CN110054912B - A method and product for preparing rubber filler based on shrimp and crab base shell pyrolysis - Google Patents

Abstract

The invention belongs to the technical field related to rubber filler preparation, and discloses a method for preparing rubber filler based on shrimp and crab-based shell pyrolysis, which comprises the following steps: pretreating shrimp and crab shells; preparing pyrolytic carbon by pyrolyzing a shell powder sample; and (5) cleaning, drying and grinding the pyrolytic carbon. Wherein the design of the reaction participants and the pyrolysis process route can ensure that nano-scale calcium carbonate particles are obtained, and simultaneously the high rigidity and high toughness of the filler are improved by combining with organic components. In addition, the special auxiliary agent is added in the pyrolytic carbon post-treatment process, and practical tests show that the performances of the rubber such as rigidity, tensile strength, permeability, flame retardance, heat resistance and the like can be improved. The invention also discloses a corresponding rubber filler product. The invention has the advantages of relatively simple process flow, easily regulated reaction conditions and lower preparation cost, can reduce the environmental pollution caused by the disposal of the shrimp and crab shells, and realizes resource utilization.

Description

A method and product for preparing rubber filler based on shrimp and crab base shell pyrolysis

technical field

The invention belongs to the technical field related to the preparation of rubber fillers, and more particularly relates to a method and a product for preparing rubber fillers based on the pyrolysis of shrimp and crab-based shells.

Background technique

As we all know, calcium carbonate, as one of the most important inorganic fillers, is widely used in rubber, plastic, paper and other industries. The influence of rubber fillers on the mechanical properties of polymers mainly depends on their particle size, shape, surface properties and degree of dispersion. For calcium carbonate, its biggest problem as a rubber filler is its hydrophilicity, which leads to non-uniform bonding with the polymer matrix interface and non-uniform dispersion, thereby affecting the mechanical properties of the material. Due to the poor dispersion of pure calcium carbonate particles in the polymer matrix, a large number of researchers have used coupling agents or reactive surface modifiers with better hydrophobicity to surface calcium carbonate by adsorption or surface coating. Organic modification with a view to improving its dispersing properties.

For example, invention patent CN106830043 A discloses a method of compounding aluminate coupling agent, silane, lauric acid, and non-ionic surfactant as modifier, and modifying nano-calcium carbonate on the surface; , Invention Patent CN104084059A discloses a preparation method for filling silicone rubber composite film with hydrophobically modified nano-calcium carbonate with one or a mixture of oleic acid and stearic acid as modifier. However, further research shows that these methods usually use technical grade calcium carbonate, and need to use higher-priced compounds in the modification process, which increases the cost of using calcium carbonate fillers. On the other hand, the modification conditions of calcium carbonate are relatively harsh, and the addition of modifiers will often have a partial negative impact on the properties of the polymer. Correspondingly, there is an urgent need to make further improvements in this field in order to meet the requirements for the preparation of rubber fillers with higher quality and efficiency requirements.

SUMMARY OF THE INVENTION

In view of the above deficiencies and improvement needs of the prior art, the present invention provides a method and product for preparing rubber fillers based on the pyrolysis of shrimp and crab base shells, wherein the shrimp and crab base shells are specially selected as the source of calcium carbonate, and the The matching pyrolysis process route and reaction mechanism are further designed in a targeted manner, correspondingly, the combination of calcium carbonate and organic matter can be used to improve the high stiffness and high toughness of the material. Improve production efficiency and product quality.

In order to achieve the above object, according to one aspect of the present invention, a method for preparing a rubber filler based on the pyrolysis of shrimp and crab base shells is provided, characterized in that the method comprises the following steps:

(a) Pretreatment steps of shrimp and crab shells

The shrimp and crab base shells are cleaned and then crushed to obtain shell crushed materials with an average size of 0.5 cm to 2 cm;

(b) Preparation steps of target pyrolytic carbon

The shell crushed material is put into a reactor with a built-in heat transfer medium ball, and the pyrolysis treatment is carried out under the protection of inert gas, wherein the internal temperature of the reactor is set to 300℃～1000℃, and the pyrolysis time is set 20min～24h;

During this process, the shell crushed material is thermally decomposed into semi-coke components and volatile components. The semi-coke components move together with the lifting plate in the reactor, and are continuously impacted and assisted by the heat transfer medium balls. heat, and at the same time interact with the volatile matter, and finally generate the target pyrolytic carbon;

