Rubber composite material, preparation method and application thereof, rubber compound and application thereof

Abstract

The invention belongs to the field of rubber composite materials, and particularly relates to a rubber composite material, a preparation method and application thereof, a rubber compound and application thereof. The rubber composite material provided by the invention comprises silicon dioxide and silane modified liquid 1, 4-polybutadiene grafted on the surface of the silicon dioxide, and the specific surface area of the silicon dioxide is 3-50m < 2 > / g. The specific surface area of the silicon dioxide is relatively low, so that the silicon dioxide has relatively low surface energy; the silane modified liquid 1, 4-polybutadiene can react with silicon hydroxyl in the white carbon black, so that the binding capacity of the white carbon black and a rubber matrix is improved; when the rubber composite material is used as the processing aid, the dispersibility of the white carbon black in the rubber can be improved, the filler agglomeration phenomenon is reduced, and the white carbon black can play a role, so that the wet skid resistance and wear resistance of the rubber material are improved, and the rolling resistance is reduced.

Description

Technical Field

[0001] This invention belongs to the field of rubber composite material technology, specifically relating to a rubber composite material and its preparation method and application, and a compound rubber and its application. Background Technology

[0002] In recent years, with the development of energy conservation and emission reduction policies and "green tire" technology, silica has gradually become the main reinforcing filler in tire treads. Compared with traditional carbon black systems, silica can significantly reduce hysteresis loss in rubber compounds, reduce tire rolling resistance, improve vehicle fuel economy, and reduce carbon dioxide emissions.

[0003] However, silica has a surface rich in hydroxyl groups, exhibiting strong polarity, while commonly used tire rubber matrices (such as styrene-butadiene rubber, butadiene rubber, and natural rubber) are non-polar materials, resulting in poor compatibility between the two. Silica is prone to agglomeration during compounding, making dispersion difficult and leading to high processing energy consumption. With further increases in silica usage, agglomeration and dispersion problems become more pronounced, leading to a decline in material performance and limiting the potential for optimizing tire rolling resistance. Summary of the Invention

[0004] In view of this, the present invention provides a rubber composite material, its preparation method and application, and a compound rubber and its application.

[0005] To address the aforementioned technical problems, this invention provides a rubber composite material comprising silica and silane-modified liquid 1,4-polybutadiene grafted onto the surface of the silica; the silica having a specific surface area of ​​3-50 m² / g. 2 / g.

[0006] Preferably, the particle size of the silica is 500-5000 mesh; The silane-modified liquid 1,4-polybutadiene has a silane grafting amount of 10-20%; the purity of the silane-modified liquid 1,4-polybutadiene is above 93%.

[0007] The present invention also provides a method for preparing the rubber composite material described in the above technical solution, comprising the following steps: Rice husks are calcined to obtain a calcined product, which includes silicon dioxide. The calcined product and silane-modified liquid 1,4-polybutadiene were mixed and then subjected to a grafting reaction to obtain the rubber composite material.

[0008] Preferably, the calcination temperature is 450~800℃ and the time is 1~3h.

[0009] Preferably, the mass percentage of silicon dioxide in the calcined product is 60% or more.

[0010] Preferably, the mass ratio of the silica to the silane-modified liquid 1,4-polybutadiene is 1:0.5~1.5.

[0011] Preferably, the grafting reaction is carried out at a temperature of 150~170℃ for a time of 0.5~2h; the grafting reaction is carried out under a protective atmosphere.

[0012] The present invention also provides the application of the rubber composite material described in the above technical solution or the rubber composite material prepared by the preparation method described in the above technical solution as a processing aid for preparing compound rubber.

[0013] The present invention also provides a compound rubber comprising the following raw materials in parts by parts: 100-120 parts of rubber; 80-150 parts of silica; 5-10 parts of silane coupling agent; 1-3 parts stearic acid; 2-4 parts zinc oxide; Anti-aging agent 1-4 parts; Microcrystalline wax 1.5~2.5 parts; Processing aids: 10-30 parts; The processing aid is the rubber composite material described in the above technical solution or the rubber composite material prepared by the preparation method described in the above technical solution.

[0014] The present invention also provides the application of the compound described in the above technical solution in the preparation of rubber tires.

