A method for producing a butadiene-isoprene copolymer rubber masterbatch and a method for producing a vulcanized rubber

Abstract

The application provides a preparation method of butadiene-isoprene copolymer rubber masterbatch, which comprises the following steps: preparation of cis-butadiene-isoprene copolymer rubber glue solution; preparation of trans-butadiene-isoprene copolymer rubber glue solution; preparation of glue solution / filler or glue solution / filler / additive compound; and devolatilization to obtain butadiene-isoprene copolymer rubber masterbatch. The prepared masterbatch is mixed with accelerant and vulcanizing agent to obtain final masterbatch. The method provided by the application overcomes the problems of poor compatibility, co-vulcanization characteristics and filler dispersibility in the traditional butadiene rubber / isoprene rubber blending process; and the vulcanized rubber obtained after vulcanization has obvious advantages in mechanical strength, wear resistance, fatigue resistance, low rolling resistance and low heat generation.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of rubber composite material preparation, and particularly relates to a preparation method of butadiene-isoprene copolymer rubber masterbatch and a preparation method of vulcanized rubber. BACKGROUND

[0002] Cis-polybutadiene rubber (main component is butadiene rubber) has good wear resistance and fatigue resistance, and natural rubber (main component is isoprene rubber) has good mechanical strength. At present, the use amount of butadiene rubber in China is about 1.2 million tons / year, and the use amount of isoprene rubber is about 6 million tons / year. Butadiene rubber / isoprene rubber blend rubber is usually applied in the fields of tires, conveyor belts and rubber shock absorption, etc. However, due to the general compatibility and co-vulcanization characteristics of isoprene rubber and butadiene rubber, and poor filler dispersibility, etc., the application performance of the blend rubber is affected.

[0003] In addition to raw rubber, reinforcing agents, anti-aging agents, processing aids and vulcanizing agents, etc. are also needed in the rubber formula. The process of preparing the mixed rubber by using the traditional dry mixing process has high energy consumption, dust flying and easy to cause environmental pollution, and the filler and additive dispersibility of the prepared mixed rubber affects the application performance of the rubber products. SUMMARY

[0004] Therefore, the purpose of the present application is to provide a preparation method of butadiene-isoprene copolymer rubber masterbatch and a preparation method of vulcanized rubber. The vulcanized rubber prepared by the method has good mechanical properties, wear resistance, fatigue resistance, low rolling resistance and low heat generation performance.

[0005] The present application provides a preparation method of butadiene-isoprene copolymer rubber masterbatch, which comprises:

[0006] removing volatile components in the complex to obtain butadiene-isoprene copolymer rubber masterbatch;

[0007] The complex comprises butadiene-isoprene copolymer rubber solution and additives; the butadiene-isoprene copolymer rubber solution comprises one or both of cis-butadiene-isoprene copolymer rubber solution and trans-butadiene-isoprene copolymer rubber solution;

[0008] The additives are selected from fillers and / or additives.

[0009] Preferably, the preparation method of cis-butadiene-isoprene copolymer rubber solution comprises:

[0010] polymerizing butadiene and isoprene under the action of a catalyst to obtain cis-butadiene-isoprene copolymer rubber solution; or

[0011] Dissolving the cis-butadiene-isoprene copolymer rubber in a good solvent to obtain a cis-butadiene-isoprene copolymer rubber solution;

[0012] The catalyst comprises one or more of neodymium neodecanoate, triisobutyl aluminum and diethyl aluminum chloride.

[0013] Preferably, the preparation method of the trans-butadiene-isoprene copolymer rubber solution comprises:

[0014] Under the action of the catalyst, butadiene and isoprene are copolymerized to obtain a trans-butadiene-isoprene copolymer rubber solution; or

[0015] Dissolving the trans-butadiene-isoprene copolymer rubber in a good solvent to obtain a trans-butadiene-isoprene copolymer rubber solution;

[0016] The catalyst comprises one or more of titanium tetrachloride, magnesium chloride and triisobutyl aluminum.

[0017] Preferably, the copolymerization method is selected from solution polymerization or bulk polymerization.

[0018] Preferably, in the cis-butadiene-isoprene copolymer rubber solution, the cis-1,4-structure content of butadiene and isoprene is > 90 mol%; the molar ratio of butadiene and isoprene units is (5-95):(95-5); and the Mooney viscosity is 30-100.

[0019] Preferably, in the trans-butadiene-isoprene copolymer rubber solution, the trans-1,4-structure content of butadiene and isoprene is > 90 mol%; the molar ratio of butadiene and isoprene units is (5-70):(95-30); and the Mooney viscosity is 30-100.

[0020] Preferably, the filler is selected from one or more of carbon black, white carbon black, clay, calcium carbonate, graphene and carbon nanotubes.

[0021] Preferably, the additive is selected from one or more of an active agent, an antioxidant, a processing aid, a coupling agent, a flame retardant and a dye.

