JPS588546A - Preparation of granular org. rubber chemicals - Google Patents

Abstract

PURPOSE:To obtain a particulate material which has a uniform spherical shape with no dust scatterimg property and excellent fluidity, by stirring and granulating the heated melt of org. rubber chemicals by using the powder of org. rubber chemicals same to said melt as a granulating assistant. CONSTITUTION:In preparing the granular substance of org. rubber chemicals solid at a room temp., as a granulating aid, the powder of org. rubber chemicals same to the heated melt of org. rubber chemicals is used and granulation is carried out under stirring in water to which the ganulating aid is added. By preparing the granular substance as referred above, the granular substance, which does not scatter as dust during handling, with excellent fluidity while losing no dispersing property to rubber and deteriorating no properties as rubber chemicals, is obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing coarse-grained organic rubber chemicals, and more specifically, the invention involves stirring and granulating organic rubber chemicals heated and melted in water containing a specific granulation aid. This invention relates to a new method for producing granular organic rubber chemicals that have a nearly uniform spherical shape, do not scatter dust, and have good fluidity.

Organic chemicals that are solid at room temperature, such as 2-(morpholinothio)-benzothiazole (hereinafter abbreviated as MTBT), are commercially available in large quantities as vulcanization accelerators for rubber, usually in the form of flakes or pellets. used in However, in these forms, part of the shape may be lost or collapsed during handling such as transportation and weighing, resulting in insufficient fluidity due to the generated fragments and powder, which can be a problem when continuously using a fixed amount. This not only causes problems, but also causes the generated powder to scatter, which is unfavorable from the standpoint of environmental hygiene.

The purpose of the present invention is to improve the disadvantages of the shape of conventional organic rubber chemicals, and to provide a method for producing and using granules that does not impair the dispersibility in rubber and the performance as rubber chemicals in practice. In particular, there is a known method of granulating a heated melt of OMTBT in water using a solvent (Japanese Patent Publication No. 1973-
15264, etc.), if a solvent is used, a process to recover it and a process to treat the solvent in the waste water is required, which not only complicates the process but also partially evaporates the solvent. Unfavorable for work environment. In addition, when the heated molten material is simply stirred and granulated in water using a known method, the shape cannot be made uniform as described in the comparative example below, and furthermore, the granulation tank wall It is undesirable to adhere to such surfaces as it may cause problems in the process.

Furthermore, a method has been proposed in which organic rubber chemicals are granulated in solid powder form by heating and stirring in water (see Japanese Patent Laid-Open No. 54-62245, etc.), but the entire amount of granulation raw material is pulverized into fine powder. Difficulties such as having to do the following are recognized.

As a result of intensive research to improve the shortcomings of conventional methods for granulating organic rubber chemicals, the inventors of the present invention have found that they do not scatter dust during handling, have good fluidity, and are easily dispersible into rubber. And, it has been possible to obtain granules that do not impair their performance as rubber chemicals.

That is, in producing granules of bonded rubber chemicals that are solid at room temperature, the present invention involves using a heated melt of the organic rubber chemicals as a granulation agent with a powder of the same organic rubber chemicals as the melt. The present invention provides a new method for producing granular organic rubber chemicals, which is characterized by stirring and granulating in water added as an agent.

Hereinafter, the present invention will be explained using MTBT as a representative example of organic rubber chemicals.

As the granulation aid (hereinafter abbreviated as core) of the present invention, a pulverized solid of MTBT is used.

The particle size of the nucleus should be α511O11 or less, and Ql~α
Approximately 8 teachers is preferable. There is no particular need to make it into a fine powder. The amount of nuclei supplied varies depending on the thickness of the target particles, and is preferably 06 to 80 parts by weight, preferably 5 to 20 parts by weight, based on the solik portion of the heated melt.

Granules of any size can be obtained depending on the supply of the core, the temperature of the water in the tank, and stirring conditions.

Since MTBT powder is used as the core, loose impurities are not mixed in. MTBT is usually 80℃
Although having the above point, in the present invention, MTBT heated and melted to about 8.6° C. or higher is added to the water in the granulation tank.

Alternatively, heat and melt MTBT to about 86°C or higher and add it to water prepared separately in advance to make a molten dispersion of MTBT (temperature maintained at 80 to 85°C), and add this dispersion to the water in the granulation tank. May be added to. The granulation temperature of water in the granulation tank is preferably 70'C or less, preferably 40 to 66C. When the temperature exceeds 70'C, the added or formed nuclei become semi-molten, and even if a melt of MTBT is added, they are not granulated instantly. Furthermore, if granulation is carried out at a temperature below 40°C, the particle size will become irregular, which is not preferable.

