Preparation method of plasticizing cobalt salt for rubber

Abstract

The invention discloses a preparation method of plasticized cobalt salt for rubber, and belongs to the technical field of cobalt salt preparation, the preparation method comprises the following steps: S1, raw material preparation: 20 parts of cobalt hydroxide, 26 parts of isocaprylic acid, 7 parts of stearic acid, 2 parts of oleic acid, 16 parts of propionic acid, 20 parts of n-butyl propionate and 16.5 parts of tributyl borate; s2, pretreatment of raw materials: cobalt hydroxide: sieving with a 200-mesh sieve to remove caking, and after sieving is completed, drying in a vacuum drying oven at 80 DEG C for 4 hours to ensure that the moisture content is less than or equal to 0.5%; the application range of rubber plasticization is wide, including but not limited to improvement of the temperature stability of rubber, improvement of the plasticization of rubber, reduction of the viscosity of rubber, endowing of rubber with flame retardance and inhibition of oxygen permeability, and meanwhile, rubber products can adapt to different application requirements such as automobile parts, electric wires and cables, sealing materials and the like.

Description

Technical Field

[0001] The invention belongs to the technical field of cobalt salt preparation, and in particular relates to a method for preparing plasticizing cobalt salt for rubber. Background Art

[0002] The primary function of rubber plasticizers is to increase the plasticity and fluidity of rubber, improve the processing properties of rubber products, and enhance the physical and mechanical properties of rubber products. As an essential component in rubber mixing, cobalt salt additives are in high demand in the rubber industry, particularly the tire industry. However, when using traditional rubber plasticizers, it is important to be mindful of the potential release of harmful substances that could impact the environment and human health. Traditional plasticizers may contain hazardous chemicals, such as benzene and neodymium, which can pollute the atmosphere, soil, and water, and pose potential risks to human health.

[0003] Traditional cobalt salts, with their excellent adhesion-promoting properties, are irreplaceable in rubbers formulated with metal skeletons. However, cobalt ions also significantly affect the hardness and plasticity of the rubber after vulcanization. This complicates the formulation of rubbers that require both a metal skeleton and a certain degree of plasticity, necessitating the addition of additional plasticizers to meet the ultimate requirements. To address this, we propose a method for preparing plasticizing cobalt salts for rubber. Summary of the Invention

[0004] The present invention provides a method for preparing a plasticizing cobalt salt for rubber, so as to solve the problems raised in the above background technology.

[0005] To achieve the above object, the present invention provides the following technical solution: a method for preparing a plasticizing cobalt salt for rubber, comprising the following steps:

[0006] S1. Raw material preparation: 20 to 30 parts of cobalt hydroxide, 15 to 26 parts of isooctanoic acid, 7 to 10 parts of stearic acid, 2 to 5 parts of oleic acid, 10 to 16 parts of propionic acid, 20 to 30 parts of n-butyl propionate, and 10 to 16.5 parts of tributyl borate;

[0007] S2. Raw material pretreatment:

[0008] Cobalt hydroxide: sieve through a 200-mesh sieve to remove lumps. After sieving, dry in a vacuum drying oven at 80°C for 4 hours to ensure that the moisture content is ≤0.5%;

[0009] Isooctanoic acid, stearic acid, oleic acid, and propionic acid: Purify by vacuum distillation at a pressure of -0.09 MPa, with temperatures controlled at 120°C, 225°C, 180°C, and 140°C, respectively, and an acid value controlled at 180 mgKOH / g to 200 mgKOH / g;

[0010] Butyl propionate was sieved with 3A molecular sieve and then dehydrated for 4 hours, with a water content of ≤100ppm;

[0011] Tributyl borate requires: nitrogen bubbling, deoxygenation for 30 minutes, flow rate of 0.5L / min;

[0012] S3, adding n-butyl propionate as a solvent to the reactor, preheating n-butyl propionate to 50° C., and adding it to the reactor;

[0013] S4. Add cobalt hydroxide and stir to form a pink suspension. Stir at 300 rpm. Slowly add cobalt hydroxide and continue stirring for 30 min until a uniform pink suspension is obtained.

[0014] S5. Raise the temperature to 90°C to 100°C and start the reflux device;

[0015] S6. Add 2-ethylhexanoic acid, stearic acid, oleic acid, and propionic acid dropwise in sequence, controlling the addition rate to avoid local overheating.