[0022] The application provides a preparation method of vulcanized rubber, comprising: using the butadiene-isoprene copolymer rubber masterbatch prepared by the method described in the above technical solution.

[0023] Preferably, the preparation method of the vulcanized rubber comprises:

[0024] Mixing the butadiene-isoprene copolymer rubber masterbatch, an accelerator and a vulcanizing agent to obtain a final masterbatch;

[0025] The final rubber compound is vulcanized to obtain a vulcanized rubber.

[0026] The application provides a novel masterbatch, solves the problems of poor compatibility and co-vulcanization characteristics of traditional butadiene / isoprene rubber blending, and realizes high dispersion of fillers or fillers and additives in the rubber matrix. The application solves the problems of poor compatibility and co-vulcanization characteristics in the traditional butadiene rubber / isoprene rubber blending process by using butadiene-isoprene copolymer rubber, and further solves the dispersion problem of fillers or fillers and additives in the rubber matrix by using a wet mixing process. The masterbatch prepared by the method of the application is mixed with accelerators and vulcanizing agents to obtain a final rubber compound, and the final rubber compound is further vulcanized to obtain a vulcanized rubber, which has very obvious advantages in mechanical properties, wear resistance, fatigue resistance, low rolling resistance and low heat generation. DETAILED DESCRIPTION

[0027] The technical solutions in the embodiments of the application will be clearly and completely described below. Obviously, the described embodiments are only part of the embodiments of the application, rather than all the embodiments. Based on the embodiments in the application, all other embodiments obtained by those skilled in the art without creative work fall within the protection scope of the application.

[0028] The application provides a preparation method of a butadiene-isoprene copolymer rubber masterbatch, comprising the following steps:

[0029] The volatile components in the compound are removed to obtain the butadiene-isoprene copolymer rubber masterbatch.

[0030] The compound comprises butadiene-isoprene copolymer rubber solution and an auxiliary agent; the butadiene-isoprene copolymer rubber solution comprises one or both of cis-butadiene-isoprene copolymer rubber solution and trans-butadiene-isoprene copolymer rubber solution.

[0031] The auxiliary agent is selected from fillers and / or additives.

[0032] In the application, the content of cis-1,4-structure of butadiene and isoprene in the cis-butadiene-isoprene copolymer rubber solution is preferably > 90 mol%, more preferably > 95 mol%; the molar ratio of butadiene and isoprene units is preferably (5-95):(95-5), more preferably (5-30):(95-70) and (50-95):(50-5), more preferably (5-20):(80-95) and (95-80):(20-5); the Mooney viscosity is preferably 30-100, more preferably 40-90, more preferably 50-80, and most preferably 60-70.

[0033] In the present application, the preparation method of the cis-butadiene-isoprene copolymer rubber solution comprises the following steps:

[0034] Under the action of a catalyst, butadiene and isoprene are copolymerized to obtain a cis-butadiene-isoprene copolymer rubber solution; the catalyst comprises one or more of neodymium neodecanoate, triisobutyl aluminum and diethyl aluminum chloride.

[0035] In the present application, the molar ratio of butadiene to isoprene is preferably (1-99):(99:1), more preferably (3-30):(97-70) or (40-95):(60-5), and most preferably (4-16):(96-84) or (80-95):(20-5).

[0036] In the present application, the molar ratio of neodymium neodecanoate to monomers (total molar amount of isoprene monomers and butadiene monomers) is preferably 1-7×10 -4 :1, more preferably 3-5×10 -4 :1, and most preferably 3.5×10 -4 :1; the molar ratio of triisobutyl aluminum to monomers (total molar amount of isoprene monomers and butadiene monomers) is preferably 1-10×10 -3 :1, more preferably 4-8×10 -3 :1, and most preferably 6×10 -3 :1.

[0037] In the present application, the copolymerization method is preferably selected from solution polymerization or bulk polymerization; the copolymerization temperature is preferably 20-60℃, more preferably 35-55℃, and most preferably 45-50℃; the copolymerization time is preferably 0.5-6h, more preferably 1-5h, and most preferably 3h.

[0038] In the present application, the preparation method of the cis-butadiene-isoprene copolymer rubber solution preferably comprises the following steps:

[0039] The cis-butadiene-isoprene copolymer rubber is dissolved in a good solvent to obtain a cis-butadiene-isoprene copolymer rubber solution.

[0040] In the present application, the good solvent is preferably selected from one or more of heptane, toluene, tetrahydrofuran.

[0041] In the present application, the mass ratio of the cis-butadiene-isoprene copolymer rubber to the good solvent is preferably (10-30):100, more preferably (15-25):100, and most preferably 20:100.

[0042] In the present application, the dissolving temperature is preferably 30-60℃, more preferably 45-60℃, and most preferably 55℃.

