JPH06179215A - Method for pulverizing vulcanized rubber material - Google Patents

Abstract

PURPOSE:To pulverize waste of a rubber material into finely-divided powder efficiently and continuously in a simple process by applying a shearing force to granular waste of a vulcanized rubber material at a specific temperature. CONSTITUTION:In a method for pulverizing a vulcanized rubber material, a shearing force is applied to granular waste of a vulcanized rubber material at a temperature of 230 deg.C or lower. This is because at a temperature higher than 230 deg.C, a malodor may be generated and the pulverized waste may be thermally fused. When the waste is supplied to a shearing force application device, the waste is granulated to a granular material of a predetermined particle diameter by a granulator or the like for preventing the occurrence of blocking or surging in the loading means of the shearing force application device. If a shearing force is applied after an agent belonging to an anti-blocking agent is added to the waste to be pulverized, the adhesion and cohesion of the rubber material can be prevented.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for pulverizing a vulcanized rubber-based material for pulverizing a waste product of a vulcanized rubber-based material and the like for effective use.

[0002]

2. Description of the Related Art In recent years, resource saving and energy saving have been demanded in all industries, and scraps of resin moldings (hereinafter abbreviated as "waste materials") are effectively reclaimed in the industrial field where resin materials are used. It is desired to use it.

Conventionally, as a method for utilizing a waste material of a resin material, there is a first method in which the waste material and a virgin material (new resin having no heat history) are mixed at a fixed ratio and subjected to molding again. There is a method of using waste materials as a filler or a fuel. The first method is applied to so-called engineering plastics having a high cost as a resin material, for example, polyether sulfone, polyether ether ketone, polyimide, etc., and the second method is a low-cost material such as polyethylene and polyethylene.
For example, non-crosslinked or crosslinked polyethylene resin such as ethylene-propylene copolymer, ethylene-vinyl acetate copolymer, ethylene-ethyl acrylate copolymer, or rubber material, especially vulcanized rubber for imparting high elasticity. Applied to system materials.

Conventionally, a method for pulverizing waste materials of resin materials and rubber materials has been described in A. Coarse crushing ... roughly crushing to about 20 mm B. Medium crushing ... Crushing to medium fine particles of about 10 mm to 1 mm. Fine pulverization: It is known that three pulverization steps of pulverization into fine particles of micron order are required. This pulverization method has a number of steps and is difficult to process continuously, so that there is a problem that the cost becomes high and the merit of using the waste material is lost.

[0005]

SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and provides a method capable of continuously and efficiently pulverizing waste material made of a vulcanized rubber-based material by a simple process. The purpose is to do.

[0006]

DISCLOSURE OF THE INVENTION The present invention provides a method for atomizing a vulcanized rubber-based material, which comprises applying a shearing force to a waste material made of granular vulcanized rubber-based material at a temperature of 230 ° C. or less. provide.

Here, as the vulcanized rubber material to which the present invention is applied, natural rubber (NR), butadiene rubber (BR), styrene-butadiene rubber (SBR), acrylonitrile-butadiene rubber (NBR), isoprene Diene-based synthetic rubbers such as rubber (IR) and chloroprene rubber (CR); butyl rubber (IIR), ethylene-propylene rubber (EPM), ethylene-propylene terpolymer (EPDM), chlorosulphonated polyethylene (CS)
M) and other olefin-based synthetic rubbers; vinylidene fluoride, propylene hexafluoride and other fluorine-based rubbers; acrylic rubbers;
Silicone rubber; rubber-based materials such as urethane rubber are sulfur,
A rubber-based material that has plasticity and is made elastic by mixing it with a vulcanizing agent such as a peroxide, a metal oxide, a polyfunctional amine, or quinone dioxime to form a cross-linking bond between chain-like rubber molecules. Say.

Further, the waste materials of these vulcanized rubber materials mean all waste materials of industrial products and parts, including mastication accelerators, softening agents, fillers, vulcanization accelerators, processing aids, and antioxidants. A compounding agent such as an agent, an ozone deterioration preventing agent, a lubricant, or a reinforcing agent such as carbon black or fiber may be mixed. These waste materials can be used alone or in combination of two or more kinds, or can be used by mixing with other resin or rubber-based waste materials.

In the present invention, the temperature at which shearing force is applied to the vulcanized rubber material is set to 230 ° C. or lower. This is because if the temperature exceeds 230 ° C., a foul odor is generated, and the pulverized waste material is thermally fused. Also,
If the temperature is lower than 80 ° C., the powder cannot be sufficiently pulverized, and the load current of the drive motor of the extruder is significantly increased, which may cause the extruder to stop.