The method of the present invention can be either a batch method or a continuous method, but -
In the case of a continuous type, it is possible to supply a certain number of violet nuclei into the granulation tank, and then generate the violet nuclei by stirring the tank without supplying the violet P, making it possible to generate new violet nuclei. It is advantageous because there is no need to add granules to the surface and granulation is instantaneous due to the presence of the nuclei.

The size of the 1MTPT particles obtained in the present invention can be freely changed depending on the type of stirring, stirring speed, amount of nuclei added, and granulation temperature, but a size of approximately Q1 to 8 dew is generally preferred for practical purposes.

Although the above explanation was made using MTBT as a representative example, the present invention can be applied to a method for producing granular forms of other organic rubber chemicals that are solid at room temperature. For example, as a vulcanization accelerator,
Thiazoles such as N-cyclohexyl-2-benzothiazolesulfenami) 11°2-(4-'morpholinyldithio)benzothiazole, diethylthiourea.

Thioureas such as dibutylthiourea, anti-aging agents include N-isopropyl-N'-phenyl-P-phenylenediamine, 1l-(1,8-dimethylbutyl)
It is applicable to P-'phenylenediamine derivatives such as -N/-phenyl-P-phenylenediamine and mixed sialyl-P-phenylenediamine.

The present invention will be explained in more detail below with reference to Examples, Comparative Examples, and Test Tuna Examples, but the present invention is not limited thereto.

Example 1 In a 51 beaker, 2480 ml of water and a core [particle size 01 to α] were added.
am powder M'l'BT = accelerator N 8") crushed product 3
66 parts by weight, and while stirring at high speed, the water temperature was raised to 58-6.
665 parts of MTBT (Accel NS: melting point 81-866°C) heated and melted at 0°C was added to 847 parts by weight of water.
A solution dispersed at 6°C with stirring was added over 15 minutes, immediately cooled, and dried at 56°C to obtain 618 parts by weight of granules. Its melting point is 81~
The temperature was 865°C. The particle size distribution ratio of the obtained target product was measured using a wire mesh sieve, and the results were as shown in Table 1.

The size of the granules is Q84-L68. The particle size distribution ratio of the range plow was 87%. (Butt 1 is manufactured by Kawaguchi Kagaku Kogyo Co., Ltd.) Example 2 The procedure of Example 1 was followed except that the amount of core added was 90 parts by weight, and 662 parts by weight of granules were obtained. Its melting point was 81-865°C. The particle size distribution ratio of the target product thus obtained was measured in the same manner as in Actual pAi Example 1, and the results are shown in Table 2.

The particle size distribution ratio of the granules in Table 2 whose size ranged from 06 to 1-ow was 78 inches.

Example 8 Example 1 was followed except that the stirring was changed to strong stirring, and 619 parts by weight of granules were obtained. Its melting point is 81~
It was 5°C at 8am. Table 8 shows the results when the particle size distribution ratio of the target product obtained here was the same as in Example 1.

The particle size distribution ratio of the granulated granules having a size in the range of 5 to 68 m was 9.4%.Example 4 Same as Example 1 except that the granulation water temperature was kept at 46 to 47°C. When this was carried out, 619 parts by weight of Ichiya Autumn was obtained. Its melting point was 81-866°C. The target particle size distribution ratio obtained here was measured in the same manner as in Example i, and the results were as shown in Table 4.

The distribution rate of the granules in the size range α52168 am was 82%.

Example 5 Add 42 parts by weight of water and t6 core to 1001 steel/res production grains.
Add parts by weight and stir at high speed until the water temperature is 58-60℃.
to hold. Next, 14.5 parts by weight of MTBT (Accel NS melting point 81-855°C), which had been heated and melted in advance, was added to 2 parts of water.
2 parts by weight of the dispersion (maintained at 85° C.) is added over 20 minutes while stirring. Subsequently, a heat-molten aqueous dispersion of MTBT having the same porosity as above was fed into the granulation tank at a rate of 95 parts per hour. On the other hand, water at 55-60℃ is heated to 108℃.
Supplied into the granulation tank at a rate of 58 to 60
Keep at ℃.