[0043] In the present application, the trans-butadiene-isoprene copolymer rubber solution has a trans-1,4-structure content of butadiene and isoprene of preferably >90 mol%, more preferably >95 mol%, and a molar ratio of butadiene to isoprene units of preferably (5-70):(95-30), more preferably (5-50):(95-50), and most preferably (5-30):(95-70); and a Mooney viscosity of preferably 30-100, more preferably 40-90, more preferably 50-80, and most preferably 60-70.

[0044] In the present application, the preparation method of the trans-butadiene-isoprene copolymer rubber solution preferably comprises:

[0045] under the action of a catalyst, butadiene and isoprene are copolymerized to obtain a trans-butadiene-isoprene copolymer rubber solution; the catalyst comprises one or more of titanium tetrachloride, magnesium chloride and triisobutyl aluminum.

[0046] In the present application, the molar ratio of butadiene to isoprene is preferably (1-20):(99-80), more preferably (1-10):(99-90), and most preferably (1-5):(99-95).

[0047] In the present application, the molar ratio of titanium tetrachloride to monomers (total molar amount of butadiene monomers and isoprene monomers) is preferably 1-10×10 -5 :1, more preferably 3-8×10 -5 :1, and most preferably 5×10 -5 :1; and the molar ratio of triisobutyl aluminum to monomers (total molar amount of butadiene monomers and isoprene monomers) is preferably 1-10×10 -4 :1, more preferably 3-8×10 -4 :1, and most preferably 4×10 -4 :1.

[0048] In the present application, the copolymerization method is preferably selected from solution polymerization or bulk polymerization; the copolymerization temperature is preferably 20-60°C, more preferably 35-55°C, and most preferably 45-50°C; and the copolymerization time is preferably 0.5-6h, more preferably 1-5h, and most preferably 3h.

[0049] In the present application, the preparation method of the trans-butadiene-isoprene copolymer rubber solution preferably comprises:

[0050] trans-butadiene-isoprene copolymer rubber is dissolved in a good solvent to obtain a trans-butadiene-isoprene copolymer rubber solution.

[0051] In the present application, the good solvent is preferably selected from one or more of heptane, toluene, tetrahydrofuran.

[0052] In the present application, the mass ratio of the trans-butadiene-isoprene copolymer rubber and the good solvent is preferably (10-30):100, more preferably (15-25):100, and most preferably 20:100.

[0053] In the present application, the temperature for dissolving is preferably 30-60°C, more preferably 45-60°C, and most preferably 55°C.

[0054] In the present application, the filler is preferably selected from one or more of carbon black, white carbon black, clay, calcium carbonate, graphene, and carbon nanotube.

[0055] In the present application, the additive is preferably selected from one or more of an active agent, an antioxidant, a processing aid, a coupling agent, a flame retardant, and a dye, and more preferably from an active agent, an antioxidant, and a processing aid.

[0056] In the present application, the active agent is preferably selected from zinc oxide and stearic acid.

[0057] In the present application, the antioxidant is preferably selected from antioxidant 4020 and antioxidant RD.

[0058] In the present application, the processing aid is preferably selected from one or more of aromatic hydrocarbon oil and paraffin oil.

[0059] In the present application, the coupling agent is preferably selected from a silane coupling agent and / or a phthalate coupling agent.

[0060] The present application does not have any limitation on the mass ratio of the cis-butadiene-isoprene copolymer rubber solution and the trans-butadiene-isoprene copolymer rubber solution, which can be mixed in any ratio, preferably (95-80):(5-20), and more preferably (90-85):(10-15).

[0061] In the present application, the mass ratio of the total dry rubber, filler, active agent, antioxidant, and processing aid in the cis-butadiene-isoprene copolymer rubber solution and the trans-butadiene-isoprene copolymer rubber solution is preferably 100:(0-120):(0-15):(0.5-15):(0-20), more preferably 100:(10-100):(1-12):(1-12):(1-15), more preferably 100:(20-80):(2-10):(2-10):(2-12), more preferably 100:(40-70):(3-8):(5-8):(5-10), and most preferably 100:(50-60):(4-7):(6-7):(6-8).

[0062] In the present application, the preparation method of the compound preferably comprises:

[0063] The cis-butadiene-isoprene copolymer rubber glue solution, the trans-butadiene-isoprene copolymer rubber glue solution and the auxiliary agent are mixed to obtain the compound; the mixing is realized by stirring to achieve uniform dispersion; the mixing is preferably carried out under stirring; the stirring speed is preferably 600-1000 rpm, more preferably 700-900 rpm, and most preferably 800 rpm; the stirring time is preferably 0.5-1.5 h, more preferably 1 h; and the mixing temperature is preferably 50-60℃, more preferably 55℃.

