KR100227567B1 - A rubber composition for tube - Google Patents

Abstract

The present invention relates to a rubber composition for a tube.

인 이소부틸렌-시클로펜타디엔 고무를 30 내지 100중량부 사용하여 이루어진 튜브용 고무 조성물을 제공하는 것이다.In the rubber composition for tubes, the present invention has a number average molecular weight of 100,000 or more as a rubber substrate and an unsaturation of 2 to 20 mol.

It is providing the rubber composition for tubes made from 30 to 100 parts by weight of phosphorus isobutylene-cyclopentadiene rubber.

Such a rubber composition has a high vulcanization rate, excellent air permeability and aging resistance, and is preferably used for rubber for tubes.

Description

Rubber composition for tubes

The present invention relates to a rubber composition for tubes having improved air permeability and ozone crack resistance. More particularly, the present invention relates to a rubber composition for a tube that improves air permeability and ozone crack resistance by using a rubber composition using a rubber substrate in a ring structure where the double bond is not a rubber main chain.

As the rubber for a tube conventionally used, a composition based on natural rubber and a composition based on isobutylene-isoprene rubber are mainly used.

In the case of a rubber composition based on a double natural rubber, there are many double bonds in the main chain of the rubber, so that the vulcanization rate is high, but it is a problem when the air resistance and aging resistance are poor.

정도) 내공기 투과성 및 내노화성이 천연 고무를 사용한 고무 조성물 보다 양호하지만, 그러나 소량 존재하는 이중결합이 튜브 내부의 높은 공기압과 열에 의해 끊어져 결과적으로 크랙이 발생되는 문제가 있으며, 또한 가류속도가 낮은 단점이 있다.In addition, in the case of a rubber composition based on isobutylene-isoprene rubber, there are few double bonds in the rubber main chain (about 2 mol)

Degree) air permeability and aging resistance is better than rubber composition using natural rubber, but there is a problem that small amount of double bonds are broken by high air pressure and heat inside the tube and consequently crack, and also low vulcanization rate There are disadvantages.

Accordingly, the present invention solves this problem, and the vulcanization rate is fast due to the increase of the double bond content, and at the same time, since there are double bonds in the ring structure instead of the main chain of rubber, the air permeability and ozone crack performance of the double bond increases. It aims at providing the rubber composition which can prevent a fall.

인 이소부틸렌-시클로펜타디엔 고무를 30 내지 100중량부 사용하여 이루어진 튜브용 고무 조성물이다.In the rubber composition for tubes, the present invention has a number average molecular weight of 100,000 or more as a rubber substrate and an unsaturation of 2 to 20 mol.

It is a rubber composition for tubes formed using 30 to 100 parts by weight of phosphorus isobutylene-cyclopentadiene rubber.

Hereinafter, the present invention will be described in detail.

인 이소부틸렌-시클로펜타디엔 고무를 30 내지 100중량부 사용하여 이루어진 튜브용 고무 조성물로서, 이와 같은 고무 조성물은 가류속도가 빠르고, 내공기 투과성 및 내노화성이 우수하여 튜브용 고무에 바람직하게 사용된다.In the rubber composition for tubes, the present invention has a number average molecular weight of 100,000 or more as a rubber substrate and an unsaturation of 2 to 20 mol.

A rubber composition for tubes comprising 30 to 100 parts by weight of phosphorus isobutylene-cyclopentadiene rubber, wherein such rubber composition has a high vulcanization rate, excellent air permeability and aging resistance, and is preferably used for rubber for tubes. do.

인 이소부틸렌-메틸시클로펜타디엔-시클로펜타디엔 고무가 사용될 수 있다.In the present invention, in place of the isobutylene-cyclopentadiene rubber, the number average molecular weight is 100,000 or more, and the unsaturation is 2 to 20 moles.

Phosphorus isobutylene-methylcyclopentadiene-cyclopentadiene rubber may be used.

In addition, isobutylene-cyclopentadiene rubber and isobutylene-methylcyclopentadiene-cyclopentadiene rubber may increase the double bond and increase the vulcanization rate than isobutylene-isoprene rubber composition. Since the position is in the ring structure rather than the rubber main chain, even if the double bond is decomposed by heat or oxygen, only the ring structure is cut and the main chain remains. For this reason, no crack is generated in the tube, and at the same time, the air permeability is maintained in a good state.

In addition, in the case of the isobutylene-isoprene rubber composition, if the isoprene content is increased to increase the vulcanization rate, the air permeability decreases, but isobutylene-cyclopentadiene rubber or isobutylene-methylcyclopenta used in the present invention. The diene-cyclopentadiene rubber may improve the air permeability as the cyclopentadiene or methylcyclopentadiene content is increased, thereby preventing the air permeability decrease due to the increase in the double bond content.

