Preparation method of modified biphase carbon black wet-process rubber compound

Abstract

The invention discloses a preparation method of a modified biphase carbon black wet-process rubber compound, and relates to the field of rubber processing. The preparation method comprises the following steps: firstly, carrying out surface modification on carbon black, and compounding with reactive white carbon black to prepare modified biphase carbon black; and mixing rubber latex with the modified biphase carbon black slurry, and flocculating to obtain the modified biphase carbon black filled wet-process rubber compound. After the carbon black is modified, the agglomeration phenomenon is weakened, and the acting force between the carbon black and the reactive white carbon black is enhanced; the dispersity and the stability of the prepared modified biphase carbon black in latex are improved, and the carbon black and the white carbon black can realize synchronous flocculation in the latex, so that the loss of the filler and the latex is reduced, and the flocculation process is controllable. According to the method, the energy consumption in the traditional mixing process can be effectively reduced, and the prepared wet-process rubber compound has excellent processability and mechanical property.

Description

Technical Field

[0001] The invention belongs to the technical field of rubber processing, and particularly relates to a method for preparing a modified two-phase carbon black wet-mixed rubber. Background Art

[0002] Fillers play a vital role in the rubber industry. In addition to increasing the volume and saving product costs, they can also significantly improve the overall performance of rubber. Commonly used reinforcing fillers are mainly carbon black and silica. Carbon black can improve the mechanical properties and wear resistance of the rubber, but there are problems such as high heat generation and poor anti-skid performance. Silica can reduce the rolling resistance of the rubber and improve the anti-skid performance, but due to the rich hydroxyl groups on its surface, its polarity is high, it is easy to agglomerate, and its compatibility with the rubber is poor, resulting in poor mixing performance of silica. Therefore, in actual formulation applications, carbon black and silica are compounded to play a synergistic reinforcement role.

[0003] The mixing process is a key step in the preparation of rubber nanocomposites, primarily involving the thorough and uniform mixing of raw rubber, fillers, and various additives. The quality of the mixing process directly impacts subsequent processing and product quality. Wet mixing, a recently developed mixing method, involves mixing the latex rubber with a reinforcing filler slurry through stirring, followed by the addition of a flocculant to produce the wet mix. Wet mixing offers low energy consumption and minimal environmental pollution. Furthermore, the filler in the wet mix is well dispersed. Compared to dry-mixed rubber, it exhibits improved mechanical properties and significantly reduced rolling resistance and heat generation.

[0004] Due to differences in surface polarity and compatibility with rubber, carbon black and silica exhibit distinct flocculation effects on latex after mixing with latex. Silica, due to its abundant surface hydroxyl groups, has poor compatibility with non-polar latex, resulting in significant silica filler loss after wet mixing. Carbon black also exhibits self-flocculation in latex, preventing it from maintaining a stable presence in the latex for extended periods, leading to partial latex loss. Due to the significant differences in surface properties and compatibility with latex, compounded dual-phase carbon black is difficult to achieve simultaneous flocculation in latex, resulting in poor dispersion and limiting its application in wet mixing.

[0005] Based on this, this application was developed. Summary of the Invention

[0006] The purpose of the present invention is to overcome the defects of the prior art and provide a method for preparing a modified two-phase carbon black wet-mixed rubber. The method can achieve synchronous flocculation of carbon black and white carbon black, with less loss and simple operation. First, the carbon black is surface-modified to improve the degree of agglomeration of the carbon black itself and the dispersion stability in the latex. On the other hand, by compounding with different types of white carbon black, hydrogen bonding, adsorption, covalent bonding, etc. are achieved between the modified carbon black and the white carbon black, thereby enhancing the binding force between the modified carbon black and the white carbon black and improving the dispersibility and stability of the modified two-phase carbon black in the latex.