[0064] In the present application, the preparation method of the compound preferably comprises:

[0065] The cis-butadiene-isoprene copolymer rubber glue solution and the auxiliary agent are mixed to obtain the first compound;

[0066] The trans-butadiene-isoprene copolymer rubber glue solution and the auxiliary agent are mixed to obtain the second compound;

[0067] The first compound and the second compound are mixed to obtain the compound.

[0068] In the present application, the mixing is preferably stirring mixing; the stirring speed is preferably 600-1000 rpm, more preferably 700-900 rpm, and most preferably 800 rpm; the stirring time is preferably 0.5-1.5 h, more preferably 1 h; and the mixing temperature is preferably 50-60℃, more preferably 55℃.

[0069] In the present application, the auxiliary agent preferably further comprises a solvent. In the mixing process, the auxiliary agent can be directly added to the rubber glue solution, or the components in the auxiliary agent can be configured into a suspension and added; the solvent is preferably one or more of heptane, heptane, toluene, and tetrahydrofuran.

[0070] In the present application, the method for removing volatile components from the compound is preferably drying the compound to a constant weight; the drying is preferably carried out in a vacuum oven; and the drying temperature is preferably 50-70℃, more preferably 55-65℃, and most preferably 60℃.

[0071] The present application provides a vulcanized rubber preparation method, comprising: using the butadiene-isoprene copolymer rubber masterbatch material prepared by the method described in the above technical solution.

[0072] In the present application, the preparation method of the vulcanized rubber preferably comprises:

[0073] Mixing butadiene-isoprene copolymer rubber masterbatch, accelerator and vulcanizing agent to obtain final rubber;

[0074] Vulcanizing the final rubber to obtain vulcanized rubber.

[0075] In the present application, the butadiene-isoprene copolymer rubber masterbatch is prepared by the method described in the above technical solution; the accelerator is preferably selected from accelerator NS, and the vulcanizing agent is preferably selected from sulfur.

[0076] In the present application, the mass ratio of the butadiene-isoprene copolymer rubber, the accelerator and the vulcanizing agent is preferably 100:(1-3):(1-2), more preferably 100:2:1.5; the temperature of the mixing is preferably 100-110℃, more preferably 105℃; the time of the mixing is preferably 80-120 seconds, more preferably 90-110 seconds, and most preferably 100 seconds.

[0077] In the present application, the temperature of the vulcanization is preferably 130-170℃, more preferably 140-160℃, and most preferably 150℃; the time of the vulcanization is preferably 20-40min, more preferably 25-35min, and most preferably 30min.

[0078] The final rubber is obtained by mixing the masterbatch prepared by the method provided in the present application with accelerator, vulcanizing agent and scorch retarder, and the vulcanized rubber is obtained by high-temperature vulcanization of the final rubber; this process overcomes the problems of poor compatibility, co-vulcanization characteristics and filler dispersion in the traditional butadiene rubber / isoprene rubber blending process, and the vulcanized rubber has obvious advantages in mechanical strength, wear resistance, fatigue performance, rolling resistance and heat generation performance. In the present application, the wet mixing of butadiene-isoprene copolymer rubber with relatively low butadiene content and relatively high Mooney viscosity, fillers and rubber additives has outstanding advantages in mechanical strength, wear resistance, rolling resistance and heat generation performance; the wet mixing of butadiene-isoprene copolymer rubber with relatively high butadiene content and moderate Mooney viscosity, fillers and rubber additives has outstanding advantages in fatigue performance.

[0079] Dry mixing technology of comparative example 1

[0080] 80 parts of natural rubber (product of SCR WF type provided by Hainan Natural Rubber Industry Group Co., Ltd.), 20 parts of butadiene rubber (product of BR 9000 type provided by Qilu Petrochemical Company), 5 parts of active agent (3 parts of zinc oxide, 2 parts of stearic acid), 4 parts of antioxidant (2 parts of antioxidant 4020, 1 part of antioxidant RD, 1 part of paraffin wax), 60 parts of white carbon black, and 6 parts of silane coupling agent are mixed for 4 minutes by using a mixer, and a first-stage mixing rubber is obtained at a discharge temperature of 158 ℃. Then, the first-stage mixing rubber, 2 parts of accelerator NS, and 1.6 parts of sulfur are mixed for 100 seconds, and a final mixing rubber is obtained at a discharge temperature of 105 ℃. The final mixing rubber is vulcanized at 150 ℃ for 30 min to obtain a vulcanized rubber.

[0081] Example 1

[0082] Step 1: Preparation of cis-butadiene-isoprene copolymer rubber solution, solution polymerization process, monomer: n-hexane = 1:4 (mass ratio), neodymium neodecanoate and (total moles of butadiene monomer and isoprene monomer) molar ratio is 3.5 x 10 -4 : 1, the molar ratio of triisobutylaluminum and monomers (total moles of butadiene monomer and isoprene monomer) is 6 x 10 -3 : 1, the molar ratio of butadiene to isoprene is 16:84, and the polymerization is carried out at 50 ℃ for 2 h to obtain a cis-butadiene-isoprene copolymer rubber solution with a conversion rate of 80%.