(c) Cleaning, drying and grinding treatment steps of pyrolytic carbon

The target pyrolytic carbon generated in step (b) is washed with organic solvent and deionized water in turn, and filtered to obtain clean pyrolytic carbon; the pyrolytic carbon is placed in an oven at 50° C. to 105° C. to dry for a certain period of time. , so that the moisture content is lower than 5%, then the dry pyrolytic carbon is placed in a grinder and additives are added to fully grind to obtain a final product with an average particle size of 3 μm to 50 μm, thereby obtaining the desired rubber filler product ;

Wherein the auxiliary agent is selected from one or a mixture of the following substances, and its addition amount accounts for 3‰～1% of the mass of the dried pyrolytic carbon: triethanolamine, diethylene glycol amine, 2-hydroxyethyl alcohol Amine, undecylenal, polyamide resin, glycerin, polyethylene wax, oxidized polyethylene wax, phthalic acid, palmitic acid.

As a further preference, in step (b), an external heat source is preferably used to heat the reactor; the heat transfer medium balls are preferably sent into the reactor after external heating, and these heat transfer medium balls It is preferably heated to a temperature of 500°C to 1100°C.

As a further preference, in step (b), the generated target pyrolytic carbon contains lipophilic groups such as hydrocarbon groups and ester groups and hydrophilic groups such as hydroxyl groups and carboxyl groups, so as to promote the interface between the polymer matrix and the polymer matrix in this way. Coupling of calcium carbonate surface, and the modification process of calcium carbonate can be omitted.

As a further preference, in step (c), the target pyrolytic carbon is preferably cleaned by ultrasonic cleaning, and the ultrasonic frequency is set to 30kHz-90kHz, and the cleaning time is 1h-9h.

As a further preference, in step (c), a final product with an average particle size of 25 μm˜30 μm is preferably obtained after sufficient grinding.

As a further preference, the obtained rubber filler is preferably used in an amount of 1 phr to 12 phr to prepare rubber.

According to another aspect of the present invention, a corresponding rubber filler product is also provided.

As a further preference, in the above-mentioned rubber filler product, the particle size of calcium carbonate is nano-scale, and the phenomenon of agglomeration is not easy to occur.

As a further preference, the specific surface area of the above rubber filler product is 30 m ² /g or more.

In general, compared with the prior art, the above technical solutions conceived by the present invention mainly have the following technical advantages:

1. In the present invention, the shrimp and crab shells are introduced as the source of calcium carbonate, and the pyrolysis process route is designed according to the composition and structural characteristics of the shrimp and crab shells. The pyrolysis product is a pyrolysis product rich in nanoscale calcium carbonate. Carbon, as well as organic groups with coupling effect, correspondingly provide a new technical direction for the preparation of chemical products;

2. In particular, by redesigning the key parameters and operating steps in the pyrolysis process route, the distribution of organic matter in the pyrolysis carbon causes calcium carbonate to be separated during the crystallization process, and the particle size of the crystallized calcium carbonate can reach nanometer level, In addition, it has good dispersibility in pyrolytic carbon, and is not easy to agglomerate; the combination of calcium carbonate and organic matter can respectively ensure high stiffness and high toughness of the material, thereby improving the application range of the material;

3. On the other hand, due to the interaction between the semi-coke and the volatiles during the pyrolysis reaction, the hydrogen radicals from the secondary reaction of the volatiles occupy various active sites in the semi-coke, which promotes chitin, amino acids, lipids, etc. At the same time, the inorganic components in the shrimp shell play a certain catalytic role, and the final residual organic matter contains lipophilic groups such as hydrocarbon groups and ester groups, as well as hydrophilic groups such as hydroxyl and carboxyl groups, which can Effectively promote the coupling between the polymer matrix interface and the calcium carbonate surface; compared with unmodified nano-calcium carbonate, pyrolytic carbon as a filler eliminates the modification step, improves production efficiency and reduces production costs.

4. Compared with the ordinary calcium carbonate filler, the shrimp and crab bio-based rubber filler prepared according to the present invention has a significantly larger specific surface area of the nanoparticle filler, which is beneficial to the strong interfacial bonding between the filler and the polymer matrix, thereby improving the Polymer properties; in addition, by adding special additives in the present invention, actual tests show that the properties such as stiffness, tensile strength, permeability, flame retardancy and heat resistance of rubber can also be effectively improved.

