KR101642744B1 - Rubber composition for preventing electrostatic discharge of side wall - Google Patents

Abstract

The present invention relates to an antistatic sidewall rubber composition containing a silane-modified polythiophene as a conductive polymer and capable of preventing the generation of static electricity in a tire sidewall portion having a low rotational resistance performance. The present invention relates to an antistatic sidewall rubber composition The electric conductivity is lowered while maintaining the low rotational resistance performance, and the static electricity generated during the rotation of the tire during driving is continuously discharged to the road surface, so that the generation of static electricity can be prevented.

Description

[0001] The present invention relates to an antistatic sidewall rubber composition,

More particularly, the present invention relates to a rubber composition containing a silane-modified polythiophene as a conductive polymer and capable of preventing generation of static electricity in a tire sidewall portion having a low rotation resistance .

Carbon black has been used as a reinforcing filler in order to improve the fuel-efficient performance of a tire side compound among additives used in a sidewall compound for environmentally friendly tires, and carbon black having a grade of 500 to 600 is generally used.

In order to improve the fuel consumption performance, the amount of the carbon black used is reduced, and the carbon black having a grade of 600 or more is not sufficiently realized in reality. Therefore, carbon black 30 having a grade of 500 to 600 To 60 parts by weight.

However, in order to discharge the static electricity generated when the tire rotates, a small amount of electrically conductive carbon black is used, and static electricity is generated.

As an attempt to solve the above-mentioned problem of generation of static electricity, there has been disclosed a rubber composition for a tire to which a hydroxy-modified polythiophene as a conductive polymer is applied (Korean Patent Laid-open No. 10-2011-0073055), the hydroxy- Has a limitation in suppressing the generation of static electricity due to the chemical nature of the hydroxyl group (OH ^- ).

SUMMARY OF THE INVENTION The present invention has been conceived to solve the problems of the conventional art as described above, and it is an object of the present invention to provide a method and apparatus for continuously discharging static electricity generated on rotation of a tire during traveling, Which is capable of solving the problem of generation of static electricity.

In order to achieve the above object, the present invention provides an antistatic sidewall rubber composition comprising 5 to 15 parts by weight of a silane-modified polythiophene based on 100 parts by weight of a raw rubber.

The present invention also provides a tire comprising the rubber composition.

According to the present invention, there is provided an antistatic sidewall rubber composition capable of preventing the generation of static electricity by continuously discharging static electricity generated when the tire rotates while the electric conductivity is lowered while maintaining low rotational resistance performance .

The present invention provides an antistatic sidewall rubber composition comprising 5 to 15 parts by weight of a silane-modified polythiophene based on 100 parts by weight of a raw rubber.

In the antistatic sidewall rubber composition of the present invention, the silane-modified polythiophene may have a silane bonded to the surface of the modified polythiophene by plasma treatment or acid treatment.

In the antistatic sidewall rubber composition of the present invention, the silane may be 3-aminopropyltriethoxysilane or 3-mercaptopropyltriethoxysilane compound, But is not limited thereto.

The antistatic sidewall rubber composition of the present invention may further comprise 30 to 60 parts by weight of carbon black per 100 parts by weight of the raw rubber. The carbon black preferably has a grade of 500 to 600.

In the antistatic side wall rubber composition of the present invention, the raw rubber may be any material as long as it can be used as a raw rubber in a conventional tire rubber composition.

The raw rubber may be a natural rubber alone.

The synthetic rubber may be used alone as the raw material rubber.

The raw rubber may be a mixed rubber in which natural rubber and synthetic rubber are mixed.

The raw rubber may be a mixed rubber in which the natural rubber and the synthetic rubber are mixed in a weight ratio of 5: 95: 5 to 95.

The synthetic rubber may be at least one selected from the group consisting of styrene butadiene rubber (SBR), modified styrene butadiene rubber, butadiene rubber (BR), modified butadiene rubber, chlorosulfonated polyethylene rubber, epichlorohydrin rubber, fluorine rubber, silicone rubber, Butadiene rubber, nitrile rubber, nitrile butadiene rubber (NBR), modified nitrile butadiene rubber, chlorinated polyethylene rubber, styrene ethylene butylene styrene (SEBS) rubber, ethylene propylene rubber, ethylene propylene diene (EPDM) rubber, Butadiene rubber, maleic acid styrene butadiene rubber, epoxy styrene butadiene rubber, epoxy isoprene rubber, maleic acid ethylene propylene rubber, carboxymethyl styrene butadiene rubber, acrylonitrile butadiene rubber, acrylonitrile butadiene rubber, acrylonitrile butadiene rubber, acrylonitrile butadiene rubber, ethylene vinyl acetat rub, acryl rubber, hydrin rubber, vinyl benzyl chloride styrene butadiene rubber, Bicarboxylic acid nitrile butadiene rubber and BIMS (brominated polyisobutyl isoprene e-co-paramethyl styrene) may be used.