[0083] Part of the solution is precipitated in ethanol to obtain cis-butadiene-isoprene copolymer rubber, and after drying, the cis-1,4-structure content (characterized by nuclear magnetic hydrogen spectrum) is 96 mol%, the molar ratio of butadiene to isoprene structural units (characterized by nuclear magnetic hydrogen spectrum) is 20:80, and the Mooney viscosity (tested according to GB 1232 standard) is 85.

[0084] Step 2: Preparation of trans-butadiene-isoprene copolymer rubber solution, bulk polymerization process, titanium tetrachloride: monomer (total moles of butadiene monomer and isoprene monomer) molar ratio is 5 x 10 -5 : 1, the molar ratio of butadiene to isoprene is 1:99, the hydrogen partial pressure is 0.1 MPa, and the polymerization is carried out at 40 ℃ for 2 h to obtain a trans-butadiene-isoprene copolymer rubber solution with a conversion rate of 20%.

[0085] Part of the solution is precipitated in ethanol to obtain trans-butadiene-isoprene copolymer rubber, and after drying, the trans-1,4-structure content is 94 mol%, the molar ratio of butadiene to isoprene structural units is 5:95, and the Mooney viscosity is 58.

[0086] Step 3: The rubber solution containing 70 parts of cis-butadiene-isoprene copolymer rubber dry gum (part of the rubber solution was taken out to remove unreacted monomers by drying) was mixed with the rubber solution containing 30 parts of trans-butadiene-isoprene copolymer rubber dry gum, 5 parts of activator (3 parts of zinc oxide, 2 parts of stearic acid), 4 parts of antioxidant (2 parts of antioxidant 4020, 1 part of antioxidant RD, 1 part of paraffin wax), 60 parts of white carbon black, and 6 parts of silane coupling agent. The mixture was stirred in a stirrer at 55°C at a speed of 800 rpm for 1 h to obtain a rubber solution / filler / auxiliary compound.

[0087] Step 4: The rubber solution / filler / auxiliary compound was placed in a vacuum oven and dried to constant weight (60°C) to obtain a butadiene-isoprene copolymer rubber master batch.

[0088] Step 5: The butadiene-isoprene copolymer rubber master batch, 2 parts of accelerator NS, and 1.6 parts of sulfur were mixed by mixing for 100 seconds at a discharge temperature of 103°C to obtain a final rubber compound. The final rubber compound was vulcanized at 150°C for 30 min to obtain a vulcanized rubber.

[0089] Example 2

[0090] Step 1: Preparation of a cis-butadiene-isoprene copolymer rubber solution, with a butadiene to isoprene molar ratio of 4:96. The other preparation methods and process conditions were the same as those in step 1 of Example 1.

[0091] Part of the rubber solution was precipitated in ethanol to obtain cis-butadiene-isoprene copolymer rubber. After drying, the cis-1,4-structure content was 95 mol%, the butadiene to isoprene structure unit molar ratio was 5:95, and the Mooney viscosity was 80.

[0092] Step 2: 60 parts of white carbon black and 6 parts of silane coupling agent were mixed with 600 ml of n-heptane to form a suspension. The cis-butadiene-isoprene copolymer rubber solution was mixed with the filler and auxiliary suspension in a stirrer at 55°C at a speed of 800 rpm for 1 h to obtain a rubber solution / filler compound.

[0093] Step 3: The rubber solution / filler compound was placed in a vacuum oven and dried to constant weight (60°C) to obtain a butadiene-isoprene copolymer rubber master batch.

[0094] Step 4: The butadiene-isoprene copolymer rubber master batch was mixed with 5 parts of activator (3 parts of zinc oxide, 2 parts of stearic acid) and 4 parts of antioxidant (2 parts of antioxidant 4020, 1 part of antioxidant RD, 1 part of paraffin wax) using an internal mixer for 3 min at a discharge temperature of 145°C to obtain a mixture.

[0095] Step 5: The mixture in step 4 was mixed with 2 parts of accelerator NS, 1.6 parts of sulfur, mixing time 100 seconds, discharge temperature 110°C, to obtain the final mixing rubber, and the final mixing rubber was vulcanized at 150°C for 30 min to obtain the vulcanized rubber.

[0096] Example 3

[0097] Step 1: Preparation of the trans-butadiene-isoprene copolymer rubber solution, 100 parts of trans-butadiene-isoprene copolymer rubber was dissolved in 1000 ml of n-heptane to obtain a rubber solution.

[0098] The trans-butadiene-isoprene copolymer rubber used was selected from TBIR1059 of Shandong Huaguo High Polymer Material Co., Ltd., with a trans-1,4 structure content of 98 mol%, a butadiene to isoprene structure unit molar ratio of 10:90, and a Mooney viscosity of 60.

