JPH08176341A - Method for powdering - Google Patents

Abstract

PURPOSE: To obtain a powder capable of improving fatigue, heat aging and ozone resistances, etc., of a vulcanized rubber containing the powder blended therein by mixing a p-phenylenediamine derivative with a specific inorganic filler and an inorganic reinforcing agent and powdering the resultant mixture. CONSTITUTION: An N-alkyl-N'-phenyl-p-phenylenediamine derivative of the formula (R is an 8-19C alkyl) which is a liquid or a viscous liquid at ambient temperature is powdered by mixing 100-600wt.% compound of the formula with 100wt.% component comprising solely either of (A) calcium silicate having 45-65% content of SiO2 and 300-600ml/100g volume of oil absorption or (B) basic magnesium carbonate. Otherwise, the compound of the formula is powdered by mixing 100wt.% component which is selected from the components (A) and (B) and further (C) an inorganic reinforcing agent and/or an inorganic filler other than the components (A) and (B) at >=5wt.% blending ratio of the component (A) to 100wt.% component, >=30wt.% blending ratio of the component (B) to 100wt.% component and 0-50wt.% blending ratio of the component (C) to 100wt.% component with 100-600wt.% compound of the formula.

Description

Detailed Description of the Invention

[0001]

[Industrial application] The following general formula [I]

Embedded image The N-alkyl-N′-phenyl-p-phenylenediamine derivative which is liquid or viscous liquid at room temperature represented by [hereinafter, abbreviated as “p-phenylenediamine derivative”]. ] Of the powdering method.

[0002]

2. Description of the Related Art Rubber products are generally composed of raw rubber, higher fatty acids such as stearic acid, metal oxides such as zinc oxide, vulcanizing agents such as sulfur, vulcanization accelerators, vulcanization activators, antioxidants and carbon. A rubber compounding agent such as black or an inorganic filler and / or an inorganic reinforcing agent is kneaded by a mixer such as a roll mill, molded, vulcanized, and finished to obtain a product. Among these compounding agents for rubber, especially for vulcanization accelerators and anti-aging agents that are liquid or viscous liquid at room temperature, it is difficult to measure and kneading when kneading with rubber in a mixer such as a roll mill. Generally, 85% of silicon dioxide is
It is used after being powdered by mixing with the white carbon contained above.

However, in experiments conducted by the inventors, that is, in powdering one component of the p-phenylenediamine derivative and the vulcanization accelerator and antiaging agent which are liquid or viscous liquid at room temperature as described above. White carbon containing 85% or more of commonly used silicon dioxide was mixed at a ratio of 2: 1 to give a powder, and the physical properties of a vulcanized rubber containing 3 phr of this powder were measured. It was found that fatigue resistance, heat aging resistance, and ozone resistance were remarkably inferior in comparison with a vulcanized rubber containing 2 phr of the p-phenylenediamine derivative used for powdering.

From these results, the vulcanized rubber containing the p-phenylenediamine derivative was pulverized by mixing with the inorganic filler and / or the inorganic reinforcing agent at a mixing ratio capable of being pulverized. Powdered p-phenylenediamine derivative without reducing fatigue resistance, shochu heat aging resistance and ozone resistance in comparison with vulcanized rubber containing a considerable amount of p-phenylenediamine derivative before powdering. The method of doing so has not been found yet, and the powdering method is strongly demanded in the rubber industry.

[0005]

A vulcanized rubber prepared by pulverizing a p-phenylenediamine derivative with an inorganic filler and / or an inorganic reinforcing agent at a mixing ratio capable of being pulverized, and blending the powder. The p-phenylenediamine derivative is powdered without reducing fatigue resistance, heat aging resistance and ozone resistance in comparison with a vulcanized rubber containing a considerable amount of the p-phenylenediamine derivative before powdering. It is to provide the art with a method of realizing the above.

[0006]

Means for Solving the Problems The inventors of the present invention have made extensive studies in view of the above problems, and as a result, (1) the content of silicon dioxide is 45.0 to 65.0%,
Calcium silicate having an oil absorption of 300 to 600 ml / 100 g 100 to 5% by weight (2) Basic magnesium carbonate 100 to 30% by weight (3) Inorganic reinforcing agent and / or inorganic filler other than the above (1) and (2) Agent 50 to 0% by weight Component 10 consisting of each of the above (1) and (2) alone or selected from the group of the above (1), (2) and (3)
0 wt% and the following general formula [I]

Embedded image The p-phenylenediamine derivative represented by
The vulcanized rubber mixed with 0% by weight and powdered was surprisingly the same as the vulcanized rubber containing a considerable amount of the p-phenylenediamine derivative used in the powderization. On the other hand, it was found that fatigue resistance, heat aging resistance, ozone resistance and the like are not deteriorated, and the present invention has been completed based on this finding. That is, the feature of the present invention is that the special calcium silicate and /
Alternatively, by using the basic magnesium carbonate or the like described in (2) above as a powdering material of a p-phenylenediamine derivative, fatigue resistance, heat aging resistance, ozone resistance, etc. of a vulcanized rubber compounded with this powder can be obtained. It is a method for producing a powder of a p-phenylenediamine derivative capable of improving the expected effect without adversely affecting the above.