[0007] To achieve the above object, the present invention adopts the following technical solutions: A method for preparing a modified two-phase carbon black wet-mixed rubber comprises the following steps: 1) Preparation of modified carbon black: Carbon black is dispersed in water by ultrasonic stirring or emulsification at high speed to obtain a carbon black slurry; a small molecule modifier and a macromolecular modifier are sequentially added to the carbon black slurry, and the mixture is heated and stirred for a certain period of time to obtain a modified carbon black slurry, which is then subjected to solid-liquid separation and washing to obtain the modified carbon black; 2) Preparation of modified dual-phase carbon black: The modified carbon black prepared in step 1) and reactive silica are added with water to prepare a slurry with a mass fraction of 5-20%, and the slurry is dispersed and emulsified or subjected to ultrasonic stirring for a certain period of time to obtain a modified dual-phase carbon black slurry; 3) Preparation of a modified dual-phase carbon black wet mix: The modified dual-phase carbon black slurry obtained in step 2) is added to the latex and mixed thoroughly. A flocculant is then added and flocculated under mechanical stirring. The flocculent is sheeted, washed, crushed, and dried to obtain the modified dual-phase carbon black wet mix. Processing aids such as accelerators and antioxidants are then added. The mix is uniformly mixed on a two-roll mill, thinned, and sheeted. The mix is then allowed to stand and vulcanized on a flat vulcanizer. The properties of the rubber compound are then tested.

[0008] Specifically, the carbon black used may include standard commercial carbon black such as N115, N220, N330, and pyrolysis carbon black.

[0009] Furthermore, the preparation of the carbon black slurry includes the following two methods: Method 1: high-speed stirring ultrasonic dispersion treatment, the ultrasonic frequency is 200~4000Hz, the ultrasonic time is 0.5~2h, and the stirring speed is 600~3000r / min; Method 2: Emulsification dispersion treatment, the emulsification time is 0.5~2h, and the rotation speed is 600~2500r / min.

[0010] Specifically, the mass fraction of carbon black in the carbon black slurry can be 3-8%, the mass ratio of carbon black to small molecule modifier can be 1:0.02-0.2, and the mass ratio of carbon black to macromolecular modifier can be 1:0.01-0.2. To achieve better dispersion effect, the small molecule modifier can be first dispersed in ethanol and then added to the carbon black slurry.

[0011] Specifically, the small molecule modifier can be at least one of small molecule substances containing hydrophobic functional groups such as γ-methacryloxypropyltrimethoxysilane, γ-glycidyloxypropyltrimethoxysilane, bis-[γ-(triethoxysilyl)propyl]tetrasulfide, vinyltriethoxysilane, dimethyldiethoxysilane, γ-aminopropyltriethoxysilane, and hexamethyldisilazane; the macromolecular modifier can be at least one of polymers such as polyacrylic acid, polymethacrylic acid, polyvinyl acetate, polyethylene glycol, polymaleic acid, polymaleic anhydride, polyacrylamide, and polyvinyl alcohol.

[0012] Furthermore, in step 1), the reaction temperature during the preparation of the modified carbon black can be 30-85° C., wherein the modification time of the small molecule modifier is 0.5-3 h, and the modification time of the macromolecular modifier is 0.5-2 h.

[0013] Specifically, in step 1), the silica used is reactive silica, whose surface is modified with organic functional groups such as alkyl groups, amino groups, double bonds, and epoxy groups. Reactive silica refers to nano-silica that has been modified with surface technology to have active organic functional groups on its surface. It is sourced from the Henan Nanomaterials Engineering Research Center.

[0014] Specifically, in step 2), in the preparation of the modified dual-phase carbon black slurry, the mass fraction of the modified dual-phase carbon black can be 6-15%, the mass ratio of the modified carbon black to the reactive silica can be arbitrarily adjusted, and the emulsification or ultrasonic stirring treatment time can be 0.5-2h.

[0015] Furthermore, the latex used can be one or more of natural rubber latex, styrene-butadiene latex, or latex obtained by emulsion polymerization of monomers, and the mass fraction of rubber in the latex is 6-30%.

[0016] Furthermore, the flocculant used in preparing the wet mixed rubber can be at least one of metal salts such as formic acid, acetic acid, sodium chloride, and calcium chloride. The amount of the flocculant can be 3-15% of the mass fraction of the dry rubber. The mechanical stirring speed during flocculation can be 500-3000 r / min.

[0017] The present invention proposes a method for preparing a modified two-phase carbon black wet-mix rubber, which has the following characteristics: 1. After the carbon black is surface-modified, the agglomeration phenomenon between the carbon black particles is weakened, and the dispersion stability of the carbon black in the latex is improved; 2. Reactive silica and the modified carbon black are compounded, and hydrogen bonds, physical adsorption effects or covalent bonds are formed between the silica with different active groups on the surface and the functional groups on the surface of the modified carbon black. On the one hand, the agglomeration between the carbon black and the carbon black particles and between the silica and the silica particles is improved, and the binding force between the carbon black and the silica particles is enhanced. On the other hand, the organic functional groups (groups) modified on the surface of the modified two-phase carbon black effectively improve the compatibility with the rubber material; 3. The prepared modified two-phase carbon black achieves synchronous flocculation in the latex, and the wet mixing process is simple and the flocculation process is controllable.