Note that new nuclei will not be supplied from outside. A part of the granules once granulated by the agitator in the granulation tank have a particle size of 0.85mm.
Grind into small granules as follows:

Use this as the core. The granulated slurry thus produced was taken out at 2175 parts by weight/hour, cooled, filtered,
When drying was carried out at 55°C, the melting points of the granules collected after 805) and 1 hour were both 81-8&5°C. The particle size distribution ratio of the obtained target product was measured using a wire mesh sieve, and the results are shown in Table 6.

The particle size distribution of the granules in Table 5 whose size ranged from α5 to 168 m was 86% both after 80 minutes and after 1 hour.

Comparative Example 1 The procedure of Example 1 was followed except that no nuclei were added.
418 parts by weight of granules were obtained.

Its melting point was 81-856°C. The amount of ungranulated MTBT deposited on the stirring rod and beaker was 1501 parts by weight. The particle size distribution ratio of the target product obtained here is shown in Example 1.
The results measured in the same manner as in Table 6 were as shown in Table 6.

The particle size distribution ratio of the granules in Table 6 having a size of 168 cm or more was 98 cm.

Test Example V 1 Comparison test of the angle of repose and disintegration rate between the granular product of the present invention and the flake product The angle of repose and A disintegration rate comparison test was conducted. The results are shown in Table 7.

Table 7 (412): Accel NS (manufactured by Kawaguchi Chemical Industry Co., Ltd.) (Ao8
) Two-repose angle measurement method "Granulation Handbook" edited by Japan Powder Industry Association (Ohmsha 5α680
Published) Page 48 2.6.1 Measurement method of angle of repose CB) Measured according to the infusion sword method.

(Scale 4): Disintegration rate test method Sample 109 was shaken for 80 minutes using a TS type shaker (manufactured by Irie Shokai) using a 42 mesh sieve.The amount of the amount that passed through the 42 mesh sieve before shaking (percentage of 10! is the decay rate.

The test results in Table 7 indicate that the granular product of the present invention has better fluidity than flake products and is a granular product that is difficult to disintegrate.

Test Example 2 Dispersibility test of the granular product of the present invention in rubber A laboratory plasto mill (connection 5) was heated to 70°C and a synthetic rubber BRO process (connection 6
), and while rotating at 10 rpm, the granular product of Example 2 of the present invention or the comparative sample (Accel N S
) (+7) was added at 05 phr each and rotated for 60 seconds to conduct a comparative test for dispersibility in the rubber. As a result, the granular product of Example 2 of the present invention was completely dispersed in the rubber in 60 seconds, and no particles were found even when observed using a microscope with a magnification of 20 times, and the dispersibility was comparable to that of the flake product. They were exactly the same.

(Kaoru 5): Newly manufactured by Toyo Seiki Seisakusho (sanshu 6) - Manufactured by Japan Synthetic Rubber Co., Ltd. [ML, +4 (100℃)
) 44] (+7): Kawaguchi Chemical Industry Co., Ltd. flake product test example 3 Vulcanization performance test of granular products of the present invention Based on the formulation table in Table 8, the roll formulation was J-5K6800.
The performance test of the vulcanized rubber was conducted in accordance with K2SO3 from J. The results are shown in Table 9.

No. 8 Coated Natural Rubber (SMR-5) 100 Heavy Ichibukyo Zinc (No. 1: manufactured by Mitsui Kinzoku Kogyo Co., Ltd.) 5 Stearic Acid (manufactured by Nippon Oil & Fats Co., Ltd.) 8) iAF (Geest≠
82 (manufactured by Tokai Carbon Co., Ltd.) 50 Process oil (Nnishiku process oil R-2001 omt part; manufactured by Kyodo Oil Co., Ltd.) Sulfur (colloidal sulfur: manufactured by Hosoi Chemical Industry Co., Ltd.) 2-5 Test vulcanization accelerator o8 No. 9
The test results in Table 9 show that the granular product of the present invention was vulcanized once (t
5 + t31 hours), indicating that the physical properties of the vulcanizate are comparable to flake products.

Patent applicant: Kawaguchi Chemical Industry Co., Ltd.

Claims (1)

[Scope of Claims] L In order to produce granules of organic rubber chemicals that are solid at room temperature, a heated melt of the organic rubber chemicals is transformed into a powder of the same organic rubber chemicals as the melt. A method for producing granular organic rubber chemicals, characterized by stirring and granulating in water to which rubber is added as a granulation aid. 2' The manufacturing method according to claim 1, wherein the particle size of the granulation aid made of powder is α5a or less. The manufacturing method according to claim 1, wherein 100 parts by weight of the heated melt and 5 to 80 parts by weight of a granulation aid α consisting of powder are added to the water.