[0015] This invention provides a rubber composite material comprising silica and silane-modified liquid 1,4-polybutadiene grafted onto the surface of the silica; the silica having a specific surface area of ​​3-50 m². 2 / g. In this invention, silica has a low specific surface area and a low surface area; silane-modified liquid 1,4-polybutadiene can react with the silanol groups in silica to improve the bonding ability between silica and rubber matrix; when used as a processing aid, it can improve the dispersibility of silica in rubber, reduce filler agglomeration, and facilitate the function of silica, thereby improving the anti-skid performance and wear resistance of rubber tires while reducing rolling resistance. Attached Figure Description

[0016] Figure 1 Here is an SEM image of the calcined product from Example 1; Figure 2 This is a particle size distribution diagram of silica in the calcined product of Example 1. Detailed Implementation

[0017] The present invention provides a rubber composite material comprising silica and silane-modified liquid 1,4-polybutadiene grafted onto the surface of the silica.

[0018] In this invention, the specific surface area of ​​the silicon dioxide is 3~50m². 2 / g, which can be 6~50m 2 / g, which can be specifically 8m 2 / g, 10m 2 / g, 15m 2 / g、20m 2 / g、40m 2 / g or 45m 2 / g. This invention uses silica with a low specific surface area, which has low surface energy, thus improving dispersion performance.

[0019] In this invention, the particle size of the silicon dioxide can be 500-5000 mesh, or 600-2000 mesh, specifically 600 mesh, 800 mesh, 1000 mesh, 1500 mesh or 3000 mesh.

[0020] In this invention, the amount of silane grafted into the silane-modified liquid 1,4-polybutadiene can be 10-20%, specifically 13%, 15% or 17%.

[0021] The present invention also provides a method for preparing the rubber composite material described in the above technical solution, comprising the following steps: Rice husks are calcined to obtain a calcined product, which includes silicon dioxide. The calcined product and silane-modified liquid 1,4-polybutadiene were mixed and grafted to obtain the rubber composite material.

[0022] This invention involves calcining rice husks to obtain a calcined product, which includes silicon dioxide. In this invention, the calcination temperature can be 450-800℃, specifically 500℃, 550℃, 600℃, or 700℃; the calcination time can be 1-3 hours, specifically 2 hours. In this invention, the calcined product also contains carbon black. The mass percentage of silicon dioxide in the calcined product can be above 60%, and can also be 70-85%, specifically 75% or 80%; the mass percentage of carbon black in the calcined product can be 5-20%, and can also be 10-15%. The silicon dioxide prepared according to the method provided by this invention has a low specific surface area.

[0023] After obtaining the calcined product, the present invention mixes the calcined product with silane-modified liquid 1,4-polybutadiene and performs a grafting reaction to obtain the rubber composite material. In the present invention, the number average molecular weight of the silane-modified liquid 1,4-polybutadiene can be 3500~4500 g / mol, specifically 4000 g / mol; the purity of silane in the silane-modified liquid 1,4-polybutadiene can be above 93%, specifically 94%, 95%, 98% or 99%; the grafting amount of silane in the silane-modified liquid 1,4-polybutadiene can be 10~20%, specifically 13%, 15% or 17%; the silane-modified liquid 1,4-polybutadiene can be purchased from Shandong Debo New Material Technology Co., Ltd.

[0024] In this invention, the mass ratio of silicon dioxide to silane-modified liquid 1,4-polybutadiene can be 1:0.5~1.5, specifically 1:1.

[0025] In this invention, the grafting reaction temperature can be 150~170℃, specifically 160℃; the grafting reaction time can be 0.5~2h, specifically 1h or 1.5h; the grafting reaction can be carried out under a protective atmosphere, which may include nitrogen. In this invention, the silane-modified liquid 1,4-polybutadiene can react with hydroxyl groups on the silica surface and be grafted onto the silica surface.

[0026] The present invention also provides the application of the rubber composite material described in the above technical solution or the rubber composite material prepared by the preparation method described in the above technical solution as a processing aid for preparing compound rubber.

[0027] The present invention also provides a compound rubber comprising the following raw materials in parts by parts: 100-120 parts of rubber; 80-150 parts of silica; 5-10 parts of silane coupling agent; 1-3 parts stearic acid; 2-4 parts zinc oxide; Anti-aging agent 1-4 parts; Microcrystalline wax 1.5~2.5 parts; Processing aids: 10-30 parts; The processing aid is the rubber composite material described in the above technical solution or the rubber composite material prepared by the preparation method described in the above technical solution.