[0099] Step 2: The solution containing 100 parts of trans-butadiene-isoprene copolymer rubber was mixed with 5 parts of active agent (3 parts of zinc oxide, 2 parts of stearic acid), 4 parts of antioxidant (2 parts of antioxidant 4020, 1 part of antioxidant RD, 1 part of paraffin wax), 60 parts of white carbon black, and 6 parts of silane coupling agent in a stirrer at 55°C with a stirring speed of 800 rpm for 1 h to obtain a rubber solution / filler / auxiliary compound.

[0100] Step 3: The rubber solution / filler / auxiliary compound was placed in a vacuum oven and dried to constant weight (60°C) to obtain a butadiene-isoprene copolymer rubber masterbatch.

[0101] Step 4: The butadiene-isoprene copolymer rubber masterbatch, 2 parts of accelerator NS, and 1.6 parts of sulfur were mixed, the mixing time was 100 seconds, and the discharge temperature was 108°C to obtain the final mixing rubber, and the final mixing rubber was vulcanized at 150°C for 30 min to obtain the vulcanized rubber.

[0102] Comparative Example 2 Dry Mixing Technology

[0103] Mixing 30 parts of natural rubber (product of SCR WF type provided by Hainan Natural Rubber Industry Group Co., Ltd.), 70 parts of butadiene rubber (product of BR 9000 type provided by Qilu Petrochemical Company), 55 parts of carbon black, 6 parts of activator (4 parts of zinc oxide, 2 parts of stearic acid), 15 parts of antioxidant (4 parts of antioxidant 4020, 2.5 parts of antioxidant RD, 3.5 parts of antioxidant 3100, 5 parts of paraffin), 15 parts of processing aid (7 parts of naphthenic oil, 4 parts of C5 resin, 4 parts of carbon black dispersant) by using an internal mixer, mixing time 5 min, discharge temperature 145℃, to obtain a first-stage rubber compound, then mixing the first-stage rubber compound, 1.1 parts of accelerator CBS, 2.0 parts of sulfur, 0.3 parts of anti-scorching agent CTP, mixing time 100 seconds, discharge temperature 103℃, to obtain a final rubber compound; vulcanizing the final rubber compound at 150℃ for 30 min to obtain a vulcanized rubber.

[0104] Example 4

[0105] Step 1: Preparation of cis-butadiene-isoprene copolymer rubber solution, the molar ratio of butadiene to isoprene is 92:8, and other preparation methods and process conditions are the same as those in step 1 of Example 1.

[0106] Part of the solution is precipitated in ethanol to obtain cis-butadiene-isoprene copolymer rubber, and after drying, the content of cis-1,4-structure is tested to be 94 mol%, the molar ratio of butadiene to isoprene structural unit is 95:5, and the Mooney viscosity is 62.

[0107] Step 2: Preparation of trans-butadiene-isoprene copolymer rubber solution, the molar ratio of butadiene to isoprene is 15:85, and other preparation methods and process conditions are the same as those in step 2 of Example 1.

[0108] Part of the solution is precipitated in ethanol to obtain trans-butadiene-isoprene copolymer rubber, and after drying, the content of trans-1,4-structure is tested to be 96 mol%, the molar ratio of butadiene to isoprene structural unit is 70:30, and the Mooney viscosity is 58.

[0109] Step 3:

[0110] (1) Mixing 100 parts of cis-butadiene-isoprene copolymer rubber solution, 55 parts of carbon black, 6 parts of activator (4 parts of zinc oxide, 2 parts of stearic acid), 15 parts of antioxidant (4 parts of antioxidant 4020, 2.5 parts of antioxidant RD, 3.5 parts of antioxidant 3100, 5 parts of paraffin), 15 parts of processing aid (7 parts of naphthenic oil, 4 parts of C5 resin, 4 parts of carbon black dispersant) in a stirrer at 55℃ with a stirring speed of 800 r / min for 1 h to obtain a composite 1.

[0111] (2) A rubber solution containing 100 parts of trans-butadiene-isoprene copolymer rubber was mixed with 55 parts of carbon black, 6 parts of activator (4 parts of zinc oxide, 2 parts of stearic acid), 15 parts of antioxidant (4 parts of antioxidant 4020, 2.5 parts of antioxidant RD, 3.5 parts of antioxidant 3100, 5 parts of paraffin wax), 15 parts of processing aid (7 parts of naphthenic oil, 4 parts of C5 resin, 4 parts of carbon black dispersant) in a stirrer at 55°C at a speed of 800 rpm for 1 h to obtain a compound 2.

[0112] (3) A rubber solution / filler / additive compound obtained by mixing the compound 1 and the compound 2 at a ratio of 70:30.

[0113] Step 4: The rubber solution / filler / additive compound was placed in a vacuum oven to dry to constant weight (drying temperature 60°C) to obtain a butadiene-isoprene copolymer rubber master batch.