[0018] Compared with the prior art, the present invention has the following advantages and beneficial effects: 1. The present invention provides a method for preparing a modified duplex carbon black. First, by surface-modifying the carbon black, the carbon black's agglomeration and dispersion stability in latex are improved. Second, by compounding the modified carbon black with different types of silica, hydrogen bonding, adsorption, and covalent bonding are achieved between the modified carbon black and silica, enhancing the binding force between the modified carbon black and silica, and improving the dispersibility and stability of the modified duplex carbon black in latex.

[0019] 2. The modified dual-phase carbon black prepared by the present invention can achieve synchronous flocculation in latex, and the loss of latex and filler after flocculation is small. The preparation process of the modified dual-phase carbon black wet-mixed rubber is simple and the flocculation process is controllable.

[0020] 3. The preparation process of the present invention can realize the preparation of dual-phase carbon black with any proportion and multiple types of carbon black and white carbon black, which is beneficial to broaden the application scenarios of dual-phase carbon black rubber composite materials; on the other hand, the modified dual carbon black of the present invention is applied to wet mixing. Compared with the traditional dry mixing, the tensile strength is increased by 8.23%, the 300% modulus stress is increased by 24.54%, and the tear strength is increased by 10.12%. The rolling resistance of the rubber is reduced, and the overall performance of the rubber is improved. BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 Transmission electron micrographs of the modified duplex carbon black prepared in Example 1 (left) and Comparative Example 1 (right). DETAILED DESCRIPTION

[0021] The technical solution of the present invention is further described in detail below in conjunction with the embodiments, but the protection scope of the present invention is not limited thereto.

[0022] In the following examples, the raw materials used are all common commercial products that can be purchased directly, or can be prepared using conventional techniques in the art.

[0023] Normal temperature refers to 25±5℃.

[0024] Example 1 A method for preparing a modified two-phase carbon black wet-mixed rubber comprises the following steps: Based on the carbon black N220 dry powder content of 100phr, 100phr carbon black was weighed, and then the above substance was added to 1700phr distilled water, and ultrasonic dispersion was performed to obtain a carbon black slurry. 20phr ethanol and 5phr hexamethyldisilazane were mixed evenly and added to the slurry. After reacting at 65°C for 1h, 2phr polyvinyl acetate was added and reacted for 1h. After filtration and multiple washing, modified carbon black was obtained.

[0025] Take 100 phr of dry powder of white carbon black (WCB-B, produced by Henan Heda Nanomaterial Engineering Research Center Co., Ltd.) with double bonds modified on the surface; add water to the obtained modified carbon black and the above-mentioned white carbon black to prepare a slurry with a mass fraction of 10%, and then mix and ultrasonically stir for 1 hour to obtain a modified dual-phase carbon black slurry DCB-1.

[0026] Based on 100 phr of the dry rubber content of the natural rubber latex, 50 phr of the dual-phase carbon black slurry DCB-1 prepared in Example 1, calculated as the dual-phase carbon black dry powder content, was dispersed into natural rubber latex with a solid content of 20%, and stirred to mix evenly. 5 phr of calcium chloride flocculant was added at room temperature at a rotation speed of 1000 rad / min, and the latex was flocculated under mechanical stirring. The flocculent was flaked, washed, crushed, and dried to obtain a dual-phase carbon black / NR composite material.

[0027] The above-mentioned dual-phase carbon black DCB-1 / NR composite material 150phr, silane coupling agent Si 69 5phr, zinc oxide 5phr, stearic acid 1.5phr, microcrystalline wax 1.5phr, antioxidant 4020 1.5phr, accelerator CZ 1phr, accelerator D 2phr, sulfur 1.5phr, mix evenly, thin pass, unroll, stand for 12h, vulcanize under the conditions of 150℃×20MPa×(Tc90+3min), test the mechanical properties, the results are shown in Table 1.

[0028] Comparative Example 1 Based on the carbon black N220 dry powder content of 100phr, 100phr carbon black was weighed, and then the above substance was added to 1700phr distilled water, and ultrasonic dispersion was performed to obtain a carbon black slurry. 20phr ethanol and 5phr hexamethyldisilazane were mixed evenly and added to the slurry. After reacting at 65°C for 1h, 2phr polyvinyl acetate was added and reacted for 1h. After filtration and multiple washing, modified carbon black was obtained.

