JPS5891739A - Deodorized sulfonamide additive for rubber - Google Patents

Abstract

PURPOSE:To provide the titled additive of which the odor is improved to a large extent, prepared by incorporating an amine compound or a fine inorg. filler for a rubber compound in a specific sulfonamide compound. CONSTITUTION:A rubber additive contains (A) a sulfonamide compound shown by formula (wherein R1 and R2 are each 1-12C alkyl, cycloalkyl or aryl) (e.g., N-isopropylthio-N-cyclohexyl benzothiazole-2-sulfonamide) and (B) an amine compound (e.g., triisopropanolamine) or a fine inorg. filler for a rubber compound (e.g., CaCO3 with an average particle size of 0.1mu or less treated with an org. acid). By compounding component B in component A which has an excellent vulcanization retarding effect but is hardly used because of the peculiar odor thereof, the ordor is improved to a large extent.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to additives for rubber. More particularly, the present invention relates to deodorized rubber additives.

In recent years, in the rubber industry, as factory environments have changed and safety (1) hygiene requirements have increased, strict regulations have been put in place regarding the odor of compounding agents in rubber.

On the other hand, as rubber products such as tires and belts become larger and production efficiency improves, the unvulcanized rubber compound
Due to the harsher thermal history, there is a great social demand for better vulcanization retarders.

The present inventors have investigated the deodorization of sulfonamide-based rubber additives, which have an excellent vulcanization retardation effect but are difficult to use due to their unique odor.
It was discovered that the odor can be greatly improved by adding an amine compound@ or an inorganic filler for rubber compounding to it, leading to the completion of the present invention.

That is, the present invention provides (1) a sulfonamide compound 1 represented by the following formula (2) (wherein K and R2 each represent C-C, an alkyl group, a cycloalkyl group, or an aryl group)
, and (2) a rubber additive containing an amine compound or a fine inorganic filler for rubber compounding.

In the above formula, the alkyl group represented by k and R2 includes, for example, methyl, ethyl, propyl, butyl, amyl, hexyl, heptinopeoctyl, noni/L/, decyl, dodecyl isomers, etc. Examples of the cycloalkyl group include cyclopentyl and cyclohexyl, and examples of the aryl group include phenyl, tolyl, xylyl, and naphthyl.

As the sulfonamide compound represented by the above formula,
N-methylthio-N-tert-butylbenzothiazole-2-sulfonamide, N-isopropylthio-
N-sec-butylbenzothiazole-2-sulfonamide, N-tert-butylthio-N-tert-butylbenzothiazole-2-sulfonamide, N-Schiff (3) hexylthio-N-tert-butylbenzothiazole- 2-Sulfonamide, N-phenylthio-N-
tert-Butylbenzothiazole-2-sulfonamide, N-xylylthio-N-1ert-butylbenzothiazole-2-sulfonamide, N-isopropylthio-N-cyclohexylbenzothiazole-2-
Sulfonamide N 5ec-butyl-N-cyclohexylbenzothiazole-2-sulfonamide, N
-tert -Octylthio-N-cyclohexylbenzothiazole-2-sulfonamide, N-decylthio-N-cyclohexylbenzothiazole-2-sulfonamide, N-isopropyl-N-phenylbenzothiazole-2-sulfonamide, N -tert- Butylthio N-phenylbenzothiazole-2-sulfonamide, N-tert-octyl-N-phenylbenzothiazole-2-sulfonamide, N-dodecylthio-N-phenylbenzothiazole-2-sulfonamide, N-cyclo(4) Examples include hexyl-N-phenylbenzothiazole-2-sulfonamide and N-phenylthio-N-phenylbenzothiazole-2-sulfonamide.