In the present invention, when the waste material made of vulcanized rubber material is supplied to the device for applying a shearing force, the waste material is roughly crushed into a granular material having a predetermined particle diameter by a crusher or the like. This is to prevent the waste material from causing blocking or surging in the charging means of the device for applying the shearing force (for example, a hopper when the device for applying the shearing force is an extruder).
The preferable particle size of the granular material is about 20 mmφ. In addition, pellets such as off-grade products having a particle size of 20 mmφ or less can be used as they are without crushing.

The extruder for applying shearing force to the vulcanized rubber material used in the present invention is a single-screw extruder, a multi-screw extruder or the like used for forming pipes and tubes, covering electric wires, compounding and the like. Can be applied. Especially when finely pulverizing the vulcanized rubber material,
Use a twin-screw extruder because it is possible to specify an appropriate shearing force, and it is possible to stably obtain a pulverized product with a desired particle size for a long time by the scraping (self-cleaning) action generated by mutual screws. Is preferred.

When the waste material made of the rubber material is pulverized as in the present invention, a filler added to the resin,
In particular, if a shearing force is applied after adding a substance classified as an anti-blocking agent such as talc powder, mica powder, zinc stearate powder, etc. to the waste material, it is possible to prevent the rubber-based material from sticking, and the finely divided rubber-based It is possible to prevent the material from aggregating. Therefore, the work of loosening the agglomerated rubber-based material fine powder is not required, which is efficient.

[0013]

In the present invention, shearing force is applied to the waste material made of granular vulcanized rubber material at a temperature of 230 ° C. or lower. By defining the temperature in this way, it is possible to pulverize a sufficiently vulcanized waste material made of a rubber-based material without causing a foul odor, causing no heat fusion.

[0014]

EXAMPLES Examples of the present invention will be specifically described below.

Example 1 Based on polybutadiene rubber and natural rubber, zinc oxide, carbon black, stearic acid, oil, an antioxidant, sulfur as a vulcanizing agent, and N-oxydiethylene-2 as a vulcanization accelerator were used. -145% rubber-based material to which benzothiazole sulfenamide (OBS) was added.
The tire waste material vulcanized at 30 ° C. for 30 minutes was roughly crushed using a crusher to obtain a coarse powder having an average particle size of about 20 mm. Then, the obtained coarse powder has a screw diameter D of 30 mm and a ratio L / D of the screw diameter D to the screw length L of 24.
Was charged into the hopper of the twin-screw extruder. Then, the screw rotation speed was set to 100 rpm, the cylinder temperature was set as shown in Table 1 below, and this coarse powder was fed into the cylinder, and shearing force was applied in the extruder to obtain fine powder of Example 1. In addition, the cylinder temperature was set for each of four regions (regions 1 to 4 starting from the region near the hopper) of the cylinder.

Examples 2 and 3 and Comparative Example 1 Similar to Example 1 except that the cylinder temperatures in the regions 1 to 4 are set as shown in Table 1 below, only a slight difference from Examples 2 and 3 and Comparative Example 1 is performed. A powder was obtained.

[0017]

[Table 1] Example 4 The coarse powder having an average particle size of about 20 mm obtained in Example 1 was put into a hopper of a single-screw extruder having a screw diameter D of 30 mm and a ratio L / D of the screw diameter D to the screw length L of 20. I put it in. After that, set the screw rotation speed to 8
At 0 rpm, the cylinder temperature was set as shown in Table 2 below, this coarse powder was fed into the cylinder, and shearing force was applied in the extruder to obtain fine powder of Example 4. In addition, the cylinder temperature was set for each of four regions (regions 1 to 4 starting from the region near the hopper) of the cylinder.

[0018]

[Table 2] Example 5 Based on nitrile rubber and vinyl chloride, on which zinc oxide, stearic acid, carbon black, plasticizer, alkylphenol resin, antioxidant, wax, sulfur as vulcanizing agent, and N-cyclohexyl as vulcanization accelerator. -2-benzothiazole-sulfanide (CBS)
And tetraethyl thiuram disulphide (TET
The rubber material to which D) was added was vulcanized at 150 ° C. for 20 minutes, and the waste material of the hose was roughly crushed using a crusher to obtain a coarse powder having an average particle size of about 15 mm. Next, the obtained coarse powder was put into a hopper of a twin-screw extruder having a screw diameter D of 44 mm and a ratio L / D of the screw diameter D to the screw length L of 20. After that, change the screw speed to 150.
The crude powder was fed into the cylinder at a rpm of cylinder with the cylinder temperature set as shown in Table 3 below, and a shearing force was applied in the extruder to obtain a fine powder of Example 5. In addition, the cylinder temperature was set for each of four regions (regions 1 to 4 starting from the region near the hopper) of the cylinder.

Examples 6, 7 and Comparative Example 2 Similar to Example 4, except that the cylinder temperatures in the regions 1 to 4 are set as shown in Table 3 below, the results of Examples 6, 7 and Comparative Example 2 are slightly different. A powder was obtained.