[0029] Take 100 phr of ordinary silica powder without surface modification (produced by Henan Heda Nanomaterial Engineering Research Center Co., Ltd., WCB); add water to the obtained modified carbon black and the above silica to prepare a slurry with a mass fraction of 10%, and then mix and ultrasonically stir for 1 hour to obtain a modified dual-phase carbon black slurry DCB-0.

[0030] Based on the dry rubber content of the natural rubber latex of 100 phr, 50 phr of the dual-phase carbon black slurry DCB-0 prepared above, calculated as the dry powder content of the modified dual-phase carbon black, was dispersed into natural rubber latex with a solid content of 20% and stirred to mix evenly. 5 phr of calcium chloride flocculant was added at room temperature at a rotation speed of 1000 rad / min, and the latex was flocculated under mechanical stirring. The flocculent was creped, washed, crushed, and dried to obtain a modified dual-phase carbon black DCB-0 / NR composite material.

[0031] The modified dual-phase carbon black DCB-0 / NR composite material 150phr, silane coupling agent Si 69 5phr, zinc oxide 5phr, stearic acid 1.5phr, microcrystalline wax 1.5phr, antioxidant 4020 1.5phr, accelerator CZ 1phr, accelerator D 2phr, sulfur 1.5phr, mix evenly, thin pass, unroll, stand for 12h, vulcanize under the conditions of 150℃×20MPa×(Tc90+3min), test the mechanical properties, the results are shown in Table 1.

[0032] Figure 1 Transmission electron micrographs of the modified dual-phase carbon black prepared in Example 1 (left) and Comparative Example 1 (right). Compared to Comparative Example 1, the dual-phase carbon black prepared in Example 1 achieves a dual-phase dispersion effect of carbon black and silica, effectively reducing nanoparticle agglomeration. This significantly promotes the dispersion of nanofillers in latex.

[0033] Comparative Example 2 Based on the natural rubber content of 100phr, 50phr of dual-phase carbon black DCB-1 dry powder was taken and mixed with the processing aid silane coupling agent Si 69 5phr, zinc oxide 5phr, stearic acid 1.5phr, microcrystalline wax 1.5phr, antioxidant 4020 1.5phr, accelerator CZ 1phr, accelerator D 2phr, sulfur 1.5phr, mixed evenly on an open mill, thinned, unrolled, parked for 12h, vulcanized under the conditions of 150℃×20MPa×(Tc90+3min), and tested for mechanical properties. The results are shown in Table 1.

[0034] Example 2 A method for preparing a modified two-phase carbon black wet-mixed rubber comprises the following steps: Based on the carbon black N220 dry powder content of 100phr, 100phr carbon black was weighed and then added to 1700phr distilled water. Ultrasonic dispersion was performed to obtain a carbon black slurry. 20phr ethanol and 5phr hexamethyldisilazane were mixed evenly and added to the slurry. After reacting at 65°C for 1h, 1phr polyvinyl acetate was added and reacted for 1h. The product was filtered and washed multiple times to obtain modified carbon black.

[0035] Take 100 phr of dry powder of white carbon black (WCB-B, produced by Henan Heda Nanomaterial Engineering Research Center Co., Ltd.) with double bonds modified on the surface; add water to the obtained modified carbon black and the above-mentioned white carbon black to prepare a slurry with a mass fraction of 10%, and then mix and ultrasonically stir for 1 hour to obtain a modified dual-phase carbon black slurry DCB-2.

[0036] Based on 100 phr of the dry rubber content of the natural rubber latex, 50 phr of the dual-phase carbon black slurry DCB-2 prepared in Example 2, calculated as the dual-phase carbon black dry powder content, was dispersed into natural rubber latex with a solid content of 20% and stirred to mix evenly. 5 phr of calcium chloride flocculant was added at room temperature at a rotation speed of 1000 rad / min, and the latex was flocculated under mechanical stirring. The flocculent was creped, washed, crushed, and dried to obtain a dual-phase carbon black DCB-2 / NR composite material.