The amine compounds used in the present invention are fatty amines, alicyclic amines, aromatic amines, and alkanolamines. Specifically, aliphatic amines include trimethylamine, diethylamine, triethylamine, monopropylamine, dipropylamine, tripropylamine, monobutylamine, dibutylamine, tributylamine, monooctylamine, dioctylamine, trioctylamine, monostearylamine. , distearylamine, tristearinamine, etc., as alicyclic amines, monocyclohexylamine, dicyclohexylamine, mono(dimethylcyclohexyl)amine, etc. as aromatic amines, aniline, cytosylamine, etc. Each isomer such as phenylamine, toluidine, xylidine, alkanol (5) amine, trimethanolamine, monoethanolamine, jetanolamine, triethanolamine,
Examples include isomers such as monopropatolamine, dibrobanolamine, tripropanolamine, monobutanolamine, jetanolamine, and tributanolamine. Among these amine compounds, alkanolamines are preferably used.

In addition, examples of the fine inorganic filler for rubber compounding used in the present invention include silica, clay, calcium carbonate, titanium oxide, talc, diatomaceous earth, etc.
Lucium carbonate, particularly calcium carbonate having an average particle size of 0.1 i:m or less and treated with an organic acid, is preferred.

The amine compound is usually added in an amount of 0.1 to 20% by weight based on the sulfonamide compound represented by the above formula.

If the amount added is less than 0.1% by weight, the deodorizing effect will not be sufficient,
Moreover, if it exceeds 20% by weight, it tends to suppress the vulcanization retardation effect (6) of the sulfonamide compound, which is not preferable. Further, the fine inorganic filler for rubber compounding is added in an amount of 5 parts by weight or more, usually 5 to 200 parts by weight, per 10 parts by weight of the sulfonamide compound.

The sulfonamide compound and the amine compound or the fine inorganic filler for rubber compounding may be mixed by any conventional method, but for example, the phosphorus compound is dissolved in a suitable solvent and mixed uniformly, and then the solvent is mixed. This is carried out by removing by distillation or the like, or by mechanically uniformly mixing using a mixer or the like.

The additive of the present invention obtained in this manner is substantially deodorized without impairing the original performance of the sulfonamide compound represented by the above formula, and is advantageous for rubber applications without odor problems. used for.

The present invention will be explained in more detail below with reference to Examples.

Example 1 N-iso(7) propylthio-N-cyclohexylbenzothiazole- as a sulfonamide compound
After dissolving 10 parts of 2-sulfonamide in 50 parts of acetone, 12 parts of triisopropanolamine was added,
After uniformly mixing, acetone was distilled under reduced pressure using a conventional method.

The sulfonamide compounds before and after the addition of triisopropanolamine were placed in sealed 100-g polyethylene bottles and left at 40° C. for 30 minutes. Thereafter, the air in the bottle was put into a polyethylene bag with a zipper and diluted with clean air using a syringe. The dilution rate up to a concentration at which no odor was detected was defined as the odor index.

Table 1 shows the odor index when other sulfonamide compounds 10f and amine compounds shown in Table 1 were mixed in the same proportions as shown in Table 1 using the same method.

(8) Example 2 N-isopropyl 1,000 N-cyclohexylbenzothiazole-2-sulfonamide 10 was added as a sulfonamide compound to a tabletop mixer (Model 5DM) manufactured by Shinjo Kogyo Co., Ltd.
01'O and Neolite S (fatty acid treated calcium carbonate, average particle size 0°04μ = Takehara Chemical brand name) 200 F
and stirred and mixed at a rotational speed of 50 rpm for 10 minutes.

The above sulfonamide compound 109 and the mixture 302 obtained above were each placed in a sealed 100-g polyethylene bottle, left at 40°C for 30 minutes, and then the air inside the bottle was removed with a syringe to remove clean air. The odor index was determined by the dilution ratio at which the odor was no longer felt. In the same manner, other sulfonamide compounds shown in Table ↓ were mixed with fine inorganic fillers for rubber compounding, and similar tests were conducted.

Claims (2)

[Claims] (1) Sulfonamide compound 1 represented by the following formula (in the formula, K and R2 each represent a C to C di-alkyl group, a cycloalkyl group, or an aryl group),
and (2) Rubber additive containing an amine compound or a fine inorganic filler for rubber compounding