[0028] In this invention, the raw materials for preparing the compound rubber include 100-120 parts of rubber, or 113-117 parts, specifically 115 parts, by mass. In this invention, the rubber may include polystyrene-butadiene rubber (PSB) and natural rubber, and the mass ratio of PSB to natural rubber may be 100:14-16, specifically 100:15.

[0029] In this invention, the raw materials for preparing the compound rubber include 80 to 150 parts of silica by mass, specifically 85, 90, 95, 100, 110, 120, 130, or 140 parts.

[0030] In this invention, the raw materials for preparing the compound rubber include 5 to 10 parts by weight of silane coupling agent, specifically 7, 8, or 9 parts. In this invention, the silane coupling agent may include silane coupling agent Si69 or silane coupling agent Si75.

[0031] In this invention, the raw materials for preparing the compound rubber include 1 to 3 parts of stearic acid, specifically 2 parts, by mass.

[0032] In this invention, the raw materials for preparing the compound rubber include 2 to 4 parts of zinc oxide, specifically 3 parts, by mass.

[0033] In this invention, the raw materials for preparing the compound rubber include 1 to 4 parts by weight of antioxidant, specifically 2 parts, 3 parts, or 3.5 parts. In this invention, the antioxidant may include antioxidant 6PPD.

[0034] In this invention, the raw materials for preparing the compound rubber include 1.5 to 2.5 parts of microcrystalline wax, specifically 2 parts, by mass.

[0035] In this invention, the raw materials for preparing the compound rubber include 10 to 30 parts by mass, specifically 10, 20 or 30 parts; the processing aid is the rubber composite material described in the above technical solution or the rubber composite material prepared by the preparation method described in the above technical solution.

[0036] In this invention, the method for preparing the compound rubber may include the following steps: Rubber, silica, silane coupling agent, stearic acid, zinc oxide, antioxidant, microcrystalline wax, and processing aids are mixed and then subjected to a first compounding process to obtain a primary compound. The primary compound is mixed with sulfur and accelerator, then subjected to a second mixing process, followed by sheeting to obtain the compound.

[0037] This invention involves mixing rubber, silica, silane coupling agent, stearic acid, zinc oxide, antioxidant, microcrystalline wax, and processing aids, followed by a first mixing process to obtain a primary compound. In this invention, when the rubber includes polystyrene-butadiene rubber (PSB) and natural rubber, the PSB and natural rubber can be added to a Banbury mixer, pressed down and held for 30 seconds, and then other materials are added, pressed down and held for another 40 seconds for mixing.

[0038] In this invention, the pressure of the first mixing step can be 48~52 N / cm. 2 Specifically, it can be expressed as 50 N / cm. 2 The temperature of the first mixing can be 140~150℃, specifically 145℃; the time of the first mixing can be 2~4min, specifically 3min.

[0039] In this invention, the first compound can be discharged at 150°C.

[0040] After obtaining the primary compound, the present invention mixes the primary compound with sulfur and an accelerator, performs a second mixing, and then extrudes and presses the compound into sheets to obtain the final compound. In this invention, the mass ratio of rubber to sulfur can be 115:1.3~1.5, specifically 115:1.4 or 115:1.5; the accelerator can include accelerator CBS and / or accelerator DPG, specifically CBS and DPG, or CBS or DPG. When the accelerator is CBS and DPG, the mass ratio of CBS and DPG can be 1:0.8~1.2, specifically 1:1; the mass ratio of rubber to accelerator can be 115:2.

[0041] In this invention, the pressure of the second mixing can be 4~6MPa, specifically 5MPa, and the time of the second mixing can be 1.5~2.5min, specifically 2min.

[0042] In this invention, the temperature for discharging the adhesive can be 108~112℃, specifically 110℃; this invention does not impose any special limitations on the tableting process, and conventional methods in the art can be used.

[0043] This invention also provides the application of the compound described above in the preparation of rubber tires. Tires prepared using the compound provided by this invention exhibit low rolling resistance, good wet skid resistance, and wear resistance. This invention does not impose special requirements on the process of preparing tires using the compound; conventional methods in the art can be used. Specifically, the compound can be molded into a tire carcass, and the tire carcass can be vulcanized to obtain a tire. This invention does not impose special requirements on the molding process; conventional methods in the art can be used. The vulcanization temperature can be 150~170℃, specifically 160℃; the vulcanization time can be 10~40 min, specifically 20 min or 30 min.