[0037] The above-mentioned dual-phase carbon black DCB-2 / NR composite material 150phr, silane coupling agent Si 69 5phr, zinc oxide 5phr, stearic acid 1.5phr, microcrystalline wax 1.5phr, antioxidant 4020 1.5phr, accelerator CZ 1phr, accelerator D 2phr, sulfur 1.5phr, mix evenly, thin pass, unroll, stand for 12h, vulcanize under the conditions of 150℃×20MPa×(Tc90+3min), test the mechanical properties, the results are shown in Table 1.

[0038] Example 3 A method for preparing a modified two-phase carbon black wet-mixed rubber comprises the following steps: Based on the carbon black N220 dry powder content of 100 phr, 100 phr of carbon black was weighed, and then the above substance was added to 1700 phr of distilled water, and ultrasonic dispersion was performed to obtain a carbon black slurry. 20 phr of ethanol and 5 phr of hexamethyldisilazane were mixed evenly and added to the slurry. After reacting at 65°C for 1 hour, 2 phr of polyvinyl alcohol was added, and the mixture was reacted for 1 hour. The mixture was filtered and washed multiple times to obtain modified carbon black.

[0039] Take 100 phr of dry powder of white carbon black (WCB-B, produced by Henan Heda Nanomaterial Engineering Research Center Co., Ltd.) with double bonds modified on the surface; add water to the obtained modified carbon black and the above-mentioned white carbon black to prepare a slurry with a mass fraction of 10%, and then mix and ultrasonically stir for 1 hour to obtain a modified dual-phase carbon black slurry DCB-3.

[0040] Based on 100 phr of the dry rubber content of the natural rubber latex, 50 phr of the dual-phase carbon black slurry DCB-3 prepared in Example 3, calculated as the dual-phase carbon black dry powder content, was dispersed into natural rubber latex with a solid content of 20%, and stirred to mix evenly. 5 phr of calcium chloride flocculant was added at room temperature at a rotation speed of 1000 rad / min, and the latex was flocculated under mechanical stirring. The flocculent was flaked, washed, crushed, and dried to obtain a dual-phase carbon black DCB-3 / NR composite material.

[0041] The above-mentioned dual-phase carbon black DCB-3 / NR composite material 150phr, silane coupling agent Si 69 5phr, zinc oxide 5phr, stearic acid 1.5phr, microcrystalline wax 1.5phr, antioxidant 4020 1.5phr, accelerator CZ 1phr, accelerator D 2phr, sulfur 1.5phr, mix evenly, thin pass, unroll, stand for 12h, vulcanize under the conditions of 150℃×20MPa×(Tc90+3min), test the mechanical properties, the results are shown in Table 1.

[0042] Example 4 A method for preparing a modified two-phase carbon black wet-mixed rubber comprises the following steps: Based on the carbon black N220 dry powder content of 100phr, 100phr carbon black was weighed, and then the above substance was added to 1700phr distilled water, and ultrasonic dispersion was performed to obtain a carbon black slurry. 20phr ethanol and 5phr vinyltriethoxysilane were mixed evenly and added to the slurry. After reacting at 65°C for 1h, 2phr polyvinyl acetate was added and reacted for 1h. The mixture was filtered and washed multiple times to obtain modified carbon black.

[0043] Take 100 phr of dry powder of amino-modified white carbon black (produced by Henan Heda Nanomaterial Engineering Research Center Co., Ltd., WCB-N); add water to the obtained modified carbon black and the above-mentioned white carbon black to prepare a slurry with a mass fraction of 10%, and then mix and ultrasonically stir for 1 hour to obtain a modified dual-phase carbon black slurry DCB-4.

[0044] Based on 100 phr of dry rubber content in the natural rubber latex, 50 phr of the dual-phase carbon black slurry DCB-4 prepared in Example 4, calculated as the dual-phase carbon black dry powder content, was dispersed into natural rubber latex having a solid content of 20% and stirred to mix evenly. 5 phr of calcium chloride flocculant was added at room temperature at a rotation speed of 1000 rad / min, and the latex was flocculated under mechanical stirring. The flocculent was flaked, washed, crushed, and dried to obtain a dual-phase carbon black DCB-4 / NR composite material.

[0045] The above-mentioned dual-phase carbon black DCB-4 / NR composite material 150phr, silane coupling agent Si 69 5phr, zinc oxide 5phr, stearic acid 1.5phr, microcrystalline wax 1.5phr, antioxidant 4020 1.5phr, accelerator CZ 1phr, accelerator D 2phr, sulfur 1.5phr, mix evenly, thin pass, unroll, stand for 12h, vulcanize under the conditions of 150℃×20MPa×(Tc90+3min), test the mechanical properties, the results are shown in Table 1.