Description of drawings

1 is a schematic diagram of the overall process flow of the method for preparing rubber fillers by pyrolysis, which is constructed according to the present invention, taking shrimp and crab-based shells as an example.

Detailed ways

In order to make the objectives, technical solutions and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention, but not to limit the present invention. In addition, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

FIG. 1 is a schematic diagram of the overall process flow of the method for preparing rubber fillers by pyrolysis constructed according to the present invention. As shown in FIG. 1, the present invention can significantly improve the quality of the final obtained filler product compared with the existing technology by researching and improving the treatment mode, reaction mechanism and multiple key parameters of the entire process. It has the advantages of easy regulation of reaction conditions, high efficiency and low cost. In addition, it also helps to effectively reduce the environmental pollution caused by the disposal of shrimp and crab shells, and realize the comprehensive utilization of resources.

According to the basic concept of the present invention, the method for preparing rubber filler based on the pyrolysis of shrimp and crab base shell mainly comprises the following steps:

First, it is the pretreatment step of shrimp and crab shells.

The shrimp and crab base shells are cleaned and then crushed to obtain shell crushed materials with an average size of 0.5 cm to 2 cm;

Next, is the preparation step of the target pyrolytic carbon.

The shell crushed material is put into a reactor with a built-in heat transfer medium ball, and the pyrolysis treatment is carried out under the protection of inert gas, wherein the internal temperature of the reactor is set to 300℃～1000℃, and the pyrolysis time is set For 20min ~ 24h.

During this process, the shell crushed material is thermally decomposed into semi-coke components and volatile components. The semi-coke components move together with the lifting plate in the reactor, and are continuously impacted and assisted by the heat transfer medium balls. heat, while interacting with the volatiles, and finally generating the target pyrolytic carbon.

Finally, there are the steps of cleaning, drying and grinding the pyrolytic carbon.

The generated target pyrolytic carbon is washed with organic solvent and deionized water in turn, and filtered to obtain clean pyrolytic carbon; the pyrolytic carbon is dried in an oven at 50°C to 105°C for a certain period of time to make it water-containing. If the ratio is less than 5%, then the dry pyrolytic carbon is placed in a grinding machine and additives are added to fully grind to obtain a final product with an average particle size of 3 μm to 50 μm, thereby obtaining the desired rubber filler product;

Wherein the auxiliary agent is selected from one or a mixture of the following substances, and its addition amount accounts for 3‰～1% of the mass percentage of the dried pyrolytic carbon: triethanolamine, diethylene glycol amine, 2-hydroxyethylamine , Undecenal, polyamide resin, glycerin, polyethylene wax, oxidized polyethylene wax, phthalic acid, palmitic acid.

The present invention will be more clearly explained by some specific embodiments below.

Example 1

(1) Shell pretreatment: after washing the shrimp shell with clean water, it is subjected to crushing treatment to obtain a shell powder sample with a particle size of 0.5 to 1 cm;

(2) Preparation of pyrolytic carbon by pyrolyzing the shell powder sample: heating the shell powder sample placed in the reactor by an external heat source, and controlling the internal temperature of the reactor to be 450 °C, the temperature of the heat transfer medium bulb is about 570 °C, and the heat The decomposition time is 8h; before the pyrolysis starts, an excess of inert gas is introduced into the reactor to discharge air, and the ventilation is stopped after the reaction starts, and the shell crushed material is decomposed into semi-coke components and volatile components by heating, and the semi-coke components follow the reaction. The lifting plate in the device moves together, and is continuously impacted by the heat transfer medium ball and assists heat transfer, and at the same time interacts with the volatile matter, and finally generates the target pyrolytic carbon;

(3) Cleaning treatment of pyrolytic carbon: first, use an organic solvent to clean a small amount of tar attached to the surface of the pyrolytic carbon, and then use deionized water to clean the residual organic solvent on the surface of the pyrolytic carbon; the cleaning process is carried out on an ultrasonic cleaner with a frequency of 30kHz, cleaning time is 9h;

(4) Drying and grinding treatment of pyrolytic carbon: filter the cleaning agent to obtain clean pyrolytic carbon, put the pyrolytic carbon in an oven at 105°C, and its moisture content is lower than 2% after drying; The carbon is placed in a grinding machine, and after adding 3‰ of triethanolamine auxiliary, it is fully ground for 12 hours to obtain a pyrolytic carbon sample with a particle size of 3-6 μm; when used as a rubber formulation, the filler content is controlled at 8 phr.