[0016] S7, reflux reaction for 2h to ensure sufficient salt formation;

[0017] S8. Raise the temperature to 175°C to 185°C, distill at a vacuum pressure of ≤-0.085 MPa for 1.5 hours, and stir at 150 rpm to remove wastewater and residual solvent;

[0018] S9, adding tributyl borate, and keeping the temperature at 160°C to 170°C for 2 hours. During the reaction, adding an organotin catalyst accounting for 0.1% to 0.5% of the total material;

[0019] S10, heating to 175°C to 185°C, and distilling at a negative pressure of ≤-0.085 MPa for 2 hours to remove the by-product n-butyl propionate;

[0020] S11, discharge the cooled blue solid.

[0021] Furthermore, in step S2, after the cobalt hydroxide is sieved and dried, a laser particle size analyzer is used to detect its particle size distribution to ensure that the particle size is between 1 μm and 10 μm, and the proportion of particles within the appropriate range reaches 90%;

[0022] The condensation temperature of isooctanoic acid, stearic acid, oleic acid and propionic acid can be set to 50℃~60℃, and the acid value can be tested by automatic potentiometric titrator;

[0023] Before using 3A molecular sieve to screen n-butyl propionate, the 3A molecular sieve is first activated at 300° C. for 4 to 6 hours.

[0024] Furthermore, in step S3, a glass-lined reactor is used, and nitrogen is introduced throughout the entire process;

[0025] n-Butyl propionate was slowly and evenly added to the reactor using a peristaltic pump, with the addition rate set at 8 ml / min to 10 ml / min.

[0026] Furthermore, in step S4, during the process of slowly adding cobalt hydroxide, it is necessary to check the color change and uniformity of the suspension in the reactor through an observation window.

[0027] Furthermore, in step S5, the heating rate is 2°C / min, the temperature is raised to 95°C, and the condensing water is turned on, the flow rate of the condensing water is 10L / min, and a spherical condenser is used as a reflux device.

[0028] Furthermore, in step S6, the isooctanoic acid: the temperature is controlled at a constant temperature of 90° C. to 95° C., the dropping speed is 8 mL / min, and the stirring speed is 400 rpm;

[0029] Stearic acid: temperature controlled at 95-100°C, addition rate at 6 mL / min, stirring speed at 450 rpm;

[0030] Oleic acid: The temperature was controlled at 100°C, the addition rate was 5 mL / min, and the stirring speed was 500 rpm;

[0031] Propionic acid: The temperature was controlled at 100°C and then cooled to 85°C. The addition rate was 3 mL / min and the stirring speed was 350 rpm.

[0032] Furthermore, in step S7, samples are taken every 30 hours, and the pH value of the reaction solution is tested with pH test paper. When the pH is stable at 4.0 to 4.5 and no longer decreases, the salt formation is considered complete.

[0033] Furthermore, in step S8, the distillate from the first 30 minutes is collected and processed separately, and the distillate from the last 60 minutes is condensed, recovered, and recycled.

[0034] Furthermore, in step S9, the dripping time of tributyl borate is 30 minutes, the reaction is kept at 165° C. for 2 hours, and the transesterification rate is monitored to be ≥95%.

[0035] Furthermore, in the step S11, the cooling method is a water-cooled jacket, and the cooling rate is 5°C / min to below 40°C. After the discharge process, the material is passed through a 20-mesh sieve.

[0036] The beneficial effects of the present invention are:

[0037] 1. The rubber plasticizer of the present invention has a wide range of applications, including but not limited to improving the temperature stability of rubber, improving the plasticizing properties of rubber, reducing the viscosity of rubber, imparting flame retardancy to rubber, and inhibiting oxygen permeability.

[0038] 2. The present invention enables rubber products to adapt to different application requirements, such as automotive parts, wires and cables, sealing materials, etc. DETAILED DESCRIPTION

[0039] In order to further understand the content, features and effects of the present invention, the following examples are given to illustrate in detail.