[0046] Example 5 A method for preparing a modified two-phase carbon black wet-mixed rubber comprises the following steps: Based on the carbon black N220 dry powder content of 100phr, 100phr carbon black was weighed, and then the above substance was added to 1700phr distilled water, and ultrasonic dispersion was performed to obtain a carbon black slurry. 20phr ethanol and 5phr hexamethyldisilazane were mixed evenly and added to the above slurry. After reacting at 65°C for 1h, 2ph polyvinyl acetate was added and reacted for 1h. The mixture was filtered and washed multiple times to obtain modified carbon black.

[0047] Take 150 phr of dry powder of epoxy-modified white carbon black (produced by Henan Heda Nanomaterial Engineering Research Center Co., Ltd., WCB-E); add water to the obtained modified carbon black and the above-mentioned white carbon black to prepare a slurry with a mass fraction of 10%, and then mix and ultrasonically stir for 1 hour to obtain a modified dual-phase carbon black slurry DCB-5.

[0048] Based on 100 phr of the dry rubber content of the natural rubber latex, 50 phr of the dual-phase carbon black slurry DCB-5 prepared in Example 5, calculated as the dual-phase carbon black dry powder content, was dispersed into natural rubber latex with a solid content of 20%, and stirred to mix evenly. 5 phr of calcium chloride flocculant was added at room temperature at a rotation speed of 1000 rad / min, and the latex was flocculated under mechanical stirring. The flocculent was flaked, washed, crushed, and dried to obtain a dual-phase carbon black DCB-5 / NR composite material.

[0049] The above-mentioned dual-phase carbon black DCB-5 / NR composite material 150phr, silane coupling agent Si 695phr, zinc oxide 5phr, stearic acid 1.5phr, microcrystalline wax 1.5phr, antioxidant 4020 1.5phr, accelerator CZ 1phr, accelerator D 2phr, sulfur 1.5phr, mix evenly, thin pass, unroll, stand for 12h, vulcanize under the conditions of 150℃×20MPa×(Tc90+3min), test the mechanical properties, the results are shown in Table 1.

[0050] Example 6 A method for preparing a modified two-phase carbon black wet-mixed rubber comprises the following steps: Based on the carbon black N220 dry powder content of 100phr, 100phr carbon black was weighed, and then the above substance was added to 1700phr distilled water, and ultrasonic dispersion was performed to obtain a carbon black slurry. 20phr ethanol and 5phr dimethyldiethoxysilane were mixed evenly and added to the above slurry. After reacting at 65°C for 1h, 2phr polyvinyl acetate was added and reacted for 1h. The mixture was filtered and washed multiple times to obtain modified carbon black.

[0051] Take 400 phr of dry powder of white carbon black (WCB-B) with double bonds modified on the surface; add water to the obtained modified carbon black and the above-mentioned white carbon black to prepare a slurry with a mass fraction of 10%, and then mix and ultrasonically stir for 1 hour to obtain a modified dual-phase carbon black slurry DCB-6.

[0052] Based on 100 phr of dry rubber content in the natural rubber latex, 50 phr of the dual-phase carbon black slurry DCB-6 prepared in Example 6, calculated as the dual-phase carbon black dry powder content, was dispersed into natural rubber latex having a solid content of 20% and stirred to mix evenly. 5 phr of calcium chloride flocculant was added at room temperature at a rotation speed of 1000 rad / min, and the latex was flocculated under mechanical stirring. The flocculent was flaked, washed, crushed, and dried to obtain a dual-phase carbon black DCB-6 / NR composite material.

[0053] The above-mentioned dual-phase carbon black DCB-6 / NR composite material 150phr, silane coupling agent Si 69 5phr, zinc oxide 5phr, stearic acid 1.5phr, microcrystalline wax 1.5phr, antioxidant 4020 1.5phr, accelerator CZ 1phr, accelerator D 2phr, sulfur 1.5phr, mix evenly, thin pass, unroll, stand for 12h, vulcanize under the conditions of 150℃×20MPa×(Tc90+3min), test the mechanical properties, the results are shown in Table 1.