The properties of the rubber mixed with the pyrolytic carbon filler in Example 1 were tested, and its density, hardness, tensile strength, and elongation at break are shown in Table 1.

Table 1 Rubber performance parameter table

Performance density hardness Tensile Strength Elongation at break unit g/cm³ Shore A degree Mpa % National standard GB4472-84 GB/T531-1999 GB/T528-1998 GB/T528-1998 Example 1 1.65 78 4.50 500

Example 2

(1) Shell pretreatment: after washing the shrimp shell with clean water, it is subjected to crushing treatment to obtain a shell powder sample with a particle size of 1 to 2 cm;

(2) Pyrolysis of shell powder samples to prepare pyrolytic carbon: the shell powder samples placed in the reactor are heated by an external heat source, and the internal temperature of the reactor is controlled by a program to be 300 °C, the heat transfer medium bulb temperature is about 500 °C, and the heat The decomposition time is 24h; before the pyrolysis begins, an excess of inert gas is introduced into the reactor to discharge air, and the ventilation is stopped after the reaction begins, and the shell crushed material is decomposed into semi-coke components and volatiles by heating, and the semi-coke components follow the reaction. The lifting plate in the device moves together, and is continuously impacted by the heat transfer medium ball and assists heat transfer, and at the same time interacts with the volatile matter, and finally generates the target pyrolytic carbon;

(3) Cleaning treatment of pyrolytic carbon: first, use an organic solvent to clean a small amount of tar attached to the surface of the pyrolytic carbon, and then use deionized water to clean the residual organic solvent on the surface of the pyrolytic carbon; the cleaning process is carried out on an ultrasonic cleaner with a frequency of 40kHz, cleaning time is 7h;

(4) Drying and grinding treatment of pyrolytic carbon: filter the cleaning agent to obtain clean pyrolytic carbon, put the pyrolytic carbon in an oven at 105°C, and its moisture content is lower than 2% after drying; The carbon was placed in a grinding machine, and after adding 20‰ of diethylene glycol amine auxiliary, it was fully ground for 10 hours to obtain a pyrolytic carbon sample with a particle size of 6-12 μm; when used as a rubber formulation, the filler content was controlled to be 12 phr.

Example 3

(1) Shell pretreatment: after cleaning the crab shell with clean water, it is subjected to crushing treatment to obtain a shell powder sample with a particle size of 1 to 1.5 cm;

(2) Pyrolysis of shell powder samples to prepare pyrolytic carbon: the shell powder samples placed in the reactor are heated by an external heat source, and the internal temperature of the reactor is controlled by a program to be 600 °C, the temperature of the heat transfer medium ball is about 660 °C, and the heat The decomposition time is 5.5h; before the pyrolysis starts, an excess of inert gas is introduced into the reactor to exhaust air, and the ventilation is stopped after the reaction starts, and the shell crushed material is decomposed into semi-coke components and volatile components by heating, and the semi-coke components are decomposed into semi-coke components and volatile components with the The lifting plate in the reactor moves together, and is continuously hit by the heat transfer medium ball and assists heat transfer, and at the same time interacts with the volatile matter, and finally generates the target pyrolysis carbon;

(3) Cleaning treatment of pyrolytic carbon: first, use an organic solvent to clean a small amount of tar attached to the surface of the pyrolytic carbon, and then use deionized water to clean the residual organic solvent on the surface of the pyrolytic carbon; the cleaning process is carried out on an ultrasonic cleaner with a frequency of 50kHz, cleaning time is 5h;

(4) Drying and grinding treatment of pyrolytic carbon: filter the cleaning agent to obtain clean pyrolytic carbon, put the pyrolytic carbon in an oven at 105°C, and its moisture content is lower than 2% after drying; The carbon was placed in a grinding machine, and 80‰ of 2-hydroxyethylamine was added, and then fully ground for 8 hours to obtain a pyrolytic carbon sample with a particle size of 12-20 μm; as a rubber formulation, the filler content was controlled at 9 phr.