[0114] Step 5: The butadiene-isoprene copolymer rubber master batch, 1.1 parts of accelerator CBS, 2.0 parts of sulfur, and 0.3 parts of anti-scorching agent CTP were mixed for 100 seconds, and the discharge temperature was 100°C to obtain a final compound; the final compound was vulcanized at 150°C for 30 min to obtain a vulcanized rubber.

[0115] Example 5

[0116] Step 1: Preparation of a trans-butadiene-isoprene copolymer rubber solution, 100 parts of trans-butadiene-isoprene copolymer rubber was dissolved in 1000 ml of n-heptane to obtain a rubber solution.

[0117] The trans-butadiene-isoprene copolymer rubber used was selected from TBIR2249 of Shandong Huaguo High Polymer Material Co., Ltd., the content of trans-1,4 structure was 96 mol%, the molar ratio of butadiene to isoprene structural units was 22:78, and the Mooney viscosity was 49.

[0118] Step 2: The solution containing 100 parts of trans-butadiene-isoprene copolymer rubber was mixed with 55 parts of carbon black, 6 parts of activator (4 parts of zinc oxide, 2 parts of stearic acid), 15 parts of antioxidant (4 parts of antioxidant 4020, 2.5 parts of antioxidant RD, 3.5 parts of antioxidant 3100, 5 parts of paraffin wax), 15 parts of processing aid (7 parts of naphthenic oil, 4 parts of C5 resin, 4 parts of carbon black dispersant) in a stirrer (55°C) at a speed of 800 rpm for 1 h to obtain a rubber solution / filler / additive compound.

[0119] Step 3: The rubber solution / filler / additive compound was placed in a vacuum oven to dry to constant weight (drying temperature 60°C) to obtain a butadiene-isoprene copolymer rubber master batch.

[0120] Step 4: mixing butadiene-isoprene copolymer rubber masterbatch, 2 parts of accelerator NS, 1.6 parts of sulfur, mixing time 100 seconds, discharge temperature 102℃, to obtain a final rubber; vulcanizing the final rubber at 150℃ for 30 minutes to obtain a vulcanized rubber.

[0121] Performance detection

[0122] The vulcanized rubber prepared by the inventive examples and the comparative examples was subjected to performance detection, and the detection method is shown in Table 1:

[0123] Table 1 Performance detection method of vulcanized rubber

[0124] Performance Apparatus used Standard or method used Filler dispersion GT-505-CBD (Gotech) / Tensile strength Zwick electronic tensile tester (Zwick) GB / T 528-2009 Tear performance Zwick electronic tensile tester (Zwick) GB / T 529-2008 Compression heat build-up RH-2000 compression heat build-up tester (Gotech) Temperature 55℃, load 1 MPa Rebound performance Impact resilience tester (Gotech) GB / T 1681-2009 DIN abrasion GT-7012-D Shore abrasion tester (Gotech) GB / T 9867-2008 Tan delta @ 60℃ 861 e dynamic mechanical properties analyzer (mettler)]]> Frequency 10 Hz, strain 5% Fatigue performance FT 3000 Demattia fatigue tester (MonTech) GB / T 13934-2006

[0125] The performance detection results of the vulcanized rubber prepared by Examples 1-3 and Comparative Example 1 are shown in Table 2:

[0126] Table 2 Performance test results of vulcanized rubber prepared by Examples 1-3 and Comparative Example 1

[0127] Comparative Example 1 Example 1 Example 2 Example 3 Compound filler dispersion rating 6.2 8.8 8.3 8.5 Tensile strength, MPa 23.8 25.9 25.2 25.2 100% modulus, MPa 2.9 2.3 2.2 3.6 300% modulus, MPa 12.9 15.0 14.7 14.9 Elongation at break, % 580 539 510 525 Tear strength, KN / m 88 107 95 99 Rebound, % 60 67 67 68 Compression heat build-up, ℃ 23.1 17.6 18.0 18.3 Tan delta @ 60℃ 0.167 0.096 0.102 0.105 DIN abrasion, mm 3 / 40m]]> 89 67 72 32

[0128] As shown in Table 2, compared with the traditional dry mixing process (Comparative Example 1), the filler dispersion grade of the natural rubber / butadiene rubber blend product prepared by the inventive examples is significantly improved; the tensile strength of the vulcanized wet masterbatch prepared by the inventive method is improved by 1.4-2.1 MPa, the tear strength is improved by 7-19 KN / m, the rebound performance is improved by 7 units, the compression heat generation is reduced by 5.1-5.5℃, the tanδ@60℃ representing the rolling resistance is reduced by about 45%, and the abrasion volume is reduced by 19%-64%. It is obvious that the filler dispersion and application performance of the wet masterbatch prepared by the inventive method are very excellent, and can be applied in the field of tire tread rubber with high mechanical strength, good wear resistance, low rolling resistance and heat generation.