[0040] Example 1:

[0041] The preparation method of a plasticizing cobalt salt for rubber comprises the following steps:

[0042] S1. Raw material preparation: 20 parts of cobalt hydroxide, 26 parts of isooctanoic acid, 7 parts of stearic acid, 2 parts of oleic acid, 16 parts of propionic acid, 20 parts of n-butyl propionate and 16.5 parts of tributyl borate;

[0043] S2. Raw material pretreatment:

[0044] Cobalt hydroxide: sieve through a 200-mesh sieve to remove lumps. After sieving, dry in a vacuum drying oven at 80°C for 4 hours to ensure that the moisture content is ≤0.5%;

[0045] Isooctanoic acid, stearic acid, oleic acid, and propionic acid: Purify by vacuum distillation at a pressure of -0.09 MPa, with temperatures controlled at 120°C, 225°C, 180°C, and 140°C, respectively, and an acid value controlled at 180 mgKOH / g to 200 mgKOH / g;

[0046] Butyl propionate was sieved with 3A molecular sieve and then dehydrated for 4 hours, with a water content of ≤100ppm;

[0047] Tributyl borate requires: nitrogen bubbling, deoxygenation for 30 minutes, flow rate of 0.5L / min;

[0048] S3. Add n-butyl propionate as a solvent to the reactor, preheat n-butyl propionate to 50° C., add it to the reactor, use a glass-lined reactor, and introduce nitrogen throughout the process;

[0049] S4. Add cobalt hydroxide and stir to form a pink suspension. Stir at 300 rpm. Slowly add cobalt hydroxide and continue stirring for 30 min until a uniform pink suspension is obtained.

[0050] S5. Raise the temperature to 90°C to 100°C at a rate of 2°C / min. Raise the temperature to 95°C and start the reflux device. The condensate flow rate in the reflux device is 10 L / min.

[0051] S6. Add 2-ethylhexanoic acid, stearic acid, oleic acid, and propionic acid dropwise in sequence, controlling the addition rate to avoid local overheating.

[0052] Isooctanoic acid: the temperature was controlled at 90-95°C, the addition rate was 8 mL / min, and the stirring speed was 400 rpm;

[0053] Stearic acid: temperature controlled at 95-100°C, addition rate at 6 mL / min, stirring speed at 450 rpm;

[0054] Oleic acid: The temperature was controlled at 100°C, the addition rate was 5 mL / min, and the stirring speed was 500 rpm;

[0055] Propionic acid: The temperature was controlled at 100°C and then cooled to 85°C. The addition rate was 3 mL / min and the stirring speed was 350 rpm.

[0056] S7, reflux reaction for 2 hours, and take samples every 30 hours, and use pH test paper to check the pH value of the reaction solution. When the pH is stable at 4.0-4.5 and no longer decreases, it is considered that the salt formation is complete, ensuring sufficient salt formation;

[0057] S8. Raise the temperature to 175°C to 185°C, distill under a vacuum of ≤-0.085 MPa for 1.5 hours, stir at 150 rpm, remove wastewater and residual solvent, collect and treat the distillate from the first 30 minutes separately, and condense and recover the distillate from the last 60 minutes for recycling;

[0058] S9, adding tributyl borate, keeping the temperature at 160-170°C for 2 hours, the addition time of tributyl borate is 30 minutes, keeping the temperature at 165°C for 2 hours, and monitoring the transesterification rate to be ≥95%;

[0059] S10, heating to 175°C to 185°C, and distilling at a negative pressure of ≤-0.085 MPa for 2 hours to remove the by-product n-butyl propionate;

[0060] S11, the material is cooled to obtain a blue solid, the cooling method is a water-cooled jacket, and the cooling rate is 5℃

[0061] / min, to below 40℃, and after discharging, pass through a 20-mesh sieve.

[0062] Example 2:

[0063] S1. Raw material preparation: 15 parts of cobalt hydroxide, 20 parts of isooctanoic acid, 8 parts of stearic acid, 3 parts of oleic acid, 15 parts of propionic acid, 15 parts of n-butyl propionate and 15 parts of tributyl borate;

[0064] S2. Raw material pretreatment:

[0065] Cobalt hydroxide: sieve through a 200-mesh sieve to remove lumps. After sieving, dry in a vacuum drying oven at 80°C for 4 hours to ensure that the moisture content is ≤0.5%;

[0066] Isooctanoic acid, stearic acid, oleic acid, and propionic acid: Purify by vacuum distillation at a pressure of -0.09 MPa, with temperatures controlled at 120°C, 225°C, 180°C, and 140°C, respectively, and an acid value controlled at 180 mgKOH / g to 200 mgKOH / g;