The antistatic sidewall rubber composition of the present invention may contain, in addition to the components described above, other vulcanizing agents, stearic acid, vulcanization accelerators, vulcanization accelerators, oils, curing resins, waxes, Can be compounded.

As the vulcanizing agent, it is possible to use an organic peroxide or a sulfur vulcanizing agent. Examples of the organic peroxide include benzoyl peroxide, dicumyl peroxide, di-t-butyl peroxide, t-butyl cumyl peroxide, methyl Dimethyl-2,5-di (t-butylperoxy) hexane, 2,5-dimethyl-2,5-di (benzoylperoxy) hexane, 2, (T-butylperoxy) benzene, di-t-butylperoxy-diisopropylbenzene, t- Butyl peroxybenzene, 2,4-dichlorobenzoyl peroxide, 1,1-di-t-butylperoxy-3,3,5-trimethylsiloxane, n-butyl- Valerate and the like can be used. Of these, dicumyl peroxide, t-butylperoxybenzene and di-t-butylperoxy-diisopropylbenzene are preferable. As the sulfur vulcanizing agent, for example, sulfur, morpholine disulfide and the like can be used. Of these, sulfur is preferable. These vulcanizing agents may be used alone or in combination of two or more.

Examples of the vulcanization accelerator include vulcanization accelerators such as sulfenamide, thiazole, thiuram, thiourea, guanidine, dithiocarbamate, aldehyde-amine or aldehyde-ammonia, imidazoline, It is possible to use one containing at least one of the promoters. Examples of the sulfenamide system include CBS (N-cyclohexyl-2-benzothiazylsulfenamide), TBBS (N-tert-butyl-2-benzothiazylsulfenamide), N, N-dicyclohexyl- Sulfinamide compounds such as thiazyl sulfenamide, N-oxydiethylene-2-benzothiazyl sulfenamide and N, N-diisopropyl-2-benzothiazole sulfenamide. Examples of the thiazole system include sodium salts, zinc salts, copper salts, cyclohexylamine salts, 2- ((2-mercaptobenzothiazole), 2-mercaptobenzothiazole Thiazole-based compounds such as 2,4-dinitrophenyl) mercaptobenzothiazole and 2- (2,6-diethyl-4-morpholinothio) benzothiazole can be used.

As the thiuram series, there may be mentioned, for example, TMTD (tetramethylthiuram disulfide), tetraethylthiuram disulfide, tetramethylthiuram monosulfide, dipentamethylenethiuram disulfide, dipentamethylenethiuram monosulfide, dipentamethylenethiuramtetra Thiuram-based compounds such as sulfide, dipentamethylenethiuram hexasulfide, tetrabutylthiuram disulfide, and pentamethylenethiuram tetrasulfide can be used.

Examples of the thiourea compound include thiourea compounds such as thiacarbamide, diethyl thiourea, dibutyl thiourea, trimethyl thiourea, and diorthotolyl thiourea.

Examples of the guanidine system include guanidine compounds such as diphenyl guanidine, diorthotolyl guanidine, triphenyl guanidine, orthotolyl biguanide, and diphenyl guanidine phthalate.

Examples of the dithiocarbamic acid system include zinc ethylphenyldithiocarbamate, zinc butylphenyldithiocarbamate, sodium dimethyldithiocarbamate, zinc dimethyldithiocarbamate, diethyldithiocarbamate Zinc, zinc dibutyldithiocarbamate, zinc diamidithiocarbamate, zinc dipropyldithiocarbamate, complex salt of zinc and piperidine dicarboxylate, hexadecyl (or octadecyl ) Zinc isopropyldithiocarbamate, zinc dibenzyldithiocarbamate, sodium diethyldithiocarbamate, piperidine pentamethylene dithiocarbamate, selenium dimethyldithiocarbamate, diethyldithiocarbamate, Dithiocarbamate-based compounds such as tellurium oxcarbamate and cadmium diadimethyldithiocarbamate, and the like can be used.

Examples of the aldehyde-amine type or aldehyde-ammonia type include aldehyde-amine type or aldehyde-ammonia type compounds such as acetaldehyde-aniline reactant, butylaldehyde-aniline condensate, hexamethylenetetramine and acetaldehyde- Can be used.

As the imidazoline-based compound, for example, an imidazoline-based compound such as 2-mercaptoimidazoline can be used. As the xanthate-based compound, for example, a xanthate-based compound such as zinc dibutylxanthogenate can be used .

As the vulcanization accelerating assistant, for example, zinc oxide, stearic acid and the like can be used.

As the oil, a process oil, a vegetable oil, a mixture thereof and the like can be mentioned. As the process oil, paraffinic process oil, naphthenic process oil, aromatic process oil and the like can be mentioned. The vegetable oils include vegetable oils such as castor oil, cottonseed oil, linseed oil, rapeseed oil, soybean oil, palm oil, palm oil, peanut oil, pine oil, pine tar, tall oil, Milk, milk, yam, macadamia nut oil, safflower oil, tung oil and the like.