Example 4

(1) Shell pretreatment: after cleaning the crab shell with clean water, it is subjected to crushing treatment to obtain a shell powder sample with a particle size of 1 to 2 cm;

(2) Preparation of pyrolytic carbon by pyrolyzing the shell powder sample: heating the shell powder sample placed in the reactor by an external heat source, and controlling the internal temperature of the reactor to be 710 °C, the temperature of the heat transfer medium bulb is about 780 °C, and the heat The decomposition time is 3.5h; before the pyrolysis starts, an excess of inert gas is introduced into the reactor to discharge air, and the ventilation is stopped after the reaction starts, and the shell crushed material is decomposed into semi-coke components and volatile components by heating. The lifting plate in the reactor moves together, and is continuously hit by the heat transfer medium ball and assists heat transfer, and at the same time interacts with the volatile matter, and finally generates the target pyrolysis carbon;

(3) Cleaning treatment of pyrolytic carbon: first, use an organic solvent to clean a small amount of tar attached to the surface of the pyrolytic carbon, and then use deionized water to clean the residual organic solvent on the surface of the pyrolytic carbon; the cleaning process is carried out on an ultrasonic cleaner with a frequency of 70kHz, cleaning time is 4h;

(4) Drying and grinding treatment of pyrolytic carbon: filter the cleaning agent to obtain clean pyrolytic carbon, put the pyrolytic carbon in an oven at 50°C, and its moisture content is lower than 5% after drying; The carbon is placed in a grinding machine, and after adding 0.1% of undecylenal and polyamide resin as an auxiliary, it is fully ground for 6 hours to obtain a pyrolytic carbon sample with a particle size of 20 to 25 μm; when used as a rubber formulation, the filler The amount of incorporation was controlled at 6 phr.

Example 5

(1) Shell pretreatment: After washing the mixture of shrimp and crab shells each accounting for 50% with clean water, it is crushed to obtain a shell powder sample with a particle size of 0.5 to 1.5 cm;

(2) Pyrolysis of shell powder samples to prepare pyrolytic carbon: the shell powder samples placed in the reactor are heated by an external heat source, and the internal temperature of the reactor is controlled by a program to be 750 °C, the temperature of the heat transfer medium ball is about 800 °C, and the heat The decomposition time is 1.5h; before the pyrolysis starts, an excess of inert gas is introduced into the reactor to discharge air, and the ventilation is stopped after the reaction starts, and the shell crushed material is decomposed into semi-coke components and volatile components by heating. The lifting plate in the reactor moves together, and is continuously hit by the heat transfer medium ball and assists heat transfer, and at the same time interacts with the volatile matter, and finally generates the target pyrolysis carbon;

(3) Cleaning treatment of pyrolytic carbon: first, use an organic solvent to clean a small amount of tar attached to the surface of the pyrolytic carbon, and then use deionized water to clean the residual organic solvent on the surface of the pyrolytic carbon; the cleaning process is carried out on an ultrasonic cleaner with a frequency of 80kHz, cleaning time is 3h;

(4) Drying and grinding treatment of pyrolytic carbon: filter the cleaning agent to obtain clean pyrolytic carbon, put the pyrolytic carbon in an oven at 50°C, and its moisture content is lower than 5% after drying; The carbon is placed in a grinding machine, after adding 0.5% of glycerol and polyethylene wax as an additive, fully ground for 5 hours to obtain a pyrolytic carbon sample with a particle size of 25-30 μm; as a rubber formulation, the amount of the filler added Control is 4phr.

Example 6

(1) Shell pretreatment: after washing the mixture of shrimp and crab shells each accounting for 50% with clean water, it is crushed to obtain a shell powder sample with a particle size of 1.5 to 2 cm;

(2) Pyrolysis of shell powder samples to prepare pyrolytic carbon: the shell powder samples placed in the reactor are heated by an external heat source, and the internal temperature of the reactor is controlled by a program to be 1000 °C, the heat transfer medium bulb temperature is about 1100 °C, and the heat The decomposition time is 20min; before the pyrolysis begins, an excess of inert gas is introduced into the reactor to discharge air, and the ventilation is stopped after the reaction begins, and the shell crushed material is decomposed into semi-coke components and volatiles by heating, and the semi-coke components follow the reaction. The lifting plate in the device moves together, and is continuously impacted by the heat transfer medium ball and assists heat transfer, and at the same time interacts with the volatile matter, and finally generates the target pyrolytic carbon;