[0067] Butyl propionate was sieved with 3A molecular sieve and then dehydrated for 4 hours, with a water content of ≤100ppm;

[0068] Tributyl borate requires: nitrogen bubbling, deoxygenation for 30 minutes, flow rate of 0.5L / min;

[0069] S3. Add n-butyl propionate as a solvent to the reactor, preheat n-butyl propionate to 50° C., add it to the reactor, use a glass-lined reactor, and introduce nitrogen throughout the process;

[0070] S4. Add cobalt hydroxide and stir to form a pink suspension. Stir at 300 rpm. Slowly add cobalt hydroxide and continue stirring for 30 min until a uniform pink suspension is obtained.

[0071] S5. Raise the temperature to 90°C to 100°C at a rate of 2°C / min. Raise the temperature to 95°C and start the reflux device. The condensate flow rate in the reflux device is 10 L / min.

[0072] S6. Add 2-ethylhexanoic acid, stearic acid, oleic acid, and propionic acid dropwise in sequence, controlling the addition rate to avoid local overheating.

[0073] Isooctanoic acid: the temperature was controlled at 90-95°C, the addition rate was 8 mL / min, and the stirring speed was 400 rpm;

[0074] Stearic acid: temperature controlled at 95-100°C, addition rate at 6 mL / min, stirring speed at 450 rpm;

[0075] Oleic acid: The temperature was controlled at 100°C, the addition rate was 5 mL / min, and the stirring speed was 500 rpm;

[0076] Propionic acid: The temperature was controlled at 100°C and then cooled to 85°C. The addition rate was 3 mL / min and the stirring speed was 350 rpm.

[0077] S7, reflux reaction for 2 hours, and take samples every 30 hours, and use pH test paper to check the pH value of the reaction solution. When the pH is stable at 4.0-4.5 and no longer decreases, it is considered that the salt formation is complete, ensuring sufficient salt formation;

[0078] S8. Raise the temperature to 175°C to 185°C, distill under a vacuum of ≤-0.085 MPa for 1.5 hours, stir at 150 rpm, remove wastewater and residual solvent, collect and treat the distillate from the first 30 minutes separately, and condense and recover the distillate from the last 60 minutes for recycling;

[0079] S9, adding tributyl borate, keeping the temperature at 160-170°C for 2 hours, the addition time of tributyl borate is 30 minutes, keeping the temperature at 165°C for 2 hours, and monitoring the transesterification rate to be ≥95%;

[0080] S10, heating to 175°C to 185°C, and distilling at a negative pressure of ≤-0.085 MPa for 2 hours to remove the by-product n-butyl propionate;

[0081] S11, the material is cooled to obtain a blue solid, the cooling method is a water-cooled jacket, and the cooling rate is 5℃

[0082] / min, to below 40℃, and after discharging, pass through a 20-mesh sieve.

[0083] Example 3:

[0084] S1. Raw material preparation: 30 parts of cobalt hydroxide, 26 parts of isooctanoic acid, 7 parts of stearic acid, 10 parts of oleic acid, 16 parts of propionic acid, 20 parts of n-butyl propionate and 30 parts of tributyl borate;

[0085] S2. Raw material pretreatment:

[0086] Cobalt hydroxide: sieve through a 200-mesh sieve to remove lumps. After sieving, dry in a vacuum drying oven at 80°C for 4 hours to ensure that the moisture content is ≤0.5%;

[0087] Isooctanoic acid, stearic acid, oleic acid, and propionic acid: Purify by vacuum distillation at a pressure of -0.09 MPa, with temperatures controlled at 120°C, 225°C, 180°C, and 140°C, respectively, and an acid value controlled at 180 mgKOH / g to 200 mgKOH / g;

[0088] Butyl propionate was sieved with 3A molecular sieve and then dehydrated for 4 hours, with a water content of ≤100ppm;

[0089] Tributyl borate requires: nitrogen bubbling, deoxygenation for 30 minutes, flow rate of 0.5L / min;

[0090] S3. Add n-butyl propionate as a solvent to the reactor, preheat n-butyl propionate to 50° C., add it to the reactor, use a glass-lined reactor, and introduce nitrogen throughout the process;

[0091] S4. Add cobalt hydroxide and stir to form a pink suspension. Stir at 300 rpm. Slowly add cobalt hydroxide and continue stirring for 30 min until a uniform pink suspension is obtained.