[0020]

[Table 3] Example 8 The coarse powder having an average particle size of about 15 mm obtained in Example 5 was put into a hopper of a single-screw extruder having a screw diameter D of 40 mm and a ratio L / D of the screw diameter D to the screw length L of 18. I put it in. After that, change the screw rotation speed to 6
At 0 rpm, the cylinder temperature was set as shown in Table 4 below, this coarse powder was fed into the cylinder, and shearing force was applied in the extruder to obtain fine powder of Example 8. The cylinder temperature was set for each of the three regions (the regions closer to the hopper to the regions 1 to 3) in which the cylinder was divided.

[0021]

[Table 4] Example 9 Ethylene-propylene rubber with zinc oxide, stearic acid,
A rubber material containing calcined clay, carbon black, oil, wax, anti-aging agent, dicumyl peroxide as a crosslinking agent, and dibenzoylquinonedioxime as a vulcanization accelerator is vulcanized at 160 ° C. for 30 minutes. The electric wire coating waste material was roughly crushed using a crusher to obtain a coarse powder having an average particle size of about 25 mm. Next, the obtained coarse powder was put into a hopper of a twin-screw extruder having a screw diameter D of 44 mm and a ratio L / D of the screw diameter D to the screw length L of 20. Then, the screw rotation speed was set to 350 rpm, the cylinder temperature was set as shown in Table 5 below, and this coarse powder was fed into the cylinder, and shearing force was applied in the extruder to obtain fine powder of Example 9. In addition, the cylinder temperature was set for each of four regions (regions 1 to 4 starting from the region near the hopper) of the cylinder.

Examples 10 and 11 and Comparative Example 3 Examples 10 and 1 were carried out in the same manner as Example 9 except that the cylinder temperatures in the regions 1 to 4 were set as shown in Table 5 below.
1. Fine powders of Comparative Example 3 were obtained.

[0023]

[Table 5] Example 12 The coarse powder having an average particle size of about 15 mm obtained in Example 9 was loaded into a hopper of a single-screw extruder having a screw diameter D of 40 mm and a ratio L / D of the screw diameter D to the screw length L of 16. I put it in. After that, change the screw rotation speed to 6
At 0 rpm, the cylinder temperature was set as shown in Table 6 below, this coarse powder was fed into the cylinder, and a shearing force was applied in the extruder to obtain a fine powder of Example 12. The cylinder temperature was set for each of the three divided regions of the cylinder (regions closer to the hopper to regions 1 to 3).

[0024]

[Table 6] With respect to the obtained fine powders of Examples 1 to 12 and Comparative Examples 1 to 3, the odor when discharged from the extruder and the average particle size thereof were measured. The results are shown in Table 7 below. The average particle size was measured by a laser diffraction type particle size distribution measuring device.

[0025]

[Table 7] As is apparent from Table 7, the fine powders (Examples 1 to 12) obtained by the method of the present invention had no offensive odor and did not cause blocking. In particular, fine powder obtained using a twin-screw extruder (Examples 1-3, 5-7, 9-11)
Had a small average particle size. On the other hand, the fine powders (Comparative Examples 1 to 3) obtained under the condition that the set temperature when the shearing force was applied to the coarse powder was 230 ° C. or higher had an offensive odor, and the powders were heat-sealed to each other.

Example 13 The waste material of the tire used in Example 1 was roughly pulverized by using a pulverizer to obtain a coarse powder having an average particle size of about 20 mm. The talc powder was mixed at a ratio of 3 to 10 parts by weight with respect to 100 parts by weight of this coarse powder. Then, the obtained mixture was put into a hopper of a twin-screw extruder having a screw diameter D of 30 mm and a ratio L / D of the screw diameter D to the screw length L of 24. Then, in the same manner as in Example 1, this mixture was fed into a cylinder, and shearing force was applied in the extruder to obtain fine powder. At this time, none of the obtained fine powders aggregated. Therefore, it is not necessary to loosen the fine powder that has become agglomerate due to agglomeration, which is conventionally required, and the fine powder can be efficiently pulverized.

[0027]

Industrial Applicability As described above, the pulverized method of vulcanized rubber material of the present invention pulverizes the waste material into granules and applies a shearing force to the granules. Therefore, the method is simple, efficient and continuous. The waste material of the vulcanized rubber material can be pulverized to obtain powdery fine powder.

According to the present invention, it is possible to meet the demands for resource saving and energy saving imposed on the industry in recent years,
It has extremely industrial value.

Claims (1)

[Claims] 1. A waste material made of granular vulcanized rubber-based material.
A method for atomizing a vulcanized rubber-based material, which comprises applying a shearing force at a temperature of 30 ° C. or lower.