(1) According to the present invention, the content of silicon dioxide is 45.0 to 65.0%, and the oil absorption is 300 to 600.
Examples of the calcium silicate of ml / 100 g include, but are not limited to, Fluorite R and RN manufactured by Tokuyama Corporation and MICRO-CELT-38, E and T-26 manufactured by Johns Manville Co., USA. Further, the component (1) is used alone at 100% by weight, or when the mixing ratio to the component 100% by weight selected from the group of the above (1), (2) and (3) is 5% by weight or more. is there. (2) Basic magnesium carbonate according to the present invention is T, TT manufactured by Tokuyama Corporation or AM-5 manufactured by Asahi Glass Co., Ltd.
0, AM-60, AM-70, AM-80 and AM-9
0, but is not limited thereto.
Further, the component (2) is used alone at 100% by weight, or the mixing ratio to 100% by weight of the component selected from the groups (1), (2) and (3) is 30% by weight or more. If it is less than 30% by weight, it is economically difficult.

(3) Inorganic reinforcing agents and / or inorganic fillers other than the above (1) and (2) according to the present invention include dry method white carbon, wet method white carbon, activated calcium carbonate, magnesium silicate, Hard clay,
Examples thereof include, but are not limited to, calcium carbonate, light calcium carbonate, clay and talc.
Further, the component (3) has a mixing ratio of 50 to 0% by weight to 100% by weight of the component selected from the groups (1), (2) and (3), and the mixing ratio is 50% by weight. If the amount exceeds the above range, it may be difficult to make powder, and it becomes difficult to improve fatigue resistance, heat aging resistance and ozone resistance of the vulcanized rubber containing this powder as expected.

The p-phenylenediamine derivative according to the present invention can be synthesized by a known method.
-(1-Methylheptyl) -N'-phenyl-p-phenylenediamine, N- (1.4-dimethylheptyl)-
N'-phenyl-p-phenylenediamine, N- (1-
Examples thereof include methyldodecyl) -N'-phenyl-p-phenylenediamine and N- (1-methyloctadecyl) -N'-phenyl-p-phenylenediamine.

100 parts by weight of a component consisting of the p-phenylenediamine derivative according to the present invention and the above (1) and (2) alone or selected from the above groups (1), (2) and (3). The mixing ratio with 100% by weight is 100 to 600% by weight, but if the amount is less than 100% by weight, it is economically difficult, and if it exceeds 600% by weight,
Powdering becomes difficult.

100 parts by weight of a component consisting of the p-phenylenediamine derivative according to the present invention and the above (1) and (2) respectively, or selected from the above groups (1), (2) and (3). Examples of the mixing method with% include a method using a mortar and a pestle, a method using a high-speed mixer, and the like, but if the mixing method can achieve the object of the present invention,
It is intended that the invention be covered by the following claims.

The powder of the p-phenylenediamine derivative produced by the powdering method according to the present invention is a natural rubber or a synthetic rubber such as isoprene rubber, styrene butadiene rubber, acrylonitrile butadiene rubber, chloroprene rubber, butyl rubber, It can be used by blending with ethylene propylene rubber or the like, and also with blended rubber of two or more of these. Examples of the present invention are shown below,
The claims of the present invention are not limited to the embodiments of the embodiments.

[0013]

【Example】

Example 1. Powdered N- (1-methylheptyl) which is a viscous liquid at room temperature
Table 1 shows the results of mixing -N'-phenyl-p-phenylenediamine and the inorganic powder shown in Table 1 with a mortar and pestle at room temperature at the mixing ratio shown in Table 1.

[0014]

[Table 1]

Example 2. Properties in Natural Rubber Blends Based on the blends in Table 2, an unvulcanized rubber composition of each sample shown in Table 3 was prepared by a known method using an 8-inch test roll,
Press vulcanization under vulcanization conditions of 150 ° C x 15 minutes, JIS
Five pieces of dumbbell-shaped No. 3 type described in K 6251-1993 (tensile test method for vulcanized rubber) were prepared for each sample. Using these dumbbell-shaped No. 3 type, JI
Elongation of 0 to 1 with a flex crack tester described in SK 6260-1993 (flex crack test method for vulcanized rubber).
The number of elongations until the test piece broke at 00% was measured at room temperature and used as a guideline for fatigue resistance. The results are shown in Table 3 as an average value of 5 test pieces. Further, the unvulcanized rubber composition of each sample described above was vulcanized under the same conditions as described above to prepare a vulcanized rubber composition of each sample, and 13 vulcanized rubber compositions of each sample were prepared.
A piece of 5 × 15 × 2 mm tanzaque test piece was punched out,
An ozone test was conducted under the conditions of test temperature: 40 ° C., ozone concentration: 50 pphm, elongation rate: 50%, test time: 72 hours, and then using the vulcanized rubber composition of each sample, JI
Air heating aging test (aging condition: 80 ° C x) according to SK 6257-1993 (vulcanized rubber aging test method)
The test piece: dumbbell-shaped No. 3 type) was performed for 240 hours, and the results are shown in Table 3.