[0092] S5. Raise the temperature to 90°C to 100°C at a rate of 2°C / min. Raise the temperature to 95°C and start the reflux device. The condensate flow rate in the reflux device is 10 L / min.

[0093] S6. Add 2-ethylhexanoic acid, stearic acid, oleic acid, and propionic acid dropwise in sequence, controlling the addition rate to avoid local overheating.

[0094] Isooctanoic acid: the temperature was controlled at 90-95°C, the addition rate was 8 mL / min, and the stirring speed was 400 rpm;

[0095] Stearic acid: temperature controlled at 95-100°C, addition rate at 6 mL / min, stirring speed at 450 rpm;

[0096] Oleic acid: The temperature was controlled at 100°C, the addition rate was 5 mL / min, and the stirring speed was 500 rpm;

[0097] Propionic acid: The temperature was controlled at 100°C and then cooled to 85°C. The addition rate was 3 mL / min and the stirring speed was 350 rpm.

[0098] S7, reflux reaction for 2 hours, and take samples every 30 hours, and use pH test paper to check the pH value of the reaction solution. When the pH is stable at 4.0-4.5 and no longer decreases, it is considered that the salt formation is complete, ensuring sufficient salt formation;

[0099] S8. Raise the temperature to 175°C to 185°C, distill under a vacuum of ≤-0.085 MPa for 1.5 hours, stir at 150 rpm, remove wastewater and residual solvent, collect and treat the distillate from the first 30 minutes separately, and condense and recover the distillate from the last 60 minutes for recycling;

[0100] S9, adding tributyl borate, keeping the temperature at 160-170°C for 2 hours, the addition time of tributyl borate is 30 minutes, keeping the temperature at 165°C for 2 hours, and monitoring the transesterification rate to be ≥95%;

[0101] S10, heating to 175°C to 185°C, and distilling at a negative pressure of ≤-0.085 MPa for 2 hours to remove the by-product n-butyl propionate;

[0102] S11. The discharged material is cooled to obtain a blue solid. The cooling method is a water-cooled jacket and the cooling rate is 5°C / min to below 40°C. After the discharge process, the solid is passed through a 20-mesh sieve.

[0103] Table 1 Test data of plasticized cobalt salts of Examples 1 to 3

[0104]

[0105] Table 2 Test data of plasticized cobalt salts of Examples 1 to 3

[0106]

[0107] From the above examples, it can be seen that, under the same conditions, the present invention improves the temperature stability of rubber, improves the plasticization of rubber, reduces the viscosity of rubber, imparts flame retardancy to rubber, and inhibits oxygen permeability. These properties enable rubber products to adapt to different application requirements.

[0108] The above shows and describes the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The above embodiments and descriptions are merely preferred examples of the present invention and are not intended to limit the present invention. Various changes and improvements may be made to the present invention without departing from the spirit and scope of the present invention. Such changes and improvements fall within the scope of the present invention. The scope of protection claimed in the present invention is defined by the appended claims and their equivalents.

Claims

1. A method for preparing a plasticizing cobalt salt for rubber, characterized in that: The following steps are involved: S1. Raw material preparation: 20 to 30 parts of cobalt hydroxide, 15 to 26 parts of isooctanoic acid, 7 to 10 parts of stearic acid, 2 to 5 parts of oleic acid, 10 to 16 parts of propionic acid, 20 to 30 parts of n-butyl propionate, and 10 to 16.5 parts of tributyl borate; S2. Raw material pretreatment: Cobalt hydroxide: sieve through a 200-mesh sieve to remove lumps. After sieving, dry in a vacuum drying oven at 80°C for 4 hours to ensure that the moisture content is ≤0.5%; Isooctanoic acid, stearic acid, oleic acid, and propionic acid: Purify by vacuum distillation at a pressure of -0.09 MPa, with temperatures controlled at 120°C, 225°C, 180°C, and 140°C, respectively, and an acid value controlled at 180 mgKOH / g to 200 mgKOH / g; Butyl propionate was sieved with 3A molecular sieve and then dehydrated for 4 hours, with a water content of ≤100ppm; Tributyl borate requires: nitrogen bubbling, deoxygenation for 30 minutes, flow rate of 0.5L / min; S3, adding n-butyl propionate as a solvent to the reactor, first preheating n-butyl propionate to 50° C., and adding it to the reactor; S4. Add cobalt hydroxide and stir to form a pink suspension. Stir at 300 rpm. Slowly add cobalt hydroxide and continue stirring for 30 min until a uniform pink suspension is obtained. S5. Raise the temperature to 90°C to 100°C and start the reflux device; S6. Add 2-ethylhexanoic acid, stearic acid, oleic acid, and propionic acid dropwise in sequence, controlling the addition rate to avoid local overheating. S7, reflux reaction for 2h to ensure sufficient salt formation; S8. Raise the temperature to 175°C to 185°C, distill under a vacuum of ≤-0.085 MPa for 1.5 hours, and stir at 150 rpm to remove wastewater and residual solvent; S9, adding tributyl borate, and keeping the temperature at 160°C to 170°C for 2 hours. During the reaction, adding an organotin catalyst accounting for 0.1% to 0.5% of the total material; S10, raising the temperature to 175°C to 185°C, and distilling at a negative pressure of ≤-0.085 MPa for 2 hours to remove the by-product n-butyl propionate; S11, discharge the cooled blue solid.