[0044] To further illustrate the present invention, the technical solutions provided by the present invention will be described in detail below with reference to the embodiments, but they should not be construed as limiting the scope of protection of the present invention.

[0045] Example 1 Rice husks were calcined at 500℃ for 2 hours to obtain the calcined product. The calcined product contained 80% silicon dioxide by mass, 15% carbon black by mass, and 5% residue. 50g of the calcined product and 50g of silane-modified liquid 1,4-polybutadiene (purity 99%, silane grafting amount 15%) purchased from Shandong Debo New Material Technology Co., Ltd. were mixed and grafted at 160℃ for 1h under nitrogen atmosphere to obtain rubber composite material.

[0046] The mixing was carried out using a meshing internal mixer, with the rotor speed controlled at 40 rpm and the top bolt pressure controlled at 50 N / cm. 2 Add 100 parts of solution-polymerized styrene-butadiene rubber and 15 parts of natural rubber, press the top plug, and hold for 30 seconds. Then add 90 parts of silica, 9 parts of silane coupling agent Si 69, 2 parts of stearic acid, 3 parts of zinc oxide, 3.5 parts of antioxidant 6PPD, 2 parts of microcrystalline wax, and 10 parts of rubber composite material, press the top plug, hold for 40 seconds, keep the temperature constant at 145℃ for 3 minutes, and discharge the rubber at 150℃ to obtain the compound.

[0047] The compound was vulcanized using a tangential internal mixer. The rotor speed of the internal mixer was controlled at 25 rpm, the pressure of the top plug was controlled at 5 MPa, and the temperature of the three zones of the internal mixer was controlled at 35℃. The compound, 1.4 parts sulfur, 2 parts CBS accelerator and 1 part DPG accelerator were added and mixed for 2 min. The compound was then discharged and pressed into sheets at 110℃ to obtain the compound.

[0048] The product after calcination of rice husks was examined by scanning electron microscopy, and the resulting SEM image is shown below. Figure 1 As shown, the obtained silica particle size distribution diagram is as follows: Figure 2 As shown. Figure 1The mass percentages of oxygen, silicon, and carbon in positions 1 to 8 are listed in Table 1.

[0049] Table 1 Figure 1 Mass percentage of elements at different locations

[0050] Combined with Table 1, Figure 1 and Figure 2 It can be seen that the calcined product contains silicon dioxide and carbon black, with the silicon dioxide having a particle size of approximately 20 μm.

[0051] The specific surface area of ​​silica in the calcined product of Example 1 was determined to be 8 m² according to the gas adsorption BET method specified in GB / T 19587-2017. 2 / g, the silica content in Example 1 was 80% as determined by the hydrofluoric acid chemical reaction method.

[0052] Example 2 Rubber composite materials were prepared according to the method in Example 1.

[0053] The compound was prepared by mixing according to the method of Example 1, except that the amount of rubber composite material added was adjusted from 10 parts to 30 parts. The vulcanized compound was prepared according to the method in Example 1.

[0054] Comparative Example 1 The mixing was carried out using a meshing internal mixer, with the rotor speed controlled at 40 rpm and the top bolt pressure controlled at 50 N / cm. 2 Add 100 parts of solution-polymerized styrene-butadiene rubber and 15 parts of natural rubber, press the top plug, and hold for 30 seconds. Then add 105 parts of silica, 9 parts of silane coupling agent Si 69, 2 parts of stearic acid, 3 parts of zinc oxide, 3.5 parts of antioxidant 6PPD, 2 parts of microcrystalline wax, and 15 parts of environmentally friendly aromatic oil. Press the top plug, hold for 40 seconds, keep the temperature constant at 145°C for 3 minutes, and discharge the rubber at 150°C to obtain the compound.

[0055] The compound was vulcanized using a tangential internal mixer. The rotor speed of the internal mixer was controlled at 25 rpm, the pressure of the top plug was controlled at 5 MPa, and the temperature of the three zones of the internal mixer was controlled at 35℃. The compound, 1.4 parts sulfur, 2 parts CBS accelerator and 1 part DPG accelerator were added and mixed for 2 min. The compound was then discharged and pressed into sheets at 110℃ to obtain vulcanized compound.

[0056] Comparative Example 2 The vulcanized compound was prepared according to Comparative Example 1, except that 15 parts of environmentally friendly aromatic oil were replaced with 5 parts of commercially available silane-terminated liquid polybutadiene STE-60.