[0016]

[Table 2]

[0017]

[Table 3]

Example 3. Properties with Chloroprene Rubber Blends Based on the blends in Table 4, an unvulcanized rubber composition of each sample shown in Table 5 was prepared by a known method using an 8-inch test roll,
Press vulcanization under vulcanization conditions of 150 ° C x 30 minutes, JIS
Five pieces of dumbbell-shaped No. 3 described in K 6251-1993 (tensile test method for vulcanized rubber) were prepared for each sample. Using these dumbbell-shaped No. 3 type, JI
Elongation of 0 to 1 with a flex crack tester described in SK 6260-1993 (flex crack test method for vulcanized rubber).
The number of elongations until the test piece broke at 00% was measured at room temperature and used as a guideline for fatigue resistance. The results are shown in Table 5 as an average value of 5 test pieces.

[0019]

[Table 4]

[0020]

[Table 5]

Example 4. Properties of Styrene Butadiene Rubber Blends Based on the blends of Table 6, unvulcanized rubber compositions of each sample shown in Table 7 were prepared by a known method using an 8-inch test roll,
Press vulcanization was performed under vulcanization conditions of 150 ° C. for 30 minutes to prepare a 135 × 15 × 2 mm tanzaque test piece for each sample, the test temperature was 40 ° C., the ozone concentration was 50 pphm,
An ozone test was conducted under the conditions of elongation rate: 20% and test time: 12 hours, and the results are shown in Table 7.

[0022]

[Table 6]

[0023]

[Table 7]

[0024]

EFFECT OF THE INVENTION In Table 1, even white carbon containing 85% or more of silicon dioxide, which is generally used for pulverizing vulcanization accelerators and anti-aging agents which are liquid or viscous liquid at room temperature, has a viscosity at room temperature. It is possible to powder N- (1-methylheptyl) -N'-phenyl-p-phenylenediamine, which is a serum, in this Comparative Example [Comparative Examples 5, 7 and 9].
From the results of Table 3, Table 5 and Table 7, the fatigue resistance, the heat aging resistance and the fatigue resistance, the heat aging resistance and It is clear that ozone resistance is significantly reduced.

In Table 1, N- (1-methylheptyl) -N'- which is a viscous liquid at room temperature in each Example of the present invention.
Phenyl-p-phenylenediamine can be powdered, and the results of Table 3, Table 5 and Table 7 show that the examples of the present invention are N-
In comparison with a sample containing the same amount of (1-methylheptyl) -N'-phenyl-p-phenylenediamine, fatigue resistance, heat aging resistance and ozone resistance show almost the same effect, and there is no adverse effect. It is clear.

In the examples of the present invention, (1) the content of silicon dioxide is 45.0 to 65.0%, and the oil absorption is 300 to 60.
Powder mixture of 0 ml / 100 g of calcium silicate, (2) basic magnesium carbonate and a mixture of inorganic reinforcing agents and / or inorganic fillers other than the above (1) and (2) [Invention Examples 8 and 13, 18, 23] is included, the possibility of reducing the manufacturing cost of N- (1-methylheptyl) -N′-phenyl-p-phenylenediamine powder according to the present invention, which is a viscous liquid at room temperature. Can be considered.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yoshiko Yamamoto 7-4 Oofune, Kobunecho, Nihonbashi, Chuo-ku, Tokyo Inside Shinko Chemical Industry Co., Ltd.

Claims (1)

[Claims] (1) Content of silicon dioxide 45.0 to 6
5.0% and oil absorption 300-600ml / 100g
Calcium silicate 100 to 5% by weight (2) basic magnesium carbonate 100 to 30% by weight (3) inorganic reinforcing agent and / or inorganic filler other than the above (1) and (2) 50 to 0% by weight above ( Component 10 consisting of 1) and (2) each alone or selected from the group of (1), (2) and (3) above.
0 wt% and the following general formula [I] Represented by the above general formula [I], which is characterized by being mixed with 100 to 600% by weight of the N-alkyl-N'-phenyl-p-phenylenediamine derivative which is liquid or viscous at room temperature. A method for powderizing an N-alkyl-N'-phenyl-p-phenylenediamine derivative which is liquid or viscous at room temperature.