2. The method for preparing the plasticizing cobalt salt for rubber according to claim 1, wherein: In step S2, after the cobalt hydroxide is sieved and dried, a laser particle size analyzer is used to detect its particle size distribution to ensure that the particle size is between 1 μm and 10 μm, and the proportion of particles within the appropriate range reaches 90%; The condensation temperature of isooctanoic acid, stearic acid, oleic acid and propionic acid can be set to 50℃~60℃, and the acid value can be tested by automatic potentiometric titrator; Before using 3A molecular sieve to screen n-butyl propionate, the 3A molecular sieve is first activated at 300° C. for 4 to 6 hours.

3. The method for preparing the plasticizing cobalt salt for rubber according to claim 1, wherein: In step S3, a glass-lined reactor is used, and nitrogen is introduced throughout the process; n-Butyl propionate was slowly and evenly added to the reactor using a peristaltic pump, with the addition rate set at 8 ml / min to 10 ml / min.

4. The method for preparing the plasticizing cobalt salt for rubber according to claim 1, wherein: In step S4, during the process of slowly adding cobalt hydroxide, it is necessary to check the color change and uniformity of the suspension in the reactor through the observation window.

5. The method for preparing the plasticizing cobalt salt for rubber according to claim 1, wherein: In step S5, the temperature is raised to 95°C at a rate of 2°C / min, and the condensing water is turned on with a flow rate of 10 L / min, and a spherical condenser is used as a reflux device.

6. The method for preparing the plasticizing cobalt salt for rubber according to claim 1, wherein: In step S6, isooctanoic acid: the temperature is controlled at a constant temperature of 90° C. to 95° C., the dropwise addition rate is 8 mL / min, and the stirring speed is 400 rpm; Stearic acid: temperature controlled at 95-100°C, addition rate at 6 mL / min, stirring speed at 450 rpm; Oleic acid: The temperature was controlled at 100°C, the addition rate was 5 mL / min, and the stirring speed was 500 rpm; Propionic acid: The temperature was controlled at 100°C and then cooled to 85°C. The addition rate was 3 mL / min and the stirring speed was 350 rpm.

7. The method for preparing the plasticizing cobalt salt for rubber according to claim 4, wherein: In step S7, samples are taken every 30 hours, and the pH value of the reaction solution is tested with pH test paper. When the pH is stable at 4.0 to 4.5 and no longer decreases, the salt formation is considered complete.

8. The method for preparing the plasticizing cobalt salt for rubber according to claim 1, wherein: In step S8, the distillate from the first 30 minutes is collected and processed separately, and the distillate from the last 60 minutes is condensed, recovered, and then recycled.

9. The method for preparing the plasticizing cobalt salt for rubber according to claim 1, wherein: In step S9, the addition time of tributyl borate is 30 minutes, the reaction is kept at 165° C. for 2 hours, and the transesterification rate is monitored to be ≥95%.

10. The method for preparing a plasticizing cobalt salt for rubber according to claim 1, wherein: In the step S11, the cooling method is a water-cooled jacket, and the cooling rate is 5°C / min, to below 40°C. After the discharge process, the material is passed through a 20-mesh sieve.

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