.

10. A modified hydrogenated petroleum resin for rubber tires obtained by the preparation method of the modified hydrogenated petroleum resin for rubber tires according to any one of claims 1 to 9.

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