[0057] The rubber compounds prepared in Examples 1-2 and Comparative Examples 1-2 were vulcanized at 160℃ for 20 min to prepare vulcanized sheets, and relevant performance tests were performed. The results are detailed in Table 2. Mechanical property testing was performed in accordance with GB / T528-2009; hardness testing of vulcanized rubber compounds was performed in accordance with GB / T6031-1998; dynamic thermomechanical analysis temperature: -80℃~90℃, deformation: 0.5%, frequency: 10HZ; DIN abrasion was performed in accordance with GB / T 9867–2008.

[0058] To further investigate the material properties, the compound rubber of Examples 1-2 and Comparative Examples 1-2 was pressed into tread semi-parts (including the crown, shoulder, and base) through a specific die. The tread semi-parts and other semi-finished parts (ply, belt, bead, airtight layer, sidewall rubber, etc.) were combined into a tire blank on a tire forming machine. The tire blank was placed in a vulcanizing machine and vulcanized at 173°C for 10 minutes to obtain the finished tire. The rolling resistance of the finished tire was tested according to GB / T 21910-2017, and the wet skid resistance of the finished tire was tested according to GB / T 29040-2012. The results are listed in Table 2.

[0059] Table 2. Material property test results obtained from Examples 1-2 and Comparative Examples 1-2

[0060] As can be seen from the data in Table 2, compared with Comparative Examples 1-2 (excluding rubber composite materials), Examples 1-2 have higher tan δ @ 0℃ values, lower tan δ @ 60℃ values, and higher wear resistance index by adding rubber composite materials. This indicates that rubber composite materials can effectively improve the wear resistance, wet slip resistance, and rolling resistance of the materials.

[0061] Tires made from the rubber material provided by this invention have excellent wet skid resistance and rolling resistance (the higher the wet skid resistance value, the better, and the lower the rolling resistance value, the better).

[0062] Although the above embodiments have provided a detailed description of the present invention, they are only some embodiments of the present invention, and not all embodiments. People can obtain other embodiments based on these embodiments without creative effort, and these embodiments all fall within the protection scope of the present invention.

Claims

1. A rubber composite material, characterized in that, It comprises silica and silane-modified liquid 1,4-polybutadiene grafted onto the surface of the silica; the specific surface area of ​​the silica is 3~50 m². 2 / g.

2. The rubber composite material according to claim 1, characterized in that, The particle size of the silica is 500~5000 mesh; The silane-modified liquid 1,4-polybutadiene has a silane grafting amount of 10-20%; the purity of the silane-modified liquid 1,4-polybutadiene is above 93%.

3. The method for preparing the rubber composite material according to claim 1 or 2, characterized in that, Includes the following steps: Rice husks are calcined to obtain a calcined product, which includes silicon dioxide. The calcined product and silane-modified liquid 1,4-polybutadiene were mixed and then subjected to a grafting reaction to obtain the rubber composite material.

4. The preparation method according to claim 3, characterized in that, The calcination temperature is 450~800℃, and the time is 1~3h.

5. The preparation method according to claim 3 or 4, characterized in that, The mass percentage of silicon dioxide in the calcined product is 60% or more.

6. The preparation method according to claim 3, characterized in that, The mass ratio of silica to silane-modified liquid 1,4-polybutadiene is 1:0.5~1.

5.

7. The preparation method according to claim 3 or 6, characterized in that, The grafting reaction is carried out at a temperature of 150~170℃ for a time of 0.5~2h, and the grafting reaction is carried out under a protective atmosphere.

8. The application of the rubber composite material according to claim 1 or 2 or the rubber composite material prepared by the preparation method according to any one of claims 3 to 7 as a processing aid for preparing compounded rubber.

9. A compound rubber, characterized in that, The following raw materials are included in the preparation in parts: 100-120 parts of rubber; 80-150 parts of silica; 5-10 parts of silane coupling agent; 1-3 parts stearic acid; 2-4 parts zinc oxide; Anti-aging agent 1-4 parts; Microcrystalline wax 1.5~2.5 parts; Processing aids: 10-30 parts; The processing aid is the rubber composite material according to claim 1 or 2, or the rubber composite material prepared by the preparation method according to any one of claims 3 to 7.

10. The use of the compound of claim 9 in the preparation of rubber tires.

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