The isobutylene-cyclopentadiene rubber and isobutylene-methylcyclopentadiene-cyclopentadiene rubber used above are required to have a number average molecular weight of 100,000 or more. If the number average molecular weight is less than 100,000, it is not preferable because it does not exhibit the required physical properties.

의 범위인 것이 바람직하며, 2몰

미만인 경우 가류속도가 너무 느려 바람직하지 않고, 20몰

를 초과하는 경우 가류속도는 빨라지나 유리전이온도가 상승하여 저온에서의 탄성이 낮아지는 단점이 있다.The isobutylene-cyclopentadiene rubber and the isobutylene-methylcyclopentadiene-cyclopentadiene rubber have an unsaturation of 2 to 20 moles.

It is preferably in the range of 2 mol

Less than 20 mol

If it exceeds, the vulcanization rate is faster, but the glass transition temperature is increased, so the elasticity at low temperature is lowered.

Hereinafter, the invention will be described in more detail with reference to Examples.

Example 1

100 parts by weight of isobutylene-cyclopentadiene rubber (hereinafter referred to as ICR) as a rubber base material, 50 parts by weight of carbon black, 17 parts by weight of oil, 1 part by weight of adhesive, 0.3 parts by weight of stearic acid, 0.7 parts by weight of calcium stearate 3 parts by weight of zinc oxide, 2 parts by weight of tetramethylthiuram disulfide, and 1 part by weight of sulfur were mixed with the rubber substrate, followed by vulcanization at 170 ° C. The air permeability and dynamic fatigue characteristics of the specimens prepared from the obtained rubber composition for tubes were measured before and after aging, and the results are shown in Table 1.

Example 2

100 parts by weight of isobutylene-methylcyclopentadiene-cyclopentadiene rubber (hereinafter referred to as IMCR) as a rubber base material, 50 parts by weight of carbon black, 17 parts by weight of oil, 1 part by weight of adhesive, 0.3 parts by weight of stearic acid, 0.7 parts by weight of calcium stearate, 3 parts by weight of zinc oxide, 2 parts by weight of tetramethylthiuram disulfide, and 1 part by weight of sulfur were mixed with the rubber substrate, followed by vulcanization at 170 ° C. The air permeability and dynamic fatigue characteristics of the specimens prepared from the obtained rubber composition for tubes were measured before and after aging, and the results are shown in Table 1.

Comparative Example 1

100 parts by weight of isobutylene-isoprene rubber (hereinafter referred to as IIR) as a rubber base material, 50 parts by weight of carbon black, 17 parts by weight of oil, 1 part by weight of adhesive, 0.3 parts by weight of stearic acid, 0.7 parts by weight of calcium stearate , 3 parts by weight of zinc oxide, 2 parts by weight of tetramethylthiuram disulfide, and 1 part by weight of sulfur were mixed with the rubber substrate, followed by vulcanization at 170 ° C. The air permeability and dynamic fatigue characteristics of the specimens prepared from the obtained tube composition were measured before and after aging, and the results are shown in Table 1.

ML1 + 8 ＠ 125C means the Mooney viscosity measured after 8 minutes of preheating at 125 ° C for 1 minute using a large rotor in a Mooney Viscometer.

반복적인 신장하에서 절단시까지의 회수를 의미한다.Fatigue-to-Failure: This item shows the dynamic fatigue characteristics. It is measured using a Fatigue-to-Failure tester.

The number of times from cutting under repeated stretching to cutting.

DeMattia: Shows the length of crack growth through repeated fatigue.

As shown in Table 1, the rubber composition (Examples 1, 2) using isobutylene-cyclopentadiene rubber or isobutylene-methylcyclopentadiene-cyclopentadiene rubber is a rubber using isobutylene-isoprene rubber. Compared with the composition (Comparative Example 1), it can be seen that the crack growth rate and the air permeability are good before aging, and the dynamic fatigue characteristics and the air permeability are excellent after aging.

As described above, in the rubber composition for a tube of the present invention, since the double bond is present in the ring structure rather than the main chain of the rubber, the vulcanization rate increases with the increase of the double bond, and the double bond in the main chain is broken by air pressure and heat and is cracked. The possibility of this occurring is reduced, thereby improving air resistance and aging resistance.

Claims (1)

Rubber composition for tubes WHEREIN: The number average molecular weight is 100,000 or more as a rubber base material, and an unsaturation is 2-20 mol.

A rubber composition for a tube, comprising phosphorus isobutylene-methylcyclopentadiene-cyclopentadiene rubber.