These vulcanization accelerators may be used alone or in combination of two or more.

The present invention also provides a tire comprising the antistatic sidewall rubber composition.

The tire of the present invention is produced by a conventionally known method using the side wall rubber composition. That is, the sidewall rubber composition containing the above-described essential components and other compounding agents as required is kneaded and extruded in accordance with the shape of the sidewall rubber of the tire at the stage of unvulcanization, Together, they are molded on a tire molding machine by a conventional method to form an unvulcanized tire.

By heating and pressing the unvulcanized tire in a vulcanizer, the tire of the present invention can be obtained.

Hereinafter, the present invention will be described with reference to the following Production Examples, Examples and Experimental Examples, but the scope of the present invention is not limited thereto.

PREPARATION EXAMPLE 1 Preparation of silane-modified polythiophene (1).

The surface of the polythiophene was modified by treating the polythiophene with plasma. At this time, plasma treatment was performed for 10 minutes using Quorum PT 7160 under the conditions of argon, air, and RF power of 100W.

40 g of the surface-modified polythiophene and 1 ml of 3-aminopropyltriethoxysilane were reacted at 25 ° C. for 4 hours in a mixed solution containing ethanol and water at a ratio of 80:20 (v / v) Only a precipitated portion was obtained by a separator, followed by vacuum drying to prepare a silane-modified polythiophene.

Preparation Example 2 Preparation of silane-modified polythiophene (2)

The polythiophene was treated with an acid to modify the surface of the polythiophene. At this time, acid treatment conditions were as follows: polythiophene was immersed in strong acid mixed with sulfuric acid: nitric acid in a volume ratio of 3: 1 for 3 hours to partially oxidize, mixed with methanol, distilled water and acetone in a volume ratio of 1: Washed with a solution, and vacuum-dried at 25 캜 to prepare a silane-modified polythiophene.

40 g of the surface-modified polythiophene and 1 ml of 3-aminopropyltriethoxysilane were reacted at 25 ° C. for 4 hours in a mixed solution containing ethanol and water at a ratio of 80:20 (v / v) Only a precipitated portion was obtained by a separator, followed by vacuum drying to prepare a silane-modified polythiophene.

≪ Examples 1 to 3 and Comparative Examples 1 and 2 >

The mixture was mixed with a Banbury mixer at 155 ° C in the composition shown in Table 1 below, and vulcanized at 145 ° C for 40 minutes to prepare a rubber specimen.

division Comparative Example 1 Comparative Example 2 Comparative Example 3 Example 1 Example 2 Example 3 Natural rubber 50 50 50 50 50 50 Butadiene rubber 50 50 50 50 50 50 Bromo-isobutene-isoprene rubber - - 20 5 20 30 The hydroxy-modified polythiophene - - 10 - - - Silane-modified polythiophene - - - 5 10 15 Carbon black (N550) 60 45 50 55 50 45 Zinc oxide 3 3 3 3 3 3 Stearic acid 2 2 2 2 2 2 Antioxidant 2 2 2 2 2 2 sulfur 1.7 1.7 1.7 1.7 1.7 1.7

<Experimental Example>

The rubber specimens prepared in Examples 1 to 3 and Comparative Examples 1 and 2 were measured for rotation resistance (Tan 60 ° C) and electrical resistance by ASTM method. The results are shown in Table 2 below.

In the following Table 2, Tan 60 ° C is a measure of the rotational resistance, which means that the higher the value, the better.

The electrical resistance is the minimum resistance measured under conditions of relative humidity 50% and temperature 23 ° C.

division Comparative Example 1 Comparative Example 2 Comparative Example 3 Example 1 Example 2 Example 3 LRR performance
(Tan 60 C) 100% 102% 110% 105% 107% 108% Electrical resistance
(Ω) 1.0 x 10 ^ 7 1.0 x 10 ^ 8 1.0 x 10 ^ 8 1.0 x 10 ^ 7 1.0 x 10 ^ 7 1.0 x 10 ^ 7

As can be seen from the results shown in Table 2, the rubber composition of the present invention including the silane-modified polythiophene as a conductive polymer material is excellent in electrical resistance performance while maintaining rotational resistance.

Claims (5)

Wherein the silane comprises 5 to 15 parts by weight of a silane-modified polythiophene based on 100 parts by weight of the raw rubber, wherein the silane is 3-aminopropyltriethoxysilane or 3-mercaptopropyltriethoxysilane. Month rubber composition. The anti-static sidewall rubber composition according to claim 1, wherein the silane-modified polythiophene is silane-bonded to the surface of the modified polythiophene by plasma treatment or acid treatment. delete The antistatic sidewall rubber composition according to claim 1, further comprising 30 to 60 parts by weight of carbon black per 100 parts by weight of the raw rubber. A tire comprising the rubber composition of any one of claims 1 to 4.