[0129] The performance detection results of the vulcanized rubber prepared by Examples 4-5 and Comparative Example 2 are shown in Table 3:

[0130] Table 3 Performance test results of vulcanized rubber prepared by Examples 4-5 and Comparative Example 2

[0131] Comparative Example 2 Example 4 Example 5 Compound filler dispersion rating 6.9 9.2 8.9 Tensile strength, MPa 14.8 16.9 16.2 100% modulus, MPa 1.5 1.2 1.4 300% modulus, MPa 8.7 9.3 9.0 Elongation at break, % 556 520 539 Primary flex fatigue life, million times 280 ＞500 ＞500

[0132] As shown in Table 3, compared with the natural rubber / butadiene rubber blend product prepared by the traditional dry rubber mixing process (Comparative Example 2), the filler dispersion grade of Examples 4-5 is significantly improved; the tensile strength and primary flex fatigue life of the vulcanized product prepared from the wet masterbatch prepared by the method of the present application are significantly improved. It is obvious that the filler dispersion and application performance of the wet masterbatch prepared by the method of the present application are very excellent, and can be applied in the field of shock-absorbing products with high mechanical strength and good fatigue resistance.

[0133] While the application has been described and illustrated with reference to specific embodiments thereof, those skilled in the art will appreciate that various adaptations, changes, modifications, substitutions, deletions, or the like can be made by those skilled in the art without departing from the spirit and scope of the application as defined in the following claims. It is intended that all such modifications or alterations be included within this application's scope. Although the method disclosed herein has been described with reference to particular operations performed in a particular order, it will be understood that these operations can be combined, sub-divided, or re-ordered to form equivalent methods without departing from the teachings of the present application. Accordingly, unless specifically indicated herein, the order and grouping of operations are not a limitation of this application.

Claims

1.A method for preparing a vulcanized rubber, comprising the following steps: Step 1: preparation of cis-butadiene-isoprene copolymer rubber solution, solution polymerization process, monomer: mass ratio of n-hexane 1:4, molar ratio of neodymium neodecanoate to total moles of butadiene monomer and isoprene monomer 3.5 x 10 -4 : 1, molar ratio of triisobutylaluminum to total moles of butadiene monomer and isoprene monomer 6 x 10 -3 : 1, butadiene to isoprene feed molar ratio 16:84, polymerization at 50°C for 2h, cis-butadiene-isoprene copolymer rubber solution with 80% conversion rate was obtained; cis-butadiene-isoprene copolymer rubber is precipitated from part of the rubber solution in ethanol, and after drying, the cis-1,4-structure content is 96 mol%, the molar ratio of butadiene to isoprene structural units is 20:80, and the Mooney viscosity is 85, wherein the cis-1,4-structure content and the molar ratio of butadiene to isoprene structural units are characterized by nuclear magnetic hydrogen spectrum, and the Mooney viscosity is tested according to GB1232 standard; Step 2: Preparation of trans-butadiene-isoprene copolymer rubber solution, bulk polymerization process, molar ratio of titanium tetrachloride to total butadiene monomer and isoprene monomer was 5 x 10 -5 : 1, molar ratio of butadiene to isoprene was 1:99, hydrogen partial pressure was 0.1 MPa, and polymerization was carried out at 40°C for 2h to obtain a trans-butadiene-isoprene copolymer rubber solution with a conversion rate of 20%; trans-butadiene-isoprene copolymer rubber is precipitated from part of the rubber solution in ethanol, and after drying, the trans-1,4-structure content is 94 mol%, the molar ratio of butadiene to isoprene structural units is 5:95, and the Mooney viscosity is 58; Step 3: the rubber solution containing 70 parts of cis-butadiene-isoprene copolymer dry rubber is mixed with the rubber solution containing 30 parts of trans-butadiene-isoprene copolymer dry rubber, 5 parts of active agent, 4 parts of antioxidant, 60 parts of white carbon black, and 6 parts of silane coupling agent are added, and the mixture is stirred in a stirrer at 55°C at a speed of 800 revolutions / min for 1h to obtain a rubber solution / filler / auxiliary compound, wherein the active agent consists of 3 parts of zinc oxide and 2 parts of stearic acid, and the antioxidant consists of 2 parts of antioxidant 4020, 1 part of antioxidant RD, and 1 part of paraffin wax; Step 4: the rubber solution / filler / auxiliary compound is placed in a vacuum oven and dried at 60°C to constant weight to obtain butadiene-isoprene copolymer masterbatch; Step 5: the butadiene-isoprene copolymer masterbatch, 2 parts of accelerator NS, and 1.6 parts of sulfur are mixed, the mixing time is 100 seconds, and the discharge temperature is 103°C to obtain a final rubber compound, and the final rubber compound is vulcanized at 150°C for 30 min to obtain a vulcanized rubber.