(3) Cleaning treatment of pyrolytic carbon: first, use an organic solvent to clean a small amount of tar attached to the surface of the pyrolytic carbon, and then use deionized water to clean the residual organic solvent on the surface of the pyrolytic carbon; the cleaning process is carried out on an ultrasonic cleaner with a frequency of 90kHz, cleaning time is 1h;

(4) Drying and grinding treatment of pyrolytic carbon: filter the cleaning agent to obtain clean pyrolytic carbon, put the pyrolytic carbon in an oven at 50°C, and its moisture content is lower than 5% after drying; The carbon was placed in a grinding machine, and after adding 1% oxidized polyethylene wax, phthalic acid and palmitic acid, the auxiliary agent was fully ground for 4 hours to obtain a pyrolytic carbon sample with a particle size of 30-50 μm; In the rubber formulation, the filler content is controlled to be 1 phr.

Those skilled in the art can easily understand that the above are only preferred embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present invention, etc., All should be included within the protection scope of the present invention.

Claims (9)

1. a method for preparing rubber filler based on shrimp and crab base shell pyrolysis, is characterized in that, the method comprises the following steps: (a) Pretreatment steps of shrimp and crab shells The shrimp and crab base shells are cleaned and then crushed to obtain shell crushed materials with an average size of 0.5 cm to 2 cm; (b) Preparation steps of target pyrolytic carbon The shell crushed material is put into a reactor with a built-in heat transfer medium ball, and the pyrolysis treatment is carried out under the protection of inert gas, wherein the internal temperature of the reactor is set to 300℃～1000℃, and the pyrolysis time is set 20min～24h; During this process, the shell crushed material is thermally decomposed into semi-coke components and volatile components. The semi-coke components move together with the lifting plate in the reactor, and are continuously impacted and assisted by the heat transfer medium balls. heat, and at the same time interact with the volatile matter, and finally generate the target pyrolytic carbon; (c) Cleaning, drying and grinding treatment steps of pyrolytic carbon The target pyrolytic carbon generated in step (b) is washed with organic solvent and deionized water in turn, and filtered to obtain clean pyrolytic carbon; the pyrolytic carbon is placed in an oven at 50°C to 105°C to dry for a certain period of time. , so that the moisture content is lower than 5%, then the dry pyrolytic carbon is placed in a grinder and additives are added to fully grind to obtain a final product with an average particle size of 3 μm to 50 μm, thereby obtaining the desired rubber filler product ; Wherein, the auxiliary agent is selected from triethanolamine, diethylene glycol amine, 2-hydroxyethylamine, undecylenal, polyamide resin, glycerin, polyethylene wax, oxidized polyethylene wax, phthalic acid, palmitic acid One or a mixture of them, and the added amount accounts for 3‰ to 1% of the mass of the dried pyrolytic carbon. 2 . The method according to claim 1 , wherein in step (b), an external heat source is used to heat the reactor; the heat transfer medium balls are externally heated and then fed into the reactor. 3 . and these heat transfer medium balls are heated to a temperature of 500°C to 1100°C. 3. The method according to claim 1 or 2, characterized in that, in step (b), the generated target pyrolytic carbon contains a lipophilic group of a hydrocarbon group or an ester group and a hydrophilic group of a hydroxyl group or a carboxyl group In this way, the coupling between the polymer matrix interface and the calcium carbonate surface can be promoted, and the modification treatment process of calcium carbonate can be omitted. 4 . The method of claim 1 , wherein in step (c), the target pyrolytic carbon is cleaned by ultrasonic cleaning, and the ultrasonic frequency is set to 30 kHz to 90 kHz, and the cleaning time is 1 h to 1 h. 5 . 9h. 5 . The method of claim 1 , wherein in step (c), a final product with an average particle size of 25 μm to 30 μm is obtained after sufficient grinding. 6 . 6 . The method of claim 1 , wherein the rubber filler is prepared in an amount of 1 phr to 12 phr. 7 . 7. A rubber filler product prepared by the method of any one of claims 1-6. 8 . The rubber filler product according to claim 7 , wherein, in the rubber filler product, the particle size of calcium carbonate is nano-scale, and agglomeration is not easy to occur. 9 . 9 . The rubber filler product according to claim 7 , wherein the specific surface area of the rubber filler product is 30 m ² /g or more. 10 .

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