[0054] Table 1 Properties of modified dual-phase carbon black / natural rubber composites Table 1 shows the properties of the rubber composites from the aforementioned examples and comparative examples. It demonstrates that: first, the modified dual-phase carbon black can effectively improve the overall mechanical properties of the rubber composite. Second, the provided method for preparing a modified dual-phase carbon black wet-mix rubber can produce a wet-mix masterbatch with excellent overall performance. Compared to conventional dry-mixing processes, the resulting rubber composite exhibits an 8.24% increase in tensile strength and a 10.3% increase in tear strength. Furthermore, the rubber composite effectively improves the difficult balance between wet-slip performance (a higher Tanδ 0°C value indicates better wet-slip performance) and rolling resistance (a lower Tanδ 60°C value indicates lower rolling resistance).

Claims

1. A method for preparing a modified dual-phase carbon black wet mix rubber, characterized in that: The following steps are involved: 1) Preparation of modified carbon black: Carbon black is dispersed in water to obtain a carbon black slurry; a small molecule modifier and a macromolecular modifier are added to the carbon black slurry, and the mixture is heated and stirred for a certain period of time to obtain a modified carbon black slurry, which is then subjected to solid-liquid separation and washing to obtain the modified carbon black; 2) Preparation of modified dual-phase carbon black: The modified carbon black prepared in step 1) and reactive silica are added with water to prepare a slurry with a mass fraction of 5-20%, and the slurry is dispersed and emulsified or subjected to ultrasonic stirring for a certain period of time to obtain a modified dual-phase carbon black slurry; 3) Preparation of modified dual-phase carbon black wet mix: Add the modified dual-phase carbon black slurry obtained in step 2) to latex, mix well, add a flocculant, and complete flocculation under mechanical stirring; the flocculent is creped, washed, crushed, and dried to obtain the product.

2. The preparation method according to claim 1, characterized in that The carbon black used includes standard commercial carbon black such as N115, N220, N330 and pyrolysis carbon black.

3. The preparation method according to claim 1, characterized in that The preparation of the carbon black slurry includes the following two methods: Method 1: high-speed stirring ultrasonic dispersion treatment, the ultrasonic frequency is 200~4000Hz, the ultrasonic time is 0.5~2h, and the stirring speed is 600~3000r / min; Method 2: Emulsification dispersion treatment, the emulsification time is 0.5~2h, and the rotation speed is 600~2500r / min.

4. The preparation method according to claim 1, characterized in that The mass fraction of carbon black in the carbon black slurry is 3-8%, the mass ratio of carbon black to small molecule modifier is 1:0.02-0.2, and the mass ratio of carbon black to macromolecular modifier is 1:0.01-0.

2.

5. The preparation method according to claim 1, characterized in that The small molecule modifier is at least one of small molecule substances containing hydrophobic functional groups, such as γ-methacryloxypropyltrimethoxysilane, γ-glycidyloxypropyltrimethoxysilane, bis-[γ-(triethoxysilyl)propyl]tetrasulfide, vinyltriethoxysilane, dimethyldiethoxysilane, γ-aminopropyltriethoxysilane, and hexamethyldisilazane; the macromolecular modifier is at least one of polymers, such as polyacrylic acid, polymethacrylic acid, polyvinyl acetate, polyethylene glycol, polymaleic acid, polymaleic anhydride, polyacrylamide, and polyvinyl alcohol.

6. The preparation method according to claim 1, characterized in that In step 1), the reaction temperature during the preparation of modified carbon black is 30-85° C., wherein the modification time of the small molecule modifier is 0.5-3 h, and the modification time of the macromolecular modifier is 0.5-2 h.

7. The preparation method according to claim 1, characterized in that In step 1), the silica used is reactive silica, the surface of which is modified with organic functional groups such as alkyl, amino, double bond, and epoxy.

8. The preparation method according to claim 1, characterized in that In step 2), in the preparation of the modified dual-phase carbon black slurry, the mass fraction of the modified dual-phase carbon black is 6-15%, the mass ratio of the modified carbon black to the reactive silica can be adjusted arbitrarily, and the emulsification or ultrasonic stirring treatment time is 0.5-2h.

9. The preparation method according to claim 1, characterized in that The latex used is one or more of natural rubber latex, styrene-butadiene latex or latex obtained by monomer emulsion polymerization, and the mass fraction of rubber in the latex is 6-30%.

10. The preparation method according to claim 1, characterized in that The flocculant used in preparing the wet mixed rubber is at least one of formic acid, acetic acid, metal salt, etc., and the amount of the flocculant is 3-15% of the mass fraction of the rubber dry rubber. The mechanical stirring speed during flocculation is 500-3000r / min.

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